2013 21st IEEE International Conference on Network Protocols, ICNP 2013, Göttingen, Germany, October 7-10, 2013. IEEE 【DBLP Link】
【Paper Link】 【Pages】:1-10
【Authors】: René Hummen ; Hanno Wirtz ; Jan Henrik Ziegeldorf ; Jens Hiller ; Klaus Wehrle
【Abstract】: Recent standardization efforts focus on a number of lightweight IP security protocol variants for end-to-end security in the Internet of Things (IoT), most notably DTLS, HIP DEX, and minimal IKEv2. These protocol variants commonly consider public-key-based cryptographic primitives in their protocol design for peer authentication and key agreement. In this paper, we identify several performance and security issues that originate from these public-key-based operations on resource-constrained IoT devices. To illustrate their impact, we additionally quantify these protocol limitations for HIP DEX. Most importantly, we find that public-key-based operations significantly hamper a peer's availability and response time during the protocol handshake. Hence, IP security protocols in the IoT must be tailored to reduce the need for expensive cryptographic operations, to protect resource-constrained peers against DoS attacks targeting these cryptographic operations, and to account for high message processing times. To this end, we present three complementary, lightweight protocol extensions for HIP DEX: i) a comprehensive session resumption mechanism, ii) a collaborative puzzle-based DoS protection mechanism, and iii) a refined retransmission mechanism. Our focus on common protocol functionality allows to generalize our proposed extensions to the wider scope of DTLS and IKE. Finally, our evaluation confirms the considerable achieved improvements at modest trade-offs.
【Keywords】: Protocols; Hip; Cryptography; DH-HEMTs; IP networks; Internet
【Paper Link】 【Pages】:1-10
【Authors】: Alex X. Liu ; Eric Norige ; Sailesh Kumar
【Abstract】: Regular Expression (RegEx) matching is the core operation of various network security devices such as IPSes. Despite much effort, it has remained an unsolved problem to achieve both high speed and low memory requirements.XFA, the state-of-the-art software RegEx matching solution, has two fundamental limitations: (1) XFA construction is hard to automate as it requires manual annotation by human experts, and (2) XFA is hard to implement in ASIC as the program executed upon reaching a state requires much of the complexity of a general purpose CPU. In this paper, we propose HASIC, a History-based Finite Automaton (HFA [11]) based RegEx matching scheme. HASIC can exponentially reduce state explosion by testing, setting, and clearing an auxiliary vector of history bits. Compared with XFA, HASIC advances the state of the art because it can be fully automated and it is ASIC friendly. HASIC only uses three simple bit operations and they are easy to implement in ASIC. We conducted experiments using real-world RegEx sets and various traffic traces. Experimental results show that for packet processing speed, software HFA runs an average of 3.34 times faster than XFA, for automata construction speed HFA is orders of magnitude faster than DFA, and for memory image size HFA is an average of 20 times smaller than DFA.
【Keywords】: History; Automata; Pattern matching; Educational institutions; Explosions; Random access memory; Application specific integrated circuits
【Paper Link】 【Pages】:1-10
【Authors】: Muhammad Usman Ilyas ; Muhammad Zubair Shafiq ; Alex X. Liu ; Hayder Radha
【Abstract】: We present a novel attack on relayed instant messaging (IM) traffic that allows an attacker to infer who's talking to whom with high accuracy. This attack only requires collection of packet header traces between users and IM servers for a short time period, where each packet in the trace goes from a user to an IM server or vice-versa. The specific goal of the attack is to accurately identify a candidate set of top-k users with whom a given user possibly talked to, while using only the information available in packet header traces (packet payloads cannot be used because they are mostly encrypted). Towards this end, we propose a wavelet-based scheme, called COmmunication Link De-anonymization (COLD), and evaluate its effectiveness using a real-world Yahoo! Messenger data set. The results of our experiments show that COLD achieves a hit rate of more than 90% for a candidate set size of 10. For slightly larger candidate set size of 20, COLD achieves almost 100% hit rate. In contrast, a baseline method using time series correlation could only achieve less than 5% hit rate for similar candidate set sizes.
【Keywords】: Servers; Correlation; Relays; Wavelet transforms; Vectors; Time series analysis; IP networks
【Paper Link】 【Pages】:1-10
【Authors】: Dan Ma ; Chen Qian ; Wenpu Li ; Jinsong Han ; Jizhong Zhao
【Abstract】: Physical-layer identification utilizes unique features of wireless devices as their fingerprints, providing authenticity and security guarantee. Prior physical-layer identification techniques on RFID tags require non-generic equipments and are not fully compatible with existing standards. In this paper, we propose a novel physical-layer identification system, GenePrint, for UHF passive tags. The GenePrint prototype system is implemented by a commercial reader, a USRP-based monitor, and off-the-shelf UHF passive tags. Our solution is generic and completely compatible with the existing standard, EPCglobal C1G2 specification. GenePrint leverages the internal similarity among the pulses of tags' RN16 preamble signals to extract a hardware feature as the fingerprint. We conduct extensive experiments on over 10,000 RN16 preamble signals from 150 off-the-shelf RFID tags. The results show that GenePrint achieves a high identification accuracy of 99.68%+. The feature extraction of GenePrint is resilient to various malicious attacks, such as the feature replay attack.
【Keywords】: Feature extraction; Hardware; Radiofrequency identification; Vectors; Standards; Monitoring; Accuracy
【Paper Link】 【Pages】:1-10
【Authors】: Ahmed Osama Fathy Atya ; Azeem Aqil ; Shailendra Singh ; Ioannis Broustis ; Karthikeyan Sundaresan ; Srikanth V. Krishnamurthy
【Abstract】: Malicious interference injection or jamming is one of the simplest ways to disrupt wireless communications. Prior approaches can alleviate jamming interference to a limited extent; they are especially vulnerable to a reactive jammer i.e., a jammer that injects noise upon sensing a legitimate transmission or wideband jamming. In this paper, we leverage the inherent features of OFDM (Orthogonal Frequency Division Multiplexing) to cope with such attacks. Specifically, via extensive experiments, we observe that the jamming signal experiences differing levels of fading across the composite sub-carriers in its transmission bandwidth. Thus, if the legitimate transmitter were to somehow exploit the relatively unaffected sub-carriers to transmit data to the receiver, it could achieve reasonable throughputs, even in the presence of the active jammer. We design and implement JIMS, a Jamming Interference Mitigation Scheme that exploits the above characteristic by overcoming key practical challenges. Via extensive testbed experiments and simulations we show that JIMS achieves a throughput restoration of up to 75% in the presence of an active jammer.
【Keywords】: Jamming; Interference; OFDM; Signal to noise ratio; Vectors; Fading; Throughput
【Paper Link】 【Pages】:1-10
【Authors】: Giovanna Carofiglio ; Massimo Gallo ; Luca Muscariello ; Michele Papalini ; Sen Wang
【Abstract】: The evolution of the Internet into a distributed Information access system calls for a paradigm shift to enable an evolvable future network architecture. Information-Centric Networking (ICN) proposals rethink the communication model around named data, in contrast with the host-centric transport view of TCP/IP. Information retrieval is natively pull-based, driven by user requests, point-to-multipoint and intrinsically coupled with in-network caching. In this paper, we tackle the problem of joint multipath congestion control and request forwarding in ICN for the first time. We formulate it as a global optimization problem with the twofold objective of maximizing user throughput and minimizing overall network cost. We solve it via decomposition and derive a family of optimal congestion control strategies at the receiver and of distributed algorithms for dynamic request forwarding at network nodes. An experimental evaluation of our proposal is carried out in different network scenarios to assess the performance of our design and to highlight the benefits of an ICN approach.
【Keywords】: Receivers; Delays; Minimization; IP networks; Optimization; Dynamic scheduling; Joints
【Paper Link】 【Pages】:1-10
【Authors】: Yonggong Wang ; Zhenyu Li ; Gareth Tyson ; Steve Uhlig ; Gaogang Xie
【Abstract】: Content-Centric Networking (CCN) is a promising framework for evolving the current network architecture, advocating ubiquitous in-network caching to enhance content delivery. Consequently, in CCN, each router has storage space to cache frequently requested content. In this work, we focus on the cache allocation problem: namely, how to distribute the cache capacity across routers under a constrained total storage budget for the network. We formulate this problem as a content placement problem and obtain the exact optimal solution by a two-step method. Through simulations, we use this algorithm to investigate the factors that affect the optimal cache allocation in CCN, such as the network topology and the popularity of content. We find that a highly heterogeneous topology tends to put most of the capacity over a few central nodes. On the other hand, heterogeneous content popularity has the opposite effect, by spreading capacity across far more nodes. Using our findings, we make observations on how network operators could best deploy CCN caches capacity.
【Keywords】: Resource management; Topology; Network topology; Servers; Optimization; Measurement; Complexity theory
【Paper Link】 【Pages】:1-10
【Authors】: Zhenkai Zhu ; Alexander Afanasyev
【Abstract】: In supporting many distributed applications, such as group text messaging, file sharing, and joint editing, a basic requirement is the efficient and robust synchronization of knowledge about the dataset such as text messages, changes to the shared folder, or document edits. We propose ChronoSync protocol, which exploits the features of the Named Data Networking architecture to efficiently synchronize the state of a dataset among a distributed group of users. Using appropriate naming rules, ChronoSync summarizes the state of a dataset in a condensed cryptographic digest form and exchange it among the distributed parties. Differences of the dataset can be inferred from the digests and disseminated efficiently to all parties. With the complete and up-to-date knowledge of the dataset changes, applications can decide whether or when to fetch which pieces of the data. We implemented ChronoSync as a C++ library and developed two distributed application prototypes based on it. We show through simulations that ChronoSync is effective and efficient in synchronization dataset state, and is robust against packet losses and network partitions.
【Keywords】: Synchronization; Protocols; Distributed databases; Cryptography; Robustness; Knowledge engineering; Internet
【Paper Link】 【Pages】:1-10
【Authors】: Kyung-Wook Hwang ; Vijay Gopalakrishnan ; Rittwik Jana ; Seungjoon Lee ; Vishal Misra ; K. K. Ramakrishnan ; Dan Rubenstein
【Abstract】: We propose Joint-Family, a protocol that combines peer-to-peer (P2P) and adaptive bitrate (ABR) streaming for video-on-demand (VoD). While P2P for VoD and ABR have been proposed previously, they have not been studied together because they attempt to tackle problems with seemingly orthogonal goals. We motivate our approach through analysis that overcomes a misconception resulting from prior analytical work, and show that the popularity of a P2P swarm and seed staying time has a significant bearing on the achievable per-receiver download rate. Specifically, our analysis shows that popularity affects swarm efficiency when seeds stay “long enough”. We also show that ABR in a P2P setting helps viewers achieve higher playback rates and/or fewer interruptions. We develop the Joint-Family protocol based on the observations from our analysis. Peers in Joint-Family simultaneously participate in multiple swarms to exchange chunks of different bitrates. We adopt chunk, bitrate, and peer selection policies that minimize occurrence of interruptions while delivering high quality video and improving the efficiency of the system. Using traces from a large-scale commercial VoD service, we compare Joint-Family with existing approaches for P2P VoD and show that viewers in Joint-Family enjoy higher playback rates with minimal interruption, irrespective of video popularity.
【Keywords】: Streaming media; Bit rate; Peer-to-peer computing; Protocols; Markov processes; Analytical models; Mathematical model
【Paper Link】 【Pages】:1-10
【Authors】: Luwei Cheng ; Cho-Li Wang ; Francis C. M. Lau
【Abstract】: While modern datacenters are increasingly adopting virtual machines (VMs) to provide elastic cloud services, they still rely on traditional TCP for congestion control. In virtualized datacenters, TCP endpoints are separated by a virtualization layer and subject to the intervention of the hypervisor's scheduling. Most previous attempts focused on tuning the hypervisor layer to try to improve the VMs' I/O performance, and there is very little work on how a VM's guest OS may help the transport layer to adapt to the virtualized environment. In this paper, we find that VM scheduling delays can heavily contaminate RTTs as sensed by VM senders, preventing TCP from correctly learning the physical network condition. After giving an account of the source of the problem, we propose PVTCP, a ParaVirtualized TCP to counter the distorted congestion information caused by VM scheduling on the sender side. PVTCP is self-contained, requiring no modification to the hypervisor. Experiments show that PVTCP is much more effective in addressing incast congestion in virtualized datacenters than standard TCP.
【Keywords】: Delays; Virtual machine monitors; Receivers; Virtualization; Standards; Switches; Scheduling
【Paper Link】 【Pages】:1-10
【Authors】: Haijun Geng ; Xingang Shi ; Xia Yin ; Zhiliang Wang
【Abstract】: High reliability is always pursued by network designers. Multipath routing can provide multiple paths for transmission and failover, and is considered to be effective in the improvement of the network reliability. However, existing multipath routing algorithms focus on how to find as many paths as possible, rather than their computation or communication overhead. We propose a dynamic distributed multipath algorithm (DMPA) to help a router in a link-state network find multiple nexthops for each destination. A router runs the algorithm locally and independently, where only one single shortest path tree (SPT) needs to be constructed, and no message other than the basic link states is disseminated. DMPA maintains the SPT and dynamically adjusts it in response to network state changes, so the sets of nexthops can be incrementally and efficiently updated. At the same time, DMPA guarantees loop-freeness of the induced forwarding path by a partial order of the routers underpinning it. We evaluate DMPA and compare it with some latest multipath algorithms, using a set of real, inferred and synthetic topologies. The results show that DMPA can provide good reliability and fast recovery for the network with very low overhead.
【Keywords】: Heuristic algorithms; Routing; Equations; Reliability; Artificial neural networks; Computer network reliability; Internet
【Paper Link】 【Pages】:1-10
【Authors】: Guoxin Liu ; Haiying Shen ; Harrison Chandler
【Abstract】: Though the new OSN model with many worldwide distributed small datacenters helps reduce service latency, it brings a problem of higher inter-datacenter communication load. In Facebook, each datacenter has a full copy of all data and the master datacenter updates all other datacenters, which obviously generates tremendous load in this new model. Distributed data storage that only stores a user's data to his/her geographically-closest datacenters mitigates the problem. However, frequent interactions between far-away users lead to frequent inter-datacenter communication and hence long service latency. In this paper, we aim to reduce inter-datacenter communications while still achieve low service latency. We first verify the benefits of the new model and present OSN typical properties that lay the basis of our design. We then propose Selective Data replication mechanism in Distributed Datacenters (SD3). In SD3, a datacenter jointly considers update rate and visit rate to select user data for replication, and further atomizes a user's different types of data (e.g., status update, friend post) for replication, making sure that a replica always reduces inter-datacenter communication. The results of trace-driven experiments on the real-world PlanetLab testbed demonstrate the higher efficiency and effectiveness of SD3 in comparison to other replication methods.
【Keywords】: Load modeling; Distributed databases; Data models; Communities; Extraterrestrial measurements
【Paper Link】 【Pages】:1-10
【Authors】: Jian Guo ; Fangming Liu ; Haowen Tang ; Yingnan Lian ; Hai Jin ; John C. S. Lui
【Abstract】: With wide application of virtualization technology, tenants are able to access isolated cloud services by renting the shared resources in datacenters. Unlike resources such as CPU and memory, datacenter network, which relies on traditional transport-layer protocols, suffers unfairness due to a lack of VM-level network isolation. In this paper, we propose Falloc, a new bandwidth allocation protocol, towards VM-based fairness across the datacenter with two main objectives: (i) guarantee bandwidth for VMs based on their base bandwidth requirements, and (ii) share residual bandwidth in proportion to weights of VMs. To design Falloc, we model the datacenter bandwidth allocation as a bargaining game and propose a distributed algorithm to achieve the asymmetric Nash bargaining solution (NBS). We apply the theory to practice by implementing Falloc with OpenFlow in experiments under diversed scenarios, which shows that Falloc can achieve fairness by adapting to different network requirements of VMs, and balance the tradeoff between bandwidth guarantee and proportional bandwidth share. By carrying out large scale trace-driven simulations using real-world Mapreduce workload, we show that Falloc achieves high utilization and maintains fairness among VMs in datacenters.
【Keywords】: Bandwidth; Servers; Resource management; Channel allocation; Protocols; Games; Vectors
【Paper Link】 【Pages】:1-10
【Authors】: Marco Chiesa ; Luca Cittadini ; Giuseppe Di Battista ; Laurent Vanbever ; Stefano Vissicchio
【Abstract】: Because of its practical relevance, the Border Gateway Protocol (BGP) has been the target of a huge research effort since more than a decade. In particular, many contributions aimed at characterizing the computational complexity of BGP-related problems. In this paper, we answer computational complexity questions by unveiling a fundamental mapping between BGP configurations and logic circuits. Namely, we describe simple networks containing routers with elementary BGP configurations that simulate logic gates, clocks, and flip-flops, and we show how to interconnect them to simulate arbitrary logic circuits. We then investigate the implications of such a mapping on the feasibility of solving BGP fundamental problems, and prove that, under realistic assumptions, BGP has the same computing power as a Turing Machine. We also investigate the impact of restrictions on the expressiveness of BGP policies and route propagation (e.g., route propagation rules in iBGP and Local Transit Policies in eBGP) and the impact of different message timing models. Finally, we show that the mapping is not limited to BGP and can be applied to generic routing protocols that use several metrics.
【Keywords】: Logic gates; Peer-to-peer computing; Routing protocols; Logic circuits; Routing; Clocks; Integrated circuit modeling
【Paper Link】 【Pages】:1-10
【Authors】: Nithin Michael ; Ao Tang ; Dahai Xu
【Abstract】: Current intra-domain routing protocols like OSPF and IS-IS use link-state routing algorithms with hop-by-hop forwarding that sacrifice traffic engineering performance for ease of implementation and management. Though optimal traffic engineering algorithms exist, they tend to be either not link-state algorithms or to require source routing - characteristics that make them difficult to implement. As the focus of this paper, we introduce HALO, the first optimal link-state routing algorithm with hop-by-hop forwarding, where link weights can be calculated locally. Furthermore, our solution can adapt to changing traffic patterns automatically. The optimality of the algorithm is proved theoretically and also verified numerically.
【Keywords】: Routing; Routing protocols; Internet; Trajectory; Cost function
【Paper Link】 【Pages】:1-10
【Authors】: Yuan Yang ; Dan Wang ; Mingwei Xu ; Suogang Li
【Abstract】: In this paper we study energy conservation in the Internet. We observe that different traffic volumes on a link can result in different energy consumption; this is mainly due to such technologies as trunking (IEEE 802.1AX), adaptive link rates, etc. We design a green Internet routing scheme, where the routing can lead traffic in a way that is green. We differ from previous studies where they switch network components, such as line cards and routers, into sleep mode. We do not prune the Internet topology. We first develop a power model, and validate it using real commercial routers. Instead of developing a centralized optimization algorithm, which requires additional protocols such as MPLS to materialize in the Internet, we choose a hop-by-hop approach. It is thus much easier to integrate our scheme into the current Internet. We progressively develop three algorithms, which are loop-free, maximize energy conservation, and jointly consider green and QoS requirements such as path stretch. We comprehensively evaluate our algorithms through simulations on synthetic and real topologies and traffic traces. We show that the power saving in the line cards can be as much as 50%.
【Keywords】: Routing; Green products; Energy conservation; Power demand; Internet; Algorithm design and analysis; Energy consumption
【Paper Link】 【Pages】:1-10
【Authors】: Wilko Henecka ; Matthew Roughan
【Abstract】: Security of routing protocols is a critical issue, as shown by the increasing number of attacks on the Internet's routing infrastructure. One often overlooked aspect of security is privacy. In the context of a routing protocol we mean the ability of a router to keep information such as its routing policies private. BGP does this to some extent through design. An Autonomous System's policies are not explicitly revealed to other participants in the routing protocol. Nevertheless, BGP still reveals a great deal of information about the Internet and its participants. We propose a privacy-preserving routing protocol called STRIP that reveals very little information to participants in the protocol. For instance, participants can find shortest-paths to destinations in the network without ever learning the path lengths. Such privacy could be useful for a range of reasons: preserving the proprietary information captured in a routing policy, or preventing an attacker from gaining valuable information about the network. We show the feasibility, performance, and costs of STRIP with simulations and implementations of the protocol.
【Keywords】: Routing protocols; Routing; Strips; Encryption; Public key
【Paper Link】 【Pages】:1-10
【Authors】: François Clad ; Pascal Mérindol ; Stefano Vissicchio ; Jean-Jacques Pansiot ; Pierre François
【Abstract】: Manageability and evolvability are crucial needs for IP networks. Unfortunately, planned topological changes may lead to transient forwarding loops in link-state routing protocols commonly used in IP networks. These lead to service unavailability, reducing the frequency at which operators can adapt the network topology. Prior works proved that the state of a given link can be modified while avoiding forwarding inconsistencies without changing protocol specifications. In this paper, we study the more general problem of gracefully modifying the state of an entire router, while minimizing the induced operational impact. As opposed to a single-link modification, the router update problem is k-dimensional for a node of degree k. Moreover, we show that the interplay between operations applied at the router granularity can lead to loops that do not occur considering a single-link modification. In this paper, we present an efficient algorithm that computes minimal sequences of weights to be configured on the links of the updated node. Based on real IP network topologies, we show that the size of such sequence is limited in practice.
【Keywords】: Lead; IP networks; Convergence
【Paper Link】 【Pages】:1-6
【Authors】: Ruidong Li ; Kazuyuki Morioka ; Yasunori Owada ; Masaaki Ohnishi ; Hiroaki Harai
【Abstract】: We are designing authentication framework for a regional network with concerns on fast authentication and disaster robustness. To achieve this goal, we previously proposed a proactive and distributed authentication framework (PDAF). In this paper, to enhance the robustness of PDAF, we add temporary registration and authentication procedures in a disaster scenario and the distributed regional network key server (RNKS) mechanism. Meanwhile, we optimize PDAF messaging through reducing redundancy to improve the performance. The proposed PDAF is a fully distributed design, which is intrinsically more robust than the existing authentication framework. In particular, we implement the PDAF over an existing regional network and measure the performance of PDAF. This shows that network scale and offered traffic load do not influence the PDAF's authentication time, which is usually around 31 ms under our experiment environment, because neighboring networking devices directly authenticate end devices.
【Keywords】: robustness; Regional network; authenticaiton
【Paper Link】 【Pages】:1-10
【Authors】: Shuaiyuan Zhou ; Zhenghao Zhang
【Abstract】: In this paper, we propose L2Relay, a novel packet relay protocol for Wi-Fi networks that can improve the performance and extend the range of the network. A device running L2Relay is referred to as a relayer, which overhears the packet transmissions and retransmits a packet on behalf of the Access Point (AP) or the node if no ACK is overheard. One important feature of L2Relay is its ubiquitous compatibility, i.e., it is compatible with any Wi-Fi devices, such that one or multiple relayers can be installed in any network easily without any modification to the AP or the nodes. L2Relay is a layer 2 solution that exploits many layer 2 functionalities such as carrier sense. It encompasses unique solutions to link quality measurement, rate adaptation, and relayer selection. We implement L2Relay in the OpenFWWF platform and compare it against the baseline network without a relayer as well as a popular commercial Wi-Fi range extender. Our results show that L2Relay achieves overall better performance than both compared schemes.
【Keywords】: Relays; Estimation; Protocols; IEEE 802.11 Standards; Radiation detectors; Robustness
【Paper Link】 【Pages】:1-12
【Authors】: Yigal Bejerano ; Jaime Ferragut ; Katherine Guo ; Varun Gupta ; Craig Gutterman ; Thyaga Nandagopal ; Gil Zussman
【Abstract】: IEEE 802.11-based wireless local area networks, referred to as WiFi, have been globally deployed and the vast majority of mobile devices are currently WiFi-enabled. While WiFi has been proposed for multimedia content distribution, its lack of adequate support for multicast services hinders its ability to provide multimedia content distribution to a large number of devices. We propose AMuSe, a scalable and adaptive interference mitigation solution for WiFi multicast services which is based on accurate receiver feedback and that incurs a small control overhead. Specifically, we develop a scheme for dynamic selection of a subset of the multicast receivers as feedback nodes, which periodically send information, such as channel quality or received packet statistics, to the multicast sender. This feedback information is used by the multicast sender to optimize the multicast service quality, e.g., by dynamically adjusting the transmission bit-rate. Our proposed solution does not require any changes to the standards or any modifications to the WiFi devices. We have implemented the proposed solution in the ORBIT testbed and evaluated its performance in large groups with approximately 250 receivers, both with and without interference sources. Our online experiments demonstrate that our system provides practical multicast services that can accommodate hundreds of receivers.
【Keywords】: Feedback Mechanism; 802.11; WiFi; Multicast
【Paper Link】 【Pages】:1-10
【Authors】: Wenjie Zhou ; Kannan Srinivasan ; Prasun Sinha
【Abstract】: With recent advances in wireless systems, wireless in-band full duplex is proven possible. Prior work primarily allows a full duplex receiver to either send back a packet (bi-directional mode) or to forward another packet to its neighbor (secondary transmission). In our work, we look beyond a node pair and explore how a network can best utilize the full duplex capability. When a full duplex receiver does not have any packets to send back, concurrent transmissions (exposed transmissions) can be initiated. In a distributed channel access protocol, rapid signaling is crucial to identify the best mode for a given pair of transmitter and receiver, and to inform potential exposed terminals of transmission opportunities. In this paper, we present, RCTC, a fast and low overhead signaling mechanism based on Pseudo-random Noise (PN) sequences to enable multi-modal operation of wireless links in a distributed channel access setting to support concurrent transmissions in the neighborhood. Our prototype with USRPs shows up to 78% throughput gain. Extensive simulations over larger networks show a throughput gain of up to 131% for RCTC over the native full duplex scheme and up to 111% over a scheme that enables secondary transmission.
【Keywords】: Receivers; Transmitters; Throughput; Bidirectional control; Equations; Interference; Wireless communication
【Paper Link】 【Pages】:1-10
【Authors】: Xiaoyu Ji ; Yuan He ; Jiliang Wang ; Kaishun Wu ; Ke Yi ; Yunhao Liu
【Abstract】: Packet corruption caused by collision is a critical problem that hurts the performance of wireless networks. Conventional medium access control (MAC) protocols resort to collision avoidance to maintain acceptable efficiency of channel utilization. According to our investigation and observation, however, collision avoidance comes at the cost of miscellaneous overhead, which oppositely hurts channel utilization, not to mention the poor resiliency and performance of those protocols in face of dense networks or intensive traffic. Discovering the ability to tolerate collisions at the physical layer implementations of wireless networks, we in this paper propose Coco, a MAC protocol that advocates simultaneous accesses from multiple senders to a shared channel, i.e., optimistically allowing collisions instead of simply avoiding them. With a simple but effective design, Coco addresses the key challenges in achieving collision tolerance, such as precise sender alignment and fine control of the transmission concurrency. We implement Coco in 802.15.4 networks and evaluate its performance through extensive experiments with 21 TelosB nodes. The results demonstrate that Coco is light-weight and enhances channel utilization by at least 20% in general cases, compared with state-of-the-arts protocols.
【Keywords】: Receivers; Protocols; Signal to noise ratio; Collision avoidance; Concurrent computing; IEEE 802.15 Standards; Timing
【Paper Link】 【Pages】:1-10
【Authors】: Pei Huang ; Xi Yang ; Li Xiao
【Abstract】: To support applications that demand high-speed wireless communication, the ongoing standardization of the next generation Wi-Fi increases the channel bonding from 40 MHz in 802.11n to 80, and even 160 MHz under certain conditions in 802.11ac. However, inefficiency and unfairness issues arise when devices that use different channel widths coexist in a contention domain. In this paper, we propose a dynamic channel bonding (DyB) protocol in which a node is allowed to start a transmission as long as there are some idle narrow channels and it gradually increases channel width during transmission whenever new narrow channels become available. A challenge is the communication over uncertain channels. To enable fast spectrum agreement between transmitter and receiver, a partial spectrum correlation method is introduced. In addition, DyB considers the severe contention in a wide band of spectrum. A compound preamble is designed to make collisions detectable in the frequency domain and a parallel bitwise arbitration is used to quickly resolve the collisions in the time domain. We implemented and evaluated the DyB through both the GNU Radio/USRP platform and ns-2 simulations. Experimental results and simulations show that DyB can well address the inefficiency and unfairness issues caused by heterogeneous radio coexistence.
【Keywords】: Receivers; Compounds; Radio transmitters; OFDM; Bonding; Binary codes
【Paper Link】 【Pages】:1-10
【Authors】: Xinlei Wang ; Jindan Zhu ; Amit Pande ; Arun Raghuramu ; Prasant Mohapatra ; Tarek F. Abdelzaher ; Raghu K. Ganti
【Abstract】: Location-based services are quickly becoming immensely popular. In addition to services based on users' current location, many potential services rely on users' location history, or their spatial-temporal provenance. Malicious users may lie about their spatial-temporal provenance without a carefully designed security system for users to prove their past locations. In this paper, we present the Spatial-Temporal provenance Assurance with Mutual Proofs (STAMP) scheme. In contrast to most existing location proof systems which rely on infrastructure like wireless APs, STAMP is based on co-located mobile devices mutually generating location proofs for each other. This makes STAMP desirable for a wider range of applications. STAMP ensures the integrity and non-transferability of the location proofs and protects users' privacy. We also examine different collusion scenarios and propose a light-weight entropy-based trust evaluation approach to detect fake proofs resulting from collusion attacks. Our prototype implementation on the Android platform shows that STAMP is low-cost in terms of computational and storage resources. Extensive simulation experiments show that our entropy-based trust model is able to achieve high (> 0.9) collusion detection accuracy.
【Keywords】: Protocols; Privacy; Mobile communication; Wireless communication; Mobile handsets; Cryptography
【Paper Link】 【Pages】:1-10
【Authors】: Xiaomei Zhang ; Guohong Cao
【Abstract】: Community has received considerable attention because of its application to many practical problems in mobile networks. However, when considering temporal information associated with community (i.e., transient community), most existing community detection methods fail due to their aggregation of the contact information into a single weighted or unweighted network. In this paper, we propose a contact-burst-based clustering method to detect transient communities by exploiting the pairwise contact processes. In this method, we formulate each pairwise contact process as regular appearance of contact bursts, during which most contacts between the pair of nodes happen. Based on such formulation, we detect transient communities by clustering the pairs of nodes with similar contact bursts together. We also propose a new data forwarding strategy for delay tolerant networks in which transient communities serve as the data forwarding unit. Evaluation results show that our strategy can achieve much higher data delivery ratio than traditional community-based strategies with comparable network overhead.
【Keywords】: Communities; Transient analysis; Clustering algorithms; Peer-to-peer computing; Delays; IEEE 802.11 Standards; Educational institutions
【Paper Link】 【Pages】:1-10
【Authors】: Rajesh Mahindra ; Mohammad Ali Khojastepour ; Honghai Zhang ; Sampath Rangarajan
【Abstract】: Mobile operators are witnessing a dramatic increase in traffic spurred by a combination of popularity of smartphones, innovative applications and diverse services. As mobile traffic transitions from being voice dominated to video and data dominated, the revenue per byte for the mobile operators is declining at an unhealthy rate. To counter the traffic growth and build cost-effective networks, many operators are now forging alliances for RAN (Radio Access Network) sharing to improve coverage and capacity at reasonable investments and operational costs. This paper presents the design and implementation of NetShare, a network-wide radio resource management framework that provides effective RAN Sharing. NetShare introduces a novel two-level scheduler split between the mobile gateway and the cellular basestations to effectively manage and allocate the wireless resources of the radio access network composed of multiple basestations among multiple different entities (such as operators, content providers, etc.) that share the network. Firstly, NetShare provides performance isolation across entities with a minimum guaranteed resource allocation to each entity across the network. Secondly, NetShare optimally distributes the resources to each entity across the network proportional to the resource demand at each basestation. Through extensive LTE-based system simulations and prototype evaluations on a WiMAX testbed, we show the efficacy of NetShare in (a) providing isolation across entities and (b) efficiently distributing resources for each entity across the network thus achieving high utilization of resources for an entity.
【Keywords】: Resource management; Radio access networks; Aggregates; Mobile communication; Logic gates; WiMAX
【Paper Link】 【Pages】:1-10
【Authors】: Vijay Gabale ; UmaMaheswari Devi ; Ravi Kokku ; Vinay Kolar ; Mukundan Madhavan ; Shivkumar Kalyanaraman
【Abstract】: We design and implement a novel system called Async, which enables a mobile network operator (MNO) to efficiently manage the growth of mobile data by leveraging the delay-elastic nature of certain applications and the price-sensitive nature of certain users. Specifically, Async introduces an alternate “asynchronous” content-delivery paradigm for heavy content (e.g., videos), and facilitates an MNO to negotiate with users a delay in delivery in exchange for appropriate incentives. The MNO uses the negotiated delays to actively manage Async flows to reduce congestion and improve the quality-of-experience (QoE) of both delayed and regular flows. We show that in comparison to state-of-the-art, Async's network-based flow management enhances QoE for more than 30% of the regular flows, with up to 60% improvement in per-flow QoE metric, while still meeting the negotiated delivery times of 95% of the delayed flows. Async also lowers the delivery times of delayed flows by ∼67% and significantly increases robustness to traffic unpredictability. Our design is robust to disconnections and does not require any modifications to existing network infrastructure and protocols. Our prototype deployment (using Apache's mod_proxy and an Android app) on live networks confirms Async's efficacy in meeting EDTs for diverse deployment scenarios.
【Keywords】: Videos; Delays; Throughput; Pricing; Interference; Mobile communication; Protocols
【Paper Link】 【Pages】:1-2
【Authors】: Vijay Gabale ; Vinay Kolar ; Uma Devi ; Mukundan Madhavan ; Ravi Kokku
【Abstract】: In this work, we demonstrate the design and implementation of a novel system called Async, which enables a mobile network operator (MNO) to efficiently manage the growth of mobile data. For this, we enable an opportunistic delivery model for the MNOs by leveraging the delay-elastic nature of certain applications such as video downloads, and the price-sensitive nature of certain users. Specifically, in Async, we enable an alternate content delivery paradigm that facilitates an MNO to control when, and at what price, the content is delivered to the users. In our system, users can select a price and expected delivery time (or EDT) option from a multitude of choices. We develop a prototype of such a system by extending Apache's mod_proxy module and by developing a service on the Android platform without requiring any modifications to existing network infrastructure or protocols. We demonstrate two applications using such a service: (1) download of large files, e.g., software updates, movie files, and (2) an educational App that downloads educational content on mobile devices.
【Keywords】: Mobile communication; Servers; Mobile computing; Internet; Software; Motion pictures; Schedules
【Paper Link】 【Pages】:1-10
【Authors】: Wai Kay Leong ; Yin Xu ; Ben Leong ; Zixiao Wang
【Abstract】: It is not uncommon for the uplink buffers of cellular data networks to be saturated when the uplink bandwidths are low. This can cause the ACK packets for a downlink TCP flow to be severely delayed. Since existing TCP implementations are ACK-clocked, the downstream flow will suffer significant degradation, causing the downlink to be under-utilized. We present a new TCP variant, called TCP Receiver-Rate Estimation (TCP-RRE), that addresses this problem directly by eliminating ACK clocking. Instead, it uses TCP timestamps to estimate the receiving rate at the receiver, which it then uses to determine the sending rate. We show that TCP-RRE is able to improve download speeds by 2 to 4 times compared to existing TCP variants in both simulation and on real commercial cellular data networks. Our solution is practical because it is compatible with existing TCP implementations, requires no modifications to existing mobile devices, and is thus immediately deployable in existing ISP proxies.
【Keywords】: Receivers; Delays; Mobile communication; Clocks; Legged locomotion; Bandwidth; Uplink
【Paper Link】 【Pages】:1-10
【Authors】: Wenping Liu ; Hongbo Jiang ; Yang Yang ; Zemeng Jin
【Abstract】: In sensor networks, skeleton extraction has emerged as an appealing approach to support many applications such as load-balanced routing and location-free segmentation. While significant advances have been made for 2D cases, so far skeleton extraction for 3D sensor networks has not been thoroughly studied. In this paper, we conduct the first work on the skeleton extraction in 3D sensor networks, and propose a unified framework for line-like skeleton extraction in both 2D and 3D sensor networks. Our algorithm has the following three steps: first, each node identifies itself as a skeleton node if the geodesic shortest paths between its nearest boundary nodes (referred to as feature nodes) decompose the boundary of the network into more than one connected component; second, each skeleton node is assigned a monotonically increasing importance measure according to the maximum Lebesgue measure of the connected components of the boundary such that the identified skeleton nodes are self-connected; and finally, the skeleton is pruned based on the proposed metric branch similarity. The proposed algorithm is connectivity-based, distributed and of low complexity. Extensive simulations show that it is robust to shape variations and boundary noise.
【Keywords】: Skeleton; Three-dimensional displays; Routing; Level measurement; Trajectory; Vectors; Routing protocols
【Paper Link】 【Pages】:1-10
【Authors】: Daibo Liu ; Zhichao Cao ; Jiliang Wang ; Yuan He ; Mengshu Hou ; Yunhao Liu
【Abstract】: Opportunistic routing, offering relatively efficient and adaptive forwarding in low-duty-cycled sensor networks, generally allows multiple nodes to forward the same packet simultaneously, especially in networks with intensive traffic. Uncoordinated transmissions often incur a number of duplicate packets, which are further forwarded in the network, occupy the limited network resource, and hinder the packet delivery performance. Existing solutions to this issue, e.g. overhearing or coordination based approaches, either cannot scale up with the system size, or suffers high control overhead. We present Duplicate-Detectable Opportunistic Forwarding (DOF), a duplicate free opportunistic forwarding protocol for low-duty-cycled wireless sensor networks. DOF enables senders to obtain the information of all potential forwarders via a slotted acknowledgement scheme, so the data packets can be sent to the deterministic next-hop forwarder. Based on light-weight coordination, DOF explores the opportunities as many as possible and removes duplicate packets from the forwarding process. We implement DOF and evaluate its performance on an indoor test-bed with 20 TelosB nodes. The experimental results show that DOF reduces the average duplicate ratio by 90%, compared to state-of-the-art opportunistic protocols, and achieves 61.5% enhancement in network yield and 51.4% saving in energy consumption.
【Keywords】: Routing; Probes; Protocols; Measurement; Load modeling; System performance; Wireless sensor networks
【Paper Link】 【Pages】:1-10
【Authors】: Yi Gao ; Wei Dong ; Chun Chen ; Jiajun Bu ; Gaoyang Guan ; Xuefeng Zhang ; Xue Liu
【Abstract】: In wireless sensor networks, sensor nodes are usually self-organized, delivering data to a central sink in a multi-hop manner. Reconstructing the per-packet routing path enables fine-grained diagnostic analysis and performance optimizations of the network. The performances of existing path reconstruction approaches, however, degrade rapidly in large scale networks with lossy links. In this paper, we propose Pathfinder, a robust path reconstruction method against packet losses as well as routing dynamics. At the node side, Pathfinder exploits temporal correlation between a set of packet paths and efficiently compresses the path information using path difference. At the PC side, Pathfinder infers packet paths from the compressed information and employs intelligent path speculation to reconstruct the packet paths with high reconstruction ratio. We evaluate several variations of Pathfinder as well as two most related approaches using traces from a large scale deployment and extensive simulations. Results show that Pathfinder outperforms existing approaches, achieving both high reconstruction ratio and low transmission overhead.
【Keywords】: Routing; Vectors; Containers; Packet loss; Encoding; Wireless sensor networks
【Paper Link】 【Pages】:1-10
【Authors】: Zi Li ; Yang Peng ; Daji Qiao ; Wensheng Zhang
【Abstract】: This paper proposes JAM, a Joint Aggregation and MAC design, to improve the sensor network lifetime under the end-to-end delay constraint. The key idea is to adjust both network traffic (via data aggregation) and communication overhead (via duty-cycled MAC) in a holistic manner at each individual node as well as between neighbors. As a result, JAM extends the sensor network lifetime more efficiently and effectively than the state-of-the-art solutions while guaranteeing the desired delay bound and achieving a lower level of average nodal power consumption. JAM is a lightweight and distributed solution with limited control information exchanged between neighbors only, which makes it deployable in practical sensor networks. Extensive ns-2 simulation and TinyOS experiment results are used to demonstrate the effectiveness of JAM in prolonging the network lifetime.
【Keywords】: Delays; Media Access Protocol; Equations; Kernel; Receivers; Energy consumption
【Paper Link】 【Pages】:1-11
【Authors】: Zhi Zhang ; Yigal Bejerano ; Spyridon Antonakopoulos
【Abstract】: We consider the problem of minimizing the power consumption of IP core networks by means of power-aware design and auto-configuration of the Points of Presence (PoPs), given general traffic demands on the links. Although the problem is in general NP-complete, we give an optimal algorithm for an important variant in which the number of ports on each line-card chassis is 2. For the general problem, we design two approximation algorithms with respective P=2 and 2 lnN approximation ratios, where P is the number of ports on each line-card chassis, and N is the number of chassis within the PoP. When the traffic demands are correlated, we prove that our algorithms are optimal. Extensive simulations demonstrate that our PoP design and auto-configuration algorithms significantly outperform existing design solutions over a wide range of traffic instances.
【Keywords】: Power demand; Algorithm design and analysis; IP networks; Approximation algorithms; Ports (Computers); Energy consumption; Switches
【Paper Link】 【Pages】:1-10
【Authors】: Berk Birand ; Howard Wang ; Keren Bergman ; Daniel C. Kilper ; Thyaga Nandagopal ; Gil Zussman
【Abstract】: Core and aggregation optical networks are remarkably static, despite the emerging dynamic capabilities of the individual optical devices. This stems from the inability to address optical impairments in real-time. As a result, tasks such as adding and removing wavelengths take a substantial amount of time, and therefore, optical networks are over-provisioned and inefficient in terms of capacity and energy. Optical Performance Monitors (OPMs) that assess the Quality of Transmission (QoT) in real-time can be used to overcome these inefficiencies. However, prior work mostly focused on the single link level. In this paper, we present a network-wide optimization algorithm that leverages OPM measurements to dynamically control the wavelengths' power levels. Hence, it allows adding and dropping wavelengths quickly while mitigating the impacts of impairments caused by these actions, thereby facilitating efficient operation of higher layer protocols. We evaluate the algorithm's performance using a network-scale optical simulator under real-world scenarios and show that the ability to add and drop wavelengths dynamically can lead to significant power savings. Moreover, we experimentally evaluate the algorithm in an optical testbed and discuss the practical implementation issues. To the best of our knowledge, this paper is the first attempt at providing a global power control algorithm that uses live OPM measurements to enable dynamic optical networking.
【Keywords】: performance evaluation; Optical networks; network management; power control algorithms
【Paper Link】 【Pages】:1-10
【Authors】: Karthikeyan Sundaresan ; Sampath Rangarajan
【Abstract】: Carrier aggregation (CA) is an important feature of next generation cellular networks (LTE-advanced, LTE-A) that allows its users to aggregate upto 100 MHz of (dis-)contiguous spectral chunks to provide increased data rates. While the conventional approach of allowing LTE-A users to be configured on all component carriers, results in maximum diversity gain for scheduling, it also increases the users' power consumption and processing that scale with the number of component carriers. In light of the growing need to minimize energy consumption on mobile devices, we argue that it is possible to operate the LTE-A users on a small subset of component carriers to reduce their energy consumption, without any appreciable loss to the scheduling gain. A key step in realizing this goal however, is to address the joint problem of component carrier selection as well as scheduling and in turn forms the focus of this work. We highlight the hardness of the joint problem when the number of component carriers that can be activated for an LTE-A user is limited. Towards solving the problem, we consider various models that incorporate both contiguous and dis-contiguous CA as well as backlogged and finite user buffers and propose efficient, greedy algorithms with performance guarantees that are also simple to implement. Our evaluations based on LTE system parameters, reveal that our algorithms help realize 80-90% of the maximum scheduling gain with just half the component carriers and provide a 25% throughput gain over baseline load and signal power based carrier selection schemes.
【Keywords】: Resource management; Schedules; Joints; Power demand; Throughput; Next generation networking; Aggregates
【Paper Link】 【Pages】:1-10
【Authors】: Ioannis Pefkianakis ; Chi-Yu Li ; Chunyi Peng ; Suk-Bok Lee ; Songwu Lu
【Abstract】: This work experimentally studies the energy consumption of multiple-antenna MIMO 802.11 devices. Our measurements reveal an increase in power consumption and speed with the number of antennas. State of the art proposals have limitations to save energy in MIMO 802.11 networks. First, they focus on either maximizing speed or minimizing power consumption. Second, they only seek to minimize energy for the receiver side of mobile devices. As a result, they present limitations to utilize MIMO speed gains and to save energy in MIMO 802.11 infrastructure. To this end, we design Collaborative MIMO Energy Save (CMES), which seeks to identify the transmitter-receiver most energy efficient antenna setting, at runtime. Our experiments with commodity MIMO 802.11n testbeds confirm that CMES can provide energy savings in real scenarios.
【Keywords】: MIMO; Power demand; Receivers; IEEE 802.11n Standard; Energy consumption; Transmitters
【Paper Link】 【Pages】:1-10
【Authors】: Xi Tao ; Yan Qiao ; Jih-Kwon Peir ; Shigang Chen ; Zhuo Huang ; Shih-Lien Lu
【Abstract】: The routing and packet forwarding function is at the core of the IP network-layer protocols. The throughput of a router is constrained by the speed at which the routing table lookup can be performed. Hash-based lookup has been a research focus in this area due to its O(1) average lookup time, as compared to other approachs such as trie-based lookup which tends to make more memory accesses. With a series of prior multi-hashing developments, including d-random, 2-left, and d-left, we discover that a new guided multi-hashing approach holds the promise of further pushing the envelope of this line of research to make significant performance improvement beyond what today's best technology can achieve. Our guided multi-hashing approach achieves near perfect load balance among hash buckets, while limiting the number of buckets to be probed for each key (address) lookup, where each bucket holds one or a few routing entries. Unlike the localized optimization by the prior approaches, we utilize the full information of multi-hash mapping from keys to hash buckets for global key-to-bucket assignment. We have dual objectives of lowering the bucket size while increasing empty buckets, which helps to reduce the number of buckets brought from off-chip memory to the network processor for each lookup. We introduce mechanisms to make sure that most lookups only require one bucket to be fetched. Our simulation results show that with the same number of hash functions, the guided multiple-hashing schemes are more balanced than d-left and others, while the average number of buckets to be accessed for each lookup is reduced by 20-50%.
【Keywords】: Arrays; Routing; Memory management; Indexes; Delays; Load management; Throughput
【Paper Link】 【Pages】:1-10
【Authors】: Seweryn Dynerowicz ; Timothy G. Griffin
【Abstract】: Most Internet routing protocols have one of two algorithms lurking at their core - either Dijkstra's algorithm in the case of link-state protocols or a distributed Bellman-Ford algorithm in the case of distance-vector or path-vector protocols. When computing simple shortest paths these protocols can be modified to utilize all best paths with a combination of next-hop sets and Equal Cost Multi-Path (ECMP) forwarding. We show that this picture breaks down even for simple modifications to the shortest path metric. This is illustrated with widest-shortest paths where among all shortest paths only those with greatest bandwidth are considered best. In this case Bellman-Ford and Dijkstra may compute different sets of paths and neither can compute all best paths. In addition, some paths computed by Dijkstra's algorithm cannot be implemented with next-hop forwarding. We provide a general algebraic model that helps to clarify such anomalies. This is accomplished by computing paths within the route metric rather than with specialized algorithmic extensions. Our results depend on the distinction between global and local optima that has hitherto been applied almost exclusively to more exotic routing protocols such as BGP.
【Keywords】: Measurement; Routing protocols; Equations; Internet; Routing; Mathematical model
【Paper Link】 【Pages】:1-10
【Authors】: Jiao Zhang ; Fengyuan Ren ; Li Tang ; Chuang Lin
【Abstract】: The TCP incast problem attracts a lot of attention due to its wide existence in cloud services and catastrophic performance degradation. Some effort has been made to solve it. However, the industry is still struggling with it, such as Facebook. Based on the investigation that the TCP incast problem is mainly caused by the TimeOuts (TOs) occurring at the boundary of the stripe units, this paper presents a simple and effective TCP enhanced mechanism, called GIP (Guarantee Important Packets), for the applications with the TCP incast problem. The main idea is making TCP aware of the boundaries of the stripe units, and reducing the congestion window of each flow at the start of each stripe unit as well as redundantly transmitting the last packet of each stripe unit. GIP modifies TCP a little at the end hosts, thus it can be easily implemented. Also, it poses no impact on the other TCP-based applications. The results of both experiments on our testbed and simulations on the ns-2 platform demonstrate that TCP with GIP can avoid almost all of the TOs and achieve high goodput for applications with the incast communication pattern.
【Keywords】: Redundant Transmission; Data Center Networks; TCP incast; Goodput; Initial Window
【Paper Link】 【Pages】:1-10
【Authors】: Wei Wang ; Baochun Li ; Ben Liang
【Abstract】: Middleboxes are widely deployed in today's enterprise networks. They perform a wide range of important network functions, including WAN optimizations, intrusion detection systems, network and application level firewalls, etc. Depending on the processing requirement of traffic, packet processing for different traffic flows may consume vastly different amounts of hardware resources (e.g., CPU and link bandwidth). Multi-resource fair queueing allows each traffic flow to receive a fair share of multiple middlebox resources. Previous schemes for multi-resource fair queueing, however, are expensive to implement at high speeds. Specifically, the time complexity to schedule a packet is O(log n), where n is the number of backlogged flows. In this paper, we design a new multi-resource fair queueing scheme that schedules packets in a way similar to Elastic Round Robin. Our scheme requires only O(1) work to schedule a packet and is simple enough to implement in practice. We show, both analytically and experimentally, that our queueing scheme achieves nearly perfect Dominant Resource Fairness.
【Keywords】: Middleboxes; Schedules; Bandwidth; Round robin; Radiation detectors; Time complexity; Algorithm design and analysis
【Paper Link】 【Pages】:1-10
【Authors】: Zhian Mi ; Tong Yang ; Jianyuan Lu ; Hao Wu ; Yi Wang ; Tian Pan ; Haoyu Song ; Bin Liu
【Abstract】: Network virtualization allows multiple virtual routers to coexist in the same physical router but offer independent routing services. Each virtual router needs to perform millions of lookups and thousands of updates per second to meet the requirements of high-speed Internet. The coexistence of these virtual routers intensifies scalability challenges to the routing lookup scheme: Can it scale well in storage, lookup speed and update performance as the number of virtual routers increases? In this paper, we propose Layer-based Overlay and Optimized Polymerization (LOOP) which has favorable scalability regardless of the number of virtual routers. Experiments on the general-purpose CPU show that LOOP achieves efficient storage, fast lookup, and fast incremental update. It compacts 18 FIBs with about 7M prefixes in total to only 4.6MB. One single thread can perform about 50M lookups per second on real-world traces. LOOP allows an update thread to run in parallel with lookup threads and barely interrupt them, and pure update testing indicates it can perform about 1M updates per second. One of the key advantages of LOOP is that it supports inserting and deleting virtual routers incrementally so it is ideal for fast and dynamic configuration of virtual networks.
【Keywords】: Routing; Arrays; Redundancy; Bridges; Buildings; Compaction
【Paper Link】 【Pages】:1-10
【Authors】: Enrique Mallada ; Xiaoqiao Meng ; Michel Hack ; Li Zhang ; Ao Tang
【Abstract】: This paper examines synchronization of computer clocks connected via a data network and proposes a skewless algorithm to synchronize them. Unlike existing solutions, which either estimate and compensate the frequency difference (skew) among clocks or introduce offset corrections that can generate jitter and possibly even backward jumps, our algorithm achieves synchronization without these problems. We first analyze the convergence property of the algorithm and provide necessary and sufficient conditions on the parameters to guarantee synchronization. We then implement our solution on a cluster of IBM BladeCenter servers running Linux and study its performance. In particular, both analytically and experimentally, we show that our algorithm can converge in the presence of timing loops. This marks a clear contrast with current standards such as NTP and PTP, where timing loops are specifically avoided. Furthermore, timing loops can even be beneficial in our scheme. For example, it is demonstrated that highly connected subnetworks can collectively outperform individual clients when the time source has large jitter. It is also experimentally demonstrated that our algorithm outperforms other well-established software-based solutions such as the NTPv4 and IBM Coordinated Cluster Time (IBM CCT).
【Keywords】: Synchronization; Protocols; Clocks; Estimation; Radiation detectors; Eigenvalues and eigenfunctions; Convergence
【Paper Link】 【Pages】:1-10
【Authors】: Muhammad Irfan Yousuf ; Suhyun Kim
【Abstract】: This paper discusses the design and evaluation of Kistree, a reliable, fault-tolerant and self-configuring constant degree distributed hash table (DHT) for peer-to-peer systems. The Kistree topology can be thought of as log(n) vertically stacked layers or levels. At each level, we divide the whole identifier space into segments to form an n-ary tree structure. The nodes and keys belong to a particular segment at a level in Kistree network depending on the node / key identifier. A node in Kistree contacts with a constant number of nodes at the next level to forward queries. A node also creates a link with a node at the topmost level to get a global view of the system. This way Kistree keeps a constant number of neighbors in the routing table and traverses a logarithmic number of nodes to route a query to its destination. An insert operation stores a key on a number of diverse nodes of a concerned segment. The lookup operation, on the other hand, retrieves a stored key efficiently and reliably. The prototype implementation of Kistree on PeerSim verifies its scalability, reliability and efficiency. The experimental results achieved with a network of 50,000 nodes confirm its self-configurability and ability to route messages even under a high rate of churn.
【Keywords】: Peer-to-peer computing; Routing; Fellows; Optimization; Redundancy; Joining processes
【Paper Link】 【Pages】:1-11
【Authors】: Hongkun Yang ; Simon S. Lam
【Abstract】: Network management will benefit from automated tools based upon formal methods. Several such tools have been published in the literature. We present a new formal method for a new tool, Atomic Predicates (AP) Verifier, which is much more time and space efficient than existing tools. Given a set of predicates representing packet filters, AP Verifier computes a set of atomic predicates, which is minimum and unique. The use of atomic predicates dramatically speeds up computation of network reachability. We evaluated the performance of AP Verifier using forwarding tables and ACLs from three large real networks. The atomic predicate sets of these networks were computed very quickly and their sizes are surprisingly small. Real networks are subject to dynamic state changes over time as a result of rule insertion and deletion by protocols and operators, failure and recovery of links and boxes, etc. In a software-defined network, the network state can be observed in real time and thus may be controlled in real time. AP Verifier includes algorithms to process such events and check compliance with network policies and properties in real time. We compare time and space costs of AP Verifier with NetPlumber using datasets from the real networks.
【Keywords】: Ports (Computers); Data structures; Boolean functions; Real-time systems; Educational institutions; IP networks; Protocols
【Paper Link】 【Pages】:1-10
【Authors】: Ying Zhang ; Neda Beheshti ; Ludovic Beliveau ; Geoffrey Lefebvre ; Ravi Manghirmalani ; Ramesh Mishra ; Ritun Patney ; Meral Shirazipour ; Ramesh Subrahmaniam ; Catherine Truchan ; Mallik Tatipamula
【Abstract】: Network operators are faced with the challenge of deploying and managing middleboxes (also called inline services) such as firewalls within their broadband access, datacenter or enterprise networks. Due to the lack of available protocols to route traffic through middleboxes, operators still rely on error-prone and complex low-level configurations to coerce traffic through the desired set of middleboxes. Built upon the recent software-defined networking (SDN) architecture and OpenFlow protocol, this paper proposes StEERING, short for SDN inlinE sERvices and forwardlNG. It is a scalable framework for dynamically routing traffic through any sequence of middleboxes. With simple centralized configuration, StEERING can explicitly steer different types of flows through the desired set of middleboxes, scaling at the level of per-subscriber and per-application policies. With its capability to support flexible routing, we further propose an algorithm to select the best locations for placing services, such that the performance is optimized. Overall, StEERING allows network operators to monetize their middlebox deployment in new ways by allowing subscribers flexibly to select available network services.
【Keywords】: Internet; Switches
【Paper Link】 【Pages】:1-10
【Authors】: Ahsan Arefin ; Raoul Rivas ; Rehana Tabassum ; Klara Nahrstedt
【Abstract】: Video conferencing applications pose fundamentally different service requirements than traditional data traffic on the Internet. Strong real-time interactivity is very important among participants unlike video streaming in VoD applications. Requirements are even more stringent in multi-stream and multi-site teleimmersive applications due to strong dependencies across geographically distributed streams. In this paper, we propose OpenSession, a cross-layer session-network control protocol for multi-stream multi-site 3D teleimmersion (3DTI) that improves interactivity, resource utilization and scalability. OpenSession decouples application layer data and control plane functionalities, and partially offloads the data plane functionalities to network layer switches. To control network layer switches during the session run-time, OpenSession leverages support from Software Defined Networking (e.g., OpenFlow). Through extensive evaluation with multi-stream 3D teleimmersion among four distributed sites and PlanetLab-based larger 3DTI setup, we show that OpenSession improves 3DTI interactivity and resource usage at the data plane. Furthermore, OpenSession keeps data plane robust against host failures and frequent route updates.
【Keywords】: Logic gates; Three-dimensional displays; Bandwidth; Topology; Control systems; IP networks; Ports (Computers)
【Paper Link】 【Pages】:1-2
【Authors】: Pradeep Bangera ; Sergey Gorinsky
【Abstract】: This paper presents an economic perspective on traffic attraction and countermeasures. The results demonstrate that tier-1, tier-2, and tier-3 networks have significant financial incentives to attract traffic. In comparison to ASes from the lower tiers, the tier-1 networks are in a stronger position to benefit from traffic attraction with respect to: (a) the degree of the attainable gain, (b) impact on other networks, and (c) preserving their own gain when multiple ASes attract traffic. The traffic attraction remains effective despite countermeasures unless other ASes participate in the countermeasures broadly. The disconnection by losing customers is ineffective unless a large portion of them terminate their business relationships with the attractor.
【Keywords】: Economics; Data models; Topology; Internet; Protocols; Pricing
【Paper Link】 【Pages】:1-2
【Authors】: Younghoon Kim ; Yusung Kim ; Ikjun Yeom
【Abstract】: This paper investigates the impact of large flows in Content Centric Networks (CCN). In CCN, routers have caches, and store all the data after forwarding. If large flows temporarily occupy a content cache, they may evict popular chunks from the cache, and it results in low cache hit ratio. We mathematically analyzed the amount of occupancy of a large flow in a cache, and realized that a few large flows can constitute a significant portion of a cache. Our simulation results showed that small flows experience cache hit ratio degradation as the number of large flows increases. Finally, we present that limiting the occupancy of large flows in a cache can effectively improve the cache hit ratios for small flows.
【Keywords】: Limiting; Electronic mail; Degradation; Bandwidth; Time factors; Educational institutions; Computer science
【Paper Link】 【Pages】:1-2
【Authors】: Lulu Dong ; Hua Li ; Nan He ; Yi Xing
【Abstract】: OpenFlow is a new protocol which enables researchers to run experimental protocols in a network without changing the network topology. In the paper, we analyze and test OpenFlow based on a formal method, such as CPN (colored Petri net). To avoid state exploration, we mainly focus on testing the interaction property of OpenFlow. According to the latest OpenFlow specification, we construct its hierarchy CPN model and analyze the model with CPN tools. We propose two methods to generate the test sequences covering the interaction property. We also design an algorithm to generate the test sequences automatically. The related experiments are carefully designed and executed in four kinds of network environment, respectively.
【Keywords】: Switches; Protocols; Network topology; Testing; Internet; Topology
【Paper Link】 【Pages】:1-2
【Authors】: Jan Pieter Meijers ; Marica Amadeo ; Claudia Campolo ; Antonella Molinaro ; Stefano Yuri Paratore ; Giuseppe Ruggeri ; Marthinus J. Booysen
【Abstract】: Content-Centric Networking (CCN) provides a complete communication framework for data retrieval and dissemination. It leverages innovative naming, security schemes and novel routing strategies, augmented with caching at intermediate nodes. Content requests are forwarded towards the source(s) by direct use of content names (instead of IP addresses), matching the layout of the Wireless Sensor Network. Despite its potential CCN can not be directly applied to wireless environments, specifically resource-constrained sensor nodes. In this paper, a two-tier CCN architecture is proposed to manage the heterogeneity of involved devices (remote server, sink, sensor nodes). CCN is enhanced with some changes to the forwarding strategies to improve data collection.
【Keywords】: Wireless Sensor Networks; Content-Centric Networking
【Paper Link】 【Pages】:1-2
【Authors】: Pili Hu ; Wing Cheong Lau
【Abstract】: Decentralized Social Network (DSN) has attracted a lot of research and development interest in recent years. It is believed to be the solution to many problems of centralized services. Due to the data limitation imposed by common decentralized architectures, centralized algorithms that support social networking functions need to be re-designed. In this work, we tackle the problem of community detection for a given user under the constraint of limited local topology information. This naturally yields a classification formulation for community detection. As an initial study, we focus on a specific type of classifiers - classification by thresholding against a proximity measure between nodes. We investigated four proximity measures: Common Neighbours (CN), Adamic/Adar score (AA), Page Rank (PR), Personalized PageRank (PPR). Using data collected from a large-scale Social Networking Service (SNS) in practice, we show that PPR can outperform the others with a few pre-known labels (37.5% to 64.97% relative improvement in terms of Area Under the ROC Curve). We further carry out extensive numerical evaluation of PPR, showing that more pre-known labels can linearly increase the capability of the single-feature classifier based on PPR. Users can thus seek for a trade-off between labeling cost and classification accuracy.
【Keywords】: Communities; Observers; Social network services; Topology; Network topology; Accuracy; Servers
【Paper Link】 【Pages】:1-2
【Authors】: Yurino Sato ; Hiroyuki Koga ; Masayoshi Shimamura ; Takeshi Ikenaga
【Abstract】: Packet losses significantly degrade TCP performance in high latency networks. To improve TCP performance in such networks, we proposed two methods to suppress the return of duplicate ACKs and to control minimum redundancy because FEC technology cannot work effectively when simply applied to TCP operation. Simulation evaluations show that the proposed methods enable higher throughput than the conventional methods, especially in high latency environments. In our future work, we will consider a scheme to more appropriately determine the appropriate redundancy level for network conditions and to more effectively recover lost packets in a real environment, such as where burst packet losses occur.
【Keywords】: Redundancy; Forward error correction; Packet loss; Throughput; Delays; Receivers
【Paper Link】 【Pages】:1-2
【Authors】: Guang Yao ; Jun Bi ; Luyi Guo
【Abstract】: In this paper, a potential threat to reliability of Software Defined Networking (SDN) is disclosed: the cascading failures of controllers. Current SDN designs have widely utilized multiple controllers and the load of a failed controller can be redistributed to the other controllers. However, simply utilizing multiple controllers cannot protect SDN networks from a single point of failure: the load of the controllers which carry the load of the failed controller can exceed the capacity of them, and then cascading failures of controllers will happen. In this article, at first we propose a model for such failures and present simulation results based on the model. Strategies for initial load balance and load redistribution after failure are designed to prevent such failures. The simulation result shows the strategies can significantly increase the resistance of SDN networks to cascading failures.
【Keywords】: software defined network; cascading failure
【Paper Link】 【Pages】:1-2
【Authors】: Matthieu Coudron ; Stefano Secci ; Guy Pujolle
【Abstract】: Cloud networking imposes new requirements in terms of connection resiliency and throughput among virtual machines, hypervisors and users. A promising direction is to resort to multipath communications, yet existing protocols still struggle to take advantage of the path diversity offered by IP networks. Multipath TCP (MPTCP) can create several TCP subflows on different interfaces and concurrently forward data on these subflows. Current MPTCP implementations create a full mesh of subflows between IP endhosts, which may be suboptimal according to the topology. We propose to rely on topology information brought by an external protocol in order to improve the MPTCP subflow management; we resort to the Locator/Identifier Separation Protocol (LISP) to retrieve IP path diversity information, to then accordingly create MPTCP subflows. We report noticeable benefits obtained using a large-scale Cloud access test bed, and we describe further work we are conducting in this sense.
【Keywords】: IP networks; Protocols; Wide area networks; Topology; Ports (Computers); Throughput; Network topology
【Paper Link】 【Pages】:1-2
【Authors】: Andrew Reed ; Jay Aikat
【Abstract】: As HTTP-based streaming video applications have grown to become a major source of Internet traffic, and as the new ISO standard Dynamic Adaptive Streaming over HTTP (DASH) gains industry acceptance, researchers need the ability to both study real-world viewing data and simulate realistic DASH streams. The first effort is complicated by the fact that network researchers are often restricted to anonymized, header-only traces. The second effort is difficult since researchers are currently limited to three undesirable options for generating DASH traffic: (1) encode and store movies, which is both labor-and storage-intensive, (2) parameterize DASH traffic, which is open to criticism, or (3) stream movies from a service such as Netflix, which is prohibitively expensive if a researcher wants to simulate many simultaneous viewers. In this paper we present our work towards developing a model for DASH traffic and show how the model can be applied to identify DASH streams from anonymized, header-only traces using a combination of Hadoop and Hive. We then describe how the insight gained from our work will be used in a simulator that can recreate the DASH payloads of real movies using a format that requires only a few kilobytes of storage per movie.
【Keywords】: Content distribution networks; Internet; Streaming media; Data analysis; Computer simulation
【Paper Link】 【Pages】:1-2
【Authors】: Dan Wu ; Zhiliang Wang ; Xia Yin ; Xingang Shi ; Jianping Wu ; Min Huang
【Abstract】: Nowadays, the global routing system suffers from great scalability problem. Core/edge separation solutions are proposed to solve the problem. However, they bring a global mapping system which might also suffer from scalability problem. We come up with an idea to reduce the necessary routing or mapping information, which is to separate content provider networks (containing content providers) from content consumer networks (containing only content consumers) and remove the routing or mapping information of content consumer networks. We combine this idea with core/edge separation solutions to reduce the necessary information in the global mapping system.
【Keywords】: Servers; Routing; Scalability; Internet; IP networks; Encapsulation; Peer-to-peer computing
【Paper Link】 【Pages】:1-2
【Authors】: Ahsan Arefin ; Klara Nahrstedt
【Abstract】: Software Defined Networking (SDN) has provided configurable access to remote network layer components from application hosts during application run-time. We have successfully enabled SDN switches to reduce network resource consumption and improve streaming latency in multi-party 3D tele-immersive (3DTI) applications. Instead of forwarding the same streams to multiple participants from the application host, local network switches replicate network packets towards multiple forwarding paths. However, due to the variable length of application frames generated from the 3DTI application, maintaining constant packet rates at the network switches cannot guarantee required application frame rates towards different forwarding paths. In this poster, we investigate the problem of guaranteeing application frame rates from the network layer switches. We formulate the problem and sketch a scalable solution using OpenFlow, which is a standard protocol developed for SDN.
【Keywords】: Three-dimensional displays; Quality of service; Logic gates; Cameras; Streaming media; Bandwidth; Switches
【Paper Link】 【Pages】:1-2
【Authors】: Yu Cao ; Mingwei Xu
【Abstract】: Multipath TCP (MPTCP) can significantly improve the performance of bulk data transfer in Data Center Networks (DCNs). To achieve this, an MPTCP flow wants each of its subflows to run on a different under-utilized path. Existing routing schemes fail to meet this requirement. we propose to dynamically construct disjoint paths for each MPTCP flow so as to fully utilize the path diversity of DCNs to achieve high data transfer performance. The simulations show that, compared to current practice, our scheme can increase goodputs by more than 60%.
【Keywords】: Ports (Computers); Data transfer; Dynamic scheduling; Routing; Oscillators; Network address translation
【Paper Link】 【Pages】:1-2
【Authors】: David Koll ; Jun Li ; Joshua Stein ; Xiaoming Fu
【Abstract】: A Sybil attack can inject many forged identities (called Sybils) to subvert a target system. Among various defense approaches, of particular attention are those that explore the online social networks (OSNs) of users in a target system to detect or tolerate Sybil nodes. Albeit different in their working principle, all these approaches assume it is difficult for an attacker to create attack edges to connect Sybils with honest users. However, researchers have found that an attacker can employ simple strategies to obtain many attack edges. In this work we revisit the state-of-the-art, OSN-based Sybil defenses, and point out their strengths and weaknesses due to the impact of the new properties. We find these defense approaches are vulnerable to attackers under the new scenario, and in many cases a Sybil node only needs to obtain a handful of attack edges to disguise itself as a benign node.
【Keywords】: Image edge detection; Educational institutions; Communities; Face; Facebook; Joining processes
【Paper Link】 【Pages】:1-2
【Authors】: Takeo Ogawara ; Yoshihiro Kawahara ; Tohru Asami
【Abstract】: In this poster, we propose an authentication system, especially registration procedure, that can be used before and after a disaster. Using a two-tier HIDE, distributed authentications are done within each disrupted network segment without changing any user interface. To share the encrypted data among the users of this application at (8) of II-C, other types of encryption schemes are required. Attribute Base Encryption is one of these candidates and can be used as a smooth extension of the procedure described in this poster[7]. An actual implementation must be produced using an appropriate toolkit such as CCNx to evaluate the performance. This will be performed in future research. The work for this paper was performed in the context of the FP7/NICT EU-JAPAN GreenICN project.
【Keywords】: Authentication; Base stations; Servers; Encryption; Identity-based encryption
【Paper Link】 【Pages】:1-2
【Authors】: Haiyong Xie ; Yanhua Li ; Jin Wang ; Diego R. Lopez ; Tina Tsou ; Yonggang Wen
【Abstract】: It has been a significant challenge for network carriers to deploy and provision a large number of Customer-Premises Equipment (CPE) devices located at subscribers' premises and connected to a carrier's network infrastructure. In this paper, we make a first systematic attempt to fundamentally re-shape the access networks into a software defined networking architecture by virtualizing the network functionality of residential gateways (vRGW). Our approach can be generalized to other CPE such as set-top boxes. Our analysis suggests that vRGW can achieve significant economic benefits ranging from up to 90% reduction on the call center cost and up to 46% reduction on the product return cost.
【Keywords】: Logic gates; Software; Computer architecture; Home automation; Throughput; Wide area networks; Virtualization
【Paper Link】 【Pages】:1-2
【Authors】: Vitaly Petrov ; Maria Komar ; Yevgeni Koucheryavy
【Abstract】: In this paper the lightweight many-to-many authentication protocol, that uses Near Field Communications as a carrier technology is proposed. The solution works without any user interaction and can be applied for almost any data storage device: NFC or RFID tag, USB-flash drive, etc. The major novelty of the system is real-time encryption key generation algorithm. This approach doesn't require any computation power on the tag, trusted third parties or secure link between tag and information system. So far, the mentioned features transforms to significant advantages of the proposed solution, while compared to existing analogues: OAuth, Opacity and LMAP. At the same time, the integrity of key sequences is not guarantied, that brings motivation for future research in the field.
【Keywords】: Authentication; Protocols; Encryption; Radiofrequency identification; Usability
【Paper Link】 【Pages】:1-2
【Authors】: Markus Vahlenkamp ; Fabian Schneider ; Dirk Kutscher ; Jan Seedorf
【Abstract】: In this work, we outline how to enable Information-Centric Networking (ICN) on existing IP networks, such as ISP or data center networks, using Software-Defined Networking (SDN) functions and control. We describe a mechanism that requires neither new or extended network/L3 and transport/L4 protocols nor changes of ICN host network stacks, and supports aggregation of routes inside the SDN controlled network. The proposed solution is agnostic of the specific ICN protocol in use, and does not require all network elements to be SDN-enabled. It supports advanced ICN routing features like request aggregation and forking, as well as load-balancing, traffic engineering, and explicit path steering (e. g., through ICN caches). We present the design as well as our first implementation of the proposed scheme-based on the Trema OpenFlow controller-framework and CCNx.
【Keywords】: IP networks; Protocols; Ports (Computers); Routing; Network topology; Europe; Control systems
【Paper Link】 【Pages】:1-2
【Authors】: Xiangming Zhu ; Yong Li ; Depeng Jin ; Pan Hui
【Abstract】: Understanding and characterizing the properties of vehicular networks has become hugely important because of their wide applications and fast development. Due to the unique property of vehicular networks that nodes change their locations at high speed in anytime, their connectivity is an important and unique property. In this poster, based on realistic vehicular mobility traces, we reveal the opportunistic connectivity property of large-scale urban vehicular networks. Moreover, through analysis, we unveil the fundamental relationships and tradeoffs between the opportunistic connectivity and network parameters in terms of data size, delivery delay, transmission energy, etc.
【Keywords】: Delays; Educational institutions; Collaboration; Laboratories; Information science; Computer science; Electronic mail
【Paper Link】 【Pages】:1-2
【Authors】: Zhaogeng Li ; Jun Bi ; Sen Wang
【Abstract】: CCN is one of the future Internet architecture. However, the lack of real traffic becomes an obstacle to advanced CCN researches. HTTP, as an content-oriented application-layer protocol working over current Internet, is similar to CCN in many aspects. In this demo, we try to convert HTTP traffic into CCN traffic with HTTP-CCN gateway. Although HTTP is not equivalent to CCN, we can design carefully to make the conversion correct in most situations. The gateway will introduce real traffic into CCN testbed to support CCN researches. Our demonstration will show how to use this gateway.
【Keywords】: Gateway; CCN; HTTP
【Paper Link】 【Pages】:1-2
【Authors】: Christian Vogt ; Max Jonas Werner ; Thomas C. Schmidt
【Abstract】: WebRTC enables web applications to establish a direct communication channel between two browsers without relaying the data through a web server. It consists of an API [1] defined by the W3C and a set of underlying protocols defined by the IETF Rtcweb Working Group [2]. The possibility of establishing peer-to-peer channels between two browsers and the expected broad deployment opens the opportunity for new use cases that were not possible until now.
【Keywords】: Browsers; Peer-to-peer computing; Servers; Routing; Protocols; Emulation; Buildings
【Paper Link】 【Pages】:1-2
【Authors】: Jiachen Chen ; Mayutan Arumaithurai ; Xiaoming Fu ; K. K. Ramakrishnan
【Abstract】: This work demonstrates the benefit brought by COPSS for an efficient notification service, including the convenience of hierarchical group management, network efficiency and timeliness in delivering the notification. The work will also demonstrate a simple first-step authorization. Future work will include a more complete authorization, authentication, encryption and mobility support for a scalable notification service.
【Keywords】: Authorization; Servers; Topology; Electronic mail; Cellular phones; Context; Disaster management
【Paper Link】 【Pages】:1-3
【Authors】: Fabian Kaup ; David Hausheer
【Abstract】: The increased availability and data rates of cellular 3G/4G networks combined with the growing use of mobile applications highly affect the Quality of Experience (QoE) perceived by the end-user. The QoE is affected in two ways: First, the data rates in the networks are low when multiple users simultaneously request content; second, the transmission of data over slow connections consumes a considerable amount of energy compared to faster connections. Both can be avoided by better management of the available resources. This paper proposes a new approach, taking the energy efficiency into account as a key QoE aspect. Based on user mobility models, the available connectivity can be predicted, from which estimates for the energy consumption and expected QoE can be derived. An architecture is sketched, which combines QoE prediction for current and future network connections with energy efficiency on mobile devices.
【Keywords】: Mobile communication; Quality of service; Mobile handsets; IEEE 802.11 Standards; Mobile computing; Energy consumption; Predictive models
【Paper Link】 【Pages】:1-3
【Authors】: Jiaqiang Liu ; Depeng Jin
【Abstract】: Despite of various benefits such as load balance and energy saving virtual machine (VM) migration promises to provide, its application in realistic data centers is still limited due to the limitation of migration in the LAN environment and the unpredictable performance. Through separation of control plane and data plane, software defined network (SDN) provides the possibility for an alternate solution to overcome these limitations. In this work, we aim at designing and implementing a software defined approach for live VM migration to experiment the possibility. This paper presents the key challenges and our preliminary design result to address these challenges.
【Keywords】: Routing; IP networks; Internet; Control systems; Logic gates; Software; Virtual machining
【Paper Link】 【Pages】:1-3
【Authors】: Luwei Cheng
【Abstract】: Cloud datacenters are increasingly adopting virtual machines (VMs) to provide elastic cloud services, with TCP being prevalently used for congestion control. In virtualized datacenters, the delays from the hypervisor scheduler can heavily contaminate RTTs sensed by VM senders, preventing TCP from correctly learning the physical network condition. In this dissertation, my direction is to paravirtualize the transport-layer protocol in the guest OS, making it automatically tolerate the virtualized running environment. I then present a preliminary solution, PVTCP, to overcome the distorted congestion information caused by VM scheduling delays.
【Keywords】: Delays; Receivers; Virtual machine monitors; Throughput; Wireless communication; Ad hoc networks; Switches
【Paper Link】 【Pages】:1-3
【Authors】: Simon Jouet ; Dimitrios P. Pezaros
【Abstract】: TCP congestion control has been a native part of all modern Operating System implementations where parameters are initialized assuming an underlying high Bandwidth Delay Product (BDP) environment. However, the significantly lower BDP in Data Centre (DC) networks makes such conservative transport-layer parameters together with deep-buffered switches and bursty traffic a factor of performance degradation, eventually leading to throughput incast collapse. In this paper, we propose a Software Defined Networking (SDN) approach to tune TCP initial window and retransmission timers for newly created flows based on a network-wide view created by aggregating known characteristics and temporal measurements at a central controller. Through simulation, we show the detrimental effect static TCP parameters have on mice flows and demonstrate the benefits of network-aware per-flow tuning. We show that the average latency under bursty traffic can be improved by a factor of eight, and that flow start and completion times can be improved by a factor of two and five, respectively.
【Keywords】: Throughput; Tuning; Mice; Delays; Bandwidth; Cloud computing
【Paper Link】 【Pages】:1-3
【Authors】: Muhammad Zeeshan ; Anjum Naveed
【Abstract】: Accurate modeling of the effects of interference on network capacity in two flow topologies is very critical in understanding MAC behaviors and predicting per flow throughput in general multi-hop wireless mesh networks. This understanding is helpful in designing efficient routing and spectrum decision protocols for WMNs. The existing interference models do not consider the difference between carrier sensing and transmission range while considering interfering links. In practical scenarios, links inside carrier sensing range of edge nodes of a particular link induce significantly different interference compared to links within transmission range. In this research, we have classified interference between two flow topologies on the basis of geometric location of the links within transmission and carrier sensing ranges. We have also considered the difference in MAC behavior and resulting throughput imbalances. We compute occurrence probabilities of identified categories and discuss the effect of MAC behavior on throughput imbalances. Subsequent work shall focus on interference model for multi-hop WMN based on our two-flow classification and prediction of per flow throughput in a general multi-hop WMNs.
【Keywords】: transmission range (TR); wireless mesh network (WMN); interference and capacity analysis; MAC behaviour; carrier sensing range (CSR)
【Paper Link】 【Pages】:1-3
【Authors】: Huanle Xu ; Wing Cheong Lau
【Abstract】: The MapReduce paradigm is now the de facto standard for large-scale data analytics. In this paper we address the resource management issues in MapReduce Cluster. Speculative execution (task backup) plays an important role in resource management. We propose two different strategies and build two models to formulate the backup issue as an optimization problem when the cluster is lightly loaded. Moreover, we present an Enhanced Speculative Execution (ESE) algorithm when the cluster is heavily loaded and adopt the approximate analysis to get an optimal value for the parameter in the algorithm. The simulation results show that the algorithm can reduce the job completion time by 50% while consuming much less resource compared to the naive method without backup.
【Keywords】: theoretical analysis; MapReduce; job scheduling; speculative execution
【Paper Link】 【Pages】:1-3
【Authors】: Yury Jimenez ; Cristina Cervello-Pastor ; Aurelio J. Garcia
【Abstract】: This work proposes an algorithm called k-Critical to solve the controller placement problem in Software Defined Networks. K-Critical finds the minimum number of controllers to satisfy a target communication delay between controllers and nodes, Dreq. In addition, the controllers selected create a management architecture that improves the subjacent network performance. In this work we focus on the controllers selection procedure, and show the desired management architecture characteristics that optimize the control and management of the network. The results show that our management trees balance the load among them and reduce the data loss.
【Keywords】: management tree; Controller placement problem; Software Defined Networks; management architecture
【Paper Link】 【Pages】:1-3
【Authors】: René Hummen ; Klaus Wehrle
【Abstract】: Peer authentication and secure data transmission are vital aspects for many scenarios in the IP-based Internet of Things (IoT). To enable end-to-end security, recent research and standardization efforts focus on a number of IP security protocol variants for the IoT, most notably Datagram TLS (DTLS), the HIP Diet EXchange (DEX), and minimal IKEv2. In this dissertation outline, we present the main motivation for employing these protocol variants in constrained network environments and discuss the need to surpass the status quo. Most importantly, we highlight our identified challenges when employing these protocol variants in constrained network environments and provide a high-level overview of our previously proposed approaches to counteract the identified design-level protocol issues.
【Keywords】: Protocols; Hip; IP networks; Internet; Authentication; Logic gates
【Paper Link】 【Pages】:1-3
【Authors】: Michael Finsterbusch ; Jean-Alexander Muller
【Abstract】: Internet traffic identification and validation has been the subject of intensive study for many years. It is used to provide Quality of Service, to provide security and to implement many other tasks. The reliability of these methods, however, is not proved by formal verification. Therefore, the results of these methods can vary from the lab where these methods were developed and their deployment in real world application. In this paper, we present an idea to overcome this problem in order to guarantee reliability and provide more optimised solutions.
【Keywords】: protocol verification; traffic identification
【Paper Link】 【Pages】:1-3
【Authors】: Qian Li
【Abstract】: Cognitive radios are recommended by FCC as a countermeasure against spectrum scarcity and inefficient utilization of spectrum. A cognitive radio can opportunistically use temporally or spatially unused wireless channels allocated to other licensees to transmit data. In a multi-hop cognitive radio network, channel assignment is accomplished by routing protocols. Classical routing protocols are not suitable for cognitive radio networks, because they are unaware of spectrum opportunities. Existing spectrum aware routing protocols were designed with different objectives. Based on our survey, there still lacks a competent routing protocol for large scale heterogeneous hybrid cognitive radio mesh networks, which are the most fitting network substrate for intelligent environment applications, such as smart cities. In this paper, we propose GCM - a Geographic routing protocol for large scale heterogeneous hybrid Cognitive radio Mesh networks. GCM is a multi-objective routing protocol that is aware of spectrum, energy, load, and link quality.
【Keywords】: Mesh Networks; Routing Protocols; Geographic Routing; Cognitive Radio Networks
【Paper Link】 【Pages】:1-3
【Authors】: Sabri-E. Zaman ; Raul J. Mondragón
【Abstract】: This paper shows that end to end traffic flows in a network that pass through disjoint paths affect each other. We refer to this as transitive relationship between traffic flows. We measure interdependencies among network elements by traffic correlation which leads to this transitive relationship between traffic flows. We show that the effect of transitive relationship becomes significant under certain congestion states in the network. This means that a problem might be present at a subset in the network but it's affect will be visible somewhere else. We also show that special care has to be taken while collecting flow data (for cross correlation) considering the delay distribution of traffic flows.
【Keywords】: Correlation; Delays; Intellectual property; Quality of service; Network topology; Educational institutions; Protocols
【Paper Link】 【Pages】:1-3
【Authors】: Christian Vogt ; Max Jonas Werner ; Thomas C. Schmidt
【Abstract】: Users eager to publish content on the Web need to either set up a server or use third-party infrastructure. However, the increasing desire to use the Web as a sharing platform for content demands solutions that counter disadvantages of centralized or restricted platforms. Recent efforts are underway at the IETF and W3C to standardize WebRTC for direct browser-to-browser communication. This paper introduces BOPlish, an infrastructure-independent naming and content access architecture for sharing information in User Networks. We demonstrate how BOPlish leveragesWebRTC for an easy to use, secure content publishing solution. A custom URI scheme serves as a location-independent addressing mechanism to separate publishing and content retrieval from the underlying infrastructure.
【Keywords】: Browsers; Peer-to-peer computing; Publishing; Servers; Cryptography; Protocols
【Paper Link】 【Pages】:1-3
【Authors】: Ting Bi ; Ramona Trestian ; Gabriel-Miro Muntean
【Abstract】: In the current telecommunication environment, network operators are trying to cope with a significant increase in data traffic by adopting different solutions to expand their network capacity. One of these solutions is the convergence of next generation wireless networks (e.g., HSDPA, LTE and WiMAX) which involve closely interworking of existing 2G/2.5G/3G networks with the new next generation networks in terms of handover and network selection. However, the diversification in mobile devices and the heterogeneity of the wireless environment make the seamless always best connectivity of mobile users a challenge for the service providers. We propose RLoad, a novel Reputation-based Load-balancing Network Selection Strategy for heterogeneous wireless environments, built on top of the IEEE 802.21 Media Independent Handover (MIH) standard. The proposed solution makes use of a reputation-based mechanism to select the most appropriate set of networks for the mobile user and a load balancing mechanism to distribute the traffic load among the networks by making use of the Multipath TCP (MPTCP) protocol. Preliminary simulation results show significant benefits when using the proposed RLoad solution.
【Keywords】: reputation mechanism; network selection solution; heterogeneous wireless network; MIH; MPTCP
【Paper Link】 【Pages】:1-3
【Authors】: Dan Ma ; Jinsong Han ; Zhi Wang
【Abstract】: In this paper, we develop novel physical-layer identification schemes for passive Radio Frequency IDentification (RFID) tags. Due to the collision among tags, existing RFID systems suffer from a low identification efficiency. In this paper, we propose to use the unique physical-layer information of tags as the identification basis. We design a batch identification scheme for passive tags. Our Scheme can fully utilize the collided signals to achieve efficient and trustworthy identification. Leveraging collided signals, we also propose an AoA-based spatial identification scheme for providing location service. Our scheme are seamlessly compatible with commercial off-the-shelf RFID devices. The initial result shows the feasibility of our proposals.
【Keywords】: Radiofrequency identification; Arrays; Feature extraction; Wireless communication; Antenna arrays; Educational institutions; Protocols
【Paper Link】 【Pages】:1-3
【Authors】: Hongkun Yang
【Abstract】: Network management will benefit from automated tools based upon formal methods. Several such tools have been published in the literature. We present a new formal method for a new tool, Atomic Predicates (AP) Verifier, which is much more time and space efficient than existing tools. Given a set of predicates representing packet filters, AP Verifier computes a set of atomic predicates, which is minimum and unique. We evaluated the performance of AP Verifier using forwarding tables and ACLs from three large real networks. The atomic predicate sets of these networks were computed very quickly and their sizes are surprisingly small. The use of atomic predicates dramatically speeds up computation of network reachability. On the average, AP Verifier is 3 orders of magnitude faster than an existing tool, Hassel in C. It also uses 2 to 3 orders of magnitude less memory than Hassel in C.
【Keywords】: Ports (Computers); Memory management; Educational institutions; Reachability analysis; Algorithm design and analysis; Real-time systems; Equations
【Paper Link】 【Pages】:1-3
【Authors】: Xiaoyan Hu ; Jian Gong
【Abstract】: This work proposes a scheme to promote autonomous and selfish NDN (Named Data Networking) peering domains to cooperate in caching, here dubbed Not So Cooperative Caching (NSCC). We consider a network comprised of selfish nodes; each is with a caching capability and an objective of reducing its own access cost by fetching data from local cache or from neighboring caches. The challenge is to determine what objects to cache at each node so as to induce low individual node access costs, and the realistic access “price” model which allows various access “prices” of different node pairs further complicates the decision making. NSCC attempts to identify mistreatment-free object placement to incur implicit cooperation even among these selfishly behaving domains, and to further identify Nash equilibrium object placement from mistreatment-free object placements so that no domain can unilaterally change its placement and benefit while the others keep theirs unchanged, and to improve the cooperation performance with respect to fairness So far, using a game-theoretic approach NSCC seeks a global object placement in which the individual node access costs are reduced as compared to that when they operate in isolation and achieves Nash equilibrium. Our preliminary experiments with IBR verified its effectiveness. And we discuss the specific issues of NSCC's implementation in NDN.
【Keywords】: Peer-to-peer computing; Games; Cooperative caching; Object recognition; Nash equilibrium; Internet; Silicon
【Paper Link】 【Pages】:1-6
【Authors】: Eduard Grigorescu ; Chamil Kulatunga ; Gorry Fairhurst
【Abstract】: For many years Internet routers have been designed and benchmarked in ways that encourage the use of large buffers. When these buffers accumulate a large standing queue, this can lead to high network path latency. Two AQM algorithms: PIE and CoDel, have been recently proposed to reduce buffer latency by avoiding the drawbacks of previous AQM algorithms like RED. This paper explores the performance of these new algorithms in simulated rural broadband networks where capacity is limited. We compared the new algorithms using Adaptive RED as a reference. We observe that to achieve a small queuing delay PIE and CoDel both increase packet loss. We therefore explored this impact on the quality of experience for loss-sensitive unreliable multimedia applications, such as real-time and near-real-time video. The results from simulations show that PIE performs better than CoDel in terms of packet loss rates affecting video quality. We also noted that the performance of ARED is comparable to that of PIE and CoDel in constant capacity links. This suggests that AQM in general is useful for limited capacity network paths.
【Keywords】: QoE; Active Queue Management; Adaptive RED; PIE; CoDel; Real-time Voice; VoIP; Rural Broadband
【Paper Link】 【Pages】:1-6
【Authors】: Piers O'Hanlon ; Ken Carlberg
【Abstract】: This paper provides an overview of the DFlow congestion control algorithm, which aims to provide for lower delay and lower loss media transport. We provide an evaluation of the algorithm in a simulator which shows that it can provide for self-fairness and low delay operation. Furthermore we demonstrate that it can maintain reasonable throughput against TCP Vegas and LEDBAT.
【Keywords】: Equations; Receivers
【Paper Link】 【Pages】:1-6
【Authors】: Nuruddeen Iya ; Fabio Verdicchio ; Gorry Fairhurst
【Abstract】: Real-time media applications often ignore ongoing congestion if there is no option to reduce the rate. These applications pose a threat to themselves and other traffic. Reducing the transmission rate requires reducing the amount of packets rather than spreading the transmission over a longer interval. Loss-based congestion control mechanisms are unsuitable for this requirement. Also this rate reduction with popular video codecs, e.g. MPEG4, is often problematic. This paper investigates the problems associated with real-time video transmission over the Internet. We investigate a rate control method minimizing delay and losses and report preliminary but promising results.
【Keywords】: Streaming media; Delays; Receivers; Loss measurement; Visualization; Switches; Media
【Paper Link】 【Pages】:1-6
【Authors】: Henna Suomi ; Arturo Basaure ; Heikki Hämmäinen
【Abstract】: The growth of mobile Internet usage is raising concerns about the sufficiency of capacity in networks. Therefore, several technical solutions are currently being developed and standardized to increase the efficiency in the radio access and on the entire end-to-end Internet path. If successfully deployed, these technologies will have a significant impact on the Internet connectivity market, especially the mobile access competition. The objective of this paper is to shed light on the different evolution paths of the mobile access market which developments in technical, economic and regulatory domains could induce in the future. This paper envisions operator and end-user centric competition scenarios and compares them against the current vertical competition between mobile network operators (MNOs). The analysis shows that the degree of competition in the mobile access in the future is highly dependent on the level of transaction and switching costs. The end user scenario with related multipath protocol deployments intensifies the competition more than the operator scenario enabled by software-based dynamic spectrum management.
【Keywords】: switching costs; competition; dynamic spectrum management; multipath protocols; transaction costs
【Paper Link】 【Pages】:1-6
【Authors】: Daniel Philip Venmani ; Yvon Gourhant ; Djamal Zeghlache
【Abstract】: Competitive Mobile Network Operators (MNOs) are typically long-known for their shrewdness to conceal their underlying network topology information. Having said this, in this article, we propose a quasi-distributed topology information sharing framework for network operators based on logically centralized controllers. Through our approach, we present a topology information sharing scheme in which two or more MNOs can cooperatively and more importantly, discreetly reveal their topology information for the sake of utilizing the unused available resources of each other, at times of network failure situations. Our approach has been formulated and developed based on a novel key metric to `tune' the amount of information sharing. Based on extensive simulations, we then investigate the impacts of network topology information sharing on the network capacity. The overall feasibility is illustrated through significant numerical results.
【Keywords】: Optimization; Mobile Backhaul Networks; Distributed Topology Information; Logically Centralized Controllers
【Paper Link】 【Pages】:1-6
【Authors】: Konstantinos Samdanis ; Faisal Ghias Mir ; Dirk Kutscher ; Tarik Taleb
【Abstract】: This paper introduces the concept of dynamic Service Boost and proposes deployment solutions in mobile networks focusing on the 3GPP Long Term Evolution (LTE) architecture. The main idea is to introduce a time bound preferential service to subscribers based on predefined service contracts. By applying a light-weight, dynamic Quality of Service (QoS) control, operators achieve both, efficient network utilization and adequate QoS for users and content/application providers. This helps operators to use resources more efficiently, for example to enable a more efficient capacity sharing in the presence of increasing mobile traffic. We initially investigate the impact of Service Boost on Over-The-Top (OTT) traffic transmitted without any specific QoS guarantees over the so-called default bearer in LTE. Then we consider the design and analysis of a Service Boost architecture and framework for managing and prioritizing service requirements for certain applications within LTE. Finally, we elaborate the realization of Service Boost through congestion accountability.
【Keywords】: Quality of service; Servers; Mobile communication; Mobile computing; Computer architecture; Long Term Evolution; Limiting
【Paper Link】 【Pages】:1-6
【Authors】: Mateus A. S. Santos ; Bruno Trevizan de Oliveira ; Cintia B. Margi ; Bruno Astuto A. Nunes ; Thierry Turletti ; Katia Obraczka
【Abstract】: This paper proposes a novel approach to capacity sharing in hybrid networked environments, i.e., environments that consist of infrastructure-based as well as infrastructureless networks. The proposed framework is based on Software-Defined Networking (SDN) and provides flexible, efficient, and secure capacity sharing solutions in a variety of hybrid network scenarios. In this paper, we describe the challenges raised by capacity sharing in hybrid networks, describe our framework in detail and how it addresses these challenges, and discuss implementation issues. To the best of our knowledge, this is the first SDN-based capacity sharing solution that targets hybrid networks and that incorporates security as an integral part of the proposed approach.
【Keywords】: Logic gates; Authentication; Public key; Encryption; Internet
【Paper Link】 【Pages】:1-6
【Authors】: Anduo Wang ; Salar Moarref ; Boon Thau Loo ; Ufuk Topcu ; Andre Scedrov
【Abstract】: With the tremendous growth of the Internet and the emerging software-defined networks, there is an increasing need for rigorous and scalable network management methods and tool support. This paper proposes a synthesis approach for managing software-defined networks. We formulate the construction of network control logic as a reactive synthesis problem which is solvable with existing synthesis tools. The key idea is to synthesize a strategy that manages control logic in response to network changes while satisfying some network-wide specification. Finally, we investigate network abstractions for scalability. For large networks, instead of synthesizing control logic directly, we use its abstraction-a smaller network that simulates its behavior-for synthesis, and then implement the synthesized control on the original network while preserving the correctness. By using the so-called simulation relations, we also prove the soundness of this abstraction-based synthesis approach.
【Keywords】: Abstracts; Switches; Games; Access control; Routing; Gold
【Paper Link】 【Pages】:1-6
【Authors】: C. Jasson Casey ; Andrew Sutton ; Gabriel Dos Reis ; Alex Sprintson
【Abstract】: Incorrect implementations of network protocol message specifications affect the stability, security, and cost of network system development. Most implementation defects fall into one of three categories of well defined message constraints. However, the general process of constructing network protocol stacks and systems does not capture these categorical constraints. We introduce a systems programming language with new abstractions that capture these constraints. Safe and efficient implementations of standard message handling operations are synthesized by our compiler, and whole-program analysis is used to ensure constraints are never violated. We present language examples using the OpenFlow protocol.
【Keywords】: Protocols; Semantics; Payloads; Vectors; Arrays; Computer languages; Program processors
【Paper Link】 【Pages】:1-6
【Authors】: Pedro Amaral ; Luis Bernardo ; Paulo Pinto
【Abstract】: Algebra has made the tasks of defining routing algorithms and proving their correct operation very clear. However, current results in the modelling of multipath policy routing protocols only prove correct behaviour for models that exhibit a strict decrease in the preference of a path with every added link. This is very rigid for multipath routing. For instance it does not allow a link attribute to dominate the entire path classification or having equivalent paths with similar policy but a different number of links. This paper starts by defining the fundamental sufficient conditions for the correct operation of a multipath policy routing protocol with independent destination based hop-by-hop forwarding. We then study the sufficient properties that the protocol model should exhibit so that those conditions are met. We prove that correct operation is possible without the strict increase in preference, provided that the policies applied to links forming circuits in the network graph are restricted. We derive two conditions on the policies applied in the circuits of a network graph that assure correct behaviour and can serve as a tool in the design process.
【Keywords】: policy routing; multipath routing; algebraic routing models
【Paper Link】 【Pages】:1-6
【Authors】: Peter Peresíni ; Dejan Kostic
【Abstract】: Ensuring correct network behavior is hard. Previous state of the art has demonstrated that analyzing a network containing middleboxes is hard. In this paper, we show that even using only statically configured switches, and asking the simplest possible question - “Will this concrete packet reach the destination?” - can make the problem intractable. Moreover, we demonstrate that this is a fundamental property because a network can perform arbitrary computations. Namely, we show how to emulate the Rule 110 cellular automaton using only basic network switches with simple features such as packet matching, header rewriting and round-robin loadbalancing. This ultimately means that analyzing dynamic network behavior can be as hard as analyzing an arbitrary program.
【Keywords】: Logic gates; Ports (Computers); Wires; Turing machines; Computational modeling; Polynomials
【Paper Link】 【Pages】:1-6
【Authors】: Rowan Klöti ; Vasileios Kotronis ; Paul Smith
【Abstract】: Software Defined Networking (SDN) has been proposed as a drastic shift in the networking paradigm, by decoupling network control from the data plane and making the switching infrastructure truly programmable. The key enabler of SDN, OpenFlow, has seen widespread deployment on production networks and its adoption is constantly increasing. Although openness and programmability are primary features of OpenFlow, security is of core importance for real-world deployment. In this work, we perform a security analysis of OpenFlow using STRIDE and attack tree modeling methods, and we evaluate our approach on an emulated network testbed. The evaluation assumes an attacker model with access to the network data plane. Finally, we propose appropriate counter-measures that can potentially mitigate the security issues associated with OpenFlow networks. Our analysis and evaluation approach are not exhaustive, but are intended to be adaptable and extensible to new versions and deployment contexts of OpenFlow.
【Keywords】: Switches; Computer crime; Protocols; Delays; Context
【Paper Link】 【Pages】:1-6
【Authors】: Victor Perez ; Mevlut Turker Garip ; Silas Lam ; Lixia Zhang
【Abstract】: Security is an integral part of networked computer systems. The recent Named Data Networking (NDN) project aims to develop a new Internet architecture that communicates data using names rather than locations, the latter of which is what the current IP-based Internet does with IP addresses. One of the first real-world applications using NDN is a lighting control system. We conduct a red team assessment of the current state of the security of this lighting system and its NDN implementation. The system is representative of a more general class of automated controller systems. Our analysis found that due to NDN's use of named data, the system inherently prevents most attacks that IP-based systems are vulnerable to. Although many parts of the system are secure, we discovered some problems with the verification of timestamps and processing of large packets that led to a severe memory leak. The system also lacks a secure key distribution mechanism. While NDN security is on the right track, there are important security design issues NDN must account for.
【Keywords】: Building automation; Computer networks; Computer security
【Paper Link】 【Pages】:1-6
【Authors】: Daniel Posch ; Hermann Hellwagner ; Peter Schartner
【Abstract】: This paper proposes a framework for on-demand video streaming that enables secure and efficient delivery of data towards the end user. Our proposal requires the combined usage of three different technologies. The first one is a recent proposal by Jacobsen et al. [1][2] called Content-Centric Networking (also known as Named Data Networking). It is a network architecture that introduces named data as the most valuable element in the network and divides it into so called content chunks, which are self-identifying and self-authenticating data units. The second concept we utilize derives from the approach of Dynamic Adaptive Streaming over HTTP [3], which allows clients to dynamically choose the quality of the received video stream according to their available resources. Finally, we adapt the concept of Broadcast Encryption [4] to form a tool to control the access to provided content streams. The combination of these technologies enables us to design a framework that allows streaming providers to transport data to customers as dynamic adaptive encrypted content chunks, which is an efficient, flexible and scalable way of multimedia data transport.
【Keywords】: Video on Demand; Content-Centric Networking; Dynamic Adaptive Streaming over HTTP; Broadcast Encryption
【Paper Link】 【Pages】:1-6
【Authors】: Zhe Chen ; Hongbin Luo ; Jianbo Cui ; Mingshuang Jin
【Abstract】: In this paper, we analyze the security threats of a newly proposed future Internet architecture called CoLoR. In particular, we describe how CoLoR defends against the most prevalent attacks existing in both the current Internet and some recently proposed information-centric networks such as named data networking (NDN). We also present attacks that are specific to CoLoR and discuss how to deal with them. Through our analysis, we find that CoLoR is more secure than both the current Internet and NDN.
【Keywords】: Security; Network Architecture; Attacks
【Paper Link】 【Pages】:1-6
【Authors】: Lara Codeca ; Raphael Frank ; Thomas Engel
【Abstract】: Over the last few years vehicular traffic density has continuously increased and it is likely that the traffic demand will further increase in the future. In many metropolitan areas the road infrastructure is no longer able to handle the peak traffic demand and the existing road network cannot be easily extended. The best way to improve the traffic situation is to optimise the resources available in the transportation network and to coordinate the traffic demand. The approach that we propose in this paper makes use of a collaborative traffic coordination protocol which collects real-time Floating Car Data (FCD) directly from participating vehicles and suggests dynamic routes in order to minimize travel delay. Information such as speed, position and direction is sent to one or more Traffic Coordination Points (TCPs) where it is aggregated to obtain a global picture of the traffic conditions in real-time. Based on this data, we continuously compute the route that minimizes the travel time to a given destination by applying Wardrop's first principle of equilibrium. Our results show that, by coordinating the vehicles, we are able to better distribute the overall traffic demand throughout the transportation network, reducing the average travel times and accommodating more vehicles.
【Keywords】: Wardrop Equilibrium; Intelligent Transportation Systems; Urban Traffic; Traffic Flow Optimization
【Paper Link】 【Pages】:1-6
【Authors】: Hamid Menouar ; Fethi Filali ; Adnan Abu-Dayya
【Abstract】: This paper presents an analysis of link asymmetry in 5.9GHz vehicular communication by means of on-road experiments, and using a standard compliant vehicular communication platform. Similar works have been conducted in the last decades, especially by relevant industrial stakeholders, but none or only little information has been disclosed to the public. The link asymmetry may have considerable impact on the performance of the adopted communication protocols, therefore it is highly important to study such a topic and share the outcomes with the researcher community; this is one of the main motivations behind this contribution. The importance of the results is twofold: first we show that the antenna position on the car roof has a considerable impact on the communication link, and second we demonstrate that the link symmetry is not as worst as can be imagined since the experiments show that a link can still have a good symmetry up to 300 meters of distance between two connected vehicles.
【Keywords】: vehicular communication; 5.9GHz; vanet; v2v; link symmetry; link asymmetry; wireless Link
【Paper Link】 【Pages】:1-6
【Authors】: Yu-Ting Yu ; Yuanjie Li ; Xingyu Ma ; Wentao Shang ; M. Y. Sanadidi ; Mario Gerla
【Abstract】: Recently, Information Centric Networking (ICN) has attracted much attention also for mobiles. Unlike host-based communication models, ICN promotes data names as the first-class citizen in the network. However, the current ICN name-based routing requires Interests be routed by name to the nearest replica, implying the Interests are flooded in VANET. This introduces large overhead and consequently degrades wireless network performance. In order to maintain the efficiency of ICN implementation in VANET, we propose an opportunistic geo-inspired content based routing method. Our method utilizes the last encounter information of each node to infer the locations of content holders. With this information, the Interests can be geo-routed instead of being flooded to reduce the congestion level of the entire network. The simulation results show that our proposed method reduces the scope of flooding to less than two hops and improves retrieval rate by 1.42 times over flooding-based methods.
【Keywords】: Routing; VANET; ICN
【Paper Link】 【Pages】:1-6
【Authors】: Irina Tal ; Aida Olaru ; Gabriel-Miro Muntean
【Abstract】: Cycling, as a very attractive green form of transportation, is also one of the most sustainable. Electric bicycles, the most popular electric vehicles, subscribe to this type of transportation, being highly environmentally friendly. They have several advantages when compared to traditional bicycles, but also a weak point in terms of long battery (re)charging duration. Consequently power-saving solutions for electric bicycles are of high research interest. In this context, this paper proposes a novel energy-efficient weather-aware route planner (eWARPE) for electric bicycles. The solution makes use of the weather information in order to recommend the optimal departure time that allows the cyclist to avoid the adverse weather conditions and to maximize the energy savings of the electric bicycle. Note that the departure time is in a user-configurable time interval. The departure time can be recommended for a preferred route introduced by the user or for a route built in eWARPE based on user input. The proposed solution was validated through numerical analysis. Moreover, a survey was conducted in order to assess the impact of the adverse weather conditions on cyclists and to measure how the cyclists will benefit from the proposed solution.
【Keywords】: weather-aware; electric bicycles; energy efficient; route planner
【Paper Link】 【Pages】:1-6
【Authors】: German Castignani ; Raphael Frank ; Thomas Engel
【Abstract】: Profiling driving behavior has become a relevant aspect in fleet management, automotive insurance and eco-driving. Detecting inefficient or aggressive drivers can help reducing fleet degradation, insurance policy cost and fuel consumption. In this paper, we present a Fuzzy-Logic based driver scoring mechanism that uses smartphone sensing data, including accelerometers and GPS. In order to evaluate the proposed mechanism, we have collected traces from a testbed consisting in 20 vehicles equipped with an Android sensing application we have developed to this end. The results show that the proposed sensing variables using smartphones can be merged to provide each driver with a single score.
【Keywords】: Vehicles; Acceleration; Sensors; Global Positioning System; Smart phones; Input variables; Accelerometers