{"title":"Stable Peers: Existence, Importance, and Application in Peer-to-Peer Live Video Streaming","authors":"Feng Wang, Jiangchuan Liu, Y. Xiong","doi":"10.1109/INFOCOM.2008.194","DOIUrl":"https://doi.org/10.1109/INFOCOM.2008.194","url":null,"abstract":"This paper presents a systematic in-depth study on the existence, importance, and application of stable nodes in peer- to-peer live video streaming. Using traces from a real large-scale system as well as analytical models, we show that, while the number of stable nodes is small throughout a whole session, their longer lifespans make them constitute a significant portion in a per-snapshot view of a peer-to-peer overlay. As a result, they have substantially affected the performance of the overall system. Inspired by this, we propose a tiered overlay design, with stable nodes being organized into a tier-1 backbone for serving tier-2 nodes. It offers a highly cost-effective and deployable alternative to proxy-assisted designs. We develop a comprehensive set of algorithms for stable node identification and organization. Specifically, we present a novel structure, Labeled Tree, for the tier-1 overlay, which, leveraging stable peers, simultaneously achieves low overhead and high transmission reliability. Our tiered framework flexibly accommodates diverse existing overlay structures in the second tier. Our extensive simulation results demonstrated that the customized optimization using selected stable nodes boosts the streaming quality and also effectively reduces the control overhead. This is further validated through prototype experiments over the PlanetLab network.","PeriodicalId":447520,"journal":{"name":"IEEE INFOCOM 2008 - The 27th Conference on Computer Communications","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116627568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Gang Zhou, Jian Lu, Chieh-Yih Wan, M. Yarvis, J. Stankovic
{"title":"BodyQoS: Adaptive and Radio-Agnostic QoS for Body Sensor Networks","authors":"Gang Zhou, Jian Lu, Chieh-Yih Wan, M. Yarvis, J. Stankovic","doi":"10.1109/INFOCOM.2008.105","DOIUrl":"https://doi.org/10.1109/INFOCOM.2008.105","url":null,"abstract":"As wireless devices and sensors are increasingly deployed on people, researchers have begun to focus on wireless body-area networks. Applications of wireless body sensor networks include healthcare, entertainment, and personal assistance, in which sensors collect physiological and activity data from people and their environments. In these body sensor networks, quality of service is needed to provide reliable data communication over prioritized data streams. This paper proposes BodyQoS, the first running QoS system demonstrated on an emulated body sensor network. BodyQoS adopts an asymmetric architecture, in which most processing is done on a resource rich aggregator, minimizing the load on resource limited sensor nodes. A virtual MAC is developed in BodyQoS to make it radio-agnostic, allowing a BodyQoS to schedule wireless resources without knowing the implementation details of the underlying MAC protocols. Another unique property of BodyQoS is its ability to provide adaptive resource scheduling. When the effective bandwidth of the channel degrades due to RF interference or body fading effect, BodyQoS adaptively schedules remaining bandwidth to meet QoS requirements. We have implemented BodyQoS in NesC on top of TinyOS, and evaluated its performance on MicaZ devices. Our system performance study shows that BodyQoS delivers significantly improved performance over conventional solutions in combating channel impairment.","PeriodicalId":447520,"journal":{"name":"IEEE INFOCOM 2008 - The 27th Conference on Computer Communications","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116756672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Delay Analysis for Maximal Scheduling in Wireless Networks with Bursty Traffic","authors":"M. Neely","doi":"10.1109/INFOCOM.2008.10","DOIUrl":"https://doi.org/10.1109/INFOCOM.2008.10","url":null,"abstract":"We consider the delay properties of one-hop networks with general interference constraints and multiple traffic streams with time-correlated arrivals. We first treat the case when arrivals are modulated by independent finite state Markov chains. We show that the well known maximal scheduling algorithm achieves average delay that grows at most logarithmically in the largest number of interferers at any link. Further, in the important special case when each Markov process has at most two states (such as bursty ON/OFF sources), we prove that average delay is independent of the number of nodes and links in the network, and hence is order-optimal. We provide tight delay bounds in terms of the individual auto-correlation parameters of the traffic sources. These are perhaps the first order-optimal delay results for controlled queueing networks that explicitly account for such statistical information.","PeriodicalId":447520,"journal":{"name":"IEEE INFOCOM 2008 - The 27th Conference on Computer Communications","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116994254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Designing a Fault-Tolerant Network Using Valiant Load-Balancing","authors":"Rui Zhang-Shen, N. McKeown","doi":"10.1109/INFOCOM.2008.305","DOIUrl":"https://doi.org/10.1109/INFOCOM.2008.305","url":null,"abstract":"Commercial backbone networks must continue to operate even when links and routers fail. Routing schemes such as OSPF, IS-IS, and MPLS reroute traffic, but they cannot guarantee that the resulting network will be congestion-free. As a result, backbone networks are grossly over-provisioned - sometimes running at a utilization below 10% so they can remain uncongested under failure. Yet even with such large over-provisioning, they still cannot guarantee to be uncongested, sometimes even with just a single failure. With our proposed approach, a network can be designed to tolerate an almost arbitrary number of failures, and guarantee no congestion, usually with an extremely small amount of over- provisioning. In a typical case, a 50 node network can continue to run congestion-free when any 5 links or routers fail, with only 10% over-provisioning. The key to the approach is Valiant Load-Balancing (VLB). VLB's path diversity allows it to tolerate k arbitrary failures in an N node network, with over-provisioning ratio of approximately k/N.","PeriodicalId":447520,"journal":{"name":"IEEE INFOCOM 2008 - The 27th Conference on Computer Communications","volume":"199 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116402759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Multihop Local Pooling for Distributed Throughput Maximization in Wireless Networks","authors":"G. Zussman, A. Brzezinski, E. Modiano","doi":"10.1109/INFOCOM.2008.169","DOIUrl":"https://doi.org/10.1109/INFOCOM.2008.169","url":null,"abstract":"Efficient operation of wireless networks requires distributed routing and scheduling algorithms that take into account interference constraints. Recently, a few algorithms for networks with primary- or secondary-interference constraints have been developed. Due to their distributed operation, these algorithms can achieve only a guaranteed fraction of the maximum possible throughput. It was also recently shown that if a set of conditions (known as Local Pooling) is satisfied, simple distributed scheduling algorithms achieve 100% throughput. However, previous work regarding Local Pooling focused mostly on obtaining abstract conditions and on networks with single-hop interference or single-hop traffic. In this paper, we identify several graph classes that satisfy the Local Pooling conditions, thereby enabling the use of such graphs in network design algorithms. Then, we study the multihop implications of Local Pooling. We show that in many cases, as the interference degree increases, the Local Pooling conditions are more likely to hold. Consequently, although increased interference reduces the maximum achievable throughput of the network, it tends to enable distributed algorithms to achieve 100% of this throughput. Regarding multihop traffic, we show that if the network satisfies only the single-hop Local Pooling conditions, distributed joint routing and scheduling algorithms are not guaranteed to achieve maximum throughput. Therefore, we present new conditions for Multihop Local Pooling, under which distributed algorithms achieve 100% throughout. Finally, we identify network topologies in which the conditions hold and discuss the algorithmic implications of the results.","PeriodicalId":447520,"journal":{"name":"IEEE INFOCOM 2008 - The 27th Conference on Computer Communications","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115234017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Exploiting Multi-Channel Diversity in Spectrum-Agile Networks","authors":"Alexander W. Min, K. Shin","doi":"10.1109/INFOCOM.2008.256","DOIUrl":"https://doi.org/10.1109/INFOCOM.2008.256","url":null,"abstract":"Recently, spectrum-agile (SA) networks have been recognized as a viable solution to the spectrum-scarcity problem in spectrum-scarcity problem. In SA networks, secondary (unlicensed) users are allowed to opportunistically utilize idle licensed spectrum bands, thus improving spectrum utilization efficiency and accommodating more users and applications. We take a two- step approach to the problem of maximizing the throughput of an SA network. The first step is to determine a subset of \"candidate\" channels that a secondary device will consider for its channel-switching. The candidate channels are selected based on their estimated utilization. We then propose channel-aware switching to determine when and where to switch to, among the candidate channels. Wireless channels are assumed to experience independent Rayleigh fading, and modeled with a finite-state Markov channel (FSMC) model. Our evaluation results show that the proposed channel-aware switching scheme significantly outperforms the traditional forced-switching scheme in terms of average throughput.","PeriodicalId":447520,"journal":{"name":"IEEE INFOCOM 2008 - The 27th Conference on Computer Communications","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115322150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Index Policies for Real-Time Multicast Scheduling for Wireless Broadcast Systems","authors":"V. Raghunathan, V. Borkar, M. Cao, P. Kumar","doi":"10.1109/INFOCOM.2008.217","DOIUrl":"https://doi.org/10.1109/INFOCOM.2008.217","url":null,"abstract":"Motivated by the increasing usage of wireless broadcast networks for multicast real-time applications like video, this paper considers a canonical real-time multicast scheduling problem for a wireless broadcast LAN. A wireless access point (AP) has N latency-sensitive flows, each associated with a deadline and a multicast group of receivers that desire to receive all the packets successfully by their corresponding deadlines. We consider periodic and one-shot models of real-time arrivals. The channel from the AP to each receiver is a wireless erasure channel, independent across users and slots. We wish to find a communication strategy that minimizes the total deadlines missed across all receivers, where a receiver counts a miss if it does not receive a packet by its deadline. We cast this problem as a restless bandit in stochastic control. We use Whittle's relaxation framework for restless bandits to establish Whittle-indexability for multicast realtime scheduling under the assumption of complete feedback from all receivers in every slot. For the Whittle relaxation, we show that for each flow, the AP's decision between transmitting in a slot and idling has a threshold structure. For the homogeneous case where the erasure channel to each receiver is identically distributed with parameter p, the Whittle index of a flow is xi(1 - p) , where xi is the number of receivers who have yet to receive the current packet of flow i. For the general heterogeneous case in which the erasure channel to receiver j has loss probability pj, the Whittle index corresponding to each flow is Sigmaj (1- pj), where the sum is over all multicast receivers who are yet to receive the packet. We bound the performance of the optimal Whittle relaxation with respect to the optimal wireless multicast real-time scheduler. The heuristic index policy that schedules the flow with the maximum Whittle index in each slot is simple. To relax the complete feedback assumption, we design a scalable mechanism based on statistical estimation theory that obtains the required feedback from all the receivers using a single ACK per packet transmission. The resultant policy is amenable to low-complexity implementation.","PeriodicalId":447520,"journal":{"name":"IEEE INFOCOM 2008 - The 27th Conference on Computer Communications","volume":"119 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114592819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Beyond TCAMs: An SRAM-Based Parallel Multi-Pipeline Architecture for Terabit IP Lookup","authors":"Weirong Jiang, Qingbo Wang, V. Prasanna","doi":"10.1109/INFOCOM.2008.241","DOIUrl":"https://doi.org/10.1109/INFOCOM.2008.241","url":null,"abstract":"Continuous growth in network link rates poses a strong demand on high speed IP lookup engines. While Ternary Content Addressable Memory (TCAM) based solutions serve most of today's high-end routers, they do not scale well for the next-generation. On the other hand, pipelined SRAM- based algorithmic solutions become attractive. Intuitively multiple pipelines can be utilized in parallel to have a multiplicative effect on the throughput. However, several challenges must be addressed for such solutions to realize high throughput. First, the memory distribution across different stages of each pipeline as well as across different pipelines must be balanced. Second, the traffic on various pipelines should be balanced. In this paper, we propose a parallel SRAM-based multi- pipeline architecture for terabit IP lookup. To balance the memory requirement over the stages, a two-level mapping scheme is presented. By trie partitioning and subtrie-to-pipeline mapping, we ensure that each pipeline contains approximately equal number of trie nodes. Then, within each pipeline, a fine-grained node-to-stage mapping is used to achieve evenly distributed memory across the stages. To balance the traffic on different pipelines, both pipelined prefix caching and dynamic subtrie-to-pipeline remapping are employed. Simulation using real-life data shows that the proposed architecture with 8 pipelines can store a core routing table with over 200 K unique routing prefixes using 3.5 MB of memory. It achieves a throughput of up to 3.2 billion packets per second, i.e. 1 Tbps for minimum size (40 bytes) packets.","PeriodicalId":447520,"journal":{"name":"IEEE INFOCOM 2008 - The 27th Conference on Computer Communications","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123663878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Reliability Gain of Network Coding in Lossy Wireless Networks","authors":"Majid Ghaderi, D. Towsley, J. Kurose","doi":"10.1109/INFOCOM.2008.284","DOIUrl":"https://doi.org/10.1109/INFOCOM.2008.284","url":null,"abstract":"The capacity gain of network coding has been extensively studied in wired and wireless networks. Recently, it has been shown that network coding improves network reliability by reducing the number of packet retransmissions in lossy networks. However, the extent of the reliability benefit of network coding is not known. This paper quantifies the reliability gain of network coding for reliable multicasting in wireless networks, where network coding is most promising. We define the expected number of transmissions per packet as the performance metric for reliability and derive analytical expressions characterizing the performance of network coding. We also analyze the performance of reliability mechanisms based on rateless codes and automatic repeat request (ARQ), and compare them with network coding. We first study network coding performance in an access point model, where an access point broadcasts packets to a group of K receivers over lossy wireless channels. We show that the expected number of transmissions using ARQ, compared to network coding, scales as ominus (log K) as the number of receivers becomes large. We then use the access point model as a building block to study reliable multicast in a tree topology. In addition to scaling results, we derive expressions for the expected number of transmissions for finite multicast groups as well. Our results show that network coding significantly reduces the number of retransmissions in lossy networks compared to an ARQ scheme. However, rateless coding achieves asymptotic performance results similar to that of network coding.","PeriodicalId":447520,"journal":{"name":"IEEE INFOCOM 2008 - The 27th Conference on Computer Communications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124013497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Dynamic Jamming Mitigation for Wireless Broadcast Networks","authors":"Jerry T. Chiang, Yih-Chun Hu","doi":"10.1109/INFOCOM.2008.177","DOIUrl":"https://doi.org/10.1109/INFOCOM.2008.177","url":null,"abstract":"Wireless communications are inherently symmetric; that is, it takes an attacker the same amount of power to modulate a signal as it does for a legitimate node to modulate the same signal. As a result, wireless communications are often susceptible to the jamming attack in which the attacker injects a high level of noise into the system. Spread spectrum has long been used to resist jamming attacks in unicast environments, or when the jammer has less information than the other receivers. Recently, we proposed a scheme for broadcast jamming mitigation based on spread spectrum and a binary key tree and showed some improvements over a multiple-unicast system. In this paper, we extend our previous work in five ways. First, we provide a theoretical result that under our scheme, jammers can cause only a limited number of losses. Second, we develop a dynamic tree-remerging scheme that achieves higher power efficiency than previously proposed schemes, and scales to an arbitrary number of receivers without increasing the number of codes in use; in particular, we send each transmission on at most 2j + 1 codes, where j is the number of jammers. Third, we show that our scheme is close to optimal, demonstrating that under certain realistic restrictions, the system cannot escape jamming without using at least j +1 codes. Fourth, we provide a detailed analysis of false alarm rates, showing both experimental and theoretical results. Finally, we perform a more extensive analysis of our system using both a chip-accurate MATLAB simulation and a bit-accurate event-driven simulation in the ns-2 network simulator; these simulations demonstrate that our scheme approaches the best possible performance.","PeriodicalId":447520,"journal":{"name":"IEEE INFOCOM 2008 - The 27th Conference on Computer Communications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122383071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}