Bo Liu, Yanchuan Cao, Yi Cui, Yansheng Lu, Yuan Xue
{"title":"Locality Analysis of BitTorrent-Like Peer-to-Peer Systems","authors":"Bo Liu, Yanchuan Cao, Yi Cui, Yansheng Lu, Yuan Xue","doi":"10.1109/CCNC.2010.5421708","DOIUrl":"https://doi.org/10.1109/CCNC.2010.5421708","url":null,"abstract":"Peer-to-peer (P2P) traffic is arguably the biggest contributor to today's Internet traffic. So far, very limited effort has been paid to theoretically analyze the effect of bringing locality-awareness into P2P applications. In this paper we analyze three locality-awareness policies for BitTorrent-like system: tracker locality(neighbor selection), choker locality (choking and unchoking) and picker locality (piece picking). Based on an H- sphere model which captures the essential property of Internet topology, we analyze how much network load savinig can be expected for these locality policies, as well as their impact to the downloading efficiency of the system. Through analytical study and simulation, we have the following findings. First, when the system enters the steady state, the locality policies proposed in this paper can achieve the same downloading efficiency as the standard BitTorrent system. Second, these locality pollicies can significantly alleviate the traffic load on the Internet. Finally, we find that there exists no all-around winner. Instead, each policy performs the best under different system configuration parameters, such as number of unchoked peers.","PeriodicalId":172400,"journal":{"name":"2010 7th IEEE Consumer Communications and Networking Conference","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126788695","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":"Integrated Design of Hierarchical QAM Modulation and Retransmission Diversity for Multimedia Wireless Networks","authors":"A. Annamalai, J. Matyjas, M. Medley","doi":"10.1109/CCNC.2010.5421624","DOIUrl":"https://doi.org/10.1109/CCNC.2010.5421624","url":null,"abstract":"The current and future wireless systems need to support a multitude of services with a wide range of data rates and reliability requirements. The limited battery resource at the mobile terminals coupled with the hostile multipath fading channel makes the problem of providing reliable multimedia services challenging. In this article, we develop a novel method to mechanize a prioritized unicast transmission at the physical layer in response to the disparate quality of service requirements for multimedia traffic (imposed by upper layers) and investigate how the unequal bit error protection offered by multiresolution modulation is capitalized at the data link layer to yield a substantial throughput gain and minimize the packet loss probability of the \"more important\" packets in an integrated voice/data and delay-sensitive applications (especially in poor and moderate channel conditiom). However, there exists a slight throughput penalty in the high signal-to-noise ratio regime due to competitive nature of the \"optimal reliable signaling rate\" in an unknown time-varying channel.","PeriodicalId":172400,"journal":{"name":"2010 7th IEEE Consumer Communications and Networking Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129192843","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":"A Network Lifetime Aware Cooperative MAC Scheme for 802.11b Wireless Networks","authors":"Abhik Banerjee, C. Foh, C. Yeo, Bu-Sung Lee","doi":"10.1109/CCNC.2010.5421811","DOIUrl":"https://doi.org/10.1109/CCNC.2010.5421811","url":null,"abstract":"Cooperative communication techniques have earlier been applied to design of the IEEE 802.11 medium access control (MAC) and shown to perform better. High rate stations can help relay packets from low-rate stations resulting in better throughput for the entire network. However, this also involves additional energy costs on the part of the relay which can result in reducing the network lifetime. We propose a cooperative MAC protocol NetCoop with the objective of maximizing the network lifetime and achieving high throughput. Based on this design, we also propose a flexible strategy which allows cooperation to be achieved using more than one relay. We show that this can achieve at least as good throughput as that of single relay cooperation while maintaining a high network lifetime.","PeriodicalId":172400,"journal":{"name":"2010 7th IEEE Consumer Communications and Networking Conference","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124027085","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":"Two-Dimensional Differential Demodulation for 64-DAPSK Modulated OFDM Signals","authors":"Min Gong, Yusheng Ji, Han Han, Xiaokang Lin","doi":"10.1109/CCNC.2010.5421843","DOIUrl":"https://doi.org/10.1109/CCNC.2010.5421843","url":null,"abstract":"A novel two-dimensional differential demodulation (2-D DD) algorithm, which exploits both the time and frequency dimensions by using the orthogonal frequency division multiplexing (OFDM) frame structure, was investigated for 64-differential amplitude and phase shift keying (DAPSK) modulated OFDM signals. Without changing the transmitter, the proposed algorithm based on graph attempts to search for a more confident bypass, probably containing multiple DD operations, to demodulate one 64-DAPSK symbol rather than conventional direct DD. In order to carry out the optimal path searching process, the soft decision metrics of the amplitude ratio and phase difference were derived by making use of a Gaussian approximation. Simulation results show that the proposed algorithm can obtain substantial performance gains with reasonable computational complexity for uncoded AWGN and frequency selective fading channels. In addition, it is advantageous to withstand the Doppler effect, which is hence suitable for high mobile (e.g., in a car or train) broadband wireless access (BWA) systems.","PeriodicalId":172400,"journal":{"name":"2010 7th IEEE Consumer Communications and Networking Conference","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121408463","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":"Advanced Aggregation Techniques for Integrated Next-Generation WLAN and EPON Networks","authors":"N. Ghazisaidi, M. Maier","doi":"10.1109/CCNC.2010.5421851","DOIUrl":"https://doi.org/10.1109/CCNC.2010.5421851","url":null,"abstract":"In this paper, we focus on the MAC enhancements of emerging high-throughput WLANs and introduce a novel fiber-wireless (FiWi) network architecture that integrates next-generation WLAN and EPON in a pay-as-you-grow manner while providing backward compatibility with legacy infrastructure and protecting previous investments. Our work sheds light onto the benefits of extending advanced frame aggregation techniques from next-generation WLANs to EPONs as well. We examine different path selection schemes to improve FiWi network performance by means of wireless mesh networking, considering not only throughput and delay but also overhead and packet loss.","PeriodicalId":172400,"journal":{"name":"2010 7th IEEE Consumer Communications and Networking Conference","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114562954","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}
T. Wu, K. Kwong, Chong Shen, W. Michie, Ivan Andonovic
{"title":"The Impact of Physical Conditions on Network Connectivity in Wireless Sensor Network","authors":"T. Wu, K. Kwong, Chong Shen, W. Michie, Ivan Andonovic","doi":"10.1109/CCNC.2010.5421687","DOIUrl":"https://doi.org/10.1109/CCNC.2010.5421687","url":null,"abstract":"In Wireless Sensor Networks, end-to-end routing paths need to be established when nodes want to communicate with the desired destination. For nodes assumed to be static, many routing protocols such as Directed Diffusion have been proposed to meet this requirement efficiently. The performance of such routing protocols is relative to the given network connectivity. This paper addresses mobile sensor nodes taking into account the diversity of scattered node density and investigates how physical conditions impact on network connectivity which in turn influences routing performance. Three analysis metrics: path availability, path duration, and interavailable path time are proposed to quantify the impact of different physical conditions on network connectivity. Simulation results show that the network connectivity varies significantly as a function of different physical conditions.","PeriodicalId":172400,"journal":{"name":"2010 7th IEEE Consumer Communications and Networking Conference","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124128369","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":"Distributed Turbo Product Codes over Multiple Relays","authors":"Esam A. Obiedat, G. Chen, Lei Cao","doi":"10.1109/CCNC.2010.5421778","DOIUrl":"https://doi.org/10.1109/CCNC.2010.5421778","url":null,"abstract":"In this paper, we propose a Distributed Turbo Product Code (DTPC) over cooperative network using block Bose Chaudhuri Hochquenghem (BCH) codes as component codes. The source broadcasts extended BCH coded frames to the destination and nearby relays. After decoding the received sequences, each relay constructs a product code by arranging the corrected bit sequences in rows and re-encoding them vertically using BCH as component codes to obtain an Incremental Redundancy (IR) for source's data. To obtain independent vertical parities from each relay in the same code space, different circular interleavers are proposed to interleave BCH rows before reencoding vertically. A modified turbo product decoder to cope with Multiple Vertical Parities (MVP) is used at the destination to iteratively decode the systematic data from the source and the vertical parities generated by the relays. Simulation results in Additive White Gaussian Noise (AWGN) channel using network scenarios show 0.3-0.5dB gain improvement in Bit Error Rate (BER) performance over the non-cooperative Turbo Product Codes (TPC).","PeriodicalId":172400,"journal":{"name":"2010 7th IEEE Consumer Communications and Networking Conference","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127767486","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":"Distributed Amplify-and-Forward with Ring-TCM Codes","authors":"Li Chen, R. Carrasco, I. Wassell","doi":"10.1109/CCNC.2010.5421691","DOIUrl":"https://doi.org/10.1109/CCNC.2010.5421691","url":null,"abstract":"This paper proposes a new distributed Amplify-and-Forward (AF) scheme which is integrated with the Ring-Trellis Coded Modulation (TCM) codes in order to achieve both high spectral efficiency and large diversity gain. In the distributed AF scheme, more users cooperate with each other. Each user still uses half of its transmission freedom for relaying others' signal. However, different to the conventional AF scheme, each user further partitions its relay transmission into smaller divisions in order to help more users. As a result, for each user, the distributed AF scheme will have the same spectral efficiency as the conventional AF scheme, but creating more diverse transition paths and providing better diversity gain. In the scheme, output symbols are demultiplexed into several subframes, each of which will be relayed by a different user. As a result, each output symbol from a trellis transition branch can be relayed by a different user, assisting error-correction performance of the decoder. This distributed coding scheme is suitable for different wireless access systems, such as WiLAN and WiMAX systems. Our simulation results show that with the same spectral efficiency, the distributed coded AF scheme can significantly outperform the conventional coded AF scheme.","PeriodicalId":172400,"journal":{"name":"2010 7th IEEE Consumer Communications and Networking Conference","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126289248","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":"MCCA: Multihop Clear Channel Assessment In 802.11 DCF","authors":"G. Learmonth, JoAnne Holliday","doi":"10.1109/CCNC.2010.5421699","DOIUrl":"https://doi.org/10.1109/CCNC.2010.5421699","url":null,"abstract":"We present a discussion and study of the RTS/CTS channel clearing mechanism used in the 802.11 DCF and propose a possible improvement. We focus on why the current mechanism is only a single hop process, what disadvantages this presents and what advantages a multihop version of RTS/CTS would bring. We describe why the proposed multihop approach, called Multihop Clear Channel Assessment (MCCA), brings various improvements and how it can be used in isolation in ad hoc or infrastructure mode networks and with or without additional layer 2 (L2) or layer 3 (L3) routing protocols present, depending on the purpose and performance goals of the network. MCCA should not be construed as a L2 ad hoc routing protocol but an enhanced version of RTS/CTS. MCCA is well suited to wireless home networks where it has been shown [1] that even in modest residences, full wireless connectivity is not guaranteed and using additional routing protocols at L2 or L3 may add latency and reduce throughput which could jeopardize the high bandwidth, rich media applications typical of the home network environment. We therefore ask and attempt to answer the question, what can we do to improve 802.11 based wireless networks at the fundamental MAC layer with respect to ensuring as close to full connectivity as possible before resorting to L2 or L3 routing?.","PeriodicalId":172400,"journal":{"name":"2010 7th IEEE Consumer Communications and Networking Conference","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126493147","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}
K. Kotani, Weihua Sun, T. Kitani, N. Shibata, K. Yasumoto, Minoru Ito
{"title":"Inter-Vehicle Communication Protocol for Cooperatively Capturing and Sharing Intersection Video","authors":"K. Kotani, Weihua Sun, T. Kitani, N. Shibata, K. Yasumoto, Minoru Ito","doi":"10.1109/CCNC.2010.5421635","DOIUrl":"https://doi.org/10.1109/CCNC.2010.5421635","url":null,"abstract":"For accident prevention at intersections, it is useful for drivers to grasp the position of vehicles in blind spots. This can be achieved without infrastructure if some vehicles passing near the intersection capture and share live video of the intersection through inter-vehicle communications. However, such video streaming requires a congestion control mechanism. In this paper, aiming to let a driver grasp the situation at an intersection, we propose a method to select vehicles that send a video in order to generate a live bird's-eye-view video of the intersection. In our method, each vehicle at an intersection exchanges information with others, such as the sub-areas of the intersection it captures, the quality of its video, and its position and speed. Based on the exchanged information, each vehicle autonomously judges whether it should send its video or not. Through simulation with a QualNet simulator, we confirm that our method achieves a good video arrival rate and video quality sufficient for practical use.","PeriodicalId":172400,"journal":{"name":"2010 7th IEEE Consumer Communications and Networking Conference","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134252790","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}