Pub Date : 2010-07-01DOI: 10.1109/ICC.2010.5502274
F. Chiti, R. Fantacci, D. Vukobratović
In this paper, an approach minimizing delivery latency, while keeping transmitted power below a certain threshold, is proposed to provide reliable real time wireless communications when applying network coding principle in order to point out additional advantage in terms of capacity. An analytical tool is proposed to derive the performance of optimal power adaptation scheme NC scheme aiming at minimizing the number of coded packets transmitted on a link-by-link basis, thereby lowering the end-to-end delay and overall power consumption.
{"title":"Joint Discrete Power-Level and Delay Optimization for Network Coded Wireless Communications","authors":"F. Chiti, R. Fantacci, D. Vukobratović","doi":"10.1109/ICC.2010.5502274","DOIUrl":"https://doi.org/10.1109/ICC.2010.5502274","url":null,"abstract":"In this paper, an approach minimizing delivery latency, while keeping transmitted power below a certain threshold, is proposed to provide reliable real time wireless communications when applying network coding principle in order to point out additional advantage in terms of capacity. An analytical tool is proposed to derive the performance of optimal power adaptation scheme NC scheme aiming at minimizing the number of coded packets transmitted on a link-by-link basis, thereby lowering the end-to-end delay and overall power consumption.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"103 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2010-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78420727","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}
Pub Date : 2010-07-01DOI: 10.1109/ICC.2010.5502007
S. Han, Ye Xia
In this paper, we investigate the issue of server selection for P2P IPTV system on fiber to the node networks. To achieve high performance and resilience to failures, a peer can make connections with multiple peers simultaneously and receive different portions of the data in parallel. Prior work mostly focuses on user-centric performance objectives, such as reducing the round-trip time or the completion time of individual download, but tend to ignore the congestion caused by the concurrent connections or the network load balance. The latter performance concerns are important for the network operators who provide and manage IPTV services. In this paper, we consider two performance metrics, the worst-case link stress (WLS) and the degree of interference (DOI), and present a server selection scheme that generates the optimal server set with respect to the WLS criterion. Through experiments on PlanetLab, we show that the proposed scheme has the advantages over the random scheme and the closest scheme in the following aspects. First, it minimizes the level of congestion at the bottleneck link. Second, it consumes less network resources in terms of the total bandwidth usage. Third, the network load is well balanced.
{"title":"An Optimal Server Selection Algorithm for P2P IPTV over Fiber to the Node (FTTN) Networks","authors":"S. Han, Ye Xia","doi":"10.1109/ICC.2010.5502007","DOIUrl":"https://doi.org/10.1109/ICC.2010.5502007","url":null,"abstract":"In this paper, we investigate the issue of server selection for P2P IPTV system on fiber to the node networks. To achieve high performance and resilience to failures, a peer can make connections with multiple peers simultaneously and receive different portions of the data in parallel. Prior work mostly focuses on user-centric performance objectives, such as reducing the round-trip time or the completion time of individual download, but tend to ignore the congestion caused by the concurrent connections or the network load balance. The latter performance concerns are important for the network operators who provide and manage IPTV services. In this paper, we consider two performance metrics, the worst-case link stress (WLS) and the degree of interference (DOI), and present a server selection scheme that generates the optimal server set with respect to the WLS criterion. Through experiments on PlanetLab, we show that the proposed scheme has the advantages over the random scheme and the closest scheme in the following aspects. First, it minimizes the level of congestion at the bottleneck link. Second, it consumes less network resources in terms of the total bandwidth usage. Third, the network load is well balanced.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"9 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2010-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77901950","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}
Pub Date : 2010-07-01DOI: 10.1109/ICC.2010.5501922
T. Duong, H. Zepernick, T. Tsiftsis, Vo Nguyen Quoc Bao
In this paper, we analyze the performance of dual-hop channel state information (CSI)-assisted amplify-and-forward (AF) cooperative networks using orthogonal space-time block codes (OSTBCs) over independent but not identically distributed Nakagami-$m$ fading channels. Specifically, we present closed-form expressions of the outage probability (OP) and the symbol error probability (SEP). The analytical results are given in tractable forms which readily allow us to assess the performance of AF relay systems using OSTBCs. For sufficiently large signal-to-noise ratio, we obtain the asymptotic results for OP and SEP which reveal insights into the effect of fading factors on the diversity and coding gains. It has been shown that between the two hops the more severe link solely determines the diversity and coding gains. In particular, these two gains strictly depend on the fading severity parameters and the channel mean powers of the more rigorous hop, respectively. Numerical results are provided showing an excellent agreement between our analytical results and those of Monte-Carlo simulations for selected scenarios.
{"title":"Amplify-And-Forward MIMO Relaying with OSTBC over Nakagami-m Fading Channels","authors":"T. Duong, H. Zepernick, T. Tsiftsis, Vo Nguyen Quoc Bao","doi":"10.1109/ICC.2010.5501922","DOIUrl":"https://doi.org/10.1109/ICC.2010.5501922","url":null,"abstract":"In this paper, we analyze the performance of dual-hop channel state information (CSI)-assisted amplify-and-forward (AF) cooperative networks using orthogonal space-time block codes (OSTBCs) over independent but not identically distributed Nakagami-$m$ fading channels. Specifically, we present closed-form expressions of the outage probability (OP) and the symbol error probability (SEP). The analytical results are given in tractable forms which readily allow us to assess the performance of AF relay systems using OSTBCs. For sufficiently large signal-to-noise ratio, we obtain the asymptotic results for OP and SEP which reveal insights into the effect of fading factors on the diversity and coding gains. It has been shown that between the two hops the more severe link solely determines the diversity and coding gains. In particular, these two gains strictly depend on the fading severity parameters and the channel mean powers of the more rigorous hop, respectively. Numerical results are provided showing an excellent agreement between our analytical results and those of Monte-Carlo simulations for selected scenarios.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"6 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2010-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81980761","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}
Pub Date : 2010-07-01DOI: 10.1109/ICC.2010.5502424
J. Sarker, H. Mouftah
A random packet destruction Denial of Service (DoS) attacking signals are easy to mount and difficult to detect and prevent. The attacker does not need to pretend a legal user and able to shut down any Slotted ALOHA based wireless Ad Hoc and sensor networks successfully by reducing the throughput and stability. Since current anti-attack measures such as encryption, authentication and authorization cannot prevent these types of attacks, we propose the use of multiple power levels transmission system to mitigate the attacking signals. Through analysis and numerical examples we demonstrate that the multiple power levels transmission system can significantly improve the throughput and stability of Slotted ALOHA under the random packet destruction Denial of Service (DoS) attacking signals. The implementation of the multiple power levels transmission system is easy and can keep the system running, although current anti-attack measures such as encryption, authentication and authorization cannot prevent these types of attacks.
DoS (random packet destruction Denial of Service)攻击信号是一种易于装载且难以检测和防范的攻击信号。攻击者不需要伪装成合法用户，并且可以通过降低吞吐量和稳定性来成功关闭任何基于Slotted ALOHA的无线Ad Hoc和传感器网络。由于目前的防攻击措施，如加密、认证和授权，不能防止这类攻击，我们建议使用多功率级传输系统来减轻攻击信号。通过分析和数值算例表明，在随机分组破坏拒绝服务(DoS)攻击信号下，多功率级传输系统可以显著提高开槽ALOHA的吞吐量和稳定性。虽然现有的加密、认证、授权等防攻击措施无法阻止这类攻击，但多功率级传输系统的实现简单，可以保证系统的正常运行。
{"title":"Throughput and Stability Improvements of Slotted ALOHA Based Wireless Networks under the Random Packet Destruction Dos Attack","authors":"J. Sarker, H. Mouftah","doi":"10.1109/ICC.2010.5502424","DOIUrl":"https://doi.org/10.1109/ICC.2010.5502424","url":null,"abstract":"A random packet destruction Denial of Service (DoS) attacking signals are easy to mount and difficult to detect and prevent. The attacker does not need to pretend a legal user and able to shut down any Slotted ALOHA based wireless Ad Hoc and sensor networks successfully by reducing the throughput and stability. Since current anti-attack measures such as encryption, authentication and authorization cannot prevent these types of attacks, we propose the use of multiple power levels transmission system to mitigate the attacking signals. Through analysis and numerical examples we demonstrate that the multiple power levels transmission system can significantly improve the throughput and stability of Slotted ALOHA under the random packet destruction Denial of Service (DoS) attacking signals. The implementation of the multiple power levels transmission system is easy and can keep the system running, although current anti-attack measures such as encryption, authentication and authorization cannot prevent these types of attacks.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"8 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2010-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79495447","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}
Pub Date : 2010-07-01DOI: 10.1109/ICC.2010.5502036
Shouhong Zhu, Z. Ding, K. Markarian
Time of arrival (TOA) based joint synchronization and localization is a very important research area for wireless ad hoc sensor network applications. In this paper we propose a computationally efficient algorithm. The proposed algorithm is based on the linearized equations from TOA measurements, and applies a weighted least square criterion that leads to a high estimation performance. Performance analysis and simulation studies provided confirm the proposed algorithm of its superior trade-off between estimation performance and computational complexity.
{"title":"TOA Based Joint Synchronization and Localization","authors":"Shouhong Zhu, Z. Ding, K. Markarian","doi":"10.1109/ICC.2010.5502036","DOIUrl":"https://doi.org/10.1109/ICC.2010.5502036","url":null,"abstract":"Time of arrival (TOA) based joint synchronization and localization is a very important research area for wireless ad hoc sensor network applications. In this paper we propose a computationally efficient algorithm. The proposed algorithm is based on the linearized equations from TOA measurements, and applies a weighted least square criterion that leads to a high estimation performance. Performance analysis and simulation studies provided confirm the proposed algorithm of its superior trade-off between estimation performance and computational complexity.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"38 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2010-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80917184","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}
Pub Date : 2010-05-23DOI: 10.1109/ICC.2010.5501747
Tarem Ahmed
This paper considers the problem of predicting the number, length and distribution of IP traffic flows some time into the future, based upon packets collected in the present. Two versions of the Expectation-Maximization (EM) algorithm are used to predict the mean flow length and complete flow distributions for subsequent timesteps. A model is first used to represent the histogram of flows corresponding to any given time interval, and the EM algorithms are then used to estimate the parameters of the model. The proposed algorithms are tested on a large number of commonly-available data traces and both show high prediction accuracy.
{"title":"Flow Vector Prediction Using EM Algorithms","authors":"Tarem Ahmed","doi":"10.1109/ICC.2010.5501747","DOIUrl":"https://doi.org/10.1109/ICC.2010.5501747","url":null,"abstract":"This paper considers the problem of predicting the number, length and distribution of IP traffic flows some time into the future, based upon packets collected in the present. Two versions of the Expectation-Maximization (EM) algorithm are used to predict the mean flow length and complete flow distributions for subsequent timesteps. A model is first used to represent the histogram of flows corresponding to any given time interval, and the EM algorithms are then used to estimate the parameters of the model. The proposed algorithms are tested on a large number of commonly-available data traces and both show high prediction accuracy.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"7 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73433691","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}
Pub Date : 2010-05-23DOI: 10.1109/ICC.2010.5502177
Omar A. Nasr, O. Takeshita, Weijun Zhu, B. Daneshrad
the results of a field trials campaign in a park, a wide street, a narrow street and office environments are presented in this paper. The trials are carried out using a real time 4x4 MIMO-OFDM testbed working in the 2.4 GHz ISM band and a 20 MHz bandwidth. The testbed supports both spatial multiplexing and transmit and receive diversity. We compare the system performance using different number of spatial streams in different environments. We also determine the maximum number of spatial streams that can be supported in the indoor and outdoor environments respectively. We found that the maximum achievable throughput for the system in the indoor environment is almost double the maximum achievable throughput in the outdoor environment at the same receive power. This is mainly due to the richness of scattering elements in an indoor setting. Our outdoor trials showed that supporting more than two spatial streams will not introduce any throughput gain.
{"title":"Field Trial Results of a 4X4 MIMO-OFDM Real Time Testbed","authors":"Omar A. Nasr, O. Takeshita, Weijun Zhu, B. Daneshrad","doi":"10.1109/ICC.2010.5502177","DOIUrl":"https://doi.org/10.1109/ICC.2010.5502177","url":null,"abstract":"the results of a field trials campaign in a park, a wide street, a narrow street and office environments are presented in this paper. The trials are carried out using a real time 4x4 MIMO-OFDM testbed working in the 2.4 GHz ISM band and a 20 MHz bandwidth. The testbed supports both spatial multiplexing and transmit and receive diversity. We compare the system performance using different number of spatial streams in different environments. We also determine the maximum number of spatial streams that can be supported in the indoor and outdoor environments respectively. We found that the maximum achievable throughput for the system in the indoor environment is almost double the maximum achievable throughput in the outdoor environment at the same receive power. This is mainly due to the richness of scattering elements in an indoor setting. Our outdoor trials showed that supporting more than two spatial streams will not introduce any throughput gain.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"155 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73441563","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}
Pub Date : 2010-05-23DOI: 10.1109/ICC.2010.5502351
Daniel Medina, F. Hoffmann, F. Rossetto, C. Rokitansky
The Airborne Internet is envisioned to be a large scale multihop wireless mesh network of commercial passenger aircraft connected via long range highly directional air-to-air radio links. We propose a localized geographic load sharing technique to mitigate congestion in this network, taking into account the underlying link scheduling constraints with directional antennas. When forwarding packets for a given destination, a node considers not one but a set of next hop candidates, and spreads traffic among them based on queue dynamics. Our simulations show that introducing this flexibility in the routing function can greatly increase a node's ability to satisfy its bandwidth demands during link scheduling, yielding significant performance improvements in terms of network throughput and average packet delay.
{"title":"A Crosslayer Geographic Routing Algorithm for the Airborne Internet","authors":"Daniel Medina, F. Hoffmann, F. Rossetto, C. Rokitansky","doi":"10.1109/ICC.2010.5502351","DOIUrl":"https://doi.org/10.1109/ICC.2010.5502351","url":null,"abstract":"The Airborne Internet is envisioned to be a large scale multihop wireless mesh network of commercial passenger aircraft connected via long range highly directional air-to-air radio links. We propose a localized geographic load sharing technique to mitigate congestion in this network, taking into account the underlying link scheduling constraints with directional antennas. When forwarding packets for a given destination, a node considers not one but a set of next hop candidates, and spreads traffic among them based on queue dynamics. Our simulations show that introducing this flexibility in the routing function can greatly increase a node's ability to satisfy its bandwidth demands during link scheduling, yielding significant performance improvements in terms of network throughput and average packet delay.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"241 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73547961","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}
Pub Date : 2010-05-23DOI: 10.1109/ICC.2010.5502823
Zhe Chen, Yongyu Chang, Dacheng Yang
A novel spatial-multiplexing orthogonal frequency- division multiplexing (OFDM) transmission system with transmit diversity provided by space-frequency block code (SFBC) is proposed in this paper. The proposed scheme combines Alamouti scheme and Bell Labs layered space-time (BLAST) together, thus can achieve transmit diversity and spatial multiplexing gains altogether. Two-step iterative detection algorithm is also proposed for this system, in which MMSE detection is performed firstly and then SFBC decoding coupled with successive interference cancellation (SIC) is performed separately and iteratively for each layer. Simulation results show that the proposed system with iterative detection algorithm can achieve better tradeoff between transmission rate and bit error rate (BER) performance than existing multiple-input multiple-output (MIMO) OFDM systems.
{"title":"A Novel Spatial-Multiplexing OFDM System with Transmit Diversity Based on SFBC","authors":"Zhe Chen, Yongyu Chang, Dacheng Yang","doi":"10.1109/ICC.2010.5502823","DOIUrl":"https://doi.org/10.1109/ICC.2010.5502823","url":null,"abstract":"A novel spatial-multiplexing orthogonal frequency- division multiplexing (OFDM) transmission system with transmit diversity provided by space-frequency block code (SFBC) is proposed in this paper. The proposed scheme combines Alamouti scheme and Bell Labs layered space-time (BLAST) together, thus can achieve transmit diversity and spatial multiplexing gains altogether. Two-step iterative detection algorithm is also proposed for this system, in which MMSE detection is performed firstly and then SFBC decoding coupled with successive interference cancellation (SIC) is performed separately and iteratively for each layer. Simulation results show that the proposed system with iterative detection algorithm can achieve better tradeoff between transmission rate and bit error rate (BER) performance than existing multiple-input multiple-output (MIMO) OFDM systems.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"168 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75191828","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}
Pub Date : 2010-05-23DOI: 10.1109/ICC.2010.5502375
Jie Ding, J. Hillston, D. Laurenson
With the increasing diversity of content as well as user preferences, and the heterogeneity of devices and network technologies, content adaptation has been widely acknowledged as an effective strategy to deliver services and content to users in a variety of contexts. This paper presents an evaluation of the response time of large scale content adaptation systems being developed under the auspices of the Mobile VCE, using the high-level modelling formalism -performance evaluation process algebra (PEPA). The relevant factors of the system performance, including the operation speed of individual entities, loading and resource conditions of the system, are determined and analysed.
{"title":"Evaluating the Response Time of Large Scale Content Adaptation Systems Using Performance Evaluation Process Algebra","authors":"Jie Ding, J. Hillston, D. Laurenson","doi":"10.1109/ICC.2010.5502375","DOIUrl":"https://doi.org/10.1109/ICC.2010.5502375","url":null,"abstract":"With the increasing diversity of content as well as user preferences, and the heterogeneity of devices and network technologies, content adaptation has been widely acknowledged as an effective strategy to deliver services and content to users in a variety of contexts. This paper presents an evaluation of the response time of large scale content adaptation systems being developed under the auspices of the Mobile VCE, using the high-level modelling formalism -performance evaluation process algebra (PEPA). The relevant factors of the system performance, including the operation speed of individual entities, loading and resource conditions of the system, are determined and analysed.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"8 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75514640","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}
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