Pub Date : 2009-07-13DOI: 10.1109/IWQoS.2009.5201390
A. Iyer, Gaurav Deshpande, Eric Rozner, Apurv Bhartia, L. Qiu
With the phenomenal growth of wireless networks and applications, it is increasingly important to deliver content efficiently and reliably over wireless links. However, wireless performance is still far from satisfactory due to limited wireless spectrum, inherent lossy wireless medium, and imperfect packet scheduling. While significant research has been done to improve wireless performance, much of the existing work focuses on individual design space. We take a holistic approach to optimizing wireless performance and resilience. We propose Fast Resilient Jumbo frames (FRJ), which exploit the synergy between three important design spaces: (i) frame size selection, (ii) partial packet recovery, and (iii) rate adaptation. While these design spaces are seemingly unrelated, we show that there are strong interactions between them and effectively leveraging these techniques can provide increased robustness and performance benefits in wireless LANs. FRJ uses jumbo frames to boost network throughput under good channel conditions and uses partial packet recovery to efficiently recover packet losses under bad channel conditions. FRJ also utilizes partial recovery aware rate adaptation to maximize throughput under partial recovery. Using real implementation and testbed experiments, we show that FRJ out-performs existing approaches in a wide range of scenarios.
{"title":"Fast Resilient Jumbo frames in wireless LANs","authors":"A. Iyer, Gaurav Deshpande, Eric Rozner, Apurv Bhartia, L. Qiu","doi":"10.1109/IWQoS.2009.5201390","DOIUrl":"https://doi.org/10.1109/IWQoS.2009.5201390","url":null,"abstract":"With the phenomenal growth of wireless networks and applications, it is increasingly important to deliver content efficiently and reliably over wireless links. However, wireless performance is still far from satisfactory due to limited wireless spectrum, inherent lossy wireless medium, and imperfect packet scheduling. While significant research has been done to improve wireless performance, much of the existing work focuses on individual design space. We take a holistic approach to optimizing wireless performance and resilience. We propose Fast Resilient Jumbo frames (FRJ), which exploit the synergy between three important design spaces: (i) frame size selection, (ii) partial packet recovery, and (iii) rate adaptation. While these design spaces are seemingly unrelated, we show that there are strong interactions between them and effectively leveraging these techniques can provide increased robustness and performance benefits in wireless LANs. FRJ uses jumbo frames to boost network throughput under good channel conditions and uses partial packet recovery to efficiently recover packet losses under bad channel conditions. FRJ also utilizes partial recovery aware rate adaptation to maximize throughput under partial recovery. Using real implementation and testbed experiments, we show that FRJ out-performs existing approaches in a wide range of scenarios.","PeriodicalId":231103,"journal":{"name":"2009 17th International Workshop on Quality of Service","volume":"252 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122489304","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 : 2009-07-13DOI: 10.1109/IWQoS.2009.5201399
Shibo He, Jiming Chen, Youxian Sun, David K. Y. Yau, N. Yip
A mobile sensor is used to cover a number of points of interest (PoIs) where dynamic events appear and disappear according to given random processes. It has been shown in [1] that for Step and Exponential utility functions, the quality of monitoring (QoM), i.e., the fraction of information captured about all events, increases as the speed of the sensor increases. This work, however, does not consider the energy of motion, which is an important constraint for mobile sensor coverage. In this paper, we analyze the expected information captured per unit of energy consumption (IPE) as a function of the event type, the event dynamics, and the speed of the mobile sensor. Our analysis uses a realistic energy model of motion, and it allows the sensor speed to be optimized for information capture. We present simulation results to verify and illustrate the analytical results.
{"title":"On optimal information capture by energy-constrained mobile sensor","authors":"Shibo He, Jiming Chen, Youxian Sun, David K. Y. Yau, N. Yip","doi":"10.1109/IWQoS.2009.5201399","DOIUrl":"https://doi.org/10.1109/IWQoS.2009.5201399","url":null,"abstract":"A mobile sensor is used to cover a number of points of interest (PoIs) where dynamic events appear and disappear according to given random processes. It has been shown in [1] that for Step and Exponential utility functions, the quality of monitoring (QoM), i.e., the fraction of information captured about all events, increases as the speed of the sensor increases. This work, however, does not consider the energy of motion, which is an important constraint for mobile sensor coverage. In this paper, we analyze the expected information captured per unit of energy consumption (IPE) as a function of the event type, the event dynamics, and the speed of the mobile sensor. Our analysis uses a realistic energy model of motion, and it allows the sensor speed to be optimized for information capture. We present simulation results to verify and illustrate the analytical results.","PeriodicalId":231103,"journal":{"name":"2009 17th International Workshop on Quality of Service","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122531349","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 : 2009-07-13DOI: 10.1109/IWQoS.2009.5201403
Yong Ding, Kanthakumar Pongaliur, Li Xiao
Many efforts have been devoted to maximizing network throughput in a multi-channel multi-radio wireless mesh network. Current solutions are based on either pure static or pure dynamic channel allocation approaches. In this paper, we propose a hybrid multi-channel multi-radio wireless mesh networking architecture, where each mesh node has both static and dynamic interfaces. We first present an Adaptive Dynamic Channel Allocation protocol (ADCA), which considers optimization for both throughput and delay in the channel assignment. In addition, we also propose an Interference and Congestion Aware Routing protocol (ICAR) in the hybrid network with both static and dynamic links, which balances the channel usage in the network. Compared to previous work, our simulation results show that ADCA reduces the packet delay considerably without degrading the network throughput. Moreover, the hybrid architecture shows much better adaptivity to changing traffic than pure static architecture without dramatic increase in overhead.
{"title":"Hybrid multi-channel multi-radio wireless mesh networks","authors":"Yong Ding, Kanthakumar Pongaliur, Li Xiao","doi":"10.1109/IWQoS.2009.5201403","DOIUrl":"https://doi.org/10.1109/IWQoS.2009.5201403","url":null,"abstract":"Many efforts have been devoted to maximizing network throughput in a multi-channel multi-radio wireless mesh network. Current solutions are based on either pure static or pure dynamic channel allocation approaches. In this paper, we propose a hybrid multi-channel multi-radio wireless mesh networking architecture, where each mesh node has both static and dynamic interfaces. We first present an Adaptive Dynamic Channel Allocation protocol (ADCA), which considers optimization for both throughput and delay in the channel assignment. In addition, we also propose an Interference and Congestion Aware Routing protocol (ICAR) in the hybrid network with both static and dynamic links, which balances the channel usage in the network. Compared to previous work, our simulation results show that ADCA reduces the packet delay considerably without degrading the network throughput. Moreover, the hybrid architecture shows much better adaptivity to changing traffic than pure static architecture without dramatic increase in overhead.","PeriodicalId":231103,"journal":{"name":"2009 17th International Workshop on Quality of Service","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121565897","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 : 2009-07-13DOI: 10.1109/IWQoS.2009.5201393
Ronghui Hou, K. Lui, Ka-Cheong Leung, F. Baker
In this paper, we consider the problem of routing with two additive constraints in the hierarchical networks, such as the Internet. In order for scalability, the supported QoS information in the hierarchical networks has to be aggregated. We propose a novel method for aggregating the QoS information. To the best of our knowledge, our approach is the first study to use the area-minimization optimization, the de facto optimization problem of the QoS information aggregation. We use a set of real numbers to approximate the supported QoS between different domains. The size of the set is predefined so that advertisement overhead and the space requirement will not grow exponentially as the network size grows. The simulation results show that the proposed method outperforms the existing methods.
{"title":"Routing with QoS information aggregation in hierarchical networks","authors":"Ronghui Hou, K. Lui, Ka-Cheong Leung, F. Baker","doi":"10.1109/IWQoS.2009.5201393","DOIUrl":"https://doi.org/10.1109/IWQoS.2009.5201393","url":null,"abstract":"In this paper, we consider the problem of routing with two additive constraints in the hierarchical networks, such as the Internet. In order for scalability, the supported QoS information in the hierarchical networks has to be aggregated. We propose a novel method for aggregating the QoS information. To the best of our knowledge, our approach is the first study to use the area-minimization optimization, the de facto optimization problem of the QoS information aggregation. We use a set of real numbers to approximate the supported QoS between different domains. The size of the set is predefined so that advertisement overhead and the space requirement will not grow exponentially as the network size grows. The simulation results show that the proposed method outperforms the existing methods.","PeriodicalId":231103,"journal":{"name":"2009 17th International Workshop on Quality of Service","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121904865","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 : 2009-07-13DOI: 10.1109/IWQoS.2009.5201415
Hemant Sengar, Xinyuan Wang, Haining Wang, D. Wijesekera, S. Jajodia
While network-wide anomaly analysis has been well studied, the on-line detection of network traffic anomalies at a vantage point inside the Internet still poses quite a challenge to network administrators. In this paper, we develop a behavioral distance based anomaly detection mechanism with the capability of performing on-line traffic analysis. To construct accurate online traffic profiles, we introduce horizontal and vertical distance metrics between various traffic features (i.e., packet header fields) in the traffic data streams. The significant advantages of the proposed approach lie in four aspects: (1) it is efficient and simple enough to process on-line traffic data; (2) it facilitates protocol behavioral analysis without maintaining per-flow state; (3) it is scalable to high speed traffic links because of the aggregation, and (4) using various combinations of packet features and measuring distances between them, it is capable for accurate on-line anomaly detection. We validate the efficacy of our proposed detection system by using network traffic traces collected at Abilene and MAWI high-speed links.
{"title":"Online detection of network traffic anomalies using behavioral distance","authors":"Hemant Sengar, Xinyuan Wang, Haining Wang, D. Wijesekera, S. Jajodia","doi":"10.1109/IWQoS.2009.5201415","DOIUrl":"https://doi.org/10.1109/IWQoS.2009.5201415","url":null,"abstract":"While network-wide anomaly analysis has been well studied, the on-line detection of network traffic anomalies at a vantage point inside the Internet still poses quite a challenge to network administrators. In this paper, we develop a behavioral distance based anomaly detection mechanism with the capability of performing on-line traffic analysis. To construct accurate online traffic profiles, we introduce horizontal and vertical distance metrics between various traffic features (i.e., packet header fields) in the traffic data streams. The significant advantages of the proposed approach lie in four aspects: (1) it is efficient and simple enough to process on-line traffic data; (2) it facilitates protocol behavioral analysis without maintaining per-flow state; (3) it is scalable to high speed traffic links because of the aggregation, and (4) using various combinations of packet features and measuring distances between them, it is capable for accurate on-line anomaly detection. We validate the efficacy of our proposed detection system by using network traffic traces collected at Abilene and MAWI high-speed links.","PeriodicalId":231103,"journal":{"name":"2009 17th International Workshop on Quality of Service","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128953483","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 : 2009-07-13DOI: 10.1109/IWQoS.2009.5201414
Yueping Zhang, V. Singh, Yu Gu, Guofei Jiang, Yu Ru
In the recent years, a progressively growing number of computing and communication services have undertaken the migration from their conventional media to the new unified platform, IP networks. As a consequence, business success of service providers becomes largely determined by the effectiveness of their service management schemes, which require rapid identification of problems and resolution of network-related anomalies. However, this is a non-trivial task in heterogeneous enterprise networks due to service providers' invisibility of the health and performance of the underlying carrier network. In addition, the gap between quality of service (QoS) measurements reflecting network performance and quality of experience (QoE) metrics indicating user-perceived service quality further makes effective service management more challenging. In this paper, we present a unified service management system called QoEScope, which combines scalable end-to-end probing, accurate topology inference in the presence of implicit routers, adaptive bridging between QoS measurement and QoE metrics, and intelligent root cause analysis. Extensive testbed emulations and Internet experiments demonstrate that QoEScope is a highly practical and effective IP service management solution for heterogeneous enterprise networks.
{"title":"QoEScope: Adaptive IP service management for heterogeneous enterprise networks","authors":"Yueping Zhang, V. Singh, Yu Gu, Guofei Jiang, Yu Ru","doi":"10.1109/IWQoS.2009.5201414","DOIUrl":"https://doi.org/10.1109/IWQoS.2009.5201414","url":null,"abstract":"In the recent years, a progressively growing number of computing and communication services have undertaken the migration from their conventional media to the new unified platform, IP networks. As a consequence, business success of service providers becomes largely determined by the effectiveness of their service management schemes, which require rapid identification of problems and resolution of network-related anomalies. However, this is a non-trivial task in heterogeneous enterprise networks due to service providers' invisibility of the health and performance of the underlying carrier network. In addition, the gap between quality of service (QoS) measurements reflecting network performance and quality of experience (QoE) metrics indicating user-perceived service quality further makes effective service management more challenging. In this paper, we present a unified service management system called QoEScope, which combines scalable end-to-end probing, accurate topology inference in the presence of implicit routers, adaptive bridging between QoS measurement and QoE metrics, and intelligent root cause analysis. Extensive testbed emulations and Internet experiments demonstrate that QoEScope is a highly practical and effective IP service management solution for heterogeneous enterprise networks.","PeriodicalId":231103,"journal":{"name":"2009 17th International Workshop on Quality of Service","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122566690","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 : 2009-07-13DOI: 10.1109/IWQoS.2009.5201392
Attila Korösi, Csaba Lukovszki, B. Székely, A. Császár
This paper investigates a VoD distribution architecture that exploits the increasing uplink and local storage capacities of customer equipment in a peer-to-peer (P2P) manner in order to offload the central video servers and the core network segment. We investigate an environment where (i) the peers' upload speeds vary in time and (ii) on the subscriber's downlink a strict bandwidth limit constrains the VoD delivery, and where (iii) this downlink limit is not significantly higher than the video's own bit rate while (iv) the subscribers' upload capacities are not cut down. In such an environment providing quality for a true VoD service requires carefully selected mechanisms. We show how the components (storage policy, uplink speed management) of a P2P-VoD system should be changed to be feasible under these conditions. The main component of the system determines the minimal required server speed as a function of the prebuffered content, the uploaders' behaviours, and the given play back fault probability. Additionally, by using simulation we investigate the optimal downlink bandwidth limit for a subscriber population with different average upload speeds.
{"title":"High quality P2P-Video-on-Demand with download bandwidth limitation","authors":"Attila Korösi, Csaba Lukovszki, B. Székely, A. Császár","doi":"10.1109/IWQoS.2009.5201392","DOIUrl":"https://doi.org/10.1109/IWQoS.2009.5201392","url":null,"abstract":"This paper investigates a VoD distribution architecture that exploits the increasing uplink and local storage capacities of customer equipment in a peer-to-peer (P2P) manner in order to offload the central video servers and the core network segment. We investigate an environment where (i) the peers' upload speeds vary in time and (ii) on the subscriber's downlink a strict bandwidth limit constrains the VoD delivery, and where (iii) this downlink limit is not significantly higher than the video's own bit rate while (iv) the subscribers' upload capacities are not cut down. In such an environment providing quality for a true VoD service requires carefully selected mechanisms. We show how the components (storage policy, uplink speed management) of a P2P-VoD system should be changed to be feasible under these conditions. The main component of the system determines the minimal required server speed as a function of the prebuffered content, the uploaders' behaviours, and the given play back fault probability. Additionally, by using simulation we investigate the optimal downlink bandwidth limit for a subscriber population with different average upload speeds.","PeriodicalId":231103,"journal":{"name":"2009 17th International Workshop on Quality of Service","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125319981","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 : 2009-07-13DOI: 10.1109/IWQoS.2009.5201411
Vipul Mathur, Preetam Patil, V. Apte, K. Moudgalya
The system capacity available to a multi-tier Web based application is often a dynamic quantity. Most static threshold-based overload control mechanisms are best suited to situations where the system's capacity is constant or the bottleneck resource is known. However, with varying capacity, the admission control mechanism needs to adapt dynamically. We propose and implement an adaptive admission control mechanism that adjusts the admitted load to compensate for changes in system capacity. The proposed solution is implemented as a proxy server between clients and front-end Web servers. The proxy monitors ‘black-box’ performance metrics-response time and rate of successfully completed requests (goodput). With these measurements as indicators of system state, we employ a control theory based feedback loop to dynamically determine the rate of admitted requests. The objective is to balance changes in response time and changes in goodput, while preventing overloads due to reduction in available system capacity. We evaluate our mechanism with experiments on a test-bed and find that it is able to maintain higher productivity than a static admission control scheme.
{"title":"Adaptive admission control for web applications with variable capacity","authors":"Vipul Mathur, Preetam Patil, V. Apte, K. Moudgalya","doi":"10.1109/IWQoS.2009.5201411","DOIUrl":"https://doi.org/10.1109/IWQoS.2009.5201411","url":null,"abstract":"The system capacity available to a multi-tier Web based application is often a dynamic quantity. Most static threshold-based overload control mechanisms are best suited to situations where the system's capacity is constant or the bottleneck resource is known. However, with varying capacity, the admission control mechanism needs to adapt dynamically. We propose and implement an adaptive admission control mechanism that adjusts the admitted load to compensate for changes in system capacity. The proposed solution is implemented as a proxy server between clients and front-end Web servers. The proxy monitors ‘black-box’ performance metrics-response time and rate of successfully completed requests (goodput). With these measurements as indicators of system state, we employ a control theory based feedback loop to dynamically determine the rate of admitted requests. The objective is to balance changes in response time and changes in goodput, while preventing overloads due to reduction in available system capacity. We evaluate our mechanism with experiments on a test-bed and find that it is able to maintain higher productivity than a static admission control scheme.","PeriodicalId":231103,"journal":{"name":"2009 17th International Workshop on Quality of Service","volume":"220 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133376832","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 : 2009-07-13DOI: 10.1109/IWQoS.2009.5201384
Jin Jin, Baochun Li
The Multicast and Broadcast Service (MBS) in WiMAX has emerged as the next-generation wireless infrastructure to broadcast data or digital video. Multicast scheduling protocols play a critical role in achieving efficient multicast transmissions in MBS. However, the current state-of-the-art protocols, based on the shared-channel single-hop transmission model, do not exploit any potential advantages provided by the channel and cooperative diversity in multicast sessions, even while WiMAX OFDMA provides such convenience. The inefficient multicast transmission leads to the under-utilization of scarce wireless bandwidth. In this paper, we revisit the multicast scheduling problem, but with a new perspective in the specific case of MBS in WiMAX, considering the use of multiple ODFMA channels, multiple hops, and multiple paths simultaneously. Participating users in the multicast session are dynamically enabled as relays and concurrently communicate with others to supply more data. During the transmission, random network coding is adopted, which helps to significantly reduce the overhead. We design practical scheduling protocols by jointly studying the problems of channel and power allocation on relays, which are very critical for efficient cooperative communication. Protocols that are theoretically and practically feasible are provided to optimize multicast rates and to efficiently allocate resources in the network. Finally, with simulation studies, we evaluate our proposed protocols to highlight the effectiveness of cooperative communication and random network coding in multicast scheduling with respect to improving performance.
{"title":"Cooperative multicast scheduling with random network coding in WiMAX","authors":"Jin Jin, Baochun Li","doi":"10.1109/IWQoS.2009.5201384","DOIUrl":"https://doi.org/10.1109/IWQoS.2009.5201384","url":null,"abstract":"The Multicast and Broadcast Service (MBS) in WiMAX has emerged as the next-generation wireless infrastructure to broadcast data or digital video. Multicast scheduling protocols play a critical role in achieving efficient multicast transmissions in MBS. However, the current state-of-the-art protocols, based on the shared-channel single-hop transmission model, do not exploit any potential advantages provided by the channel and cooperative diversity in multicast sessions, even while WiMAX OFDMA provides such convenience. The inefficient multicast transmission leads to the under-utilization of scarce wireless bandwidth. In this paper, we revisit the multicast scheduling problem, but with a new perspective in the specific case of MBS in WiMAX, considering the use of multiple ODFMA channels, multiple hops, and multiple paths simultaneously. Participating users in the multicast session are dynamically enabled as relays and concurrently communicate with others to supply more data. During the transmission, random network coding is adopted, which helps to significantly reduce the overhead. We design practical scheduling protocols by jointly studying the problems of channel and power allocation on relays, which are very critical for efficient cooperative communication. Protocols that are theoretically and practically feasible are provided to optimize multicast rates and to efficiently allocate resources in the network. Finally, with simulation studies, we evaluate our proposed protocols to highlight the effectiveness of cooperative communication and random network coding in multicast scheduling with respect to improving performance.","PeriodicalId":231103,"journal":{"name":"2009 17th International Workshop on Quality of Service","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131510562","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 : 2009-07-13DOI: 10.1109/IWQoS.2009.5201416
Hao Wang, Bill Lin
Priority queues are an essential building block for implementing advanced per-flow service disciplines at high-speed network links. In this paper, we propose novel solutions to the scalable implementation of priority queues by decomposing the problem into two parts, a succinct priority index in SRAM that can efficiently maintain a real-time sorting of priorities, coupled with a DRAM-based implementation of large packet buffers. In particular, we propose three related novel succinct priority index data structures for implementing high-speed priority indexes: a Priority-Index (PI), a Counting-Priority-Index (CPI), and a Pipelined Counting-Priority-Index (Pipelined CPI). We show that all three structures can be very compactly implemented in SRAM using only Θ(U) space, where U is the size of the universe required to implement the priority keys (timestamps). We also show that our proposed priority index structures can be implemented very efficiently as well by leveraging hardware-optimized instructions that are readily available in modern 64-bit microprocessors. The operations on the PI and CPI structures take Θ(logW U) time, where W is the processor word-length (i.e., W = 64 bits). Alternatively, operations on the Pipelined CPI structure take constant time with only Θ(logW U) pipeline stages. Finally, we show the application of our proposed priority index structures for scalable management of large packet buffers at line speeds.
{"title":"Succinct priority indexing structures for the management of large priority queues","authors":"Hao Wang, Bill Lin","doi":"10.1109/IWQoS.2009.5201416","DOIUrl":"https://doi.org/10.1109/IWQoS.2009.5201416","url":null,"abstract":"Priority queues are an essential building block for implementing advanced per-flow service disciplines at high-speed network links. In this paper, we propose novel solutions to the scalable implementation of priority queues by decomposing the problem into two parts, a succinct priority index in SRAM that can efficiently maintain a real-time sorting of priorities, coupled with a DRAM-based implementation of large packet buffers. In particular, we propose three related novel succinct priority index data structures for implementing high-speed priority indexes: a Priority-Index (PI), a Counting-Priority-Index (CPI), and a Pipelined Counting-Priority-Index (Pipelined CPI). We show that all three structures can be very compactly implemented in SRAM using only Θ(U) space, where U is the size of the universe required to implement the priority keys (timestamps). We also show that our proposed priority index structures can be implemented very efficiently as well by leveraging hardware-optimized instructions that are readily available in modern 64-bit microprocessors. The operations on the PI and CPI structures take Θ(logW U) time, where W is the processor word-length (i.e., W = 64 bits). Alternatively, operations on the Pipelined CPI structure take constant time with only Θ(logW U) pipeline stages. Finally, we show the application of our proposed priority index structures for scalable management of large packet buffers at line speeds.","PeriodicalId":231103,"journal":{"name":"2009 17th International Workshop on Quality of Service","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116802619","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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