中央研究院  |  資訊科學研究所  |  多媒體網路與系統實驗室
Toward an Understanding of the Processing Delay of Peer-to-Peer Relay Nodes
(NOTE: Sheng-Wei Chen is also known as Kuan-Ta Chen.)

Abstract
Peer-to-peer relaying is commonly used in real-time applications to cope with firewall restrictions and provide better quality network paths. As relaying is not natively supported by the Internet, it is usually implemented at the application layer. Also, in a modern operating system, the processor is shared, so the receive-process-forward process for each relay packet may take a considerable amount of time if the host is busy handling some other tasks. Thus, if we happen to select a loaded relay node, the relaying may introduce significant delays to the packet transmission time and even degrade the application performance. In this work, based on an extensive set of Internet traces, we pursue an understanding of the processing delays incurred at relay nodes and their impact on the application performance. Our contribution is three-fold: 1) we propose a methodology for measuring the processing delays at any relay node on the Internet; 2) we characterize the workload patterns of a variety of Internet relay nodes; and 3) we show that, although serious VoIP quality degradation may occur due to relay processing, the degradation is generally avoidable by predicting the workload of relay nodes.

Materials
Citation
Kuan-Ta Chen and Jing-Kai Lou, "Toward an Understanding of the Processing Delay of Peer-to-Peer Relay Nodes," In Proceedings of IEEE/IFIP International Conference on Dependable Systems and Networks (DSN), 2008.

BibTex
@INPROCEEDINGS{chen08:relay,
  TITLE      = {Toward an Understanding of the Processing Delay of Peer-to-Peer Relay Nodes},
  AUTHOR     = {Kuan-Ta Chen and Jing-Kai Lou},
  BOOKTITLE  = {Proceedings of IEEE/IFIP International Conference on Dependable Systems and Networks (DSN)},
  YEAR       = {2008}
}