Network Coding forWireless Mesh Networks: A Case Study

Authors:

• Anway Al Hamra, Chadi Barakat, and Thierry Turletti

Complete Citation

Al Hamra, A., Barakat, C., and Turletti, T. 2006. Network Coding for Wireless Mesh Networks: A Case Study. In Proceedings of the 2006 international Symposium on on World of Wireless, Mobile and Multimedia Networks (June 26 - 29, 2006). International Workshop on Wireless Mobile Multimedia. IEEE Computer Society, Washington, DC, 103-114. DOI= http://dx.doi.org/10.1109/WOWMOM.2006.78

Abstract

Network coding is a new transmission paradigm that proved its strength in optimizing the usage of network resources. In this paper, we evaluate the gain from using network coding for file sharing applications running on top of wireless mesh networks. With extensive simulations carried out on a simulator we developed specifically for this study, we confirm that network coding can improve the performance of the file sharing application, but not as in wired networks. The main reason is that nodes over wireless cannot listen to different neighbors simultaneously. Nevertheless, one can get more from network coding if the information transmission is made more diverse inside the network. We support this argument by varying the loss rate over wireless links and adding more sources.

Annotations

In this paper the authors perform a case study on the effectiveness of network coding in a wireless mesh network. I liked this paper because it gives a very good overview of network coding and how it works. In their simulations they compare four different types of transmission protocols:

• blind forwarding - all nodes forward all data they receive --- no network coding.
• blind forwarding with network coding - anytime a new pair of data is received, the data is coded and retransmitted to the neighbors
• Selective forwarding - only forwards nodes "of interest" to its neighbors.
• selective forwarding with network coding - transmits a network coded chunk of all data.

Their simulations show (unsurprisingly) that the SF-NC scheme will allow the shortest amount of time before all neighbors receive the data. Overall, I do not believe their simulations are that interesting. Plus, the SF schemes are very unrealistic as in this case each node is required to know what all of their neighbors are interested in seeing. This is not addressed in this paper. So, while I feel that this paper gives a good overview of network coding, it does not do a good job of convincing me of the practicality.

-- DavidSalyers - 12 Dec 2007