دانلود رایگان مقاله کدگذاری شبکه برای افزایش ارتباطات hop-by-hop در شبکه های چند هاپ

Abstract

In our recent study, we introduced the PlayNCool protocol that increases the throughput of the wireless networks by enabling a helper node to strengthen the communication link between two neighboring nodes and using random linear network coding. This paper focuses on design and implementation advantages of the PlayNCool protocol in a real environment of wireless mesh networks. We provide a detailed protocol to implement PlayNCool that is independent from the other protocols in the current computer network stack. PlayNCool performance is evaluated using NS–3 simulations and real-life measurements using Aalborg University’s Raspberry Pi test-bed. Our results show that selecting the best policy to activate the helper node is a key to guarantee the performance of PlayNCool protocol. We also study the effect of neighbor nodes in the performance of PlayNCool. Using a helper in presence of active neighbors is useful even if the channel from helper to destination is not better than the channel between sender and destination. PlayNCool increases the gain of end-to-end communication by two-fold or more while maintaining compatibility to standard wireless ad-hoc routing protocols.

8. Conclusions

In this paper, we introduced a routing independent protocol, called PlayNCool, to increase the performance of the wireless networks. PlayNCool exploits a local helper to fortify the gain of the individual link. The advantage of using a local helper is that it can use local information available in a specific link. In particular, the link quality between two relays and between relay and helper are the key factor to determine the gains provided by the PlayNCool. Besides, we showed that using a helper in the presence of active neighbors is useful even if the channel from helper to destination is not better than the channel between sender and destination. Our NS–3 simulations showed that PlayNCool increases the end-to-end gain by factor of two to four folds in the wireless mesh network. The implementation and measurements using Aalborg University’s Raspberry Pi testbed proved that the PlayNCool protocol decreases the total number of transmissions and the completion time. Our future work will focus on the using more helpers and also the effect of geographical position of the helper in the gain of the PlayNCool.