Performance evaluation of wireless mesh networks using IEEE 802.11s and IEEE 802.11n

With the recent approval of IEEE 802.11n standard and progress on IEEE 802.11s mesh standardization efforts, performance evaluation of such standards has gained acceleration. In particular, several wireless testbeds have been created to form wireless mesh networks (WMNs) in order to test various aspects of these new standards. However, none of these considered multi-hop performance of WMNs when 802.11n based nodes are employed. While IEEE 802.11s is geared for implementing multi-hopping capability among the nodes, current studies still assume IEEE 802.11a/g based nodes. This paper presents a performance evaluation of WMNs using both 802.11s (in conjunction with 802.11a/g) and 802.11n on a real academic testbed. While a draft version of 802.11s has been used for creating a linear WMN using 802.11a/g based routers, the same linear WMN using 802.11n has been created using virtualized interfaces at the IP layer. Using such WMNs, throughput performance of TCP and UDP at both the 2.4 GHz and 5 GHz spectrums with different number of hops has been examined. The experiment results have shown that multi-hopping significantly degrades the expected performance of IEEE 802.11n.