In this work, we focus on increasing network utilization to support real-time applications, especially voice over IP, in 802.11b wireless mesh network. For increasing capacity, we investigate on two directions: use of packet aggregation and utilize of header compression. Although aggregation reduces 802.11 MAC overhead, it also increases delay. We present a distributed multihop aggregation algorithm that uses the "natural" waiting time in the interface queue of packets in a loaded network. Header compression can relax the VoIP protocol overhead, but it also introduces the signaling overhead. In our work, we propose a zero-length header compression algorithm integrated with packet aggregation, which doesn't need to depend on the signaling mechanism to recover the context discrepancy between compressor and decompressor. The above performance optimization techniques are experimented in the NS2 simulator. The experimental results show an increase of 12 times for a six hop string when all optimizations are used.
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