pMORE: Exploiting Partial Packets in Opportunistic Routing

Opportunistic routing improves the performance of multi-hop wireless networks by exploiting the overhearing opportunities. However, without special hardware support, the current opportunistic routing protocols cannot exploit partial packets, i.e., packets with errors but still containing much useful information. In this paper, we present pMORE, a software-only opportunistic routing protocol capable of exploiting partial packets. pMORE performs random network coding at the granularity of blocks and uses block checksum test to efficiently locate correct information in a partial packet and avoid the risk of propagating errors. We design an algorithm to assemble packets with partial packets to add maximum fresh information while maintaining a low overhead. The experiment results from a 12-node indoor wireless testbed show that pMORE achieves higher throughput than MORE with a median throughput gain of 1.34×.