Duplicate Packet Detection for Multicast: Methods, Analysis, and Relative Performance

In many wireless multihop networks multicast is the dominant form of communication. In these networks, devices cannot depend on existing techniques to make forwarding decisions about the multihop multicast packets. Instead, devices must maintain state about packets that have already been forwarded to ensure they are not forwarded again. This procedure is known as duplicate packet detection (DPD). There are multiple solutions to this problem that follow the same general guidelines, but these solutions vary significantly in the resources consumed. This paper analyzes the various resources tradeoffs between the two most common approaches; a sequence number based approach (S-DPD) and an assisted hash based approach (H-DPD). This paper shows that S-DPD is superior or equal to H-DPD in terms of DPD state maintenance, energy consumption, and delay.