Network Coding-Based Reliable IPv6 Packet Delivery Over IEEE 802.15.4 Wireless Personal Area Networks

Wireless personal area networks (WPANs) based on the IEEE 802.15.4 standard have been increasingly applied in vehicular and transportation-related applications. The 6LoWPAN protocol is used in delivering Internet Protocol version 6 (IPv6) packets over WPANs using the mesh-under routing (MUR) or route-over routing (ROR) mechanisms. When delivering an IPv6 packet over a multihop route consisting of unreliable links in a WPAN, the probability that the packet is successfully delivered at the destination, i.e., the packet delivery ratio (PDR), via MUR or ROR can be very small. This paper proposes the Reliable IPv6 Packet Delivery Scheme (RIPDS), which overcomes the aforementioned problem and considerably improves the PDR. RIPDS achieves a high PDR by use of network coding to encode the fragments of an IPv6 packet into multiple encoded packets, such that, regardless of the loss of some encoded packets, the original fragments and the original IPv6 packet can be still recovered by the node that receives some other encoded packets. The PDR and end-to-end packet latency under RIPDS, MUR, the controlled MUR (CtrMUR), and ROR are derived. Simulation results show that the proposed RIPDS outperforms the existing routing schemes such as ROR, MUR, and the CtrMUR, both in PDR and packet latency.