Optimized Instantly Decodable Network Coding Protocols with Unequal Error Protection

Instantly Decodable Network Codes are of great interest in broadcast applications because of their properties like low decoding delay, low encoding and decoding complexities, and simple receiver requirements. This work explores two different multicast broadcast scenarios and gives instantly decodable index codes that perform better than codes in existing literature. First, we describe our novel Unequal Error Protection scheme that achieves theoretical optimality and illustrate it through examples. In order sensitive or delay sensitive applications, based on an earlier decodability at the receivers' end, a packet can be classified as high priority (HP) packets or low priority (LP) packets. We introduce a practical algorithm that improves the packet retransmission technique of Muhammed et al. (Proceedings of the 2013 IEEE International Conference on Communications (ICC), Budapest, pp. 5120-5125) for reliable multicast in the instantly decodable network coding framework. Our scheme improves the delay and total completion time by optimizing the number of instantly decodable network code packet transmissions from the source. Further, simulation results with a comparative study show considerable improvement in Quality of Experience (QoE) for the end-users.