Controlled Flooding of Fountain Codes

• Published in: IEEE transactions on wireless communications Vol. 16; no. 7; pp. 4698 - 4710
• Main Authors: Bin Abbas, Waqas, Casari, Paolo, Zorzi, Michele
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-07-2017; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: analysis; Analytical models; Coding; Computer simulation; Delays; Flooding; Floods; Fountain codes; heuristic policies; Network topologies; Packet transmission; Redundancy; Relays; restricted flooding; simulation; Spread spectrum communication; Wireless networks
• ISSN: 1536-1276; 1558-2248
• DOI: 10.1109/TWC.2017.2701822

We consider a multihop network where a source node must reliably deliver a set of data packets to a given destination node. To do so, the source applies a fountain code and floods the encoded packets through the network, until they reach their destination or are lost in the process. We model the probability that the destination can recover the original transmissions from the received coded packets as a function of the network topology and of the code redundancy, and show that our analytical results predict the outcome of simulations very well. These results are employed to design distributed forwarding policies that achieve a good tradeoff between the success probability and the total number of transmissions required to advance a packet toward the destination. We finally develop in detail the case where intermediate relays can inject additional redundancy in the network, provided that they have successfully decoded the source packets.