Transmitting Internet Protocol packets efficiently on underwater networks using entropy-encoder header translation

The Internet Protocol (IP) is ubiquitous in terrestrial and electromagnetic-carrier wireless networking. However, for very low-throughput underwater links (such as those using acoustic modems) the IP header introduces an unacceptable amount of data overhead for the small maximum transmission units available on underwater acoustic links. Nonetheless, it is becoming increasingly valuable to connect undersea deployments to the internet to provide data to researchers on shore, and facilitate remote command of deployed vehicles and sensors. This paper details a technique to reversibly translate the IPv4 header to allow IP packets to traverse acoustic links but with a header that is an order of magnitude smaller than a regular IPv4 header. In addition, this technique provides support for translating the User Datagram Protocol (UDP) header to provide scalable multiplexing. This technique works by dynamically partitioning the address space into the required subnet size based on the number of communicating nodes, and applying a Huffman entropy encoder to the address values based on the probabilistic data flow amongst the nodes.