Research On CoAP Reliable Multicast Protocol

In the Internet of things including the traditional Internet network and a kind of sensor network which is mainly composed of receiving terminal. The widely used HTTP protocol will not be able to apply to the limited resources of the network environment, so we need to introduce a new protocol for this network environment. In this background, IETF set up the CoRE working group, which is responsible for defining constrained in the limited network communication protocol-CoAP protocol.CoAP protocol can support reliable communication of unicast and multicast which is not reliable,but in some specific areas, the unreliable group communication may cause great trouble of communication. In this background, this paper aimed at the OMA’s three different scale cluster application scenario to carry on a detailed demand analysis, according to these scenarios,paper give using CoAP protocol communication’s solution, and points out that CoAP protocol multicast is unreliable.In order to solve the CoAP’s group communication reliability issues, this article adopts the way based on proxy server, and give out a reliable group communication system design about CoAP protocol. On the basis of the scheme, the author developed implements "CoAP reliable group communication simulation system".In view of the different receiving node number, the system which is based on a mixture of proxy server and unicast way to realize the construction of the system, provides the CoAP protocol reliable group communication scheme theory model and architecture.Finally, paper give out two aspects of function and performance test in view of the CoAP reliable group communication simulation system, and with this CoAP protocol reliable group communication scheme to proves reliable CoAP based on proxy server group communication is a kind of feasible implementing scheme.