The Research And Development Of CoAP Over TCP

The CoAP protocol is a restricted resource application protocol. In the CoAP protocol research and application, the default CoAP protocol stack use UDP as the transport layer?In the Ethernet environment, data transmission will be affected because of the existence of the firewall. For the reason that CoAP can be better applied to the current Internet environment and cloud environment, IETF working group proposed CoAP over TCP,CoAP protocol stack use TCP as the transport layer .In this context, CoAP over TCP is studied and CoAP over TCP is implemented based on the open source framework Californium. The CoAP over TCP is implemented as a client in the real Internet environment and the function of the implementation is evaluated. CoAP over TCP is the Internet of Things cloud platform services, so AWS environment is used to achieve CoAP over TCP / TLS and the default protocol stack performance comparison.In this paper, the significance of CoAP over TCP is expatiated, and CoAP over TCP is studied. After that, the overall architecture of Californium framework is deeply analyzed, and the design scheme of CoAP over TCP is proposed. The transport layer is extended on the basis of the original frame structure. Based on the design scheme, the modules are designed and designed in detail. On the core of the class through the class diagram describes the expansion of the relationship between the various modules. The network layer, protocol layer and application layer implementation process are analyzed in detail. Afterwards, we study the proxy between CoAP over TCP and default protocol stack, and propose the message type conversion problem and solution of CoAPToCoAP proxy.The paper concludes the relevant work, and puts forward the research direction of the next step.