Research And Application Of TCP Protocol Reduction In Embedded Internet Environment

With the combination of embedded systems and network technologies, bringing TCP/IP protocol stack into embedded systems to connect embedded systems with Internet has become an important research direction in embedded fields.TCP/IP is the most basic protocol of Internet, and it has already been the actual industry standard due to its practicability and efficiency. To exchange information between embedded devices and Internet, we must support TCP/IP in embedded devices. However, TCP/IP protocol suit, especially for TCP is so complicated that it needs an amount of program space and data space to implement. But the available resources are very limited in embedded Internet environment, it is very difficult to implement TCP/IP in this condition. Traditionally, we can transplant the entire TCP/IP implementation by extending system resources and using high performance processors to solve this problem, but this raises the system price and limits the system's application scope.TCP is the most important and complicated protocol in TCP/IP protocol stack. In general, the TCP implementation has the 40 percent codes of the TCP/IP implementation and consumes most resources. A kind of TCP reduction method is presented in this paper based on the analysis on several TCP/IP implementations and the peculiarity of embedded Internet applications. This reduction method puts emphasis on reducing the numbers of status in TCP state machine, deleting unimportant and unnecessary state in embedded Internet environment, simplifying the complex relations, reducing the time of TCP connections. This method simplifies the complex process and decreases the status numbers in TCP state machine, so it can not only reduce the TCP implementation codes greatly but improve the system processing efficiency as well. At the same time, all these reductions are completely transparent for user because the user interfaces are untouched.At last, according to this reduction method, we modified the TCP implementation of WebitOS. Its integrality and processing efficiency is compared with the previous...