Design And Implementation Of Fast Transition System Based On 802.11R

Nowadays, the whole world communication technology has become more and more popular and develops quickly. But it has become unable to meet the rising demand of the network because of the complication of the cable technology and the uselessness in a mobile network. With people’s rising demand for the wireless network, the development of wireless network has been far beyond the original cable communication technology. Though wireless network do es not have to build equipment and lines, it can easily cover the place where the wired network is unaccessible. Today, wireless network has stepped from analog communic ations period into the period of digital communications, a lot of equipments in our lives have joined the family of wireless terminal.Recently, with the popularity of wireless network, people’s demand of wireless communication quality is increasing. Because of the covered area of the wireless network is limited, when people are using a wireless network, roaming is inevitabl, especially in public and large areas. So if the wireless terminal devices can quickly cut off the connection with the current wireless access point, and then create links with another wireless terminal, it will seriously affect user’s experience. This switching delay between channels or wireless access points will reach more than 50 ms, which may lead to the loss of current connection, degradation of network quality and other issues.To figure out the problem that switching delay is too long, this paper is accordance to 802.11 R protocol standard of IEEE Committee, and uses the company’s existing environment and equipment, researches and achieves the fast transition system of 802.11 R protocol. This paper is based on the needs analysis departure of the standard, presents this system that should implement the basic functional requirements and technical conditions demand, and then discusses the detailed design of each functional module of 802.11 R fast transition system. The combination of each module is mainly to complete fast transition between ACs and within AC, to support fast roaming in over-the-air and over-the-ds in two ways, and to make sure that the fast transition system does not affect the operation and implementation of other functions.Then according to the detailed design part of functional view, the article talks about the detail implementation of the 802.11 R fast transition system, showing the structure and content of the main stages of fast transition’s wireless packets. At last, according to four aspects to test system, i.e.the function test, the combined test, performance test and protocol conformance test. The function test mainly test the achievement of all major functions; performance test mainly concerns if the system achieves the standard of fast transiton; combination test mainly test if the implementation of the system would affect other functions of the operating platform; protocol conformance test mainly concerns that if the system returns the correct state code under the influence of an error message. The system passed all the test methods and has achieved the expected standards.