The Research And Improvement Of PPPoE Protocol

PPPoE protocol is based on two widely accepted standard : 802.3 Ethernet standard and point-to-point dial-up PPP protocol, it takes full advantage of the addressing capability of Ethernet technology, its essence is providing a logical point-to-point linkin the shared medium network, make each user in the Ethernet can establish logical PPP connection with broadband access server. Users don’t need to understand the LAN technology deeply, just take it as ordinary dial-up line, at the same time,operators do not need to spend a fortune to transform existing LAN structure.PPPoE is a currently widely used access protocol, providing a good mechanism of authentication, billing. Though nowadays the city network infrastructure is good, the access network broadly uses optical fiber, five types of twisted-pair cable which can support high bandwidth and large capacity transmission.However, in some special situations,such as the old network,access network link quality cannot be guaranteed.On the project’s demand and the need for this kind of network’s transformation,on account of the limitation of the actual conditions, this paper takes the method of network protocol optimization to serve special network scenarios. PPPoE protocol and the PPP has been introduced in this paper, analyzed the reson for network time delay and the difference between the network terminal equipments’ processing capacity, and put forward a dynamic delay tolerance mechanism according to the terminal’s link quality, improving the problem of link channel drops due to the network link quality,in addition propose a method to improve network link bandwidth utilization by PPPoE head compression and IP header compression.In the implementation part, for the server this paper puts forwarddistributed architecture of the separation of the controland forwarding module, which can be applied to large-scale routing access and improve the forwarding performance; for the clientit uses the embedded Linux, the program module is design to the main function in PPPoE protocol, making the code as short as possible.According to the actual applying scenarios, this paper simulates the similar scenario, the test shows that under the condition of the poor link quality the optimization of PPPoE protocol increase the number of online clients at the same time,and reduces the transmission delay and saves network bandwidth, meets project requirements as result.