The Design And Implementation Of Embeded Software For OLT In40/10G TDM-PON Demo System

Nowadays, the Internet has become an indispensable part of people’s life. With the development of broadband services such as IPTV, HDTV, P2P video applications and large-scale network games, access bandwidth demand of users is increasing continually. So the operators of the telecommunication are rapidly developing next generation Passive Optical Network which has a large number of advantages, such as high transmission rate, wide cover scope and so on. Also NG-PON2has become a hot topic in the field of communication.40/10G TDM-PON conforms to the standard of NG-PON2with40Gbps downstream rate and40km transmission distance. So it can meet the future bandwidth demand of the access users and has significant research value.This paper researches the embedded software and QoS assurance technology of40/10G TDM-PON experimental system.The main work and innovative contributions in this paper are listed as follows.First, we design and implement the overall embedded software of OLT in40/10G TDM-PON demo system, including system operating requirements, functional requirements of the device, division of the embedded software module and functional design.Second, we analyze the requirement of switching function in the OLT and design the switching implementation scheme. Meanwhile we accomplish the driver and the configuration software of the switch chip. The experiment results show that the design achieves target demand.Third, a dynamic traffic balance algorithm based on apperception of traffic state in the network is proposed to solve the problem that the downstream bandwidth cannot be utilized fully in the OLT. This algorithm balances traffic timely on the basis of the curent network traffic state. The experiment results show that compared to conventional static traffic balance algorithm the dynamic traffic balance algorithm can effectively reduce network blocking probability and increase bandwidth utilization ratio.Forth, we analyze the cloud computing service feature whose traffic is increasing rapidly and the QoS assurance requirement of the downstream traffic in40/10G TDM-PON demo system. And a multi-service QoS assurance scheme which supports cloud computing service is proposed. This scheme achieves QoS assurance through setting priorities of services and using different queue scheduling policy. The experiment results show that the QoS assurance scheme can effectively guarantee the requirements of time delay, delay jitter and packet loss rate of every service.