The Analysis And Deployment Of QoS Strategy In Beijing Telecom IP Metr-Area Network

ISPs need to implement QoS function in their networks to meet customers requirements. As a guide of QoS deployment, a series of QoS parameters, include traffic type, service category, bandwidth allocation and priority have been defined by China-telecomm. Based on all these requirements mentioned above, the paper is focused on the method of how to make QoS works on the Juniper router by software engineering solution.The network modeling and scenario is under native IP environment and based on Diffserv mode. The other three QoS metrics (delay, jitter and package loss rate) is not emphasized on this paper due to the current technical limitation.Beginning from software architecture studying, this thesis analyzed Juniper router's software architecture which is BSD UNIX + JUNOS. JUNOS contains multiple processes, all QoS involved operations is related with a daemon named as "forwarding process" which run in package forwarding engine, the network operators can input any QoS control instructions by command line interface (CLI), CLI is a kind of Man-Machine interface.The QoS control instructions is a proprietary, router-specific computer language that is similar to C: process-oriented, structural arithmetic, non-numerical computation, function-based, and special data structure, etc.The studying gives us a QoS solution on Juniper router followed on software lifecycle model: issue definition, requirements analyzing, high-level design, coding, testing and implementation.The studying has been tested by Lab successfully and deployed in Beijing telecom metro-area network in Q2 2008.