Research Of The Load Balancing Technology In The SIP Server Clusters

With the more and more drastic competition in the global communication market, nomatter what you are, the traditional Internet vendors or the fast growing mobile Internetvendors, you have to switch your role of a platform or pipe provider over to the role ofservice provider to stand out. It’s of vital importance to provide high quality service toenhance user stickiness, whereas building a high availability service platform is one of themost critical step. The mobile Internet service are controlled mainly by SIP, bringing outhigher demand for real-time feature. Thus, there exists many more challenges in systemthroughput and redundancy for the SIP server cluster system comparing with other clustersystem such as web cluster, database cluster and file system cluster.After researching on the existing commercial and open source project about the SIPserver cluster system, we know a lot about the detailed technology used in the system andalso find that there exists much room for improvement. Focusing on the key techniqueused in the SIP server cluster, a new load balancing algorithm is presented based on theadequate work of load balancing research. Also, we evaluate several load balancingalgorithm theoretically. To verify the performance of our new algorithm, we present thedesign, implementation and evaluation of our system using a cluster of Intel x86machinesrunning Linux. The main work includes the design and implementation of SIP loadbalancer and SIP server. The detailed test cases are presented for function test andperformance test.The load balancer in our system can distribute the SIP requests to the SIP serversevenly. When one of the load balancer crashes, the other backup server will take overseamlessly. Besides, the system is adapted to the SIP server’s dynamic change. The newalgorithm, least work left based on SIP transaction, achieves its performance bydynamically estimating the back-end SIP server load precisely.