Session awareness issues for next generation cluster based network load balancing frameworks

While a lot of researches focused on how to efficiently spread the offered network load on the available cluster resources, less interest has been granted to the impact of the used mechanisms on the reliable execution of the upper layer services. On the other hand, emerging NGN services as well as some of the already familiar services involve multiple flows during the lifespan of a single end- to-end session, hence, raising the challenge of session awareness while processing the incoming network traffic. In this paper, we grasp the need for fine grained session awareness to efficiently allocate the cluster resources to the offered network traffic. The analysis of load balancing scenarios of some representative IP services provides us with solid reasons to use deep packet inspection to achieve fine grained network traffic load distribution, and to meet NAT and firewall traversal constraints as well.