A New Approach of Performance Improvement for Server Selection in Reliable Server Pooling Systems

Reliable server pooling (RSerPool) is a light-weight protocol framework for server redundancy and session failover, currently still under standardization by the IETF RSerPool WG. While the basic ideas of RSerPool are not completely new, their combination into a single, resource-efficient and unified architecture is. Server redundancy directly leads to the issues of load distribution and load balancing, which are both important for the performance of RSerPool systems. While there has already been some research on the server selection policies of RSerPool, an interesting question still remains open: Is it possible to further improve the load balancing performance of certain policies by simply letting servers reject inappropriately scheduled requests? In this case, the failover handling mechanisms of RSerPool could choose a possibly better server instead. The purpose of this paper is, after presenting an outline of the RSerPool framework, to analyse and evaluate the performance of our new approach. In particular, we also analyse the impact of RSerPool protocol parameters on the performance of the server selection functionalities as well as on the overhead.