A Reliable SLA-based Admission Controller for MPLS Networks

This paper introduces a reliability conscious admission controller for enterprise level data networks. It builds upon earlier work on adaptive admission controllers designed to optimize utility (often revenue) in a data network. This was generally accomplished by using service level agreements (SLAs) to describe user requirements, and developing techniques for optimally accommodating a subset of all the SLAs requests for admission. Such admission problem can be mapped to a variant of the classic Knapsack problem. The controller introduced here, called the reliable SLA optimizer (R-SLAOpt), extends the previous model to make provisions for improved reliability. For instance, an SLA must be allocated to a new path in the event of a link failure. To accomplish this SLA adaptation, alternate paths are pre-calculated and therefore these paths can be quickly selected and activated. This makes R-SLAOpt a far more appropriate model for time critical applications, such as managing multimedia sessions.