Constraint-Based Design of Extensible Networks

Advances in technology are making it increasingly attractive to incorporate specialized processing inside networks. Extensible networks enable network plugins to be dynamically loaded in routers, providing customized processing to individual application sessions. Examples of such processing include video compression, decompression and transcoding, general format conversions, and group information distribution. This paper addresses the question of how to design extensible networks to provide the bandwidth and processing resources needed to handle an expected traffic demand. The design of extensible networks is complicated by the fact that, in addition to dimensioning links to support traffic, processing resources must be allocated to support an expected traffic load. Since the use of extensible networks is driven by the applications that use them, the characteristics of those applications must be carefully considered in the network design process. This paper develops a framework for the design and configuration of cost-effective extensible networks that seamlessly integrates application characteristics and processing requirements into a general constraint-based network design methodology. We have incorporated these ideas into an interactive software design tool called the Extensible Network Planner(XNP), which enables convenient specification of network designs, rapid exploration of alternative designs and evaluation of those alternatives against automatically computed cost bounds. Constraint-Based Design of Extensible Networks Sumi Choi and Jonathan Turner Department of Computer Science and Engineering, Campus Box 1045 Washington University, St. Louis, MO 63130-4899 fsyc1, [email protected]