Admission control and dynamic routing schemes for wide-area broadband networks: their interaction and network performance

We consider wide-area broadband networks where multiple services with differing bandwidth requirements are offered (with peak rate allocation for the duration of a connection in a loss network environment). We present several dynamic routing schemes in such a multi-service setting along with an admission control policy. The routing schemes cover issues such as crankback, periodicity of computation of routing, and what type of information is used in routing decisions. We present results on their performance under normal as well as overloaded network conditions. We observe that in an integrated environment, for low-bandwidth service (such as voice), the various routing schemes provide similar performance; this is not so for high-bandwidth service (such as video) - we observe noticeable differences in the network performance for high-bandwidth service depending on whether the routing scheme has crankback, and how the routing decision is made. We also observe that the proper setting of the admission control scheme can reduce the discrepancies in blocking for different services.