摘要 |
An interface (12, 14, or 16) in a service-provider network's transit label-switching router (P2) employs resource-management messages to inform neighbor routers of the bandwidths that it can allocate to various routes that it supports. To allocate its available bandwidth, it employs a weight value set for the route by an ingress router (PE2) in a system to which the label-switching router belongs. The transit router treats the weight as a relative bandwidth: when the sum of the bandwidths requested for various routes exceeds the bandwidth available, the router sets the bandwidths for at least some routes in accordance with the ratio of a given route's weight to the sum of the weights assigned to all routes among which it divides available bandwidth in this manner. That is, it assigns at least some bandwidth to all such routes, regardless of how small the resultant bandwidth may be. In this way, the network can operate with virtually no packet loss and yet remain available to all of its customers.
|