Conditional bandwidth subscriptions for multiprotocol label switching (MPLS) label switched paths (LSPs)

摘要

A method and system for providing conditional bandwidth subscriptions to MPLS LSPs. Traffic is policed and/or marked at an ingress node to ensure that traffic that exceeds the LSP's conditional bandwidth is dropped. Traffic above the LSP's committed bandwidth but below the LSP's conditional bandwidth is admitted but marked as suitable for discarding. All traffic below the LSP's committed bandwidth is admitted. A queuing mechanism at each node of the LSP helps ensure that committed bandwidth traffic is protected during periods of congestion. Each node maintains a queue with a first area reserved for periods of congestion and a second area reserved for periods of no congestion. When congestion is encountered, unmarked traffic is stored in the first area and marked traffic is discarded. When no congestion is encountered, both marked and unmarked traffic is stored in the second area.