IP Traffic Engineering for Carrier Networks: Using Constraint-Based Routing to Deliver New Services

New Services IP networks offer unparalleled scalability and flexibility for rapid deployment of value-added IP services. However, with the increasing demand and explosive growth of the Internet, carriers require a network infrastructure that is dependable, predictable, and offers consistent network performance. Traffic engineering and differentiated services are the two cornerstones needed to achieve mission-critical networking. The MultiProtocol Label Switching (MPLS) approach proposed by the Internet Engineering Task Force (IETF) is to be the networking technology to deliver traffic engineering capability and QoS performance for carrier networks to support differentiated services. MPLS can deliver control and performance to IP data packets through the use of label switched paths (LSPs), in particular, with the use of explicitly routed LSPs (ER-LSPs). One protocol used to implement the ER-LSPs is Constraint-based Routing using Label Distribution Protocol (CR-LDP). This paper examines the functionality, performance, and implementation aspects of the CR-LDP signaling mechanism for ER-LSP implementation to support traffic engineering capabilities.