Overview of MPLS technology and traffic engineering applications

Abstract

Summary form only given. Multiprotocol label switching (MPLS) employs label information to identify packets, and, unlike conventional IP routing, forwards packets based on label information instead of the packet's IP destination address. Label switched routers (LSRs) use signaling protocols to establish label switched paths (LSPs). In general, LSPs can follow conventionally routed shortest paths or explicit paths that could be different from the shortest paths. When an LSP is established along an explicit path, it is referred to as a traffic engineered (TE) LSP. In addition to allowing high performance forwarding architectures, MPLS technology enables other important applications. MPLS, TE mechanisms in particular, are increasingly being deployed by service providers to guarantee quality of service (QoS), to utilize network resources efficiently and to protect data traffic against network failures. The tutorial includes the following: a brief introduction of fundamental components of the MPLS technology; a brief overview of RSVP (resource reservation protocol) and its traffic engineering enhancements; an illustration of how enhanced RSVP can be used to establish TE LSP; a brief overview of the MPLS fast reroute (FRR) mechanism which can be used to reroute traffic quickly against link/node failures. Some previous exposure to IP routing protocols may be useful, but is not required.