WHY SEAMLESS MPLS?
MPLS currently offers several features like LDP extensions for inter area LSPs, intra and inter area RSVP-TE, LDPoRSVP and PW switching (Multi-segment PW) which may be implemented to support end-to-end MPLS services. These features do not completely address the flexibility, scalability, resiliency and manageability of end-to-end MPLS networks. Enter Seamless MPLS - An IETF Working Group initiative. Seamless MPLS offers a superior alternative for implementing end-to-end MPLS networks. It describes an architecture that can be used to extend MPLS networks to integrate access, aggregation and core networks into a single MPLS domain. Seamless MPLS is not a new protocol suite. It is based on existing protocols (like BGP and LDP) and therefore provides a logical and easy evolution path. Seamless MPLS provides a robust framework which enables seamless, scalable and resilient end-to-end MPLS services.
SEAMLESS, SCALABLE AND RESILIENT
First, Seamless MPLS makes deploying services faster and more flexible. Existing MPLS networks are typically implemented and operated as separate networks (i.e. Core, aggregation or access). MPLS Services on the other may have end points within a metro network or need to cross from one metro network to the other. Creating Services across metro networks requires provisioning of multiple segments and end points which requires co-ordination at the network boundaries. Seamless MPLS removes domain boundaries and extends the topology into a single MPLS domain, so service can be deployed faster and between any two points (Seamless) in the end-to-end MPLS network. Next, it provides the kind of scale today’s networks need. Evolving to end-to-end MPLS networks results in networks with a significantly larger number of MPLS nodes. In particular, access nodes (Cell Site Routers, DSLAMs, Ethernet CPE) make up the largest number of nodes. Additionally these access nodes may not have the same functionality as aggregation or core MPLS nodes. In order to obtain a highly scalable architecture Seamless MPLS helps scale the end-to-end network to more than 100,000 MPLS devices, recognizing that access nodes have limited capabilities and therefore keeps access node functionality as simple as possible. And finally, it enables a highly resilient and manageable end-to-end network. Seamless MPLS supports end-to-end fault detection, fast protection and end-to-end operations, administration and maintenance (OAM) functions. This end-to-end visibility and recovery from faults provides reduced service downtime which is critical for end users. Several large service providers have already implemented Seamless MPLS within their networks. Many operators are now evaluating Seamless MPLS for mobile backhaul architectures and for evolution to converged (intra-AS or inter-AS) MPLS architectures. The technical considerations for implementing a Seamless MPLS network may include evaluating existing network equipment for seamless MPLS features support, as well as interoperability testing across multi-vendor equipment within the metro and core regions. Seamless MPLS will continue to play a crucial role in transforming the metro network to meet the increasing demand for video, mobile broadband and Cloud services.
FIND OUT MORE
Read the Seamless MPLS paper 'Evolving to "End-To-End MPLS" Architectures' for additional details. This paper reviews the motivation, architecture and building blocks required to implement a Seamless MPLS network. In addition it describes alternate interim options for deploying end-to-end MPLS networks. Alcatel-Lucent’s IP Routing solution, offers a complete toolkit to implement “end-to-end MPLS” networks. To contact the author or request additional information, please send an email to firstname.lastname@example.org.