MPLS-Enabled Applications: Emerging Developments and New Technologies

14.2. THE BUSINESS DRIVERS

The driving force for the use of MPLS in the access network is network consolidation. Having one type of access technology allows more efficient use of fiber resources and reduces the quantity and different types of network devices required. Network consolidation has been occurring in the core part of service provider networks, with services from multiple separate networks being consolidated onto one common platform based on MPLS. Consolidation is now also occurring in the access part of the network, in order to avoid the CAPEX and OPEX associated with operating several access networks in parallel. Consolidation can also mean that fewer physical sites are required to house equipment, with traffic being carried to more centralized locations. Ethernet is an important ingredient of the new access network, replacing the various legacy Layer 2 and TDM access technologies that have been used in the past. It was realized that while Ethernet provides a convenient link technology for access networks, Layer 2 Ethernet switching is inherently unsuitable as an aggregation scheme for a carrier-class access network. Such a network can be achieved much more easily using MPLS, with Ethernet as the link technology. Additionally, because MPLS is independent of the link layer, transition from legacy access networks is made easier as MPLS nodes can support legacy interfaces as well as Ethernet interfaces. Having MPLS in both the core and the access network is simpler than ...