Advanced MPLS Design and Implementation

Chapter 6.  ATM-Based MPLS VPNs

This chapter covers the following topics:

• Introduction to ATM-Based MPLS VPNs—. Service providers and carriers that currently provide ATM and Frame Relay services can utilize their existing ATM infrastructure to provide managed VPN services using MPLS. IP transport over ATM networks requires a complex hierarchy of translation protocols to map IP addresses and routing into ATM addressing and routing. MPLS eliminates complexity by mapping IP addressing and routing information directly into ATM switching tables.

• MPLS and Tag Switching Terminology—. Tag Switching was Cisco's prestandard offering. Cisco has taken the initiative to be fully standards-compliant with respect to MPLS and has migrated many Tag Switching procedures ...