Chapter5.MPLS Design in MSS

Chapter 5. MPLS Design in MSS

This chapter covers the important points and steps when you're designing an MPLS network based on IP + ATM. MPLS extends the capability of an ATM switch to all devices in a network using IP + ATM. With IP routing integrated into ATM switches, you can provide support for scalable VPN services that can guarantee a Service-Level Agreement (SLA) for all traffic types. ATM switches have a very high degree of reliability and availability, which is fundamental to delivering QoS and high-availability networks. A key to successful deployment of MPLS in a multiservice switching network is to be able to guarantee SLAs for applications such as voice and video that require high uptime and that have strict latency and jitter bounds.

Reliability, availability, and serviceability (RAS) features are significantly more robust in switches that have parallel and redundant operating devices. Although redundancy is critical, high reliability, availability, and serviceability relate not only to minimizing failures and downtime but also to switch recovery time in the event of a failure, failure reporting, diagnostics, and carefully planned upgrades. Cisco ATM multiservice switches have been around for years and have proven RAS records.

This chapter concentrates on the fundamentals of ATM MPLS network design.

The main design steps for a robust working network are as follows:

• Designing and dimensioning ATM MPLS points of presence
  
  
• Dimensioning edge and backbone links in the network
  
  
• IP routing in ATM MPLS networks
  
  
• Label Switch Controller (LSC) redundancy
  
  
• Refining the design as soon as the network is operational
  
  

These steps are discussed in the following sections.