As you saw in Chapter 1, “Network Design Goals and Techniques,” one of the components of network availability is mean time to repair (MTTR)—how fast the network can react to, and route around, link or device failures. This chapter explores the relationship between high availability and fast convergence technologies in more depth. The chapter begins by analyzing the problems you will face when trying to deploy fast convergence. Then it discusses several techniques that have recently been developed to allow high availability and fast convergence, including these:
• Graceful restart
• Fast down detection
• Exponential backoff
• Speeding up route selection
The chapter concludes with coverage of how ...