Traffic Engineering with MPLS

Chapter 4. Path Calculation and Setup

Chapter 3, “Information Distribution,” asked these questions: How does MPLS Traffic Engineering really work? What are the underlying protocols, and how do they all tie together? And, most importantly, what do you need to type on your router to make all this wonderful stuff come to life?

Chapter 3 broke MPLS Traffic Engineering into three paths:

• Information distribution

• Path calculation and setup

• Forwarding traffic down a tunnel

This chapter, as you can tell from the title, is about the second part—path calculation and setup.

Path calculation and setup are two different things. Functionally, the code that decides what path a tunnel takes across your network is different from the code that actually sets up this ...