3. PCE for centralized traffic engineering

The limitations of distributed traffic engineering have prompted the industry to think about centralized traffic engineering. The idea is that a centralized computing element should be introduced to solve the problems of partial view, synchronous/dependent computing, optimization, and so on.

This centralized calculation component is called PCE (Path Computation Element). As its name suggests, its main function is to calculate paths according to the constraints and optimizations required.

Decoupling the calculation from the other functions of the control plan brings the following benefits:

• greater flexibility for operators in controlling their network;

• possibility of applying operator-related policies in path calculation (the code being potentially more open...