5. Topological acquisition

5.1 Using IGP-TE

As in the distributed traffic engineering mode, the PCE can use an IGP-TE protocol adjacency (IS-IS or OSPF) to retrieve topological information from the network. The protocol's topology base synchronization process ensures that the PCE's topology is updated in real time.

The implementation of an IGP-TE adjacency generally requires a direct connection via an IP link between the two end nodes of the adjacency, due to the self-discovery of neighbors via multicast mechanisms. However, in the case of a PCE, it is possible that, for security reasons, it may be hosted in an area outside the network without the possibility...