IP aggregation/sumerisation breaks an LSP into 2 segments

  • Aggregation should not be used where end-to-end LSP’s are required such as witin;
  • MPLS enabled ATM network
  • Transit BGP where core routers are not running BGP

Label allocatation and distribution in a frame-mode MPLS network follows these steps;

  • IP routing protocol build the IP routing table
  • Each LSR assigns a label to every destination in the IP routing table independently
  • LSRs announce their assigned labels to all other LSRs
  • Every LSR builds its LIB, LFIB and FIB data structures based on received labels