PE1-P1-P2-P3-P4-PE2if we know that the MTU in one of the backbone link srunning mpls is smaller than of ther others. then we want to check the MTU workable on this MPLS cloud,then we ping from PE1 with different packet size and DF set to PE2, then sh...

CE1-CE2-PE1-P-P-PE2-CE3-CE3For OSPF superbackbone:From CE2 perspective, PE1 is a ABRFrom provider network perspective, PE1 and PE2 is a ASBR.But for Provider network, how they see CE2?and Do CE1(in other area) still see PE1 as a ABR?