I currently work on a system that connects several sites together using fixed leased lines. These leased lines for a ring topology for all our sites.
Each site has a wic-1t card ( per link ) and the local and opposite end of the link has a WAN ip address that is in the same subnet for that particular WAN link.
My questions is this ( hope its not too stupid !):
We are looking to migrate to an MPLS core network and hence each site will be as "close" to every other site and so on. My question is regarding the new WAN Ip- addresses and whether they will have to be in a different subnet for each site or will they all have to be in the same subnet ?
i.e would i potentially have WAn address es of 10.1.1.1 for site a
10.1.1.2 for site b
10.1.1.3 for site c
and so on in the same subnet.
Or, will it be:
site a wan address 10.1.1.1/30
site b wan address 10.1.1.5/30
site c wan address 10.1.1.8/30
and so on ?
I cant get my head round this and any advice is much appreciated...
The MPLS doesnt change any meaning of ip address schema else that in MPLS/VPN you can use overlap address with different VPNs,
Anyway regarding your question the branches WAN IPs have to be in a different subnet for each site as soon as they in the same VRF, the only deferent that your routers (CE) will peer with the ISP routers (PE) by /30 instead of peering every branch with the central or the hub router then the connectivity between each branch will be done through the ISP core network