Two medium-sized companies recently merged and would like to share their two campus buildings as soon as possible. Employees should be able to sit and work in either building. If the IP addresses in t

MPLS-VPN is an effective solution for overlapping address spaces but requires a full MPLS core with LDP signaling and PE/CE router configuration, making it too complex and slow to deploy quickly.

VRF-LITE creates independent virtual routing and forwarding tables on a single router or switch, keeping each company's overlapping IP subnets logically isolated within their own VRF instance. It requires no MPLS infrastructure and can be configured quickly on existing IOS-based equipment, directly satisfying both the overlapping address conflict and the speed-of-deployment requirements. Employees can access resources in either building while each address space remains completely separate.

EoMPLS extends Layer 2 connectivity over an MPLS core but does not resolve IP address overlap - bridging the two Layer 2 domains would place conflicting IP subnets on the same broadcast domain.

L2TPv3 tunnels Layer 2 frames over IP between sites but merging two Layer 2 domains with the same IP subnets would cause IP address conflicts rather than resolving them.