- The document describes a small MPLS VPN network with multiple vendor PE routers (Mikrotik, Cisco, Juniper).
- There is a minor bug in Mikrotik's BGP-VPNv4 implementation where the Route Distinguisher is propagated in reverse order, but this does not cause issues.
- The network uses OSPF or BGP between the PE and CE routers to distribute routes for different VPNs with unique Route Distinguishers and Route Targets.