I have a Cisco 1841 branch router with a WIC T1-DSU card. We have a MPLS through a local ISP with a T1 handoff.
The current config for our serial interface is as follows:
no ip address
encapsulation frame-relay IETF
interface Serial0/0/0.1 point-to-point
ip unnumbered BVI1
frame-relay interface-dlci 16
ip address 172.31.1.5 255.255.255.0
bridge 1 protocol ieee
bridge 1 route ip
I did not configure this router, so I would like to know what the logic behind this is? Do I need the BVI1 virtual interface or could I just put the IP addy on the sub-interface (what is best practice)?