RE: Router with 2 (or more) interfaces in same network

I am curious to know if its possible to have a router with its
two interfaces, say configured as, and
Theoretically, i see nothing which can stop a router from doing this.

Cisco's don't let you do this. I have always considered that
broken, although I'm sure Cisco thinks it's a feature.

bridge irb

inte f5/0
no ip add
bridge group 1

inte f5/1
no ip add
bridge group 1

inte bvi 1
ip add

bridge 1 prot ieee
bridge 1 route ip
bridge 1 bridge ip