BGP Confederation peerings

When implementing the BGP routing protocol, when configuring BGP Confederations, iBGP routers that belong to the same sub-AS must connect to each other either directly, or via another iBGP router in the same sub-AS. Peerings between iBGP routers that can reach each other through other sub-ASes cannot create iBGP peerings.

Links:

https://forum.networklessons.com/t/bgp-confederation-explained/1130/63?u=lagapides

https://networklessons.com/bgp/bgp-confederation-explained/