One of the basic concepts when working with external BGP (eBGP) is the idea that if an eBGP speaker sees their own Autonomous System Number (ASN) in an update message, that eBGP speaker can assume a loop has occurred and it will discard the update. With internal BGP (iBGP) the requirement for loop freedom is still the same, but the implementation of how to make that happen is much different and a bit more complex. After completing the required reading on the Border Gateway Protocol (BGP), in addition to all of RFC 4456, discuss why it is necessary for BGP to offer different approaches to preventing loops when using iBGP. Compare and contrast the use of a full-mesh, Route Reflectors (RR), and confederations and provide a use case where each one might be most appropriate

https://datatracker.ietf.org/doc/html/rfc4456