BGP Confederation Explained

Hello Ernesto

You’re correct. The AS_CONFED_SET is indeed a path attribute that was previously utilized. However, as per the draft you linked, it is now recommended to deprecate the use of AS_SET and AS_CONFED_SET in BGP. This is due to the fact that these attributes can create routing loops if not managed correctly.

This draft is quite new, not even a half year old at the time of the writing of this post. Even so, it is possible the routers you’re using have updated their software to align with this recommendation, hence why you’re not seeing the AS_CONFED_SET attribute in Wireshark. What routers and IOS are you using?

I hope this has been helpful!