BGP - Peering, AS'es, and what is Comcast doing?

Hey all,

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I've used Comcast's DIA product (EDI) over several jobs and while I'm well versed in enterprise networking, most of the carrier magic is....well magic to me.

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Mostly for my own knowledge but I'm curious why/how this happens. I peer with AS7922, however looking at the BGP paths, or here - https://bgp.he.net/AS33668#_peers I see that AS33668 sits between me, and 7922. Why is that happening and what's the reasoning behind it?

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Looking at the HE output, it's clear that AS33668 is for Michigan, so at least that makes sense, but why don't I peer with that AS, and not 7922? Easier for them to manage on their end and they do the proper overrides in the AS path?