The return of EGP or the curious case of the BGP Origin attribute (denog17)

The BGP Origin attribute has been around for decades and did not attract much attention. It is simply there, shown either as "?" for "incomplete" or as "i" for IGP. During writing slides for my BGP training I found a large number (868) of prefixes in the global routing table tagged with "e" for EGP. The presentation does not give any answers but simply raises the question who and why is playing with that attribute. Licensed to the public under http://creativecommons.org/licenses/by/4.0 about this event: https://pretalx.com/denog17/talk/ASAQKE/