RFC 8195 "Use of BGP Large Communities" was just now published:
RFC 8195 presents examples and inspiration for the operational
application of Large Communities. The document suggests logical
categories of Large Communities and demonstrates an orderly manner of
organizing community values within those categories to achieve typical
goals in routing policy. Any network or route server operator can
consider using the concepts presented as the basis for their own Large
RFC 8195 is meant as a companion document in the same way that RFC 1998
provided a concrete real-world application for RFC1997 BGP Communities.
The RFC draws on the experience of operator communities such as NANOG
A ton of open source implementations  with Large support are already
available. And with more traditional vendors like IOS XR, Junos, Arista
& Nokia having releases around the corner, I hope this will be useful
when planning your Large Communities deployment later this year.