BGP Communities use for the prefix origination tagging
BGP communities [RFC 1997] are 64-bit values that are used to tag the originated or traversing prefixes for the different purposes, such as origination tagging or policy application purposes. These values can be displayed in a new and old format, which notes different representation of the same 64-bit value. This document defines the way of tagging prefixes based upon their geographical origination to assist in development of geographically-based policies that, ideally, will result in RTD (Round Trip Delay) value improvements, as optimized paths can be established.