How it works
THE GRH PROJECT HAS BEEN CONCLUDED
As IPv6 Routing Stability has improved over the years we have concluded the GRH project.
The GRH pages remain for a historical perspective.
The ULA Registry remains active.
GRH (Ghost Route Hunter) is a centralized mechanism for collecting routes and detecting the anomalies therein. We keep a history of these Ghost Routes providing a means of visualizing the problem. The ultimate target is to have no ghosts at all. As we have availability over several BGP tables we also collect prefix statistics and provide a distributed looking glass into these tables.
The previous system, which is currently still in use too, is documented under the Pre-Peering subtree.
The Ghost Route Hunting process has the following four steps:
A snapshot of all the collected tables are kept per hour in the archives.
The AFRINIC/ARIN/APNIC/LACNIC/RIPE DFP's are based on the 'stats' files provided by them on their FTP servers. These are also updated daily when new prefixes get allocated.
The ASN column in the DFP tables are determined based on the contents of the route6 entries found in the RIPE, ALTDB, RADB , APNIC, and JPIRR registries. This information is updated nightly. Additionally some ARIN whois entries contain an Origin ASN line, this information is used in case the route6 entries are not available, but this information is not automatically updated.
Countries where an ASN is present is based on the information found in the aut-num object and by merging inet6nums with route6 objects to come to a country overview. Most likely an ASN will be present in more than only the indicated countries. Also note that ASN's are not exclusively IPv6 only, information, especially from the aut-num might be indicative for IPv4 while a completely different routing topology, and thus country coverage, actually exists for IPv6.