[RedIris.es] Graph of OpenPGP keyservers relationships

Originally posted by me on GnuPG-Users mailing list.
Legend (thanks to [francisco.monserrat@rediris.es]):
Gray: No information on server type
Blue: Servers that have forwarded information to RedIris, pkcd
Red: LDAP servers at NAI/PGP Inc.

Full graph:
https://www.rediris.es/keyserver/keyserver.png