PeeringDB
PeeringDB is "a freely available web-based database of networks that are interested in peering", which has become the default location for Internet peering data.
It was written by Richard Steenbergen, is run by various administrators on dedicated instances with a Cloud Provider and, like Wikipedia, consists of user contributed data. Almost one third of the critical default-free zone ASNs at least partially register their interconnection options in the database.History
Traditionally a list of potential peering partners would have been maintained by the host Internet exchange point or colocation centre, but these lists lacked important information such as peering policies and were difficult to keep up-to-date. Being a distributed database, it was also necessary for peers to consult multiple lists in order to establish peering relationships. PeeringDB has become the "first stop when deciding where and whom to peer with".
