In some situations it be can attractive to have an authoritative DNS server that does not have a local copy of the zone or zones that it serves. In particular in anycast operations, it is sensible to have a great geographical and topological diversity. However, sometimes the expected use of a particular site does not warrant the cost of keeping local copies of the zones. This can be the case if a zone is very large or if the anycast cluster serves many zones from which only a few are expected to receive significant traffic. In these cases it can be useful to have a proxy serve some or all of the zones. The proxy would not have a local copy of the zones it serves, instead it forwards request to another server that is authoritative for the zone. The proxy may have a cache. This document describes the details of such proxies.