http://www.rfc-editor.org/rfc/rfc2073.txt
RFC 2073: An IPv6 Provider-Based Unicast Address Format, Y. Rekhter, P. Lothberg, R. Hinden, S. Deering, J. Postel1997-01-01T23:00:00-00:00This document defines an IPv6 provider-based unicast address format for use in the Internet. [STANDARDS-TRACK]