http://www.rfc-editor.org/rfc/rfc2023.txt
RFC 2023: IP Version 6 over PPP, D. Haskin, E. Allen1996-10-01T23:00:00-00:00This document defines the method for transmission of IP Version 6 [2] packets over PPP links as well as the Network Control Protocol (NCP) for establishing and configuring the IPv6 over PPP. [STANDARDS-TRACK]