http://www.rfc-editor.org/rfc/rfc2484.txt
RFC 2484: PPP LCP Internationalization Configuration Option, G. Zorn1999-01-01T23:00:00-00:00The Point-to-Point Protocol (PPP) provides a standard method for transporting multi-protocol datagrams over point-to-point links. PPP also defines an extensible Link Control Protocol (LCP), which allows negotiation of an Authentication Protocol for authenticating its peer before allowing Network Layer protocols to transmit over the link. [STANDARDS-TRACK]