RFC 4282:The Network Access Identifier
RFC-Ref

Point-to-Point Tunneling Protocol


Click on the red underlined text to get to the source

... tunneling protocols such as the Point-to-Point Tunneling Protocol (PPTP) [RFC2637], the Layer 2 ...


... Hamzeh, K., Pall, G., Verthein, W., Taarud, J., Little, W., and G. Zorn, "Point-to-Point Tunneling Protocol", RFC 2637, July 1999. ...



Google
Web
RFC-Ref