https://app.knowbase.one/vault/rfc/docid/6003
RFC5515: Layer 2 Tunneling Protocol (L2TP) Access Line Information Attribute Value Pair (AVP) Extensions
Network Working Group V. Mammoliti Request for Comments: 5515 C. Pignataro Category: Informational Cisco Systems P. Arberg ...
https://app.knowbase.one/vault/rfc/docid/6156
RFC5641: Layer 2 Tunneling Protocol Version 3 (L2TPv3) Extended Circuit Status Values
Network Working Group N. McGill Request for Comments: 5641 C. Pignataro Updates: 3931, 4349, 4454, 4591, 4719 Cisco Systems Category: Standards Track August 2009 ...