Ascend Tunnel Management Protocol - ATMP (RFC2107)
Original Publication Date: 1997-Feb-01
Included in the Prior Art Database: 2019-Feb-15
Internet Society Requests For Comment (RFCs)
This document specifies a generic tunnel management protocol that allows remote dial-in users to access their home network as if they were directly attached to the home network. This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind.
Network Working Group K. Hamzeh Request for Comments: 2107 Ascend Communications Category: Informational February 1997
Ascend Tunnel Management Protocol - ATMP
Status of this Memo
This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind. Distribution of this memo is unlimited.
This note documents a private protocol for tunnel management. This protocol is NOT the product of an IETF working group nor is it a standards track document. There is ongoing effort in an IETF working group which could result in a standards track document which specifies a protocol which provides similar functionality.
This document specifies a generic tunnel management protocol that allows remote dial-in users to access their home network as if they were directly attached to the home network. The user’s client software uses an address contained in the home network address space for the remote access. Packets to and from the home network are tunneled by the Network Access Server (NAS) to which the user connects and a Home Agent (HA) on the user’s home network. This allows for the support of access to Virtual Private Networks and also allows for the use of protocols other than IP to be carried over the tunnel. An example of how the RADIUS (Remote Authentication Dial In User Service) can be used to provide the necessary configuration information to support this service is also provided.
The Ascend Tunnel Management Protocol (ATMP) is a protocol currently being used in Ascend Communication products to allow dial-in client software to obtain virtual presence on a user’s home network from remote locations. A user calls into a remote NAS but, instead of using an address belonging to a network directly supported by the NAS, the client software uses an address belonging to the user’s "Home Network". This address can be either provided by the client software or assigned from a pool of addresses from the Home Network address space. In either case, this address belongs to the Home Network and therefore special routing considerations are required in
Hamzeh Informational [Page 1]
RFC 2107 ATMP February 1997
order to route packets to and from these clients. A tunnel between the NAS and a special "Home Agent" (HA) located on the Home Network is used to carry data to and from the client.
ATMP currently allows for both IP and IPX protocols to be tunneled between the NAS and the HA. The protocol to be used, the HA to use, and other user specific information is provided by some configuration mechanism that is beyond the scope of this document. Appendix A illustrates how RADIUS  is used to convey this information to the NAS.
The determination of the Home Network address to be used can be accomplished in different ways. It could, for example, be configured in the client and negotiated by IPCP (or IPXCP). Alternatively, it could be defined to be an address specific to the given user ID, or it...