RFC 2881 (rfc2881) - Page 2 of 20
Network Access Server Requirements Next Generation (NASREQNG) NAS Model
Alternative Format: Original Text Document
RFC 2881 NASreq NAS Model July 2000
9.1 A Reference Model of a NAS .................................10
9.2 Terminology ................................................11
9.3 Analysis ...................................................13
9.3.1 Authentication and Security .............................13
9.3.2 Authorization and Policy ................................14
9.3.3 Accounting and Auditing .................................14
9.3.4 Resource Management .....................................14
9.3.5 Virtual Private Networks (VPN's) ........................14
9.3.6 Service Quality .........................................15
9.3.7 Roaming .................................................15
10. SECURITY CONSIDERATIONS......................................15
11. REFERENCES ..................................................16
12. ACKNOWLEDGMENTS..............................................17
13. AUTHORS' ADDRESSES ..........................................17
14. APPENDIX - ACRONYMS AND GLOSSARY:............................18
15. FULL COPYRIGHT STATEMENT.....................................20
1. Introduction
A Network Access Server is the initial entry point to a network for
the majority of users of network services. It is the first device in
the network to provide services to an end user, and acts as a gateway
for all further services. As such, its importance to users and
service providers alike is paramount. However, the concept of a
Network Access Server has grown up over the years without being
formally defined or analyzed [4].
1.1 Scope of this Document
There are several tradeoffs taken in this document. The purpose of
this document is to describe a model for evaluating NAS service
protocols. It will give examples of typical NAS hardware and
software features, but these are not to be taken as hard limitations
of the model, but merely illustrative of the points of discussion.
An important goal of the model is to offer a framework that allows
further development and expansion of capabilities in NAS
implementation.
As with most IETF projects, the focus is on standardizing the
protocol interaction between the components of the system. The
documents produced will not address the following areas:
- AAA server back-end implementation is abstracted and not
prescribed. The actual organization of the data in the server, its
internal interfaces, and capabilities are left to the
implementation.
Mitton & Beadles Informational