RFC 2881
Network Access Server Requirements Next Generation (NASREQNG) NAS Model
Network Access Server Requirements Next Generation (NASREQNG) NAS Model ✨
RFC: 2881 🎀 Author(s): D. Mitton (Nortel Networks) and M. Beadles (SmartPipes Inc.) 💖 Stream: Network Working Group 🌸 Category: Informational 🧚 Date: July 2000 📅 Obsoletes / Updates: the title block doesn't list anything here 🦋
Status of This Memo 📜
okay so this memo is just information for the Internet community 💅 it does NOT count as an Internet standard of any kind, and you're free to distribute it as much as you want 🫶
Copyright Notice ©️
Copyright (C) The Internet Society (2000). All Rights Reserved. 🌈
Abstract 🦋
this doc describes the terminology and gives a model of a typical Network Access Server (NAS) 🫶 the whole point is to set the reference space for describing and evaluating NAS service protocols like RADIUS (RFCs 2865, 2866) [1], [2] and the follow-on work from the AAA Working Group 👑 plus the Diameter protocol [3] 🔥 all of these carry user service info for authentication, authorization, accounting, and auditing, between a NAS that wants to authenticate its incoming calls and a shared authentication server ✨
Table of Contents 📚
1. INTRODUCTION...................................................2
1.1 Scope of this Document ......................................2
1.2 Specific Terminology ........................................3
2. NETWORK ACCESS SYSTEM EQUIPMENT ASSUMPTIONS....................3
3. NAS SERVICES...................................................4
4. AUTHENTICATION, AUTHORIZATION AND ACCOUNTING (AAA) SERVERS.....5
5. TYPICAL NAS OPERATION SEQUENCE:................................5
5.1 Characteristics of Systems and Sessions: ....................6
5.2 Separation of NAS and AAA server functions ..................7
5.3 Network Management and Administrative features ..............7
6. AUTHENTICATION METHODS.........................................8
7. SESSION AUTHORIZATION INFORMATION..............................8
8. IP NETWORK INTERACTION.........................................9
9. A NAS MODEL...................................................10
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.....................................201. Introduction 🌷
a Network Access Server is the very first entry point into a network for most people using network services 💖 it's the first device to provide services to an end user, and it acts as the gateway for everything that comes after 🚪 so it's seriously paramount for users and service providers alike 👑 the thing is, the idea of a NAS grew up over the years without ever being formally defined or analyzed [4] 🙈
1.1. Scope of this Document 🧭
there are a few tradeoffs in this doc 💅 the purpose is to describe a model for evaluating NAS service protocols 🎀 it gives examples of typical NAS hardware and software features, but those aren't hard limits on the model, they're just illustrative for the discussion ✨ a big goal of the model is to offer a framework that lets NAS implementations keep growing and expanding their capabilities 🌈
as with most IETF projects, the focus is on standardizing the protocol interaction between the components of the system 🫶 the documents produced will NOT cover 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. 🧚
- NAS front-end call technology is not assumed to be static. Alternate and new technology will be accommodated. The resultant protocol specifications must be flexible in design to allow for new technologies and services to be added with minimal impact on existing implementations. 💜
1.2. Specific Terminology 📖
these terms are used in the doc the way described here 💅 a "Call" is the initiation of a network service request to the NAS 📞 that can mean a telephone call arriving over a dial-in or switched telephone network connection, or the creation of a tunnel to a tunnel server that becomes a virtual NAS 🦋 a "Session" is the NAS-provided service to a specific authorized user entity 👑
2. Network Access System Equipment Assumptions 🧚
a typical hardware-based NAS runs on a constrained system 🫠 it's important that NAS protocols don't assume unlimited resources on the platform 💖 these are the typical constraints:
- A computer system of minimal to moderate performance (example processors: Intel 386 or 486, Motorola 68000)
- A moderate amount, but not large RAM (typically varies with supported # of ports 1MB to 8MB)
- Some small amount of non-volatile memory, and/or way to be configured out-of-band
- No assumption of a local file system or disk storage
a NAS can be made up of a bunch of interconnected specialized processor system units 🔥 they're usually circuit boards (or blades) arrayed in a card cage (or chassis) and referred to by their position, i.e., slot number 🍓 the bus interconnection methods are typically proprietary and won't be addressed here 🙈
a NAS is sometimes called a Remote Access Server (RAS) because it typically allows remote access to a network 🌸 but a more general picture is an "Edge Server", where the NAS sits on the edge of an IP network of some type and allows dynamic access to it 🌈
these systems typically have:
- At least one LAN or high performance network interface (e.g., Ethernet, ATM, FR)
- At least one, but typically many, serial interface ports, which could be:
- serial RS232 ports direct wired or wired to a modem, or
- have integral hardware or software modems (V.22bis,V.32, V.34, X2, Kflex, V.90, etc.)
- have direct connections to telephone network digital WAN lines (ISDN, T1, T3, NFAS, or SS7)
- an aggregation of xDSL connections or PPPoe sessions [5] 💅
however, systems can do some of a NAS's functions without having these kinds of hardware characteristics 🦋 for example, an industry personal computer server system with several modem line connections 🖥️ those lines get managed like a dedicated NAS, but the system itself is a general file server 🫶 likewise, with the development of tunneling protocols (L2F [6], ATMP [7], L2TP [8]), tunnel server systems must behave like a "virtual" NAS 🎀 where the calls come from network tunneled sessions and not hardware ports ([11], [9], [10]) ✨
5. Typical NAS Operation Sequence ✨
okay so here's the typical NAS routine, bestie 💅 every time something connects, the NAS runs through this whole sequence:
- Call arrival on port or network 📞
- Port:
- auto-detect (or not) type of call
- CLI/SLIP: prompt for username and password (if security set)
- PPP: engage LCP, Authentication
- Request authentication from AAA server
- if okay, proceed to service
- may challenge
- may ask for password change/update
- Network:
- activate internal protocol server (telnet, ftp)
- engage protocol's authentication technique
- confirm authentication information with AAA server
- Port:
- Call Management Services 🔥
- Information from the telephone system or gateway controller arrives indicating that a call has been received
- The AAA server is consulted using the information supplied by the telephone system (typically Called or Calling number information)
- The server indicates whether to respond to the call by answering it, or by returning a busy to the caller.
- The server may also need to allocate a port to receive a call, and route it accordingly.
- Dial-out 📤
- packet destination matches outbound route pre-configured
- find profile information to setup call
- Request information from AAA server for call details
- VPN/Tunneling (compulsory) 🔐
- authentication server identifies user as remote
- tunnel protocol is invoked to a remote server
- authentication information may be forwarded to remote AAA server
- if successful, the local link is given a remote identity
- Multi-link aggregation 🧩
- after a new call is authenticated by the AAA server, if MP options are present, then other bundles with the same identifying information is searched for
- bundle searches are performed across multiple systems
- join calls that match authentication and originator identities as one network addressable data source with a single network IP address
- Hardwired (non-interactive) services 🖨️
- permanent WAN connections (Frame Relay or PSVCs)
- permanent serial connections (printers)
5.1 Characteristics of Systems and Sessions 🎀
so sessions must have a user identifier and authenticator to finish the authentication process, fr fr. Accounting starts from the time of call or service, though finer details are allowed. At the end of service, the call may be disconnected or allow re-authentication for additional services.
some systems let call handling decisions be made using telephone system info given before the call is answered (e.g., caller id or destination number). In those systems, calls may be busied-out or non-answered if system resources are not ready or available. not me being like "wait, the phone just gets rejected?" 🙈
authorization to run services is supplied and applied after authentication. A NAS may abort a call if session authorization information disagrees with call characteristics. Some system resources may be controlled by server driven policies. main character energy for the server, honestly 👑
accounting messages are sent to the accounting server when service begins, and ends, and possibly periodically during service delivery. Accounting is not necessarily a real-time service, the NAS may be queue and batch send event records. it's giving "batch it up and send it later" vibes 📦
5.2 Separation of NAS and AAA server functions 🧚
as a distributed system, the NAS and the Server have clearly separated roles, and it's so iconic 💜
- Server provides authentication services; checks passwords (static or dynamic)
- Server databases may be organized in any way (only protocol specified)
- Server may use external systems to authenticate (including OS user databases, token cards, one-time-lists, proxy or other means)
- Server provides authorization information to NAS
- The process of providing a service may lead to requests for additional information
- Service authorization may require real-time enforcement (services may be based on Time of Day, or variable cost debits)
- Session accounting information is tallied by the NAS and reported to server
5.3 Network Management and Administrative features 🌸
the NAS is presumed to have a method of configuration that lets it know its identity and network parameters at boot time. This configuration info is typically managed using the standard management protocols (e.g., SNMP). That includes the configuration of the parameters needed to contact the AAA server itself. The AAA server is not there to do network management for the NAS, though. Its job is to authorize and characterize the individual services for the users, so any feature that can be user specific is open to supply from the AAA server. ✨
the system may have other operational services used to run and control the NAS. Some users with Administrative privileges may get access to system configuration tools, or to services that affect the operation and configuration of the system (e.g., loading boot images, internal file system access, etc..). Access to these facilities may also be authenticated by the AAA server (provided it is configured and reachable!) and levels of access authorization may be provided. 🔒
6. Authentication Methods 🦋
a NAS typically supports a number of authentication systems. For async terminal users, these may be as simple as a prompt and input. For network datalink users, such as PPP, several different authentication methods will be supported (PAP, CHAP [12], MS-CHAP [13]). Some of these may actually be protocols in and of themselves (EAP [14] [15], and Kerberos). the vibes are so layered 🧁
also, the content of the authentication exchanges may not be straightforward. Hard token cards, such as the Safeword and SecurId, systems may generate one-time passphrases that must be validated against a proprietary server. In the case of multi-link support, it may be necessary to remember a session token or certificate for the later authentication of additional links. 🙃
in the cases of VPN and compulsory tunneling services, the user typically presents a Network Access Identifier (RFC 2486 [16]). This NAI is parsed into a destination network identifier either by the NAS or by the AAA server. The authentication information will typically not be validated locally, but by a AAA service at the remote end of the tunnel service. 🔐💖
7. Session Authorization Information 🌈
once a user has been authenticated, there are a bunch of individual bits of information that network management may want to configure and authorize for the given user or class of users. so much control, it's honestly iconic 👑
typical examples include:
- For async terminal users:
- banners
- custom prompts
- menus
- CLI macros - which could be used for: shortcuts, compound commands, restrictive scripts
- For network users:
- addresses, and routes
- callback instructions
- packet and activity filters
- network server addresses
- host server addresses
some services may need dynamic allocation of resources. Info about the resources required may not be known during the authentication phase, it may come up later. (e.g., IP Addresses for multi-link bundles) It's also possible that the authorization will change over the time of the session. To handle this, there has to be a division of responsibility between the NAS and the AAA server, or a cooperation using a stateful service. it's a whole teamwork moment 🫶
such services include:
- IP Address management
- Concurrent login limitations
- Tunnel usage limitations
- Real-time account expirations
- Call management policies
in the process of resolving resource information, it may be required that a certain level of service be supplied, and if it isn't available, the request is refused or corrective action is taken. no cap, that's a hard boundary 🚫
8. IP Network Interaction 🧚♀️
as the NAS participates in the IP network, it interacts with the routing mechanisms of the network itself. These interactions may also be controlled on a per-user/session basis. 🦋
for example, some input streams may be directed to specific hosts other than the default gateway for the destination subnet. To control services within the network provider's infrastructure, some types of packets may be discarded (filtered) before they enter the network. These filters could be applied based on examination of destination address and port number. Anti-spoofing packet controls may be applied to disallow traffic sourced from addresses other than what was assigned to the port. 🛡️
a NAS may also be an edge router system, and apply Quality of Service (QoS) policies to the packets. This makes it a QOS Policy Enforcement Point [19], [17]. It may learn QOS and other network policies for the user via the AAA service. 🎀
9. A NAS Model 💅
so far we've looked at examples of things that NASes do. The following attempts to define a NAS model that captures the fundamentals of NAS structure, so it's easier to categorize how it interacts with other network components. 🌸
a Network Access Server is a device which sits on the edge of a network, and provides access to services on that network in a controlled fashion, based on the identity of the user of the network services in question and on the policy of the provider of these services. For the purposes of this document, a Network Access Server is defined primarily as a device which accepts multiple point-to-point [18] links on one set of interfaces, providing access to a routed network or networks on another set of interfaces. 🔥
Note that there are many things that a Network Access Server is not. A NAS is not simply a router, although it will typically include routing functionality in it's interface to the network. A NAS is not necessarily a dial access server, although dial access is one common means of network access, and brings its own particular set of requirements to NAS's.
a NAS is the first device in the IP network to provide services to an end user, and acts as a gateway for all further services. It is the point at which users are authenticated, access policy is enforced, network services are authorized, network usage is audited, and resource consumption is tracked. That is, a NAS often acts as the policy enforcement point for network AAAA (authentication, authorization, accounting, and auditing) services. A NAS is typically the first place in a network where security measures and policy may be implemented. the gatekeeper era is real 🚪✨
9.1 A Reference Model of a NAS 🧠✨
okay bestie, before we dive in, here's a picture of a NAS, the stuff it depends on, and the interfaces it uses. It's an abstraction, a reference model, not a blueprint for any one real NAS 💅
Users
v v v v v v v
| | PSTN | |
| | or | |
|encapsulated
+-----------------+
| (Modems) |
+-----------------+
| | | | | | |
+--+----------------------------+
| | |
|N | Client Interface |
| | |
|A +----------Routing ----------+
| | |
|S | Network Interface |
| | |
+--+----------------------------+
/ | \
/ | \
/ | \
/ | \
POLICY MANAGEMENT/ | \ DEVICE MANAGEMENT
+---------------+ | +-------------------+
| Authentication| _/^\_ |Device Provisioning|
+---------------+ _/ \_ +-------------------+
| Authorization | _/ \_ |Device Monitoring |
+---------------+ _/ \_ +-------------------+
| Accounting | / The \
+---------------+ \_ Network(s) _/
| Auditing | \_ _/
+---------------+ \_ _/
\_ _/
\_/9.2 Terminology 📚💖
Here's the rundown on all the moving parts in that diagram 🦋
Client Interfaces - A NAS can have one or more client interfaces, and these are where end users show up asking for network access. Users can hook in through modems over a PSTN, or through tunnels over a data network 🎀 There are two broad classes of NAS, depending on what kind of incoming client interface it has. One NAS device can be in both classes at once, so don't be surprised 🌈
Dial Access Servers - A Dial Access Server is a NAS whose client interfaces are modems, local or remote, attached to a PSTN 📞
Tunnel Servers - A Tunnel Server is a NAS whose client interfaces are tunneling endpoints in a protocol like L2TP 🚇
Network Interfaces - A NAS can have one or more network interfaces, and they're the connections to the networks where access is being granted 🌐
Routing - If the network you're getting access to is a routed network, a NAS will usually come with routing functionality built in 🗺️
Policy Management Interface - This is how a NAS lets you manage access to network services on a per-user basis. It could be a configuration file, a GUI, an API, or a protocol like RADIUS, Diameter, or COPS [19]. It gives you granular resource management and policy enforcement, which is so iconic 👑
Authentication - This is confirming that a user asking for services really is a valid user of the network services they asked for. It happens when someone shows an identity and credentials. Examples of credentials are passwords, one-time tokens, digital certificates, and phone numbers (calling or called) 🔐
Authorization - This is deciding what kind of service a user gets, including "no service," based on how they authenticated, what they're asking for, and the current system state 💅 It can come with restrictions, like time-of-day limits, physical location limits, or limits on logging in more than once as the same user. Authorization decides what the granted service actually looks like. Types of service include, but aren't limited to: IP address filtering, address assignment, route assignment, QoS/differential services, bandwidth control/traffic management, compulsory tunneling to a specific endpoint, and encryption 🎀
Accounting - This is keeping track of how much of the NAS's resources users consume. The info can be used for management, planning, billing, or other stuff 🧾 Real-time accounting is info delivered at the same time the resources are being used. Batch accounting is info that gets saved and delivered later. The usual stuff gathered is who the user is, what service they got, when it started, and when it ended ⏰
Auditing - This is tracking what users are doing. Accounting is about how much they consume, but auditing is about figuring out the nature of a user's network activity 🕵️♀️ Examples are the user's identity, the services they used, what hosts they accessed and when, which protocols they used, and so on 🫶
AAAA Server - An AAAA Server is a server, or a set of servers, that provides authentication, authorization, accounting, and auditing services 🏰 These can live right on the NAS, but more commonly they're on a separate server and talk to the NAS's User Management Interface over an AAAA protocol. All four AAAA functions can sit on one server, or be split up across several 🧩
Device Management Interface - A NAS is a network device owned, operated, and managed by some entity, and this interface is how that entity runs and manages the NAS. It could be a configuration file, a GUI, an API, or a protocol like SNMP [20] ⚙️
Device Monitoring - This is keeping an eye on the status, activity, and usage of the NAS as a network device 👀
Device Provisioning - This is the configurations, settings, and control of the NAS as a network device 🛠️
9.3 Analysis 🔍🌸
okay, now let's see what a NAS actually does with that reference model 💖
9.3.1 Authentication and Security 🛡️
NAS's are the first stop for checking who network users are, and they keep user sessions secure 🔒 This is usually done by checking credentials like a PPP PAP user name/password pair or a PPP CHAP user name and challenge/response. It can also be extended to authentication via telephone number info, digital certificates, or biometrics 🧬 NAS's can also authenticate themselves to users, which is a whole vibe 🤝 Since lots of different administrative entities might share one NAS, the authentication might actually happen through a back-end proxy, a referral, or a brokering process 🔁
On top of protecting users, NAS's can be secured devices too. That can include secure ways of managing and monitoring them, using IP Security [21], and even taking part in a Public Key Infrastructure 🔑
9.3.2 Authorization and Policy 📜
NAS's are the first point of authorization for using network resources, and they act as policy enforcement points for the services they hand out to users 👑 They can provision those services in a statically or dynamically configured way ⚡ A NAS can also manage resources by granting specific types of service based on the current network state 📊 When it's operated in a shared way, the NAS policy might be decided based on the policies of multiple end systems 🤝
9.3.3 Accounting and Auditing 📒
Since NAS services are consumable resources, usage info often has to be collected for soft policy management, reporting, planning, and accounting 🧾 A dynamic, real-time view of NAS usage is often needed for network auditing 👀 And since a NAS can be shared among multiple administrative entities, usage info often has to be delivered to multiple endpoints 📬 Accounting is done with protocols like RADIUS [2] 💌
9.3.4 Resource Management 🎁
NAS's hand out resources to users, and they're often doing it dynamically 🌟 Examples of the stuff NAS's dole out are IP addresses, network names and name server identities, tunnels, and PSTN resources like phone lines and numbers 📞 Also, NAS's might run in an outsourcing model, where multiple entities are competing for the same resources. Drama! 😭
9.3.5 Virtual Private Networks (VPN's) 🔐
NAS's often take part in VPN's, and they can be how VPN's actually get implemented 🌈 Examples of NAS's in VPN's are: Dial Access Servers that build compulsory tunnels, Dial Access Servers that provide services to voluntary tunnelers, and Tunnel Servers that provide tunnel termination services 🚇 A NAS can offer VPN and public network services at the same time to different users, depending on policy and user identity 🦋
9.3.6 Service Quality ✨
A NAS can deliver different qualities, types, or levels of service to different users, based on policy and identity 💎 It can handle bandwidth management, allow differential speeds or methods of access, or even take part in provisioned or signaled Quality of Service (QoS) networks 🚀
9.3.7 Roaming 🧳
NAS's are often run in a shared or outsourced way, or a NAS operator can make agreements with other service providers to let users from those providers get access (roaming operations) 🌍 NAS's are often part of a global network too. All of this means a NAS often serves users from multiple administrative domains at the same time 💜 So the features of NAS's may be driven by roaming requirements [22] 🫶
10. Security Considerations 🚨💀
This document describes a model, not a particular solution. 🙈
As mentioned in section 9.3.1 and elsewhere, NAS'es care a lot about the security of several parts of how they operate, including:
- Providing sufficiently robust authentication techniques as required by network policies,
- NAS authentication of configured authentication server(s),
- Server ability to authenticate configured clients,
- Hiding of the authentication information from network snooping to protect from attacks and provide user privacy,
- Protecting the integrity of message exchanges from attacks such as replay or man-in-the-middle,
- Inability of other hosts to interfere with services authorized to NAS, or gain unauthorized services,
- Inability of other hosts to probe or guess at authentication information,
- Protection of NAS system configuration and administration from unauthorized users,
- Protection of the network from illegal packets sourced by accessing connections.
11. References 📚
Okay bestie, here's the reading list. Every single source is listed with all its details, no cap 🫶
[1] Rigney, C., Willens, S., Rubens, A. and W. Simpson, "Remote Authentication Dial In User Service (RADIUS)", RFC 2865, June 2000.
[2] Rigney, C., "RADIUS Accounting", RFC 2866, June 2000.
[3] Calhoun, P., "Diameter Base Protocol", Work in Progress.
[4] Zorn, G., "Yet Another Authentication Protocol (YAAP)", Work in Progress.
[5] Mamakos, L., Lidl, K., Evarts, K., Carrel, D., Simone, D. and R. Wheeler, "A Method for Transmitting PPP Over Ethernet (PPPoE)", RFC 2516, February 1999.
[6] Valencia, A., Littlewood, M. and T. Kolar, "Cisco Layer Two Forwarding (Protocol) L2F", RFC 2341, May 1998.
[7] Hamzeh, K., "Ascend Tunnel Management Protocol - ATMP", RFC 2107, February 1997.
[8] Valencia, A., Townsley, W., Rubens, A., Pall, G., Zorn, G., and B. Palter, "Layer Two Tunneling Protocol (L2TP)", RFC 2661, August 1999.
[9] Zorn, G., Leifer, D., Rubens, A., Shriver, J. and M. Holdrege, "RADIUS Attributes for Tunnel Protocol Support", RFC 2868, June 2000.
[10] Zorn, G., Aboba, B. and D. Mitton, "RADIUS Accounting Modifications for Tunnel Protocol Support", RFC 2867, June 2000.
[11] Aboba, B. and G. Zorn, "Implementation of PPTP/L2TP Compulsory Tunneling via RADIUS", RFC 2809, April 2000.
[12] Simpson, W., "PPP Challenge Handshake Authentication Protocol (CHAP)", RFC 1994, August 1996.
[13] Zorn, G. and S. Cobb, "Microsoft PPP CHAP Extensions", RFC 2433, March 1998.
[14] Blunk, L. and J. Vollbrecht, "PPP Extensible Authentication Protocol (EAP)", RFC 2284, March 1998.
[15] Calhoun, et al., "Extensible Authentication Protocol Support in RADIUS", Work in Progress.
[16] Aboba, B. and M. Beadles, "The Network Access Identifier", RFC 2486, January 1999.
[17] Braden, R., Zhang, L., Berson, S., Herzog, S. and S. Jamin, "Resource ReSerVation Protocol (RSVP) Version 1 Functional Specification", RFC 2205, September 1997.
[18] Simpson, W., Editor, "The Point-to-Point Protocol (PPP)", STD 51, RFC 1661, July 1994.
[19] Boyle, J., Cohen, R., Durham, D., Herzog, S., Raja, R. and A. Sastry. "The COPS (Common Open Policy Service) Protocol", RFC 2748, January 2000.
[20] Case, J., Fedor, M., Schoffstall, M. and J. Davin. "A Simple Network Management Protocol (SNMP)", STD 15, RFC 1157, May 1990.
[21] Atkinson, R. and S. Kent, "Security Architecture for the Internet Protocol", RFC 2401, November 1998.
[22] Aboba, Zorn, "Dialup Roaming Requirements", Work in Progress.
12. Acknowledgments 🌸
Huge shoutout to the people who made this doc happen 🫶 This document is a synthesis of my earlier draft and Mark Beadles' NAS Reference Model draft. Two drafts, one slay-worthy doc ✨
13. Authors' Addresses 💌
Here's how to reach the authors, bestie 🦋
David Mitton
Nortel Networks
880 Technology Park Drive
Billerica, MA 01821
Phone: 978-288-4570
EMail: dmitton@nortelnetworks.com
Mark Beadles
SmartPipes Inc.
545 Metro Place South
Suite 100
Dublin, OH 43017
Phone: 614-327-8046
EMail: mbeadles@smartpipes.com14. Appendix - Acronyms and Glossary 🧚
Okay this is the cheat sheet, and I am obsessed with how many acronyms are in this doc 💀 Every term is here, word for word.
- AAA - Authentication, Authorization, Accounting, The three primary services required by a NAS server or protocol.
- NAS - Network Access Server, a system that provides access to a network. In some cases also know as a RAS, Remote Access Server.
- CLI - Command Line Interface, an interface to a command line service for use with an common asynchronous terminal facility.
- SLIP - Serial Line Internet Protocol, an IP-only serial datalink, predecessor to PPP.
- PPP - Point-to-Point Protocol; a serial datalink level protocol that supports IP as well as other network protocols. PPP has three major states of operation: LCP - Link layer Control Protocol, Authentication, of which there are several types (PAP, CHAP, EAP), and NCP - Network layer Control Protocol, which negotiates the network layer parameters for each of the protocols in use.
- IPX - Novell's NetWare transport protocol
- NETBEUI - A Microsoft/IBM LAN protocol used by Microsoft file services and the NETBIOS applications programming interface.
- ARAP - AppleTalk Remote Access Protocol
- LAT - Local Area Transport; a Digital Equipment Corp. LAN protocol for terminal services.
- PPPoe - PPP over Ethernet; a protocol that forwards PPP frames on an LAN infrastructure. Often used to aggregate PPP streams at a common server bank.
- VPN - Virtual Private Network; a term for networks that appear to be private to the user by the use of tunneling techniques.
- FR - Frame Relay, a synchronous WAN protocol and telephone network intraconnect service.
- PSVC - Permanent Switched Virtual Circuit - a service which delivers an virtual permanent circuit by a switched network.
- PSTN - Public Switched Telephone Network
- ISDN - Integrated Services Digital Network, a telephone network facility for transmitting digital and analog information over a digital network connection. A NAS may have the ability to receive the information from the telephone network in digital form.
- ISP - Internet Service Provider; a provider of Internet access (also Network Service Provider, NSP).
- BRI - Basic Rate Interface; a digital telephone interface.
- PRI - Primary Rate Interface; a digital telephone interface of 64K bits per second.
- T1 - A digital telephone interface which provides 24-36 channels of PRI data and one control channel (2.048 Mbps).
- T3 - A digital telephone interface which provides 28 T1 services. Signalling control for the entire connection is provided on a dedicated in-band channel.
- NFAS - Non-Facility Associated Signaling, a telephone network protocol/service for providing call information on a separate wire connection from the call itself. Used with multiple T1 or T3 connections.
- SS7 - A telephone network protocol for communicating call supervision information on a separate data network from the voice network.
- POP - Point Of Presence; a geographic location of equipment and interconnection to the network. An ISP typically manages all equipment in a single POP in a similar manner.
- VSA - Vendor Specific Attributes; RADIUS attributes defined by vendors using the provision of attribute 26.
15. Full Copyright Statement ⚖️
Last but not least, the legal stuff. It's not the fun part, but you still gotta read it, periodt 💅 The wording below is kept exactly as written, because this notice can't be changed.
Copyright (C) The Internet Society (2000). All Rights Reserved.
This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of developing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into languages other than English.
The limited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Acknowledgement 🌈
Funding for the RFC Editor function is currently provided by the Internet Society. Thank you to them, and thank you for reading all the way to the end, bestie 🥹💜
📦 where this page comes from
- ietf: rfc2881 2000-07
- 💖 girlified by claude-haiku-5-5 on : a language model's rewrite of the original, under its terms