Network Working Group B. Aboba, Microsoft

Network Working Group B. Aboba, Microsoft
Request for Comments: 2989 P. Calhoun, S. Glass, Sun Microsystems, Inc.
Category: Informational T. Hiller, P. McCann, H. Shiino, P. Walsh, Lucent
G. Zorn, G. Dommety, Cisco Systems, Inc.
C. Perkins, B. Patil, Nokia Telecommunications
D. Mitton, S. Manning, Nortel Networks
M. Beadles, SmartPipes Inc.
X. Chen, Alcatel
S. Sivalingham, Ericsson Wireless Communications
A. Hameed, Fujitsu
M. Munson, GTE Wireless
S. Jacobs, GTE Laboratories
B. Lim, LG Information & Communications, Ltd.
B. Hirschman, Motorola
R. Hsu, Qualcomm, Inc.
H. Koo, Samsung Telecommunications America, Inc.
M. Lipford, Sprint PCS
E. Campbell, 3Com Corporation
Y. Xu, Watercove Networks
S. Baba, Toshiba America Research, Inc.
E. Jaques, Vodaphone Airtouch
November 2000

Criteria for Evaluating AAA Protocols for Network Access

Status of this Memo

This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.

Copyright Notice

Copyright (C) The Internet Society (2000). All Rights Reserved.

Abstract

This document represents a summary of Authentication, Authorization,
Accounting (AAA) protocol requirements for network access. In
creating this document, inputs were taken from documents produced by
the Network Access Server Requirements Next Generation (NASREQ),
Roaming Operations (ROAMOPS), and MOBILEIP working groups, as well as
from TIA 45.6.

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RFC 2989 Network Access AAA Evaluation Criteria November 2000

This document summarizes the requirements collected from those
sources, separating requirements for authentication, authorization
and accounting. Details on the requirements are available in the
original documents.

1. Introduction

This document represents a summary of AAA protocol requirements for
network access. In creating this documents, inputs were taken from
documents produced by the NASREQ [3], ROAMOPS [2], and MOBILEIP [5]
working groups, as well as from TIA 45.6 [4]. This document
summarizes the requirements collected from those sources, separating
requirements for authentication, authorization and accounting.
Details on the requirements are available in the original documents.

1.1. Requirements language

In this document, the key words "MAY", "MUST, "MUST NOT", "optional",
"recommended", "SHOULD", and "SHOULD NOT", are to be interpreted as
described in [1].

Please note that the requirements specified in this document are to
be used in evaluating AAA protocol submissions. As such, the
requirements language refers to capabilities of these protocols; the
protocol documents will specify whether these features are required,
recommended, or optional. For example, requiring that a protocol
support confidentiality is NOT the same thing as requiring that all
protocol traffic be encrypted.

A protocol submission is not compliant if it fails to satisfy one or
more of the MUST or MUST NOT requirements for the capabilities that
it implements. A protocol submission that satisfies all the MUST,
MUST NOT, SHOULD and SHOULD NOT requirements for its capabilities is
said to be "unconditionally compliant"; one that satisfies all the
MUST and MUST NOT requirements but not all the SHOULD or SHOULD NOT
requirements for its protocols is said to be "conditionally
compliant."

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RFC 2989 Network Access AAA Evaluation Criteria November 2000

1.2. Terminology

Accounting
The act of collecting information on resource usage for the
purpose of trend analysis, auditing, billing, or cost
allocation.

Administrative Domain
An internet, or a collection of networks, computers, and
databases under a common administration. Computer entities
operating in a common administration may be assumed to
share administratively created security associations.

Attendant A node designed to provide the service interface between a
client and the local domain.

Authentication
The act of verifying a claimed identity, in the form of a
pre-existing label from a mutually known name space, as the
originator of a message (message authentication) or as the
end-point of a channel (entity authentication).

Authorization
The act of determining if a particular right, such as
access to some resource, can be granted to the presenter of
a particular credential.

Billing The act of preparing an invoice.

Broker A Broker is an entity that is in a different administrative
domain from both the home AAA server and the local ISP, and
which provides services, such as facilitating payments
between the local ISP and home administrative entities.
There are two different types of brokers; proxy and
routing.

Client A node wishing to obtain service from an attendant within
an administrative domain.

End-to-End
End-to-End is the security model that requires that
security information be able to traverse, and be validated
even when an AAA message is processed by intermediate nodes
such as proxies, brokers, etc.

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RFC 2989 Network Access AAA Evaluation Criteria November 2000

Foreign Domain
An administrative domain, visited by a Mobile IP client,
and containing the AAA infrastructure needed to carry out
the necessary operations enabling Mobile IP registrations.
From the point of view of the foreign agent, the foreign
domain is the local domain.

Home Domain
An administrative domain, containing the network whose
prefix matches that of a mobile node's home address, and
containing the AAA infrastructure needed to carry out the
necessary operations enabling Mobile IP registrations.
From the point of view of the home agent, the home domain
is the local domain.

Hop-by-hop
Hop-by-hop is the security model that requires that each
direct set of peers in a proxy network share a security
association, and the security information does not traverse
a AAA entity.

Inter-domain Accounting
Inter-domain accounting is the collection of information on
resource usage of an entity within an administrative
domain, for use within another administrative domain. In
inter-domain accounting, accounting packets and session
records will typically cross administrative boundaries.

Intra-domain Accounting
Intra-domain accounting is the collection of information on
resource within an administrative domain, for use within
that domain. In intra-domain accounting, accounting
packets and session records typically do not cross
administrative boundaries.

Local Domain
An administrative domain containing the AAA infrastructure
of immediate interest to a Mobile IP client when it is away
from home.

Proxy A AAA proxy is an entity that acts as both a client and a
server. When a request is received from a client, the
proxy acts as a AAA server. When the same request needs to
be forwarded to another AAA entity, the proxy acts as a AAA
client.

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Local Proxy
A Local Proxy is a AAA server that satisfies the definition
of a Proxy, and exists within the same administrative
domain as the network device (e.g., NAS) that issued the
AAA request. Typically, a local proxy will enforce local
policies prior to forwarding responses to the network
devices, and are generally used to multiplex AAA messages
from a large number of network devices.

Network Access Identifier
The Network Access Identifier (NAI) is the userID submitted
by the client during network access authentication. In
roaming, the purpose of the NAI is to identify the user as
well as to assist in the routing of the authentication
request. The NAI may not necessarily be the same as the
user's e-mail address or the user-ID submitted in an
application layer authentication.

Routing Broker
A Routing Broker is a AAA entity that satisfies the
definition of a Broker, but is NOT in the transmission path
of AAA messages between the local ISP and the home domain's
AAA servers. When a request is received by a Routing
Broker, information is returned to the AAA requester that
includes the information necessary for it to be able to
contact the Home AAA server directly. Certain
organizations providing Routing Broker services MAY also
act as a Certificate Authority, allowing the Routing Broker
to return the certificates necessary for the local ISP and
the home AAA servers to communicate securely.

Non-Proxy Broker
A Routing Broker is occasionally referred to as a Non-Proxy
Broker.

Proxy Broker
A Proxy Broker is a AAA entity that satisfies the
definition of a Broker, and acts as a Transparent Proxy by
acting as the forwarding agent for all AAA messages between
the local ISP and the home domain's AAA servers.

Real-time Accounting
Real-time accounting involves the processing of information
on resource usage within a defined time window. Time
constraints are typically imposed in order to limit
financial risk.

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RFC 2989 Network Access AAA Evaluation Criteria November 2000

Roaming Capability
Roaming capability can be loosely defined as the ability to
use any one of multiple Internet service providers (ISPs),
while maintaining a formal, customer-vendor relationship
with only one. Examples of cases where roaming capability
might be required include ISP "confederations" and ISP-
provided corporate network access support.

Session record
A session record represents a summary of the resource
consumption of a user over the entire session. Accounting
gateways creating the session record may do so by
processing interim accounting events.

Transparent Proxy
A Transparent Proxy is a AAA server that satisfies the
definition of a Proxy, but does not enforce any local
policies (meaning that it does not add, delete or modify
attributes or modify information within messages it
forwards).

2. Requirements Summary

The AAA protocol evaluation criteria for network access are
summarized below. For details on the requirements, please consult
the documents referenced in the footnotes.

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RFC 2989 Network Access AAA Evaluation Criteria November 2000

2.1. General requirements

These requirements apply to all aspects of AAA and thus are
considered general requirements.

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| General | NASREQ | ROAMOPS | MOBILE |
| Reqts. | | | IP |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Scalability | M | M | M |
| a | 12 | 3 | 30 39 |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Fail-over | M | | M |
| b | 12 | | 31 |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Mutual auth | M | | M |
| AAA client/server | 16 | | 30 |
| c | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Transmission level | | M | S |
| security | | 6 | 31 39 |
| d | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Data object | M | M | M |
| Confidentiality | 26 | 6 | 40 |
| e | | | |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Data object | M | M | M |
| Integrity | 16 | 6 | 31 39 |
| f | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Certificate transport | M | | S/M |
| g | 42 | |31,33/46 |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

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RFC 2989 Network Access AAA Evaluation Criteria November 2000

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Reliable AAA transport | M | | M |
| mechanism | 22 | | 31 32 |
| h | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Run Over IPv4 | M | M | M |
| | 11 | 1 | 33 |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Run Over IPv6 | M | | S |
| | 11 | 1 | 47 |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Support Proxy and | M | | M |
| Routing Brokers | 12 | | 31 39 |
| i | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Auditability | S | | |
| j | 25 | | |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Dual App and Transport | | O | M |
| Security not required | | 6 | 40 |
| k | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Ability to carry | M | | S |
| service-specific attr. | 43 | | 31 33 |
| l | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Key
M = MUST
S = SHOULD
O = MAY
N = MUST NOT
B = SHOULD NOT

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RFC 2989 Network Access AAA Evaluation Criteria November 2000

Clarifications

[a] The AAA protocol must be capable of supporting millions of users
and tens of thousands of simultaneous requests. The AAA
architecture and protocol MUST be capable of supporting tens of
thousands of devices, AAA servers, proxies and brokers.

[b] In the event of failure to communicate with a given server, the
protocol must provide a mechanism to change service to another
backup or secondary server.

[c] This requirement refers to the ability to support mutual
authentication between the AAA client and server.

[d] The AAA protocol requires authentication, integrity protection
and confidentiality at the transmission layer. This security
model is also referred to as hop-by-hop security, whereas the
security is established between two communicating peers. All of
the security is removed when the AAA message is processed by a
receiving AAA entity.

[e] The AAA protocol requires confidentiality at the object level,
where an object consists of one or more attributes. Object
level confidentiality implies that only the target AAA entity
for whom the data is ultimately destined may decrypt the data,
regardless of the fact that the message may traverse one or more
intermediate AAA entities (e.g., proxies, brokers).

[f] The AAA protocol requires authentication and integrity
protection at the object level, which consists of one or more
attributes. Object level authentication must be persistent
across one or more intermediate AAA entity (e.g., proxy, broker,
etc), meaning that any AAA entity in a proxy chain may verify
the authentication. This implies that data that is covered by
object level security CANNOT be modified by intermediate
servers.

[g] The AAA protocol MUST be capable of transporting certificates.
This requirement is intended as an optimization, in lieu of
requiring that an out-of-band protocol be used to fetch
certificates.

[h] This requirement refers to resilience against packet loss,
including:

1. Hop-by-hop retransmission and fail-over so that reliability
does not solely depend on single hop transport
retransmission.

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2. Control of the retransmission mechanism by the AAA
application.
3. Acknowledgment by the transport that a message was delivered
successfully, separate from message semantics or syntax
evaluation.
5. Piggy-backing of acknowledgments in AAA messages.
6. Timely delivery of AAA responses.

[i] In the Mobile IP AAA architecture, brokers can be in the
forwarding path, in which case they act as transparent proxies
(proxy brokers). Alternatively, it is also possible to conceive
of brokers operating as certifying authorities outside of the
forwarding path (routing brokers).

[j] An auditable process is one in which it is possible to
definitively determine what actions have been performed on AAA
packets as they travel from the home AAA server to the network
device and back.

[k] The AAA protocol MUST allow communication to be secured.
However, the AAA protocol MUST also allow an underlying security
service (e.g., IP Security) to be used. When the latter is
used, the former MUST NOT be required.

[l] The AAA protocol MUST be extensible by third parties (e.g.,
other IETF Working Groups), in order to define attributes that
are specific to the service being defined. This requirement
simply means that the AAA protocol MUST allow groups other than
the AAA WG to define standard attributes.

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RFC 2989 Network Access AAA Evaluation Criteria November 2000

2.2. Authentication Requirements

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Authentication | NASREQ | ROAMOPS | MOBILE |
| Reqts. | | | IP |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| NAI Support | M | M | S/M |
| a | 9 | 2 |32,34,39/|
| | | | 40 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| CHAP Support | M | M | |
| b | 10 | 3 | |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| EAP Support | M | S | |
| c | 10 | 3 | |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| PAP/Clear-Text Support | M | B | |
| d | 26 | 3 | |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Re-authentication | M | | S |
| on demand | 17 | | 33 |
| e | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Authorization Only | M | | |
| without Authentication | 9 | | |
| f | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Key
M = MUST
S = SHOULD
O = MAY
N = MUST NOT
B = SHOULD NOT

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RFC 2989 Network Access AAA Evaluation Criteria November 2000

Clarifications

[a] The AAA protocol MUST allow the use of Network Access
Identifiers (NAI) [8] to identify users and/or devices.

[b] The AAA protocol MUST allow CHAP [20] authentication information
to be transported. This is commonly used by Network Access
Servers that request authentication of a PPP user.

[c] The AAA protocol MUST allow for Extensible Authentication
Protocol (EAP) [14] payload to be transported. Since some EAP
authentication mechanisms require more than one round trip, the
AAA protocol must allow for such authentication mechanisms to be
used. The actual EAP authentication mechanism negotiated MUST
be transparent to the AAA protocol. When EAP is used,
authentication typically occurs between the user being
authenticated and his/her home AAA server.

[d] While PAP is deprecated, it is still in widespread use for its
original intended purpose, which is support of clear-text
passwords. As a result, a AAA protocol will need to be able to
securely transport clear-text passwords. This includes
providing for confidentiality of clear-text passwords traveling
over the wire, as well as protecting against disclosure of
clear-text passwords to proxies in the forwarding path.

[e] The AAA protocol MUST allow for a user to be re-authenticated
on-demand. The protocol MUST allow for this event to be
triggered by either the user, access device (AAA client), or the
home or visited AAA server.

[f] The AAA protocol MUST NOT require that credentials of the user
be provided during authorization. The AAA protocol supports
authorization by identification or assertion only.

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RFC 2989 Network Access AAA Evaluation Criteria November 2000

2.3. Authorization Requirements

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Authorization | NASREQ | ROAMOPS | MOBILE |
| Reqts. | | | IP |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Static and Dynamic | | | |
| IPv4/6 Address Assign. | M | M | M |
| a | 11 | 5 | 32 36 |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| RADIUS gateway | M | M | M |
| capability | 44 | 3 | 45 |
| b | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Reject | M | M | M |
| capability | 12 | 4 | 39 |
| c | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Precludes layer 2 | N | N | |
| tunneling | 11 | 5 | |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Re-Authorization on | M | | S |
| demand | 18 | | 30 33 |
| d | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Support for Access Rules,| M | | |
| Restrictions, Filters | 11, 19 | | |
| e | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| State Reconciliation | M | | |
| f | 20 | | |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Unsolicited Disconnect | M | | |
| g | 18 | | |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

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RFC 2989 Network Access AAA Evaluation Criteria November 2000

Key
M = MUST
S = SHOULD
O = MAY
N = MUST NOT
B = SHOULD NOT

Clarifications

[a] The AAA protocol MUST allow a server to provide a static or
dynamic address during the authorization phase of a user and/or
device. The address assigned MUST be either of type IPv4 or
IPv6. If both the client AND the server are aware of a pre-
configured address, then it is considered static. Anything else
is dynamic.

[b] This requirement refers to the ability of a new AAA protocol be
sufficiently compatible with the large installed base of
attributes for existing approaches (RADIUS), such that a server
implementation could speak both protocols, or translate between
them.

[c] This requirement refers to the ability of a proxy broker to deny
access without forwarding the access request to the AAA server,
or to deny access after receiving an access accept from the AAA
server.

[d] This requirement refers to the ability of the AAA client or
server to trigger re-authorization, or to the ability of the
server to send updated authorization information to the device,
such as "stop service." Authorization can allow for a time
period, then additional authorization can be sought to continue.
A server can initially authorize a user to connect and receive
services, but later decide the user is no longer allowed use of
the service, for example after N minutes. Authorizations can
have a time limit. Re-authorization does not necessarily imply
re-authentication.

[e] This requirement refers to the ability to of the protocol to
describe access operational limitations and authorization
restrictions to usage to the NAS which includes (but is not
limited to):

1. Session expirations and Idle Timeouts
2. Packet filters
3. Static routes
4. QoS parameters

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RFC 2989 Network Access AAA Evaluation Criteria November 2000

[f] This requirement refers to the ability of the NAS to use the AAA
server to manage resource allocation state. This capability can
assist with, but it is not synonymous with, simultaneous user
login control, port usage limitations, or IP address pooling.

The design must provide for recovery from data loss due to a
variety of faults, including NAS and AAA server reboots, and
NAS/AAA server communication outages, and MUST be independent of
the accounting stream. The granularity of the recovery of state
information after an outage may be on the order of a fraction of
a minute. In order to provide for state recovery, explicit
session/resource status and update and disconnect messages will
be required.

Because of potential multi-domain issues, only systems that
allocate or use a resource should track its state.

[g] This requirement refers to the ability of the AAA server to
request the NAS to disconnect an active session for
authorization policy reasons.

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RFC 2989 Network Access AAA Evaluation Criteria November 2000

2.4. Accounting Requirements

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Accounting | NASREQ | ROAMOPS | MOBILE |
| Reqts. | | | IP |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Real-time accounting | M | M | M |
| a | 14 | 7 | 31 |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Mandatory Compact | | M | |
| Encoding | | 7 | |
| b | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Accounting Record | | M | M |
| Extensibility | | 7 | 33 |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Batch Accounting | S | | |
| c | 21 | | |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Guaranteed Delivery | M | | M |
| d | 22 | | 31 |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Accounting Time Stamps | M | | M |
| e | 23 | | 40 |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Dynamic Accounting | M | | |
| f | 48 | | |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

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RFC 2989 Network Access AAA Evaluation Criteria November 2000

Key
M = MUST
S = SHOULD
O = MAY
N = MUST NOT
B = SHOULD NOT

Clarifications

[a] This requirement may be loosely defined as reporting
synchronously with events. Typically the time window is on the
order of seconds, not milliseconds.

[b] The AAA protocol's Accounting data format MUST NOT be bloated,
imposing a large overhead for one or more accounting data
elements.

[c] This requirement refers to the ability to buffer or store
multiple accounting records, and send them together at some
later time.

[d] This is an application layer acknowledgment. This is sent when
the receiving server is willing to take responsibility for the
message data.

[e] This requirement refers to the ability to reflect the time of
occurrence of events such as log-on, logoff, authentication,
authorization and interim accounting. It also implies the
ability to provide for unambiguous time-stamps.

[f] This requirement refers to the ability to account for dynamic
authentication and authorization. To support this, there can be
multiple accounting records for a single session.

2.5. Unique Mobile IP requirements

In addition to the above requirements, Mobile IP also has the
following additional requirements:

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RFC 2989 Network Access AAA Evaluation Criteria November 2000

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Encoding of Mobile IP | | | M |
| registration messages | | | 33 |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Firewall friendly | | | M |
| a | | | 35 |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | |
| Allocation of local Home | | | S/M |
| agent | | | 37/41 |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Key
M = MUST
S = SHOULD
O = MAY
N = MUST NOT
B = SHOULD NOT

Clarifications

[a] A firewall friendly protocol is one which is designed to
accommodate a firewall acting as a proxy. For example, this
would permit a Home Agent AAA server situated behind a firewall
to be reachable from the Internet for the purposes of providing
AAA services to a Mobile IP Foreign Agent.

Notes

[1] Section 4.2.1 of [2]
[2] Section 4.2.2 of [2]. Also see [8].
[3] Section 4.2.3 of [2]. Also see [14].
[4] Section 4.2.4 of [2].
[5] Section 4.2.5 of [2].
[6] Section 4.2.6 of [2].
[7] Section 4.3 of [2].
[8] Section 6 of [3]. Also see [6].
[9] Section 8.2.2.2 of [3]. Also see [14].
[10] Section 8.2.2.1 of [3]. Also see [14].
[11] Section 8.3.2.2 of [3]. Also see [7].
[12] Section 8.1.1 of [3].
[13] Section 8.1.4.4 of [3].
[14] Section 8.4.1.2 of [3].

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RFC 2989 Network Access AAA Evaluation Criteria November 2000

[15] Section 8.4.2 of [3].
[16] Section 8.1.3 of [3].
[17] Section 8.2.1.2 of [3].
[18] Section 8.3.1.1 of [3].
[19] Section 8.3.2.1 of [3]. Also see [7].
[20] Section 8.3.2.3 of [3]. Also see [6], [7].
[21] Section 8.4.1.3 of [3].
[22] Section 8.4.1.1 of [3].
[23] Section 8.4.1.4 of [3].
[24] Section 8.4.3.1 of [3].
[25] Section 8.4.3.2 of [3].
[26] Section 8.2.3.1 of [3].
[27] Section 8.3.3.1 of [3].
[28] Section 8.1.4.1 of [3].
[29] Refer [15]
[30] Section 3 of [5]
[31] Section 3.1 of [5]
[32] Section 4 of [5]
[33] Section 5 of [5]
[34] Section 5.1 of [5]
[35] Section 5.2 of [5]
[36] Section 5.3 of [5]
[37] Section 5.4 of [5]
[38] Section 5.5 of [5]
[39] Section 6 of [5]
[40] Section 5.1 of [4]
[41] Section 5.2.2 of [4]
[42] Section 8.2.2.2 of [3]
[43] Section 8.1.2.3 of [3]
[44] Section 8.1.2.2 of [3]
[45] Section 5.4 of [4]
[46] Section 7 of [4]
[47] Section 8 of [5]
[48] Section 8.4.1.5 of [3]

3. References

[1] Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119, March 1997.

[2] Aboba, B. and G. Zorn, "Criteria for Evaluating Roaming
Protocols", RFC 2477, January 1999.

[3] Beadles, M. and D. Mitton, "Criteria for Evaluating Network
Access Server Protocols", Work in Progress.

[4] Hiller, T., et al., "Cdma2000 Wireless Data Requirements for
AAA", Work in Progress.

Aboba, et al. Informational [Page 19]

RFC 2989 Network Access AAA Evaluation Criteria November 2000

[5] Glass, S., Hiller, T., Jacobs, S. and C. Perkins, "Mobile IP
Authentication, Authorization, and Accounting Requirements", RFC
2977, October 2000.

[6] Mitton, D., Beadles, M., "Network Access Server Requirements
Next Generation (NASREQNG) NAS Model", RFC 2881, July 2000.

[7] Mitton, D., "Network Access Server Requirements: Extended RADIUS
Practices", RFC 2882, July 2000.

[8] Aboba, B. and M. Beadles, "The Network Access Identifier", RFC
2486, January 1999.

[9] Rigney, C., Willens, S., Rubens, A. and W. Simpson, "Remote
Authentication Dial In User Service (RADIUS)", RFC 2865, June
2000.

[10] Rigney, C., "RADIUS Accounting", RFC 2866, June 2000.

[11] Simpson, W., Editor, "The Point-to-Point Protocol (PPP)", STD
51, RFC 1661, July 1994.

[12] Sklower, K., Lloyd, B., McGregor, G., Carr, D. and T. Coradetti,
"The PPP Multilink Protocol (MP)", RFC 1990, August 1996.

[13] Simpson, W., Editor, "PPP LCP Extensions", RFC 1570, January
1994.

[14] Blunk, L. and J. Vollbrecht, "PPP Extensible Authentication
Protocol (EAP)", RFC 2284, March 1998.

[15] Solomon, J. and S. Glass, "Mobile-IPv4 Configuration Option for
PPP IPCP", RFC 2290, Feb 1998

[16] Calhoun, P. and C. Perkins, "Mobile IP Network Access Identifier
Extension for IPv4", RFC 2794, March 2000.

[17] Perkins, C., "IP Mobility Support", RFC 2002, Oct 1996.

[18] Johnson, D. and C. Perkins, "Mobility Support in IPv6", Work in
Progress.

[19] Aboba, B. and J. Vollbrecht, "Proxy Chaining and Policy
Implementation in Roaming", RFC 2607, June 1999.

[20] Simpson, W., "PPP Challenge Handshake Authentication Protocol
(CHAP)", RFC 1994, August 1996.

Aboba, et al. Informational [Page 20]

RFC 2989 Network Access AAA Evaluation Criteria November 2000

4. Security Considerations

This document, being a requirements document, does not have any
security concerns. The security requirements on protocols to be
evaluated using this document are described in the referenced
documents.

5. IANA Considerations

This memo does not create any new number spaces for IANA
administration.

6. Acknowledgments

Thanks to the members of the Mobile IP, AAA, and NASREQ working
groups who have discussed and commented on these requirements. We
would also like to thank the members of the AAA evaluation team, Mike
St. Johns, Barney Wolf, Mark Stevens, David Nelson, Dave Mitton,
Basavaraj Patil and Stuart Barkley for their thorough review of this
document.

7. Authors' Addresses

Bernard Aboba
Microsoft Corporation
One Microsoft Way
Redmond, WA 98052

Phone: +1 425-936-6605
Fax: +1 425-936-7329
EMail: [email protected]

Pat R. Calhoun
Network and Security Research Center, Sun Labs
Sun Microsystems, Inc.
15 Network Circle
Menlo Park, CA 94025

Phone: +1 650-786-7733
EMail: [email protected]

Aboba, et al. Informational [Page 21]

RFC 2989 Network Access AAA Evaluation Criteria November 2000

Steven M. Glass
Sun Microsystems
1 Network Drive
Burlington, MA 01845

Phone: +1 781-442-0504
Fax: +1 781-442-1677
EMail: [email protected]

Tom Hiller
Wireless Data Standards & Architectures
Lucent Technologies
263 Shuman Drive
Room 1HP2F-218
Naperville, IL 60563

Phone: +1 630-976-7673
EMail: [email protected]

Peter J. McCann
Lucent Technologies
Rm 2Z-305
263 Shuman Blvd
Naperville, IL 60566

Phone: +1 630-713 9359
EMail: [email protected]

Hajime Shiino
Lucent Technologies Japan Ltd.
25 Mori Bldg. 1-4-30 Roppongi,
Minato-ku Tokyo
Japan

Phone: +81-3-5561-3695
EMail: [email protected]

Glen Zorn
Cisco Systems, Inc.
500 108th Avenue N.E., Suite 500
Bellevue, WA 98004

Phone: +1 425-468-0955
EMail: [email protected]

Aboba, et al. Informational [Page 22]

RFC 2989 Network Access AAA Evaluation Criteria November 2000

Gopal Dommety
IOS Network Protocols
Cisco Systems, Inc.
170 West Tasman Drive
San Jose, CA 95134-1706

Phone: +1 408-525-1404
Fax: +1 408-526-4952
EMail: [email protected]

Charles E. Perkins
Communications Systems Lab
Nokia Research Center
313 Fairchild Drive
Mountain View, CA

Phone: +1 650-625-2986
Fax: +1-650-625-2502
EMail: [email protected]

Basavaraj Patil
Nokia Networks
6000 Connection Dr.
Irving, TX 75039

Phone: +1 972-894-6709
Fax: +1 972-894-5349
EMail: [email protected]

David Mitton
Nortel Networks
880 Technology Park Drive
Billerica, MA 01821

Phone: +1 978-288-4570
EMail: [email protected]

Serge Manning
Nortel Networks
2201 Lakeside Blvd
Richardson, TX 75082-4399

Phone: +1 972-684-7277
EMail: [email protected]

Aboba, et al. Informational [Page 23]

RFC 2989 Network Access AAA Evaluation Criteria November 2000

Mark Anthony Beadles
SmartPipes, Inc.
565 Metro Place South
Suite 300
Dublin, OH 43017

Phone: +1 614-923-5657
EMail: [email protected]

Pat Walsh
Lucent Technologies
263 Shuman Blvd.
1F-545
Naperville, IL

Phone: +1 630-713-5063
EMail: [email protected]

Xing Chen
Alcatel USA
1000 Coit Road
Plano, TX 75075

Phone: +1 972-519-4142
Fax: +1 972-519-3300
EMail: [email protected]

Sanjeevan Sivalingham
Ericsson Wireless Communications Inc.,
Rm Q-356C
6455 Lusk Blvd
San Diego, CA 92126

Phone: +1 858-332-5670
EMail: [email protected]

Alan Hameed
Fujitsu
2801 Telecom Parkway
Richardson, TX 75082

Phone: +1 972-479-2089

Aboba, et al. Informational [Page 24]

RFC 2989 Network Access AAA Evaluation Criteria November 2000

Mark Munson
GTE Wireless
One GTE Place
Alpharetta, GA 30004

Phone: +1 678-339-4439
EMail: [email protected]

Stuart Jacobs
Secure Systems Department
GTE Laboratories
40 Sylvan Road,
Waltham, MA 02451-1128

Phone: +1 781-466-3076
Fax: +1 781-466-2838
EMail: [email protected]

Byung-Keun Lim
LG Electronics, Ltd.
533, Hogye-dong, Dongan-ku, Anyang-shi,
Kyungki-do,431-080
Korea

Phone: +82-31-450-7199
Fax: +82-31-450-7050
EMail: [email protected]

Brent Hirschman
1501 Shure Dr.
Arlington Hieghts, IL 60006

Phone: +1 847-632-1563
EMail: [email protected]

Raymond T. Hsu
Qualcomm Inc.
6455 Lusk Blvd.
San Diego, CA 92121

Phone: +1 619-651-3623
EMail: [email protected]

Aboba, et al. Informational [Page 25]

RFC 2989 Network Access AAA Evaluation Criteria November 2000

Haeng S. Koo
Samsung Telecommunications America, Inc.
1130 E. Arapaho Road
Richardson, TX 75081

Phone: +1 972-761-7755
EMail: [email protected]

Mark A. Lipford
Sprint PCS
8001 College Blvd.; Suite 210
Overland Park, KS 66210

Phone: +1 913-664-8335
EMail: [email protected]

Ed Campbell
3Com Corporation
1800 W. Central Rd.
Mount Prospect, IL 60056

Phone: +1 847-342-6769
EMail: [email protected]

Name: Yingchun Xu
WaterCove Networks
One Century Centre, Suite 550
1750 E. Golf Road
Schaumburg, IL

Phone: +1 847-477-9280
EMail: [email protected]

Shinichi Baba
Toshiba America Research, Inc.
PO Box 136,
Convent Station, NJ 07961-0136

Phone: +1 973-829-4795
EMail: [email protected]

Aboba, et al. Informational [Page 26]

RFC 2989 Network Access AAA Evaluation Criteria November 2000

Eric Jaques
Vodafone AirTouch
2999 Oak Road, MS-750
Walnut Creek, CA 94596

Phone: +1 925-279-6142
EMail: [email protected]

8. Intellectual Property Statement

The IETF takes no position regarding the validity or scope of any
intellectual property or other rights that might be claimed to
pertain to the implementation or use of the technology described in
this document or the extent to which any license under such rights
might or might not be available; neither does it represent that it
has made any effort to identify any such rights. Information on the
IETF's procedures with respect to rights in standards-track and
standards-related documentation can be found in BCP-11. Copies of
claims of rights made available for publication and any assurances of
licenses to be made available, or the result of an attempt made to
obtain a general license or permission for the use of such
proprietary rights by implementors or users of this specification can
be obtained from the IETF Secretariat.

The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
rights which may cover technology that may be required to practice
this standard. Please address the information to the IETF Executive
Director.

Aboba, et al. Informational [Page 27]

RFC 2989 Network Access AAA Evaluation Criteria November 2000

9. Full Copyright Statement

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.

Aboba, et al. Informational [Page 28]