rfc3310.Hypertext Transfer Protocol (HTTP) Digest Authentication Usin-USB迷|专注于互联网分享

2024年9月29日发(作者：哀安翔)

Network Working Group A. Niemi

Request for Comments: 3310 Nokia

Category: Informational J. Arkko

V. Torvinen

Ericsson

September 2002

Hypertext Transfer Protocol (HTTP) Digest Authentication

Using Authentication and Key Agreement (AKA)

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.

Abstract

This memo specifies an Authentication and Key Agreement (AKA) based

one-time password generation mechanism for Hypertext Transfer

Protocol (HTTP) Digest access authentication. The HTTP

Authentication Framework includes two authentication schemes: Basic

and Digest. Both schemes employ a shared secret based mechanism for

access authentication. The AKA mechanism performs user

authentication and session key distribution in Universal Mobile

Telecommunications System (UMTS) networks. AKA is a challenge-

response based mechanism that uses symmetric cryptography.

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RFC 3310 HTTP Digest Authentication Using AKA September 2002

Table of Contents

1. Introduction and Motivation . . . . . . . . . . . . . . . . . 2

1.1 Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.2 Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 4

2. AKA Mechanism Overview . . . . . . . . . . . . . . . . . . . . 4

3. Specification of Digest AKA . . . . . . . . . . . . . . . . . 5

3.1 Algorithm Directive . . . . . . . . . . . . . . . . . . . . . 5

3.2 Creating a Challenge . . . . . . . . . . . . . . . . . . . . . 6

3.3 Client Authentication . . . . . . . . . . . . . . . . . . . . 7

3.4 Synchronization Failure . . . . . . . . . . . . . . . . . . . 7

3.5 Server Authentication . . . . . . . . . . . . . . . . . . . . 8

4. Example Digest AKA Operation . . . . . . . . . . . . . . . . . 8

5. Security Considerations . . . . . . . . . . . . . . . . . . . 12

5.1 Authentication of Clients using Digest AKA . . . . . . . . . . 13

5.2 Limited Use of Nonce Values . . . . . . . . . . . . . . . . . 13

5.3 Multiple Authentication Schemes and Algorithms . . . . . . . . 14

5.4 Online Dictionary Attacks . . . . . . . . . . . . . . . . . . 14

5.5 Session Protection . . . . . . . . . . . . . . . . . . . . . . 14

5.6 Replay Protection . . . . . . . . . . . . . . . . . . . . . . 15

5.7 Improvements to AKA Security . . . . . . . . . . . . . . . . . 15

6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15

6.1 Registration Template . . . . . . . . . . . . . . . . . . . . 16

Normative References . . . . . . . . . . . . . . . . . . . . . 16

Informative References . . . . . . . . . . . . . . . . . . . . 16

A. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 17

Authors’ Addresses . . . . . . . . . . . . . . . . . . . . . . 17

Full Copyright Statement . . . . . . . . . . . . . . . . . . . 18

1. Introduction and Motivation

The Hypertext Transfer Protocol (HTTP) Authentication Framework,

described in RFC 2617 [2], includes two authentication schemes: Basic

and Digest. Both schemes employ a shared secret based mechanism for

access authentication. The Basic scheme is inherently insecure in

that it transmits user credentials in plain text. The Digest scheme

improves security by hiding user credentials with cryptographic

hashes, and additionally by providing limited message integrity.

The Authentication and Key Agreement (AKA) [6] mechanism performs

authentication and session key distribution in Universal Mobile

Telecommunications System (UMTS) networks. AKA is a challenge-

response based mechanism that uses symmetric cryptography. AKA is

typically run in a UMTS IM Services Identity Module (ISIM), which

resides on a smart card like device that also provides tamper

resistant storage of shared secrets.

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This document specifies a mapping of AKA parameters onto HTTP Digest

authentication. In essence, this mapping enables the usage of AKA as

a one-time password generation mechanism for Digest authentication.

As the Session Initiation Protocol (SIP) [3] Authentication Framework

closely follows the HTTP Authentication Framework, Digest AKA is

directly applicable to SIP as well as any other embodiment of HTTP

Digest.

1.1 Terminology

This chapter explains the terminology used in this document.

AKA

Authentication and Key Agreement.

AuC

Authentication Center. The network element in mobile networks

that can authorize users either in GSM or in UMTS networks.

AUTN

Authentication Token. A 128 bit value generated by the AuC, which

together with the RAND parameter authenticates the server to the

client.

AUTS

Authentication Token. A 112 bit value generated by the client

upon experiencing an SQN synchronization failure.

Cipher Key. An AKA session key for encryption.

Integrity Key. An AKA session key for integrity check.

ISIM

IP Multimedia Services Identity Module.

Personal Identification Number. Commonly assigned passcodes for

use with automatic cash machines, smart cards, etc.

RAND

Random Challenge. Generated by the AuC using the SQN.

RES

Authentication Response. Generated by the ISIM.

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SIM

Subscriber Identity Module. GSM counter part for ISIM.

SQN

Sequence Number. Both AuC and ISIM maintain the value of the SQN.

UMTS

Universal Mobile Telecommunications System.

XRES

Expected Authentication Response. In a successful authentication

this is equal to RES.

1.2 Conventions

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",

"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this

document are to be interpreted as described in BCP 14, RFC 2119 [1].

2. AKA Mechanism Overview

This chapter describes the AKA operation in detail:

1. A shared secret K is established beforehand between the ISIM and

the Authentication Center (AuC). The secret is stored in the

ISIM, which resides on a smart card like, tamper resistant device.

2. The AuC of the home network produces an authentication vector AV,

based on the shared secret K and a sequence number SQN. The

authentication vector contains a random challenge RAND, network

authentication token AUTN, expected authentication result XRES, a

session key for integrity check IK, and a session key for

encryption CK.

3. The authentication vector is downloaded to a server. Optionally,

the server can also download a batch of AVs, containing more than

one authentication vector.

4. The server creates an authentication request, which contains the

random challenge RAND, and the network authenticator token AUTN.

5. The authentication request is delivered to the client.

6. Using the shared secret K and the sequence number SQN, the client

verifies the AUTN with the ISIM. If the verification is

successful, the network has been authenticated. The client then

produces an authentication response RES, using the shared secret K

and the random challenge RAND.

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RFC 3310 HTTP Digest Authentication Using AKA September 2002

7. The authentication response, RES, is delivered to the server.

8. The server compares the authentication response RES with the

expected response, XRES. If the two match, the user has been

successfully authenticated, and the session keys, IK and CK, can

be used for protecting further communications between the client

and the server.

When verifying the AUTN, the client may detect that the sequence

numbers between the client and the server have fallen out of sync.

In this case, the client produces a synchronization parameter AUTS,

using the shared secret K and the client sequence number SQN. The

AUTS parameter is delivered to the network in the authentication

response, and the authentication can be tried again based on

authentication vectors generated with the synchronized sequence

number.

For a specification of the AKA mechanism and the generation of the

cryptographic parameters AUTN, RES, IK, CK, and AUTS, see reference

3GPP TS 33.102 [6].

3. Specification of Digest AKA

In general, the Digest AKA operation is identical to the Digest

operation in RFC 2617 [2]. This chapter specifies the parts in which

Digest AKA extends the Digest operation. The notation used in the

Augmented BNF definitions for the new and modified syntax elements in

this section is as used in SIP [3], and any elements not defined in

this section are as defined in SIP and the documents to which it

refers.

3.1 Algorithm Directive

In order to direct the client into using AKA for authentication

instead of the standard password system, the RFC 2617 defined

algorithm directive is overloaded in Digest AKA:

algorithm = "algorithm" EQUAL ( aka-namespace

/ algorithm-value )

aka-namespace = aka-version "-" algorithm-value

aka-version = "AKAv" 1*DIGIT

algorithm-value = ( "MD5" / "MD5-sess" / token )

algorithm

A string indicating the algorithm used in producing the digest and

the checksum. If the directive is not understood, the nonce

SHOULD be ignored, and another challenge (if one is present)

should be used instead. The default aka-version is "AKAv1".

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Further AKA versions can be specified, with version numbers

assigned by IANA [7]. When the algorithm directive is not

present, it is assumed to be "MD5". This indicates, that AKA is

not used to produce the Digest password.

Example:

algorithm=AKAv1-MD5

If the entropy of the used RES value is limited (e.g., only 32

bits), reuse of the same RES value in authenticating subsequent

requests and responses is NOT RECOMMENDED. Such a RES value

SHOULD only be used as a one-time password, and algorithms such as

"MD5-sess", which limit the amount of material hashed with a

single key, by producing a session key for authentication, SHOULD

NOT be used.

3.2 Creating a Challenge

In order to deliver the AKA authentication challenge to the client in

Digest AKA, the nonce directive defined in RFC 2617 is extended:

nonce = "nonce" EQUAL ( aka-nonce

/ nonce-value )

aka-nonce = LDQUOT aka-nonce-value RDQUOT

aka-nonce-value =

server specific data>

nonce

A parameter, which is populated with the Base64 [4] encoding of

the concatenation of the AKA authentication challenge RAND, the

AKA AUTN token, and optionally some server specific data, as in

Figure 1.

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Example:

nonce="MzQ0a2xrbGtmbGtsZm9wb2tsc2tqaHJzZXNy9uQyMzMzMzQK="

0 1 2 3

0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

| |

| RAND |

| |

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

| |

| AUTN |

| |

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

+-+-+-+-+-+-+-+-+-+-+-+

Figure 1: Generating the nonce value.

If the server receives a client authentication containing the "auts"

parameter defined in Section 3.4, that includes a valid AKA AUTS

parameter, the server MUST use it to generate a new challenge to the

client. Note that when the AUTS is present, the included "response"

parameter is calculated using an empty password (password of ""),

instead of a RES.

3.3 Client Authentication

When a client receives a Digest AKA authentication challenge, it

extracts the RAND and AUTN from the "nonce" parameter, and assesses

the AUTN token provided by the server. If the client successfully

authenticates the server with the AUTN, and determines that the SQN

used in generating the challenge is within expected range, the AKA

algorithms are run with the RAND challenge and shared secret K.

The resulting AKA RES parameter is treated as a "password" when

calculating the response directive of RFC 2617.

3.4 Synchronization Failure

For indicating an AKA sequence number synchronization failure, and to

re-synchronize the SQN in the AuC using the AUTS token, a new

directive is defined for the "digest-response" of the "Authorization"

request header defined in RFC 2617:

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RFC 3310 HTTP Digest Authentication Using AKA September 2002

auts = "auts" EQUAL auts-param

auts-param = LDQUOT auts-value RDQUOT

auts-value =

auts

A string carrying a base64 encoded AKA AUTS parameter. This

directive is used to re-synchronize the server side SQN. If the

directive is present, the client doesn’t use any password when

calculating its credentials. Instead, the client MUST calculate

its credentials using an empty password (password of "").

Example:

auts="CjkyMzRfOiwg5CfkJ2UK="

Upon receiving the "auts" parameter, the server will check the

validity of the parameter value using the shared secret K. A valid

AUTS parameter is used to re-synchronize the SQN in the AuC. The

synchronized SQN is then used to generate a fresh authentication

vector AV, with which the client is then re-challenged.

3.5 Server Authentication

Even though AKA provides inherent mutual authentication with the AKA

AUTN token, mutual authentication mechanisms provided by Digest may

still be useful in order to provide message integrity.

In Digest AKA, the server uses the AKA XRES parameter as "password"

when calculating the "response-auth" of the "Authentication-Info"

header defined in RFC 2617.

4. Example Digest AKA Operation

Figure 2 below describes a message flow describing a Digest AKA

process of authenticating a SIP request, namely the SIP REGISTER

request.

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RFC 3310 HTTP Digest Authentication Using AKA September 2002

Client Server

| 1) REGISTER |

|------------------------------------------------------>|

| |

| +-----------------------------+

| | Server runs AKA algorithms, |

| | generates RAND and AUTN. |

| +-----------------------------+

| |

| 2) 401 Unauthorized |

| WWW-Authenticate: Digest |

| (RAND, AUTN delivered) |

|<------------------------------------------------------|

| |

+------------------------------------+ |

| Client runs AKA algorithms on ISIM,| |

| verifies AUTN, derives RES | |

| and session keys. | |

+------------------------------------+ |

| |

| 3) REGISTER |

| Authorization: Digest (RES is used) |

|------------------------------------------------------>|

| |

| +------------------------------+

| | Server checks the given RES, |

| | and finds it correct. |

| +------------------------------+

| |

| 4) 200 OK |

| Authentication-Info: (XRES is used) |

|<------------------------------------------------------|

| |

Figure 2: Message flow representing a successful authentication.

1) Initial request

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RFC 3310 HTTP Digest Authentication Using AKA September 2002

2) Response containing a challenge

SIP/2.0 401 Unauthorized

WWW-Authenticate: Digest

realm="RoamingUsers@",

nonce="CjPk9mRqNuT25eRkajM09uTl9nM09uTl9nMz5OX25PZz==",

qop="auth,auth-int",

opaque="5ccc069c403ebaf9f0171e9517f40e41",

algorithm=AKAv1-MD5

3) Request containing credentials

Authorization: Digest

username="@",

realm="RoamingUsers@",

nonce="CjPk9mRqNuT25eRkajM09uTl9nM09uTl9nMz5OX25PZz==",

uri="sip:",

qop=auth-int,

nc=00000001,

cnonce="0a4f113b",

response="6629fae49393a07c4ef1",

opaque="5ccc069c403ebaf9f0171e9517f40e41"

4) Successful response

SIP/2.0 200 OK

Authentication-Info:

qop=auth-int,

rspauth="6629fae49393a07c4ef1",

cnonce="0a4f113b",

nc=00000001

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RFC 3310 HTTP Digest Authentication Using AKA September 2002

Figure 3 below describes a message flow describing a Digest AKA

authentication process, in which there is a synchronization failure.

Client Server

| 1) REGISTER |

|------------------------------------------------------>|

| |

| +-----------------------------+

| | Server runs AKA algorithms, |

| | generates RAND and AUTN. |

| +-----------------------------+

| |

| 2) 401 Unauthorized |

| WWW-Authenticate: Digest |

| (RAND, AUTN delivered) |

|<------------------------------------------------------|

| |

+------------------------------------+ |

| Client runs AKA algorithms on ISIM,| |

| verifies the AUTN, but discovers | |

| that it contains an invalid | |

| sequence number. The client then | |

| generates an AUTS token. | |

+------------------------------------+ |

| |

| 3) REGISTER |

| Authorization: Digest (AUTS is delivered) |

|------------------------------------------------------>|

| |

| +-----------------------+

| | Server performs |

| | re-synchronization |

| | using AUTS and RAND. |

| +-----------------------+

| |

| 4) 401 Unauthorized |

| WWW-Authenticate: Digest |

| (re-synchronized RAND, |

| AUTN delivered) |

|<------------------------------------------------------|

| |

Figure 3: Message flow representing an authentication synchronization

failure.

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RFC 3310 HTTP Digest Authentication Using AKA September 2002

1) Initial request

2) Response containing a challenge

SIP/2.0 401 Unauthorized

WWW-Authenticate: Digest

realm="RoamingUsers@",

qop="auth",

nonce="CjPk9mRqNuT25eRkajM09uTl9nM09uTl9nMz5OX25PZz==",

opaque="5ccc069c403ebaf9f0171e9517f40e41",

algorithm=AKAv1-MD5

3) Request containing credentials

Authorization: Digest

username="@",

realm="RoamingUsers@",

nonce="CjPk9mRqNuT25eRkajM09uTl9nM09uTl9nMz5OX25PZz==",

uri="sip:",

qop=auth,

nc=00000001,

cnonce="0a4f113b",

response="4429ffe49393c07c4ef1",

opaque="5ccc069c403ebaf9f0171e9517f40e41",

auts="5PYxMuX2NOT2NeQ="

4) Response containing a new challenge

SIP/2.0 401 Unauthorized

WWW-Authenticate: Digest

realm="RoamingUsers@",

qop="auth,auth-int",

nonce="9uQzNPbk9jM05Pbl5Pbl5DIz9uTl9uTl9jM0NTHk9uXk==",

opaque="dcd98b7102dd2f0e8b11d0f600bfb0c093",

algorithm=AKAv1-MD5

5. Security Considerations

In general, Digest AKA is vulnerable to the same security threats as

HTTP authentication [2]. This chapter discusses the relevant

exceptions.

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5.1 Authentication of Clients using Digest AKA

AKA is typically -- though this isn’t a theoretical limitation -- run

on an ISIM application that usually resides in a tamper resistant

smart card. Interfaces to the ISIM exist, which enable the host

device to request authentication to be performed on the card.

However, these interfaces do not allow access to the long-term secret

outside the ISIM, and the authentication can only be performed if the

device accessing the ISIM has knowledge of a PIN code, shared between

the user and the ISIM. Such PIN codes are typically obtained from

user input, and are usually required when the device is powered on.

The use of tamper resistant cards with secure interfaces implies that

Digest AKA is typically more secure than regular Digest

implementations, as neither possession of the host device nor Trojan

Horses in the software give access to the long term secret. Where a

PIN scheme is used, the user is also authenticated when the device is

powered on. However, there may be a difference in the resulting

security of Digest AKA, compared to traditional Digest

implementations, depending of course on whether those implementations

cache/store passwords that are received from the user.

5.2 Limited Use of Nonce Values

The Digest scheme uses server-specified nonce values to seed the

generation of the request-digest value. The server is free to

construct the nonce in such a way, that it may only be used from a

particular client, for a particular resource, for a limited period of

time or number of uses, or any other restrictions. Doing so

strengthens the protection provided against, for example, replay

attacks.

Digest AKA limits the applicability of a nonce value to a particular

ISIM. Typically, the ISIM is accessible only to one client device at

a time. However, the nonce values are strong and secure even though

limited to a particular ISIM. Additionally, this requires that the

server is provided with the client identity before an authentication

challenge can be generated. If a client identity is not available,

an additional round trip is needed to acquire it. Such a case is

analogous to an AKA synchronization failure.

A server may allow each nonce value to be used only once by sending a

next-nonce directive in the Authentication-Info header field of every

response. However, this may cause a synchronization failure, and

consequently some additional round trips in AKA, if the same SQN

space is also used for other access schemes at the same time.

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5.3 Multiple Authentication Schemes and Algorithms

In HTTP authentication, a user agent MUST choose the strongest

authentication scheme it understands and request credentials from the

user, based upon that challenge.

In general, using passwords generated by Digest AKA with other HTTP

authentication schemes is not recommended even though the realm

values or protection domains would coincide. In these cases, a

password should be requested from the end-user instead. Digest AKA

passwords MUST NOT be re-used with such HTTP authentication schemes,

which send the password in clear. In particular, AKA passwords MUST

NOT be re-used with HTTP Basic.

The same principle must be applied within a scheme if several

algorithms are supported. A client receiving an HTTP Digest

challenge with several available algorithms MUST choose the strongest

algorithm it understands. For example, Digest with "AKAv1-MD5" would

be stronger than Digest with "MD5".

5.4 Online Dictionary Attacks

Since user-selected passwords are typically quite simple, it has been

proposed that servers should not accept passwords for HTTP Digest,

which are in the dictionary [2]. This potential threat does not

exist in HTTP Digest AKA because the algorithm will use ISIM

originated passwords. However, the end-user must still be careful

with PIN codes. Even though HTTP Digest AKA password requests are

never displayed to the end-user, she will be authenticated to the

ISIM via a PIN code. Commonly known initial PIN codes are typically

installed to the ISIM during manufacturing and if the end-users do

not change them, there is a danger that an unauthorized user may be

able to use the device. Naturally this requires that the

unauthorized user has access to the physical device, and that the

end-user has not changed the initial PIN code. For this reason,

end-users are strongly encouraged to change their PIN codes when they

receive an ISIM.

5.5 Session Protection

Digest AKA is able to generate additional session keys for integrity

(IK) and confidentiality (CK) protection. Even though this document

does not specify the use of these additional keys, they may be used

for creating additional security within HTTP authentication or some

other security mechanism.

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5.6 Replay Protection

AKA allows sequence numbers to be tracked for each authentication,

with the SQN parameter. This allows authentications to be replay

protected even if the RAND parameter happened to be the same for two

authentication requests. More importantly, this offers additional

protection for the case where an attacker replays an old

authentication request sent by the network. The client will be able

to detect that the request is old, and refuse authentication. This

proves liveliness of the authentication request even in the case

where a MitM attacker tries to trick the client into providing an

authentication response, and then replaces parts of the message with

something else. In other words, a client challenged by Digest AKA is

not vulnerable for chosen plain text attacks. Finally, frequent

sequence number errors would reveal an attack where the tamper

resistant card has been cloned and is being used in multiple devices.

The downside of sequence number tracking is that servers must hold

more information for each user than just their long-term secret,

namely the current SQN value. However, this information is typically

not stored in the SIP nodes, but in dedicated authentication servers

instead.

5.7 Improvements to AKA Security

Even though AKA is perceived as a secure mechanism, Digest AKA is

able to improve it. More specifically, the AKA parameters carried

between the client and the server during authentication may be

protected along with other parts of the message by using Digest AKA.

This is not possible with plain AKA.

6. IANA Considerations

This document specifies an aka-version namespace in Section 3.1 which

requires a central coordinating body. The body responsible for this

coordination is the Internet Assigned Numbers Authority (IANA).

The default aka-version defined in this document is "AKAv1".

Following the policies outlined in [5], versions above 1 are

allocated as Expert Review.

Registrations with the IANA MUST include the version number being

registered, including the "AKAv" prefix. For example, a registration

for "AKAv2" would potentially be a valid one, whereas a registration

for "FOOv2" or "2" would not be valid. Further, the registration

MUST include contact information for the party responsible for the

registration.

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As this document defines the default aka-version, the initial IANA

registration for aka-version values will contain an entry for

"AKAv1".

6.1 Registration Template

To: ietf-digest-aka@

Subject: Registration of a new AKA version

Version identifier:

(Must contain a valid aka-version value,

as described in section 3.1.)

Person & email address to contact for further information:

(Must contain contact information for the

person(s) responsible for the registration.)

Normative References

[1] Bradner, S., "Key words for use in RFCs to Indicate Requirement

Levels", BCP 14, RFC 2119, March 1997.

[2] Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S.,

Leach, P., Luotonen, A. and L. Stewart, "HTTP Authentication:

Basic and Digest Access Authentication", RFC 2617, June 1999.

[3] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A.,

Peterson, J., Sparks, R., Handley, M. and E. Schooler, "SIP:

Session Initiation Protocol", RFC 3261, June 2002.

[4] Freed, N. and N. Borenstein, "Multipurpose Internet Mail

Extensions (MIME) Part One: Format of Internet Message Bodies",

RFC 2045, November 1996.

Informative References

[5] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA

Considerations Section in RFCs", BCP 26, RFC 2434, October 1998.

[6] 3rd Generation Partnership Project, "Security Architecture

(Release 4)", TS 33.102, December 2001.

[7] , "Assigned Numbers".

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RFC 3310 HTTP Digest Authentication Using AKA September 2002

Appendix A. Acknowledgements

The authors would like to thank Sanjoy Sen, Jonathan Rosenberg, Pete

McCann, Tao Haukka, Ilkka Uusitalo, Henry Haverinen, John Loughney,

Allison Mankin and Greg Rose.

Authors’ Addresses

Aki Niemi

Nokia

P.O. Box 301

NOKIA GROUP, FIN 00045

Finland

Phone: +358 50 389 1644

EMail: @

Jari Arkko

Ericsson

Hirsalantie 1

Jorvas, FIN 02420

Finland

Phone: +358 40 5079256

EMail: @

Vesa Torvinen

Ericsson

Joukahaisenkatu 1

Turku, FIN 20520

Finland

Phone: +358 40 7230822

EMail: en@

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RFC 3310 HTTP Digest Authentication Using AKA September 2002

Full Copyright Statement

This document and translations of it may be copied and furnished to

others, and derivative works that comment on or otherwise explain it

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