Internet DRAFT - draft-morand-http-digest-2g-aka
draft-morand-http-digest-2g-aka
Network Working Group L. Morand
Internet-Draft Orange Labs
Intended status: Informational April 14, 2014
Expires: October 16, 2014
Hypertext Transfer Protocol (HTTP) Digest Authentication Using GSM 2G
Authentication and Key Agreement (AKA)
draft-morand-http-digest-2g-aka-05
Abstract
This document specifies a one-time password generation mechanism for
Hypertext Transfer Protocol (HTTP) Digest access authentication based
on Global System for Mobile Communications (GSM) authentication and
key generation functions A3 and A8, also known as GSM AKA or 2G AKA.
The HTTP Authentication Framework includes two authentication
schemes: Basic and Digest. Both schemes employ a shared secret based
mechanism for access authentication. The GSM AKA mechanism performs
user authentication and session key distribution in GSM and Universal
Mobile Telecommunications System (UMTS) networks. GSM AKA is a
challenge-response based mechanism that uses symmetric cryptography.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on October 16, 2014.
Copyright Notice
Copyright (c) 2014 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
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publication of this document. Please review these documents
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Table of Contents
1. Introduction and Motivations . . . . . . . . . . . . . . . . 2
1.1. Motivation . . . . . . . . . . . . . . . . . . . . . . . 2
1.2. Relationship with 3GPP authentication mechanism over HTTP 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4. GSM 2G AKA Mechanism Overview . . . . . . . . . . . . . . . . 4
5. Example of Digest 2G AKA operations . . . . . . . . . . . . . 6
6. Specification of Digest 2G AKA . . . . . . . . . . . . . . . 8
6.1. Algorithm Directive . . . . . . . . . . . . . . . . . . . 9
6.2. Creating a Challenge . . . . . . . . . . . . . . . . . . 9
6.3. Client Authentication . . . . . . . . . . . . . . . . . . 10
6.4. Server Authentication . . . . . . . . . . . . . . . . . . 10
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
8. Security Considerations . . . . . . . . . . . . . . . . . . . 10
8.1. Authentication of Clients using Digest 2G AKA . . . . . . 10
8.2. Limited Use of Nonce Values . . . . . . . . . . . . . . . 11
8.3. Multiple Authentication Schemes and Algorithms . . . . . 11
8.4. Online Dictionary Attacks . . . . . . . . . . . . . . . . 12
8.5. Session Protection . . . . . . . . . . . . . . . . . . . 12
8.6. Replay Protection . . . . . . . . . . . . . . . . . . . . 12
8.7. Mutual Authentication . . . . . . . . . . . . . . . . . . 13
8.8. Flooding the Authentication Centre . . . . . . . . . . . 13
8.9. AKA Security . . . . . . . . . . . . . . . . . . . . . . 13
8.10. TLS Profile . . . . . . . . . . . . . . . . . . . . . . . 14
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 15
10.1. Normative References . . . . . . . . . . . . . . . . . . 15
10.2. Informative References . . . . . . . . . . . . . . . . . 15
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 16
1. Introduction and Motivations
1.1. Motivation
The Hypertext Transfer Protocol (HTTP) Authentication Framework,
described in [RFC2617], 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
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improves security by hiding user credentials with cryptographic
hashes, and additionally by providing limited message integrity.
The 2G AKA functions [TS55.205] perform authentication and session
key distribution in Global System for Mobile Communication (GSM) and
Universal Mobile Telecommunications System (UMTS) networks. 2G AKA is
a challenge-response based mechanism that uses symmetric
cryptography. 2G AKA is typically run in a GSM Subscriber Identity
Module (SIM), which resides in a smart card like device that also
provides tamper resistant storage of shared secrets. The 3G
Authentication and Key Agreement (AKA) mechanism, also known as UMTS
AKA, relying on the use of the UMTS Subscriber Identity Module (USIM)
instead of the GSM SIM, is most closely associated with UMTS;
however, mobile operators commonly distribute GSM SIMs with UMTS
mobile phones, resulting in the use of 2G (GSM) AKA in place of UMTS
AKA.
This document specifies a mapping of GSM AKA parameters onto HTTP
Digest authentication. In essence, this mapping enables the usage of
GSM 2G AKA as a one-time password generation mechanism for Digest
authentication.
This document is based heavily on [RFC3310] which specified a mapping
of Authentication and Key Agreement (AKA) onto HTTP Digest
authentication. While Digest AKA can be generally used when the
mobile phones are equipped with a UMTS SIM card, it may be useful for
mobile operators who have not yet fully deployed USIMs and have still
millions of SIMs deployed in the network. Digest 2G AKA allows
access to applications in a more secure way than would be possible
with the use of passwords or with GSM without enhancements.
Moreover, as the Session Initiation Protocol (SIP) [RFC3261]
Authentication Framework closely follows the HTTP Authentication
Framework, Digest 2G AKA is directly applicable to SIP as well as to
any other embodiment of HTTP Digest.
1.2. Relationship with 3GPP authentication mechanism over HTTP
3GPP has defined the Generic Bootstrapping Architecture (GBA) that
enables the authentication of mobile subscriber based on AKA protocol
[TS33.220]. This architecture is originally designed to allow 3G AKA
authentication over HTTP [RFC3310], involving the user's mobile
smartcard, a bootstrapping server function (BSF) and the
authentication center (AuC) colocated with the mobile subscriber
profile repository in the mobile operator network (HLR/HSS). GBA
also provides the optional support of authentication of 2G mobile
users with the procedure called 2G GBA. This document does not
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intend to define a new standard mechanism for 3GPP. The aim of this
document is to provide mobile operators with an 2G-AKA authentication
mechanism over HTTP in networks when no GBA is deployed in the mobile
operator network. When the GBA architecture is deployed in the
mobile operator network, it is recomment to rely on the 3GPP TS
33.220 [TS33.220] to perform 2G-AKA autentication over HTTP instead
of the mechanism described in this document.
2. Terminology
3. Acronyms
AuC Authentication Center.
AKA Authentication and Key Agreement.
GSM Global System for Mobile Communication.
IMS IP Multimedia Subsystem.
IMSI International Mobile Subscriber Identity
ISIM IMS Subscriber Identity Module.
Kc Cipher Key.
Ki Subscriber Key.
RAND Random Challenge.
SIM Subscriber Identity Module.
SRES Signed Authentication Response.
UMTS Universal Mobile Telecommunications System.
USIM UMTS Subscriber Identity Module.
4. GSM 2G AKA Mechanism Overview
This following figure (Fig. 1) provides an overview of the GSM 2G AKA
mechanism, which is based on a shared secret key (Ki) and the use of
A3/A8 algorithms.
The GSM 2G AKA mechanism is a challenge-response mechanism that
allows the authentication of the mobile subscriber/device in the
network. This mechanism involves the Subscriber Identity Module
(SIM) hosted by the mobile subscriber's device, a server in the
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serving network and the Authentication Centre (AuC) in the mobile
subscriber's home network. When required, the authentication of the
mobile subscriber is performed by the serving network using
authentication material provided by the AuC.
A shared secret (Ki) is established beforehand between the SIM and
the AuC. The secret is stored in the SIM, which resides on a smart
card like, tamper resistant device. The SIM is identified by the
IMSI (International Mobile Subscriber Identity), which is also used
to identify the mobile subscriber/device in the network and the
shared secret (Ki) in the AuC (Authentication Center).
SIM Server AuC
(Ki) (Ki)
| | |
|---- 1.Request (IMSI) ----->| |
| | 2.Authen. Data Request (IMSI) |
| |------------------------------>|
| | |
| | +-----------------+----+
| | | (3) |
| | | IMSI --> Ki |
| | | A3(RAND,Ki) = SRES |
| | | A8(RAND,Ki) = Kc |
| | +----------------+-----+
| | |
| |<--- 4.AV (RAND, SRES, Kc) ---|
|<-- 5.Auth. Request (RAND) -| |
| | |
+-----+---------------+ | |
| (6) | | |
| A3(RAND,Ki) = SRES* | | |
| A8(RAND,Ki) = Kc | | |
+-----+---------------+ | |
| | |
|- 7.Auth. Response (SRES*)->| |
| | |
| +-------+------+ |
| | (8) | |
| | SRES*= SRES? | |
| +-------+------+ |
| | |
Figure 1. GSM 2G AKA overview
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1. The mobile subscriber initiates a access/service request towards a
server in the serving network. The request contains the IMSI.
2. When the request needs to be authenticated, the server queries
the AuC of the mobile subscriber's home network to retrieve the
necessary material for authenticating the mobile subscriber
identified by the IMSI.
3. The IMSI received from the server is used as key entry by the AuC
to select the corresponding shared secret Ki. The AuC uses the
shared secret Ki and a generated random value (RAND) for calculating
the expected response (SRES) using the A3 algorithm and the cipher
key Kc using the A8 algorithm. the triple RAND, SRES and Kc form an
Authentication Vector (AV).
4. The authentication vector (RAND, SRES, Kc) is downloaded to a
server. Optionally, if request by the server, the AuC can
also download more than one authentication vector, each AV generated
with a different RAND value.
5. The server creates an authentication request, which contains the
random challenge RAND and the authentication request is delivered
to the client.
6. The client produces a authentication response RES, using
the shared secret Ki and the random challenge RAND provided in
the authentication request received from the server.
7. The authentication response RES is delivered to the server.
8. The server compares the authentication response RES with the
expected response SRES. If the two match, the user has been
successfully authenticated, and the session key Kc can be used
for protecting further communication between the client and the
server
5. Example of Digest 2G AKA operations
Figure 2 below describes a message flow describing a Digest 2G AKA
process of authenticating a SIP request, namely the SIP REGISTER
request.
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SIM HTTP Server AuC
(Ki) (Ki)
| 1) GET (IMSI) | |
|--------------------------->| |
| | 2) Authen. Data Request (IMSI)|
| |------------------------------>|
| | |
| | +-----------------+--+
| | | IMSI --> Ki |
| | | A3(RAND,Ki) = SRES |
| | | A8(RAND,Ki) = Kc |
| | +-----------------+--+
| | |
| | 3) AV (RAND, SRES, Kc) |
| |<------------------------------|
| 4) 401 Unauthorized (RAND) | |
|<---------------------------| |
| | |
+-----+---------------+ | |
| A3(RAND,Ki) = SRES* | | |
| A8(RAND,Ki) = Kc | | |
+-----+---------------+ | |
| | |
| 5) GET (IMSI, RAND, SRES) | |
|--------------------------->| |
| | |
| +-------+------+ |
| | SRES*= SRES? | |
| +-------+------+ |
| | |
| 6) 200 OK | |
|<---------------------------| |
| | |
Figure 2: Message flow representing a successful authentication
1) Initial request
GET / HTTP/1.1
Authorization: Digest
username="user1_private@home1.net",
realm="service1.home1.net",
nonce="",
uri="/",
response=""
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2) Request to the AuC for 2G AKA authentication vector (AV) for the
given IMSI
3) Response from the AuC providing 2G AKA AV (RAND, SRES, Kc)
associated with the IMSI
4) Response containing a challenge
HTTP/1.1 401 Unauthorized
WWW-Authenticate: Digest
realm="service1.home1.net",
nonce="base64(RAND)",
qop="auth,auth-int",
opaque="6dae728da9089dab9112373c9f0a9731",
algorithm=2GAKA-MD5
5) Request containing credentials
GET / HTTP/1.1
Authorization: Digest
username="user1_private@home1.net",
realm="service1.home1.net",
nonce="base64(RAND)",
uri="/",
nc=00000001,
cnonce="0b8f29d6",
response="6629fae49393a05397450978507c4ef1",
opaque="6dae728da9089dab9112373c9f0a9731",
algorithm=2GAKA-MD5
6) Successful response
HTTP/1.1 200 OK
Authentication-Info:
qop=auth-int,
rspauth="6629fae49394a05397450978507c4ef1",
cnonce="6629fae49393a05397450978507c4ef1",
nc=00000001,
opaque="6dae728da9089dab9112373c9f0a9731",
nonce="base64(RAND)"
6. Specification of Digest 2G AKA
In general, the Digest 2G AKA operation is identical to the Digest
operation in [RFC2617]. This chapter specifies the parts in which
Digest 2G 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 [RFC3261], and any elements not
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defined in this section are as defined in SIP and the documents to
which it refers.
6.1. Algorithm Directive
In order to direct the client into using 2G AKA for authentication
instead of the standard password system, the RFC 2617 defined
algorithm directive is overloaded in Digest 2G AKA:
algorithm = "algorithm" EQUAL ( 2GAKA-namespace / algorithm-value
)
2GAKA-namespace = "2GAKA" "-" algorithm-value
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. Reuse of the same SRES value in
authenticating subsequent requests and responses is NOT
RECOMMENDED. An SRES 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.
6.2. Creating a Challenge
In order to deliver the GSM 2G AKA authentication challenge to the
client in Digest 2G AKA, the nonce directive defined in [RFC2617] is
extended:
nonce = "nonce" EQUAL ( 2GAKA-nonce / nonce-value )
2GAKA-nonce = LDQUOT 2GAKA-nonce-value RDQUOT
2GAKA-nonce-value = <base64 encoding of RAND>
nonce
A parameter which is populated with the Base64 [RFC2045] encoding
of the 2G AKA authentication random challenge RAND.
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6.3. Client Authentication
When a client receives a Digest 2G AKA authentication challenge, it
extracts the RAND from the "nonce" parameter and runs the A3-A8
algorithms with the RAND challenge and shared secret Ki.
The resulting A3-A8 SRES parameter is treated as a "password" when
calculating the response directive of [RFC2617]. Due to the fact
that the SRES parameter is 32 bits and the response directive of
[RFC2617] is defined as 32 hex digits, SRES is encoded in the low
order (i.e. rightmost) 32 bits of "response", padded with leading
zeroes.
Example:
SRES="0000000000000000000000007018d8a1"
6.4. Server Authentication
With Digest 2G AKA, the server MUST use the expected response SRES
received in the authentication vector as "password" when calculating
the "response-auth" of the "Authentication-Info" header defined in
[RFC2617].
7. IANA Considerations
IANA is kinly requested to register the following fields in the HTTP
Authentication Scheme Registry:
o Authentication Scheme Name: Digest-2G-AKA
o Pointer to specification text: draft-morand-http-digest-2g-aka-05
o Notes: This document specifies a mapping of GSM AKA parameters
onto HTTP Digest authentication independent of the GBA
architecture defined by 3GPP.
8. Security Considerations
In general, Digest 2G AKA is vulnerable to the same security threats
as HTTP authentication [RFC2617]. This chapter discusses the
relevant exceptions.
8.1. Authentication of Clients using Digest 2G AKA
2G AKA is typically -- though this isn't a theoretical limitation --
run on a SIM application that usually resides in a tamper resistant
smart card. Interfaces to the SIM exist, which enable the host
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device to request authentication to be performed on the card.
However, these interfaces do not allow access to the long-term secret
outside the SIM, and the authentication can only be performed if the
device accessing the SIM has knowledge of a PIN code, shared between
the user and the SIM. 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 2G 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 2G AKA, compared to traditional Digest
implementations, depending on whether those implementations cache/
store passwords that are received from the user.
8.2. 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 or uses, or any other restrictions. Doing so
strengthens the protection provided against, for example, replay
attacks.
Digest 2G AKA limits the applicability of a nonce value to a
particular SIM. Typically, the SIM is accessible only to one client
device at a time. However, the nonce values are strong and secure
even though limited to a particular SIM. 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.
8.3. 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 2G 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 2G
AKA passwords MUST NOT be re-used with such HTTP authentication
schemes, which send the password in the clear. In particular, 2G AKA
passwords must not be re-used with HTTP Basic.
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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 "2GAKA-MD5" would
be stronger than Digest with "MD5".
8.4. 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 [RFC2617]. This potential threat does
not exist in HTTP Digest 2G AKA because the algorithm will use SIM
originated passwords. However, the end-user must still be careful
with PIN codes. Even though HTTP Digest 2G AKA password requests are
never displayed to the end-user, the end-user will be authenticated
to the SIM via a PIN code. Commonly known initial PIN codes are
typically installed to the SIM during manufacturing and if the end-
users do not change them, there is a danger than 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 a SIM.
8.5. Session Protection
Digest 2G AKA is able to generate an additional session key for
integrity (Kc) 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 mechanisms.
8.6. Replay Protection
The generation of RAND used as one-time or very limited-use nonces
and the use of the integrity protection of qop=auth-int will limit
the possibility of replay attacks.
In GSM, the network is allowed to re-use the RAND challenge in
consecutive authentication exchanges. This is not allowed in Digest
2G AKA. The server is mandated to use fresh triplets (RAND
challenges) in consecutive authentication exchanges. Digest 2G AKA
does not mandate any means for the client to check if the RANDs are
fresh, so the security of the scheme leans on the secrecy of the
triplets. However, the peer MAY employ implementation-specific
mechanisms to remember some of the previously used RANDs, and the
client MAY check the freshness of the server's RANDs.
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8.7. Mutual Authentication
With Digest 2G AKA, network authentication is performed only after
client authentication, in contrary to Digest AKA [RFC3310] in which
the UE authenticates the network before responding to the challenge.
To prevent an impersonation attack of the server to the client, the
authentication of the server to the UE SHOULD be improved by
protecting the communication with Transport Layer Security (TLS). An
attacker succeeds only if he can break both, the certificate-based
TLS authentication to the client and mutual authentication provided
by HTTP Digest using a password derived from GSM procedures. One way
to break TLS is to compromise the certificate. However, the risk of
clients using the root certificates associated with a compromised
Certification Authority (CA) is minimized if the clients use a
preconfigured list of trusted root certificates restricted to a low
number of CAs trusted by the operator, as opposed to the list of all
root certificates in a browser's key store, as described in section
8.10.
When TLS is used for server authentication, the recommendations given
in section 8.10 apply.
8.8. Flooding the Authentication Centre
The server typically obtains authentication vectors from the
Authentication Centre (AuC). Digest 2G AKA introduces a new usage
for the AuC. The protocols between the server and the AuC are out of
the scope of this document. However, it should be noted that a
malicious client may generate a lot of protocol requests to mount a
denial of service attack. The server implementation SHOULD take this
into account and SHOULD take steps to limit the traffic that it
generates towards the AuC, preventing the attacker from flooding the
AuC and from extending the denial of service attack from Digest 2G
AKA to other users of the AuC.
8.9. AKA Security
Evolutions of GSM networks, specifically Universal Mobile
Telecommunications System (UMTS) and IP Multimedia System (IMS)
networks, use an enhanced shared secret based mechanism for
authentication known as Authentication and Key Agreement (AKA). In
these networks, AKA is typically run in a UMTS Services Identity
Module (USIM) or IP Multimedia Services Identity Module (ISIM). GSM
phones can also be equipped with a USIM or ISIM. In that case,
Digest AKA as described in [RFC3310] is used for authentication as
opposed to Digest 2G AKA.
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8.10. TLS Profile
When TLS is used for server authentication prior to the Digest 2G AKA
authentication procedures, the following recommendations apply.
o The TLS endpoints MUST support TLS version 1.1 as specified in RFC
4346 [RFC4346] and SHOULD support TLS version 1.2 as specified in
RFC 5246 [RFC5246] should be supported. -
o The highest TLS version supported on both TLS endpoints MUST be
used.
o The TLS endpoints MUST comply with the 3GPP TLS profile given in
3GPP TS 33.310, Annex E [TS33.310] is . The only difference is
that TLS cipher suites without encryption MUST not be used.
o The certificates used for TLS MUST comply with the 3GPP
certificate profile defined in the section 6.1 of 3GPP TS 33.310
[TS33.310] is .
o Support of certificate revocation and of the related fields in
certificates is recommended.
o Server name matching MUST be performed by the client using the
matching rules specified by RFC 2818 [RFC2818] is .
o The client MUST use a preconfigured list of trusted root
certificates for server certificate validation.
o Server certificate validation MUST not require manual user
interaction.
o The server MUST not request a certificate in a Server Hello
Message from the client (as the client is authenticated using
Digest 2G AKA as described in section 5).
o The TLS endpoints MUST allow for resuming a session. The lifetime
of a Session ID is subject to local policies set on the TLS
endpoints.
9. Acknowledgements
This memo is based on an initial draft written by Brett Wallis
(draft-ietf-http-digest-auth-a3a8-01).
The authors would like to thank Yoav Nir, Yaron Sheffer, Mark
Nottingham, Sean Turner, Jari Arkko, Barry Leiba, Adrian Farrel,
Stephen Farrell, Nevil Brownlee, Loic Habermacher, Bengt Sahlin and
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Stefan Schroeder for their valuable comments before, during and after
IESG review.
10. References
10.1. Normative References
[RFC2045] Freed, N. and N. Borenstein, "Multipurpose Internet Mail
Extensions (MIME) Part One: Format of Internet Message
Bodies", RFC 2045, November 1996.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2617] 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.
10.2. Informative References
[RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818, May 2000.
[RFC3261] 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.
[RFC3310] Niemi, A., Arkko, J., and V. Torvinen, "Hypertext Transfer
Protocol (HTTP) Digest Authentication Using Authentication
and Key Agreement (AKA)", RFC 3310, September 2002.
[RFC4346] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.1", RFC 4346, April 2006.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246, August 2008.
[TS33.220]
"Generic Bootstrapping Architecture (GBA)", December 2013.
[TS33.310]
"Network Domain Security (NDS); Authentication Framework
(AF) (Release 12)", June 2013.
[TS55.205]
"Specification of the GSM- MILENAGE algorithms (Release
11)", September 2012.
Morand Expires October 16, 2014 [Page 15]
Internet-Draft HTTP Digest 2G AKA April 2014
Author's Address
Lionel Morand
Orange Labs
38/40 rue du General Leclerc
Issy-Les-Moulineaux Cedex 9 92794
France
Phone: +33145296257
Email: lionel.morand@orange.com
Morand Expires October 16, 2014 [Page 16]
