EAP
Internet Draft H. Tschofenig
D. Kroeselberg
Siemens
Y. Ohba
Toshiba
Document: draft-tschofenig-eap-ikev2-02.txt
Expires: April 2002 October 2003
EAP IKEv2 Method
(EAP-IKEv2)
Status of this Memo
This document is an Internet-Draft and is subject to all provisions
of Section 10 of RFC2026.
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Abstract
EAP-IKEv2 is an EAP method which reuses the cryptography and the
payloads of IKEv2, creating a flexible EAP method that supports both
symmetric and asymmetric authentication. Furthermore protection of
legacy authentication mechanisms is supported. This EAP method
offers the security benefits of IKEv2 without the goal of
establishing IPsec security associations.
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Table of Contents
1. Introduction..................................................2
2. IKEv2 and EAP-IKEv2 Overview..................................3
3. Terminology...................................................4
4. Protocol overview.............................................4
5. Identities used in EAP-IKEv2..................................7
6. Packet Format.................................................9
7. Retransmission...............................................10
8. Key derivation...............................................10
9. Error Handling...............................................11
10. Security Considerations.....................................13
11. Open Issues.................................................13
12. Normative References........................................13
13. Informative References......................................14
Acknowledgments.................................................14
Author's Addresses..............................................15
Full Copyright Statement........................................15
1. Introduction
This document specifies the EAP-IKEv2 authentication method. EAP-
IKEv2 is a flexible EAP method which makes the IKEv2 protocolÆs
features available for scenarios using EAP-based authentication.
The main advantage of EAP-IKEv2 is that it does not define a new
cryptographic protocol, but re-uses the IKEv2 authentication
protocol, and thereby provides strong, well-analyzed, cryptographic
properties as well as broad flexibility. This includes the support
of authentication methods and configuration payloads for remote
access scenarios.
EAP-IKEv2 can be used directly to mutually authenticate EAP peers.
This may be based on either symmetric methods using pre-shared keys,
or on asymmetric methods based on public/private key pairs,
Certificates and CRLs. In addition, EAP-IKEv2 supports two-phased
authentication schemes by establishing a server-authenticated secure
tunnel, and by subsequently protecting an EAP authentication
allowing for legacy client authentication methods. Hence, EAP-IKEv2
provides a secure EAP tunneling method.
A non-goal of EAP-IKEv2 (and basically the major difference to plain
IKEv2) is the establishment of IPsec security associations, as this
would not make much sense in the standard AAA three-party scenario,
consisting of an EAP peer, an authenticator (NAS) and a back-end
authentication server terminating EAP. IPsec SA establishment may be
required locally (i.e., between the EAP peer and some access
server). However, SA establishment within an EAP method would only
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provide SAs between the EAP peer and the back-end authentication
server. Other approaches as e.g., those of the IETF PANA group are
considered more appropriate in this case.
2. IKEv2 and EAP-IKEv2 Overview
IKEv2 [Kau03] is a protocol which consists of two exchanges:
(1) an authentication and key exchange protocol which establishes an
IKE-SA.
(2) messages and payloads which focus on the negotiation of
parameters in order to establish IPsec security associations (i.e.,
Child-SAs). These payloads contain algorithm parameters and traffic
selector fields.
In addition to the above-mentioned parts IKEv2 also includes some
payloads and messages which allow configuration parameters to be
exchanged primarily for remote access scenarios.
The EAP-IKEv2 method defined by this document uses the IKEv2
payloads and messages used for the initial IKEv2 exchange which
establishes an IKE-SA.
IKEv2 provides an improvement over IKEv1 [RFC2409] as described in
Appendix A of [Kau03]. Important for this document are the reduced
number of initial exchanges, support of legacy authentication,
decreased latency of the initial exchange, optional Denial-of-
Service (DoS) protection capability and some other fixes (e.g., hash
problem). IKEv2 is a cryptographically sound protocol that has
received a considerable amount of expert review and that benefits
from a long practical experience with IKE.
The goal of EAP-IKEv2 is to inherit these properties within an
efficient, secure EAP method.
In addition, IKEv2 provides authentication and key exchange
capabilities which allow an entity to use symmetric as well as
asymmetric authentication within a single protocol. Such flexibility
is considered important for an EAP method and is provided by EAP-
IKEv2.
[Per03] provides a good tutorial for IKEv2 design decisions.
EAP-IKEv2 therefore provides
a) well-known IKEv2 symmetric/asymmetric authentication and
b) a new EAP tunneling method.
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EAP-IKEv2 provides a secure fragmentation mechanism in which
integrity protection is performed for each fragment of an IKEv2
message.
3. Terminology
This document does not introduce new terms other than those defined
in [RFC2284] or in [Kau03].
The keywords MUST, MUST NOT, REQUIRED, SHALL, SHALL NOT, SHOULD,
SHOULD NOT, RECOMMENDED, MAY, and OPTIONAL, when they appear in this
document, are to be interpreted as described in [RFC2119].
4. Protocol overview
This section provides some overview over EAP-IKEv2 message
exchanges. Note that some payloads are omitted (such as SAi2 and
SAr2) which are mandatory for IKEv2 but are not required in EAP-
IKEv2 since they are used to establish an IPsec SA.
IKEv2 uses the same protocol message exchanges for both symmetric
and asymmetric authentication. The difference lies only in the
computation of the AUTH payload. See Section 2.15 of [Kau03] for
more information about the details of the AUTH payload computation.
It is even possible to combine symmetric (e.g., from the client to
the server) with asymmetric authentication (e.g., from the server to
the client) in a single protocol exchange. Figure 1 depicts such a
protocol exchange.
Message exchanges are reused from [Kau03], and are adapted. Since
this document does not describe frameworks or particular
architectures the message exchange takes place between two parties -
between the Initiator (I) and the Responder (R). In context of EAP
the Initiator is often called Authenticating Peer whereas the
Responder is referred as Authenticator.
The first message flow shows EAP-IKEv2 without the optional DoS
protection exchanges. The core EAP-IKEv2 exchange (message (4) -
(7)) consists of four messages (two round trips)_only. The first two
messages constitute the standard EAP identity exchange and are not
mandatory if the EAP server is known.
1) I <-- R: EAP-Request/Identity
2) I --> R: EAP-Response/Identity(Id)
3) I <-- R: EAP-Request/EAP-Type=EAP-IKEv2(Start)
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4) I --> R: EAP-Response/EAP-Type=EAP-IKEv2(HDR(A,0), SAi1, KEi, Ni)
5) I <-- R: EAP-Request/EAP-Type=EAP-IKEv2(
HDR(A,B), SAr1, KEr, Nr, [CERTREQ])
6) I --> R: EAP-Response/EAP-Type=EAP-IKEv2(
HDR(A,B), SK {IDi, [CERT,] [CERTREQ,] [IDr,], AUTH})
7) I <-- R: EAP-Request/EAP-Type=EAP-IKEv2(
HDR(A,B), SK {IDr, [CERT,] AUTH})
8) I --> R: EAP-Response/EAP-Type=EAP-IKEv2(Finish)
9) I <-- R: EAP-Success
Figure 1: EAP-IKEv2 message flow
The subsequent message flow shows EAP-IKEv2 with DoS protection
enabled. The IKEv2 DoS protection mechanism uses cookies and keeps
the responder stateless when it receives the first IKEv2 message,
preventing it from performing heavy cryptographic operations based
on this first incoming message. As a consequence of DoS protection
an additional round trip (message (5) and (6)) is required.
1) I <-- R: EAP-Request/Identity
2) I --> R: EAP-Response/Identity(Id)
3) I <-- R: EAP-Request/EAP-Type=EAP-IKEv2(Start)
4) I --> R: EAP-Response/EAP-Type=EAP-IKEv2(HDR(A,0), SAi1, KEi, Ni)
5) I <-- R: EAP-Request/EAP-Type=EAP-IKEv2(
HDR(A,0), N(COOKIE-REQUIRED), N(COOKIE))
6) I --> R: EAP-Response/EAP-Type=EAP-IKEv2(
HDR(A,0), N(COOKIE), SAi1, KEi, Ni)
7) I <-- R: EAP-Request/EAP-Type=EAP-IKEv2(
HDR(A,B), SAr1, KEr, Nr, [CERTREQ])
8) I --> R: EAP-Response/EAP-Type=EAP-IKEv2(
HDR(A,B), SK {IDi, [CERT,] [CERTREQ,] [IDr,], AUTH})
9) I <-- R: EAP-Request/EAP-Type=EAP-IKEv2(
HDR(A,B), SK {IDr, [CERT,] AUTH})
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10) I --> R: EAP-Response/EAP-Type=EAP-IKEv2(Finish)
11) I <-- R: EAP-Success
Figure 2: EAP-IKEv2 with Cookies
The Secure Legacy Authentication (SLA) EAP message exchange shown in
Figure 3 is taken from Section 2.16 of [Kau03] and adapted. It
provides an example of a successful inner EAP exchange using the
EAP-SIM Authentication method [HS03], which is secured by the IKE-
SA.
Implementations MUST ensure that infinite recursions of EAP and EAP-
IKEv2 exchanges are not allowed. (TBD: some limit necessary)
I <-- R: EAP-Request/Identity
I --> R: EAP-Response/Identity(Id)
I <-- R: EAP-Request/EAP-Type=EAP-IKEv2(Start)
I --> R: EAP-Response/EAP-Type=EAP-IKEv2(
HDR, SAi1, KEi, Ni)
I <-- R: EAP-Request/EAP-Type=EAP-IKEv2(
HDR, SAr1, KEr, Nr, [CERTREQ])
I --> R: EAP-Response/EAP-Type=EAP-IKEv2(
HDR, SK {IDi, [CERTREQ,] [IDr,]})
I <-- R: EAP-Request/EAP-Type=EAP-IKEv2(HDR,
SK {IDr, [CERT,] AUTH, EAP(EAP-Request /SIM
/Start(AT_VERSION_LIST))})
I --> R: EAP-Response/EAP-Type=EAP-IKEv2(HDR, SK {EAP(EAP-
Response/SIM/Start(AT_NONCE_MT, AT_SELECTED_VERSION)),
[AUTH]})
I <-- R: EAP-Request/EAP-Type=EAP-IKEv2(HDR, SK {EAP(EAP-
Request/SIM/Challenge(AT_RAND, AT_MAC)), [AUTH]})
I --> R: EAP-Response/EAP-Type=EAP-IKEv2(
HDR, SK {EAP(EAP-Response/SIM/Challenge(AT_MAC) ), [AUTH]})
I <-- R: EAP-Success
Figure 3: EAP-IKEv2 SLA with EAP-SIM Authentication
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Please note that the message flow in Figure 3 does not include an
EAP-Request/Identity and the corresponding EAP-Response/Identity
message inside the EAP-IKEv2 tunnel. Although it would be possible
to perform such an exchange IKEv2 suggests using the IDi payload for
this purpose. As a consequence the initiators identity is not
protected against active attacks.
Since the goal of this EAP method is not to establish an IPsec SA
some payloads used in IKEv2 are omitted. In particularly the
following messages and payloads are not required:
- Traffic Selectors
- IPsec SA negotiation payloads
(e.g., CREATE_CHILD_SA exchange or SAx2 payloads)
- ECN Notification
- Port handling
- NAT traversal
Some of these messages and payloads are optional in IKEv2.
In general it does not make sense to directly negotiate IPsec SAs
with EAP-IKEv2, as such SAs were unlikely to be used between the EAP
endpoints.
IKEv2 also provides functionality for the initiator to request
address information from the responder as described in Section 2.19
of [Kau03]. Using this functionality it is possible for an end host
to securely request address configuration information from the local
network.
5. Identities used in EAP-IKEv2
A number of different places allow to convey identity information in
IKEv2, when combined with EAP. This section describes their function
within the different exchanges of EAP-IKEv2. Note that EAP-IKEv2
does not introduce more identities than any other tunneling
approach. Figure 4 shows which identities are used during the
individual phases of the protocol.
+-------+ +-------------+ +---------+ +--------+
|Client | |Front-End | |Local AAA| |Home AAA|
| | |Authenticator| |Server | |Server |
+-------+ +-------------+ +---------+ +--------+
EAP/Identity-Request
<---------------------
(a) EAP/Identity-Response
---------------------------------->
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Tunnel-Establishment
(b) (Identities of IKEv2 are used)
Server (Network) Authentication
<----------------------------------
...
---------------------------------->
+---------------------------------+
| Secure Tunnel |
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~+
| Secure Legacy Authentication |
| protected with the IKE-SA |
(c) | (Identities of the tunneled |
| EAP method are used) |
| Client Authentication |
|---------------------------------+---------------->
|<--------------------------------+-----------------
+---------------------------------+
Figure 4: Identities used in EAP-IKEv2
a) The first part of the (outer) EAP message exchange provides
information about the identities of the EAP endpoints. This message
exchange mainly is an identity request/response. This exchange is
optional if the EAP server is known already or can be learned by
other means.
b) The identities used within EAP-IKEv2 for both the initiator and
the responder. The initiator identity is often associated with a
user identity such as a fully-qualified RFC 822 email address. The
identity of the responder might be a FQDN. The identity is of
importance for authorization.
c) For secure legacy authentication an EAP message exchange is
protected with the established IKE-SA as shown in Figure 3. This
exchange again adds EAP identities.
This inner EAP message exchange serves the purpose of client
authentication. The two identities used thereby are the EAP identity
(i.e., a NAI) and possibly a separate identity for the selected EAP
method.
The large number of identities is required due to nesting of
authentication methods and due to overloaded function of the
identity for routing (i.e., authentication end point indication).
The number of recursions of EAP and IKEv2 is limited, see Section 4.
Hence with this additional (nested) EAP exchange the end point of
the EAP-IKEv2 exchange might not be the same as the end point of the
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inner EAP exchange which is protected by the IKE-SA (which in this
case is not protected by the IKE-SA any more between the EAP-IKEv2
endpoint and the endpoint of the inner EAP exchange, but might be
protected by other means that are not considered in this document).
6. Packet Format
The IKEv2 payloads, which are defined in [Kau03], are embedded into
the Data field of the standard EAP Request/Response packets. The
Code, Identifier, Length and Type field is described in [RFC2284].
The Type-Data field carries a one byte Flags field following the
IKEv2 payloads. Each IKEv2 payload starts with a header field HDR
(see [Kau03]).
The packet format is shown in Figure 5.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Code | Identifier | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Flags | Message Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Length | Data ... ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Integrity Checksum Data |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: Packet Format
No additional packet formats other than those defined in [Kau03] are
required for this EAP method.
The Flags field is required to indicate Start and Finish messages
which are required due to the asymmetric nature of IKEv2 and the
Request/Response message handling of EAP.
Currently five bits of the eight bit flags field are defined. The
remaining bits are set to zero.
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
|S F L M 0 0 0 0|
+-+-+-+-+-+-+-+-+
S = EAP-IKEv2 start message
F = EAP-IKEv2 finish message
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L = Length included
M = More fragments
I = Integrity Checksum Data included
EAP-IKEv2 messages which have neither the S nor the F flag set
contain regular IKEv2 message payloads inside the Data field.
With regard to fragmentation we follow the suggestions and
descriptions given in Section 2.8 of [PS+03]: The L indicates that a
length field is present and the M flag indicates fragments. The L
flag MUST be set for the first fragment and the M flag MUST be set
on all fragments expect for the last one. Each fragment sent must
subsequently be acknowledged.
The Message Length field is four octets long and present only if the
L bit is set. This field provides the total message length that is
being fragmented (i.e., the length of the Data field.).
The Integrity Checksum Data is the cryptographic checksum of the
entire EAP message starting with the Code field through the Data
field. This field presents only if the I bit is set. The field
immediately follows the Data field without adding any padding octet
before or after itself. The checksum MUST be computed for each
fragment (including the case where the entire IKEv2 message is
carried in a single fragment) by using the same key (i.e., SK_ai or
SK_ar) that is used for computing the checksum for the IKEv2
Encrypted payload in the encapsulated IKEv2 message. The Integrity
Checksum Data field is omitted for other packets. To minimize DoS
attacks on fragmented packets, messages that are not protected
SHOULD NOT be fragmented. Note that IKE_SA_INIT messages are the
only ones that are not encrypted or integrity protected, however,
such messages are not likely to be fragmented since they do not
carry certificates.
The EAP Type for this EAP method is <TBD>.
7. Retransmission
Since EAP authenticators support a timer-based retransmission
mechanism for EAP Requests and EAP peers retransmit the last valid
EAP Response when receiving a duplicate EAP Request message, IKEv2
messages MUST NOT be retransmitted based on timers, when used as EAP
authentication method.
8. Key derivation
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The EAP-IKEv2 method described in this document generates session
keys. These session keys are used to establish an IKE-SA which
provides protection of subsequent EAP-IKEv2 payloads. To export a
session key as part of the EAP keying framework [AS+03] it is
required to derive additional session keys for usage with EAP (i.e.,
MSK, EMSK and IV). It is good cryptographic security practice to use
different keys for different "applications". Hence we suggest
reusing the key derivation function suggested in Section 2.17 of
[Kau03] to create keying material KEYMAT.
The key derivation function defined is KEYMAT = prf+(SK_d, Ni | Nr),
where Ni and Nr are the Nonces from the IKE_SA_INIT exchange.
According to [AS+03] the keying material of MSK, EMSK and IV have to
be at minimum 64, 64 and 64 octets long.
The produced keying material for MSK, EMSK and IV MUST be twice the
minimum size (i.e., 128 octets).
9. Error Handling
As described in the IKEv2 specification, there are many kinds of
errors that can occur during IKE processing (i.e., processing the
Data field of EAP-IKEv2 Request and Response messages) and detailed
processing rules. EAP-IKEv2 follows the error handling rules
specified in the IKEv2 specification for errors on the Data field of
EAP-IKEv2 messages, with the following additional rules:
o For an IKEv2 error that triggers an initiation of an IKEv2
exchange (i.e., an INFORMATIONAL exchange), an EAP-IKEv2 message
that contains the IKEv2 request that is generated for the IKEv2
exchange MUST be sent to the peering entity. In this case, the
EAP message that caused the IKEv2 error MUST be treated as a
valid EAP message.
o For an IKEv2 error for which the IKEv2 message that caused the
error is discarded without triggering an initiation of an IKEv2
exchange, the EAP message that carries the the erroneous IKEv2
message MUST be treated as an invalid EAP message and discarded
as if it were not received at EAP layer.
For an error occurred outside the Data field of EAP-IKEv2 messages,
including defragmentation failures, integrity check failures, errors
in Flag and Message Length fields, the EAP message that caused the
error MUST be treated as an invalid EAP message and discarded as if
it were not received at EAP layer.
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When the EAP-IKEv2 method runs on a backend EAP server, an
outstanding EAP Request is not retransmitted based on timer and thus
there is a possibility of EAP conversation stall when the EAP server
receives an invalid EAP Response. To avoid this, the EAP server MAY
retransmit the outstanding EAP Request in response to an invalid EAP
Response. Alternatively, the EAP server MAY send a new EAP Request
in response to an invalid EAP Response with assigning a new
Identifier and putting the last transmitted IKEv2 message in the
Data field.
10. Fast Resume
TLS provides the capability of resuming a session. This offers
primarily performance improvement for a new authentication and key
exchange protocol run. In order to resume a session two approaches
can be taken:
a) Generic approach
b) Method-specific approach
The idea of approach (a) is to
- force each EAP method to create an EAP SA. This SA is kept at the
EAP peer and the EAP server and is used for subsequent exchanges.
- built this functionality into EAP itself.
Approach (b) is already used by existing methods using TLS. Choosing
(b) does not require any changes to EAP itself since each EAP method
has to implement its own mechanism.
So far it has not been decided which approach should be suggested
for EAP. In any case it seems that a generic approach contains some
difficulties since EAP methods need to negotiate the necessary
parameters with are required to build the EAP SA (lifetime,
algorithms, identifiers, etc.). Furthermore, it is necessary to
cover error cases which happen if the wrong AAA server is selected
(due to failover or load balancing) and the EAP SA is not found.
For both cases it is necessary to establish to keep some state
information. An additional motivation for establishing state is the
ability to provide passive user identity confidentiality as
exercised in [AH03]. Subsequent protocol exchanges use a pseudonym
instead of the long-term user identity.
Additionally it is necessary to list some requirements for
establishing an EAP SA and for running a fast resume. For example,
does the fast resume exchange need to provide key agreement or key
transport functionality?
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Once the above-raised issues have been addressed in the EAP working
group a solution will be added to EAP-IKEv2.
11. Security Considerations
The security of the proposed EAP method is intentionally based on
IKEv2 [Kau03]. Man-in-the-middle attacks discovered in the context
of tunneled authentication protocols (see [AN03] and [PL+03]) are
applicable to IKEv2 if legacy authentication with EAP [RFC2284] is
used. To counter this threat IKEv2 provides a compound
authentication by including the EAP provided session key inside the
AUTH payload.
12. Open Issues
The following issues are still under consideration:
- Reducing the number of messages
The message flows given in this document finish with an EAP-Success
message. In some cases it might be possible to skip these messages.
Furthermore it is possible to omit the first exchange if the
identity can be learned by other means.
- Notifications
IKEv2 provides the concept of notifications to exchange messages at
any time (e.g., dead peer detection). It remains for further study
which of these messages are required for this EAP method.
- Roles of initiator and responder
Figure 4 shows the initiator starting the EAP-IKEv2 exchange.
However, there is also the possibility to have the EAP server to
start the exchange which saves roundtrips. It remains for further
study to analyze the resulting security properties.
13. Normative References
[RFC2284] L. Blunk and J. Vollbrecht: "PPP Extensible Authentication
Protocol (EAP)", RFC 2284, March 1998.
[Kau03] C. Kaufman: "Internet Key Exchange (IKEv2) Protocol",
internet draft, Internet Engineering Task Force, October 2003. Work
in progress.
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EAP-IKEv2 October 2003
[RFC2119] S. Bradner: "Key words for use in RFCs to Indicate
Requirement Levels", RFC 2119, Internet Engineering Task Force,
March 1997.
14. Informative References
[AN03] N. Asokan, V. Niemi, and K. Nyberg: "Man-in-the-middle in
tunnelled authentication", In the Proceedings of the 11th
International Workshop on Security Protocols, Cambridge, UK, April
2003. To be published in the Springer-Verlag LNCS series.
[PL+03] J. Puthenkulam, V. Lortz, A. Palekar, D. Simon, and B.
Aboba, "The compound authentication binding problem," internet
draft, Internet Engineering Task Force, 2003. Work in progress.
[RFC2409] Harkins, D., Carrel, D., "The Internet Key Exchange
(IKE)", RFC 2409, November 1998.
[Per03] R. Perlman: "Understanding IKEv2: Tutorial, and rationale
for decisions", internet draft, Internet Engineering Task Force,
2003. Work in progress.
[AS+03] B. Aboba, D. Simon and J. Arkko: " EAP Key Management
Framework", internet draft, Internet Engineering Task Force,
October, 2003. Work in progress.
[HS03] H. Haverinen, J. Salowey: "EAP SIM Authentication", internet
draft, Internet Engineering Task Force, 2003. Work in progress.
[PS+03] A. Palekar, D. Simon, G. Zorn and S. Josefsson: "Protected
EAP Protocol (PEAP)", internet draft, Internet Engineering Task
Force, March 2003. Work in progress.
[AH03] J. Arkko and H. Haverinen: "EAP AKA Authentication", internet
draft, Internet Engineering Task Force, June 2003. Work in
progress.
Acknowledgments
We would like to thank Bernard Aboba, Jari Arkko, Paoulo Pagliusi
and John Vollbrecht for their comments to this draft.
Additionally we would like to thank members of the PANA design team
(namely D. Forsberg and A. Yegin) for their comments and input to
the initial version of the draft.
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Finally we would like to thank the members of the EAP keying design
team for their discussion in the area of the EAP Key Management
Framework.
Author's Addresses
Hannes Tschofenig
Siemens AG
Otto-Hahn-Ring 6
81739 Munich
Germany
EMail: Hannes.Tschofenig@siemens.com
Dirk Kroeselberg
Siemens AG
Otto-Hahn-Ring 6
81739 Munich
Germany
EMail: Dirk.Kroeselberg@siemens.com
Yoshihiro Ohba
Toshiba America Research, Inc.
P.O. Box 136
Convent Station, NJ, 07961-0136
USA
Phone: +1 973 829 5174
Email: yohba@tari.toshiba.com
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EAP-IKEv2 October 2003
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