Working Group Name                                          I. Hajjeh
Internet Draft                                             INEOVATION
                                                             M. Badra
                                                     LIMOS Laboratory
Intended status: Experimental                       December 13, 2007
Expires: June 2008



      Credential Protection Ciphersuites for Transport Layer Security
                draft-hajjeh-tls-identity-protection-02.txt


Status of this Memo

   By submitting this Internet-Draft, each author represents that any
   applicable patent or other IPR claims of which he or she is aware
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   This Internet-Draft will expire on June 13, 2007.

Copyright Notice

   Copyright (C) The IETF Trust (2007).

Abstract

   TLS defines several ciphersuites providing authentication, data
   protection and session key exchange between two communicating
   entities. Some of these ciphersuites are used for completely
   anonymous key exchange, in which neither party is authenticated.



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   However, they are vulnerable to man-in-the-middle attacks and are
   therefore deprecated.

   This document defines a set of ciphersuites to add client credential
   protection to the Transport Layer Security (TLS) protocol.

Table of Contents


   1. Introduction................................................2
   2. TLS credential protection overview..........................3
   3. CP_RSA Key Exchange Algorithm...............................5
   4. CP_DHE and CP_DH Key Exchange Algorithms....................6
   5. CP_ECDH and CP_ECDHE Key Exchange Algorithm.................6
   6. Security Considerations.....................................7
   7. IANA Considerations.........................................7
   8. References..................................................9
      8.1. Normative References...................................9
      8.2. Informative References.................................9
   Author's Addresses............................................10
   Intellectual Property Statement...............................10
   Disclaimer of Validity........................................10

1. Introduction

   TLS is the most deployed security protocol for securing exchanges. It
   provides end-to-end secure communications between two entities with
   authentication and data protection.

   TLS supports three authentication modes: authentication of both
   parties, only server-side authentication, and anonymous key exchange.
   For each mode, TLS specifies a set of ciphersuites. However,
   anonymous ciphersuites are strongly discouraged because they cannot
   prevent man-in-the-middle attacks.

   Client credential protection may be established by changing the order
   of the messages that the client sends after receiving ServerHelloDone
   [CORELLA]. This is done by sending the ChangeCipherSpec message
   before the Certificate and the CertificateVerify messages and after
   the ClientKeyExchange message. However, it requires a major change to
   TLS machine state as long as a new TLS version.

   Client credential protection may also be done through a DHE exchange
   before establishing an ordinary handshake with identity information
   [SSLTLS]. This wouldn't however be secure enough against active
   attackers, which will be able to disclose the client's credentials



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   and wouldn't be favorable for some environments (e.g. mobile), due to
   the additional cryptographic computations.

   Client credential protection may also be possible, assuming that the
   client permits renegotiation after the first server authentication
   [TLS]. However, this requires more cryptographic computations and
   augments significantly the number of rounds trips. In fact,
   renegotiation refers back to an asymmetric encryption/decryption and
   to a full previously certificate chain verified public key, whose
   chain was verified properly during the first handshake and stored in
   the client session context. In addition, computation overhead
   increases due to all second handshake messages encryption/decryption.
   Where for round trips, their number increases dramatically when small
   data packets are used to convey TLS messages. Furthermore, it is
   mandatory for the server to complete a first TLS handshake before it
   becomes able to confirm if the client has a certificate or not.

   Client credential protection may as well be realized by exchanging a
   TLS extension that negotiates the symmetric encryption algorithm to
   be used for client certificate encrypting/decrypting [EAPIP]. This
   solution may suffer from interoperability issues related to TLS
   Extensions, TLS 1.0 and TLS 1.1 implementations, as described in
   [INTEROP].

   This document defines a set of ciphersuites to add client credential
   protection to TLS protocol. Client credential protection is provided
   by symmetrically encrypting the client certificate with a key derived
   from the SecurityParameters.master_secret,
   SecurityParameters.server_random and
   SecurityParameters.client_random. The symmetric encryption algorithm
   is set to the cipher algorithm of the ServerHello.cipher_suite.

1.1. Conventions used in this document

   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 RFC-2119 [RFC2119].

2. TLS credential protection overview

   This document specifies a set of ciphersuites for TLS. These
   ciphersuites reuse existing key exchange algorithms that require
   based-certificates authentication, and reuse also existing MAC, and
   bloc ciphers algorithms from [TLS] and [TLSCTR], [TLSECC], [TLSAES]
   and [TLSCAM]. Their names include the text "CP" to refer to the
   client credential protection. An example is shown below.



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   CipherSuite                         Key Exchange   Cipher        Hash
   TLS_CP_RSA_EXPORT_WITH_RC4_40_MD5   RSA            RC4_40        MD5
   TLS_CP_DHE_DSS_WITH_AES_128_CBC_SHA DHE            AES_128_CBC   SHA

   If the client has not a certificate with a type appropriate for one
   of the supported cipher key exchange algorithms or if the client will
   not be able to send such a certificate, the client MUST NOT include
   any credential protection ciphersuite in the
   ClientHello.cipher_suites.

   If the server selects a ciphersuite with client credential
   protection, the server MUST request a certificate from the client.

   If the server selects one of the ciphersuites defined in this
   document, the client MUST encrypt the Certificate and the
   CertificateVerify messages using the symmetric algorithm selected by
   the server from the list in ClientHello.cipher_suites and a key
   derived from the SecurityParameters.master_secret. This key is the
   same key used to encrypt data written by the client.

   If a stream cipher encryption algorithm has been selected, the client
   symmetrically encrypts Certificate and CertificateVerify messages
   without any padding byte.

   If a block cipher encryption algorithm has been selected, the client
   uses an explicit IV and adds padding value to force the length of the
   plaintext to be an integral multiple of the block cipher's block
   length, as it is described in section 6.2.3.2 of [TLS].

   For DHE key exchange algorithm, the client always sends the
   ClientKeyExchange message conveying its ephemeral DH public key Yc.

   For ECDHE key exchange algorithm, the client always sends the
   ClientKeyExchange message conveying its ephemeral ECDH public key Yc.

   Current TLS specifications note that if the client certificate
   already contains a suitable DH or ECDH public key, then Yc is
   implicit and does not need to be sent again and consequently, the
   client key exchange message will be sent, but it MUST be empty.
   Implementations of this document MUST send ClientKeyExchange message
   but always carrying the client Yc, whatever the PublicValueEncoding
   is implicit or explicit. Note that it is possible to correlate
   sessions by the same client when DH or ECDH are in use.






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         Client                           Server

         ClientHello       -------->
                                          ServerHello
                                          Certificate
                                          ServerKeyExchange*
                           <--------      CertificateRequest
         {Certificate}
         ClientKeyExchange
         {CertificateVerify}
         ChangeCipherSpec
         Finished          -------->
                                          ChangeCipherSpec
                           <--------      Finished
         Application Data  <------->      Application Data

   * Indicates optional or situation-dependent messages that are not
   always sent.

   {} Indicates messages that are symmetrically encrypted.

   The ciphersuites in Section 3 (CP_RSA Key Exchange Algorithm) use RSA
   based certificates to mutually authenticate a RSA exchange with the
   client credential protection.

   The ciphersuites in Section 4 (CP_DHE and CP_DH Key Exchange
   Algorithm) use DHE_RSA, DH_RSA, DHE_DSS or DH_DSS to mutually
   authenticate a (Ephemeral) Diffie-Hellman exchange.

   The ciphersuites in Section 5 (CP_ECDH and CP_ECDHE Key Exchange
   Algorithms) use ECDH_ECDSA, ECDHE_ECDSA, ECDH_RSA or ECDHE_RSA to
   mutually authenticate a (Ephemeral) EC Diffie-Hellman exchange.

3. CP_RSA Key Exchange Algorithm

   This section defines additional ciphersuites that use RSA based
   certificates to authenticate a RSA exchange. These ciphersuites give
   client credential protection.

   CipherSuite                       Key Exchange  Cipher           Hash

   TLS_CP_RSA_EXPORT_WITH_RC4_40_MD5      RSA      RC4_40            MD5
   TLS_CP_RSA_WITH_RC4_128_MD5            RSA      RC4_128           MD5
   TLS_CP_RSA_WITH_RC4_128_SHA            RSA      RC4_128           SHA
   TLS_CP_RSA_EXPORT_WITH_RC2_CBC_40_MD5  RSA      RC2_CBC_40        MD5
   TLS_CP_RSA_WITH_IDEA_CBC_SHA           RSA      IDEA_CBC          SHA
   TLS_CP_RSA_EXPORT_WITH_DES40_CBC_SHA   RSA      DES40_CBC         SHA


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   TLS_CP_RSA_WITH_DES_CBC_SHA            RSA      DES_CBC           SHA
   TLS_CP_RSA_WITH_3DES_EDE_CBC_SHA       RSA      3DES_EDE          SHA
   TLS_CP_RSA_WITH_AES_128_CBC_SHA        RSA      AES_128_CBC       SHA
   TLS_CP_RSA_WITH_AES_256_CBC_SHA        RSA      AES_256_CBC       SHA
   TLS_CP_RSA_WITH_AES_128_CTR_SHA        RSA      AES_128_CTR       SHA
   TLS_CP_RSA_WITH_CAMELLIA_128_CBC_SHA   RSA      CAMELLIA_128_CBC  SHA
   TLS_CP_RSA_WITH_AES_256_CTR_SHA        RSA      AES_256_CTR       SHA
   TLS_CP_RSA_WITH_CAMELLIA_256_CBC_SHA   RSA      CAMELLIA_256_CBC  SHA

4. CP_DHE and CP_DH Key Exchange Algorithms

   This section defines additional ciphersuites that use DH and DHE as
   key exchange algorithms, with RSA or DSS based certificates to
   authenticate a (Ephemeral) Diffie-Hellman exchange. These
   ciphersuites give client credential protection.

   CipherSuite                      Key Exchange   Cipher           Hash

   TLS_CP_DHE_DSS_WITH_DES_CBC_SHA           DHE   DES_CBC           SHA
   TLS_CP_DHE_DSS_WITH_3DES_EDE_CBC_SHA      DHE   3DES_EDE_CBC      SHA
   TLS_CP_DHE_RSA_WITH_DES_CBC_SHA           DHE   DES_CBC           SHA
   TLS_CP_DHE_RSA_WITH_3DES_EDE_CBC_SHA      DHE   3DES_EDE_CBC      SHA
   TLS_CP_DHE_DSS_WITH_AES_128_CBC_SHA       DHE   AES_128_CBC       SHA
   TLS_CP_DHE_RSA_WITH_AES_128_CBC_SHA       DHE   AES_128_CBC       SHA
   TLS_CP_DHE_DSS_WITH_AES_256_CBC_SHA       DHE   AES_256_CBC       SHA
   TLS_CP_DHE_RSA_WITH_AES_256_CBC_SHA       DHE   AES_256_CBC       SHA
   TLS_CP_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA  DHE   CAMELLIA_128_CBC  SHA
   TLS_CP_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA  DHE   CAMELLIA_128_CBC  SHA
   TLS_CP_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA  DHE   CAMELLIA_256_CBC  SHA
   TLS_CP_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA  DHE   CAMELLIA_256_CBC  SHA
   TLS_CP_DHE_DSS_WITH_AES_128_CTR_SHA       DHE   AES_128_CTR       SHA
   TLS_CP_DHE_RSA_WITH_AES_128_CTR_SHA       DHE   AES_128_CTR       SHA
   TLS_CP_DHE_DSS_WITH_AES_256_CTR_SHA       DHE   AES_256_CTR       SHA
   TLS_CP_DHE_RSA_WITH_AES_256_CTR_SHA       DHE   AES_256_CTR       SHA
   TLS_CP_DH_DSS_WITH_DES_CBC_SHA            DH    DES_CBC           SHA
   TLS_CP_DH_DSS_WITH_3DES_EDE_CBC_SHA       DH    3DES_EDE_CBC      SHA
   TLS_CP_DH_RSA_WITH_DES_CBC_SHA            DH    DES_CBC           SHA
   TLS_CP_DH_RSA_WITH_3DES_EDE_CBC_SHA       DH    3DES_EDE_CBC      SHA
   TLS_CP_DH_DSS_WITH_AES_128_CBC_SHA        DH    AES_128_CBC       SHA
   TLS_CP_DH_RSA_WITH_AES_128_CBC_SHA        DH    AES_128_CBC       SHA
   TLS_CP_DH_DSS_WITH_AES_256_CBC_SHA        DH    AES_256_CBC       SHA
   TLS_CP_DH_RSA_WITH_AES_256_CBC_SHA        DH    AES_256_CBC       SHA

5. CP_ECDH and CP_ECDHE Key Exchange Algorithm

   This section defines additional ciphersuites that use ECDH and ECDHE
   as key exchange algorithms, with RSA or ECDSA based certificates to


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   authenticate a (Ephemeral) ECDH exchange. These ciphersuites give
   client credential protection.

   CipherSuite                         Key Exchange   Cipher        Hash

   TLS_CP_ECDH_ECDSA_WITH_RC4_128_SHA        ECDH     RC4_128        SHA
   TLS_CP_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA   ECDH     3DES_EDE_CBC   SHA
   TLS_CP_ECDH_ECDSA_WITH_AES_128_CBC_SHA    ECDH     AES_128_CBC    SHA
   TLS_CP_ECDH_ECDSA_WITH_AES_256_CBC_SHA    ECDHE    AES_256_CBC    SHA
   TLS_CP_ECDHE_ECDSA_WITH_RC4_128_SHA       ECDHE    RC4_128        SHA
   TLS_CP_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA  ECDHE    3DES_EDE_CBC   SHA
   TLS_CP_ECDHE_ECDSA_WITH_AES_128_CBC_SHA   ECDHE    AES_128_CBC    SHA
   TLS_CP_ECDHE_ECDSA_WITH_AES_256_CBC_SHA   ECDHE    AES_256_CBC    SHA
   TLS_CP_ECDH_RSA_WITH_RC4_128_SHA          ECDH     RC4_128        SHA
   TLS_CP_ECDH_RSA_WITH_3DES_EDE_CBC_SHA     ECDH     3DES_EDE_CBC   SHA
   TLS_CP_ECDH_RSA_WITH_AES_128_CBC_SHA      ECDH     AES_256_CBC    SHA
   TLS_CP_ECDH_RSA_WITH_AES_256_CBC_SHA      ECDH     AES_256_CBC    SHA
   TLS_CP_ECDHE_RSA_WITH_RC4_128_SHA         ECDHE    RC4_128        SHA
   TLS_CP_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA    ECDHE    3DES_EDE_CBC   SHA
   TLS_CP_ECDHE_RSA_WITH_AES_128_CBC_SHA     ECDHE    AES_256_CBC    SHA
   TLS_CP_ECDHE_RSA_WITH_AES_256_CBC_SHA     ECDHE    AES_256_CBC    SHA

6. Security Considerations

   The security considerations described throughout [TLS], [DTLS],
   [TLSAES], [TLSECC] and [TLSAES] apply here as well.

7. IANA Considerations

   This section provides guidance to the IANA regarding registration of
   values related to the credential protection ciphersuites.

   CipherSuite TLS_CP_RSA_EXPORT_WITH_RC4_40_MD5         ={ 0xXX,0xXX };
   CipherSuite TLS_CP_RSA_WITH_RC4_128_MD5               ={ 0xXX,0xXX };
   CipherSuite TLS_CP_RSA_WITH_RC4_128_SHA               ={ 0xXX,0xXX };
   CipherSuite TLS_CP_RSA_EXPORT_WITH_RC2_CBC_40_MD5     ={ 0xXX,0xXX };
   CipherSuite TLS_CP_RSA_WITH_IDEA_CBC_SHA              ={ 0xXX,0xXX };
   CipherSuite TLS_CP_RSA_EXPORT_WITH_DES40_CBC_SHA      ={ 0xXX,0xXX };
   CipherSuite TLS_CP_RSA_WITH_DES_CBC_SHA               ={ 0xXX,0xXX };
   CipherSuite TLS_CP_RSA_WITH_3DES_EDE_CBC_SHA          ={ 0xXX,0xXX };
   CipherSuite TLS_CP_RSA_WITH_AES_128_CBC_SHA           ={ 0xXX,0xXX };
   CipherSuite TLS_CP_RSA_WITH_AES_256_CBC_SHA           ={ 0xXX,0xXX };
   CipherSuite TLS_CP_RSA_WITH_AES_128_CTR_SHA           ={ 0xXX,0xXX };
   CipherSuite TLS_CP_RSA_WITH_CAMELLIA_128_CBC_SHA      ={ 0xXX,0xXX };
   CipherSuite TLS_CP_RSA_WITH_AES_256_CTR_SHA           ={ 0xXX,0xXX };
   CipherSuite TLS_CP_RSA_WITH_CAMELLIA_256_CBC_SHA      ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DHE_DSS_WITH_DES_CBC_SHA           ={ 0xXX,0xXX };


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   CipherSuite TLS_CP_DHE_DSS_WITH_3DES_EDE_CBC_SHA      ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DHE_RSA_WITH_DES_CBC_SHA           ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DHE_RSA_WITH_3DES_EDE_CBC_SHA      ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DHE_DSS_WITH_AES_128_CBC_SHA       ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DHE_RSA_WITH_AES_128_CBC_SHA       ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DHE_DSS_WITH_AES_256_CBC_SHA       ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DHE_RSA_WITH_AES_256_CBC_SHA       ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA  ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA  ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA  ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA  ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DHE_DSS_WITH_AES_128_CTR_SHA       ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DHE_RSA_WITH_AES_128_CTR_SHA       ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DHE_DSS_WITH_AES_256_CTR_SHA       ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DHE_RSA_WITH_AES_256_CTR_SHA       ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DH_DSS_WITH_DES_CBC_SHA            ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DH_DSS_WITH_3DES_EDE_CBC_SHA       ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DH_RSA_WITH_DES_CBC_SHA            ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DH_RSA_WITH_3DES_EDE_CBC_SHA       ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DH_DSS_WITH_AES_128_CBC_SHA        ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DH_RSA_WITH_AES_128_CBC_SHA        ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DH_DSS_WITH_AES_256_CBC_SHA        ={ 0xXX,0xXX };
   CipherSuite TLS_CP_DH_RSA_WITH_AES_256_CBC_SHA        ={ 0xXX,0xXX };
   CipherSuite TLS_CP_ECDH_ECDSA_WITH_RC4_128_SHA        ={ 0xXX,0xXX };
   CipherSuite TLS_CP_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA   ={ 0xXX,0xXX };
   CipherSuite TLS_CP_ECDH_ECDSA_WITH_AES_128_CBC_SHA    ={ 0xXX,0xXX };
   CipherSuite TLS_CP_ECDH_ECDSA_WITH_AES_256_CBC_SHA    ={ 0xXX,0xXX };
   CipherSuite TLS_CP_ECDHE_ECDSA_WITH_RC4_128_SHA       ={ 0xXX,0xXX };
   CipherSuite TLS_CP_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA  ={ 0xXX,0xXX };
   CipherSuite TLS_CP_ECDHE_ECDSA_WITH_AES_128_CBC_SHA   ={ 0xXX,0xXX };
   CipherSuite TLS_CP_ECDHE_ECDSA_WITH_AES_256_CBC_SHA   ={ 0xXX,0xXX };
   CipherSuite TLS_CP_ECDH_RSA_WITH_RC4_128_SHA          ={ 0xXX,0xXX };
   CipherSuite TLS_CP_ECDH_RSA_WITH_3DES_EDE_CBC_SHA     ={ 0xXX,0xXX };
   CipherSuite TLS_CP_ECDH_RSA_WITH_AES_128_CBC_SHA      ={ 0xXX,0xXX };
   CipherSuite TLS_CP_ECDH_RSA_WITH_AES_256_CBC_SHA      ={ 0xXX,0xXX };
   CipherSuite TLS_CP_ECDHE_RSA_WITH_RC4_128_SHA         ={ 0xXX,0xXX };
   CipherSuite TLS_CP_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA    ={ 0xXX,0xXX };
   CipherSuite TLS_CP_ECDHE_RSA_WITH_AES_128_CBC_SHA     ={ 0xXX,0xXX };
   CipherSuite TLS_CP_ECDHE_RSA_WITH_AES_256_CBC_SHA     ={ 0xXX,0xXX };

   Note: For implementation and deployment facilities, it is helpful to
   reserve a specific registry sub-range (minor, major) for credential
   protection ciphersuites.






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8. References

8.1. Normative References

   [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119, March 1997.

   [TLS]    Dierks, T. and E. Rescorla, "The TLS Protocol Version
             1.1", RFC 4346, April 2005.

   [DTLS]   Rescorla, E. and N. Modadugu, "Datagram Transport Layer
             Security", RFC 4347, April 2006.

   [TLSCAM]  Moriai, S., Kato, A., Kanda M., "Addition of Camellia
             Cipher Suites to Transport Layer Security (TLS)", RFC 4132,
             July 2005.

   [TLSAES]  Chown, P., "Advanced Encryption Standard (AES) Ciphersuites
             for Transport Layer Security (TLS)", RFC 3268, June 2002.

   [TLSECC]  Blake-Wilson, S., Bolyard, N., Gupta, V., Hawk, C.,
             Moeller, B., "Elliptic Curve Cryptography (ECC) Cipher
             Suites for Transport Layer Security (TLS)", RFC 4492, May
             2006

   [TLSCTR]  Modadugu, N. and E. Rescorla, "AES Counter Mode Cipher
             Suites for TLS and DTLS", draft-ietf-tls-ctr-01.txt
             (expired), June 2006.

8.2. Informative References

   [SSLTLS]  Rescorla, E., "SSL and TLS: Designing and Building Secure
             Systems", Addison-Wesley, March 2001.

   [CORELLA] Corella, F., "adding client identity protection to TLS",
             message on ietf-tls@lists.certicom.com mailing list,
             http://www.imc.org/ietf-tls/mail-archive/msg02004.html,
             August 2000.

   [INTEROP] Pettersen, Y., "Clientside interoperability experiences for
             the SSL and TLS protocols",draft-ietf-tls-interoperability-
             00 (expired), October 2006.

   [EAPIP]  Urien, P. and M. Badra, "Identity Protection within EAP-
             TLS", draft-urien-badra-eap-tls-identity-protection-01.txt
             (expired), October 2006.



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Author's Addresses

   Ibrahim Hajjeh
   INEOVATION
   France

   Email: hajjeh@ineovation.com


   Mohamad Badra
   LIMOS Laboratory - UMR6158, CNRS
   France

   Email: badra@isima.fr


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   THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
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Copyright Statement

   Copyright (C) The IETF Trust (2007).

   This document is subject to the rights, licenses and restrictions
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Acknowledgment

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