draft-ietf-tls-rsa-aes-gcm-03.txt   rfc5288.txt 
TLS Working Group J. Salowey Network Working Group J. Salowey
Internet-Draft A. Choudhury Request for Comments: 5288 A. Choudhury
Intended status: Standards Track D. McGrew Category: Standards Track D. McGrew
Expires: October 16, 2008 Cisco Systems, Inc. Cisco Systems, Inc.
April 14, 2008 August 2008
AES-GCM Cipher Suites for TLS
draft-ietf-tls-rsa-aes-gcm-03
Status of this Memo
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This Internet-Draft will expire on October 16, 2008. AES Galois Counter Mode (GCM) Cipher Suites for TLS
Copyright Notice Status of This Memo
Copyright (C) The IETF Trust (2008). This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Abstract Abstract
This memo describes the use of the Advanced Encryption Standard (AES) This memo describes the use of the Advanced Encryption Standard (AES)
in Galois/Counter Mode (GCM) as a Transport Layer Security (TLS) in Galois/Counter Mode (GCM) as a Transport Layer Security (TLS)
authenticated encryption operation. GCM provides both authenticated encryption operation. GCM provides both
confidentiality and data origin authentication, can be efficiently confidentiality and data origin authentication, can be efficiently
implemented in hardware for speeds of 10 gigabits per second and implemented in hardware for speeds of 10 gigabits per second and
above, and is also well-suited to software implementations. This above, and is also well-suited to software implementations. This
memo defines TLS cipher suites that use AES-GCM with RSA, DSS and memo defines TLS cipher suites that use AES-GCM with RSA, DSA, and
Diffie-Hellman based key exchange mechanisms. Diffie-Hellman-based key exchange mechanisms.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions Used in This Document . . . . . . . . . . . . . . . 2
2. Conventions Used In This Document . . . . . . . . . . . . . . . 3 3. AES-GCM Cipher Suites . . . . . . . . . . . . . . . . . . . . . 2
4. TLS Versions . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. AES-GCM Cipher Suites . . . . . . . . . . . . . . . . . . . . . 3 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 4
6. Security Considerations . . . . . . . . . . . . . . . . . . . . 4
4. TLS Versions . . . . . . . . . . . . . . . . . . . . . . . . . 4 6.1. Counter Reuse . . . . . . . . . . . . . . . . . . . . . . . 4
6.2. Recommendations for Multiple Encryption Processors . . . . 4
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 5 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 5
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 6
6. Security Considerations . . . . . . . . . . . . . . . . . . . . 5 8.1. Normative References . . . . . . . . . . . . . . . . . . . 6
6.1. Counter Reuse . . . . . . . . . . . . . . . . . . . . . . . 5 8.2. Informative References . . . . . . . . . . . . . . . . . . 6
6.2. Recommendations for Multiple Encryption Processors . . . . 5
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 6
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 7
8.1. Normative References . . . . . . . . . . . . . . . . . . . 7
8.2. Informative References . . . . . . . . . . . . . . . . . . 7
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 7
Intellectual Property and Copyright Statements . . . . . . . . . . 9
1. Introduction 1. Introduction
This document describes the use of AES [AES] in Galois Counter Mode This document describes the use of AES [AES] in Galois Counter Mode
(GCM) [GCM] (AES-GCM) with various key exchange mechanisms as a (GCM) [GCM] (AES-GCM) with various key exchange mechanisms as a
cipher suite for TLS. AES-GCM is an authenticated encryption with cipher suite for TLS. AES-GCM is an authenticated encryption with
associated data (AEAD) cipher (as defined in TLS 1.2 associated data (AEAD) cipher (as defined in TLS 1.2 [RFC5246])
[I-D.ietf-tls-rfc4346-bis]) providing both confidentiality and data providing both confidentiality and data origin authentication. The
origin authentication. The following sections define cipher suites following sections define cipher suites based on RSA, DSA, and
based on RSA, DSS and Diffie-Hellman key exchanges; ECC based cipher Diffie-Hellman key exchanges; ECC-based (Elliptic Curve Cryptography)
suites are defined in a separate document [I-D.ietf-tls-ecc-new-mac]. cipher suites are defined in a separate document [RFC5289].
AES-GCM is not only efficient and secure, but hardware AES-GCM is not only efficient and secure, but hardware
implementations can achieve high speeds with low cost and low implementations can achieve high speeds with low cost and low
latency, because the mode can be pipelined. Applications that latency, because the mode can be pipelined. Applications that
require high data throughput can benefit from these high-speed require high data throughput can benefit from these high-speed
implementations. AES-GCM has been specified as a mode that can be implementations. AES-GCM has been specified as a mode that can be
used with IPsec ESP [RFC4106] and 802.1AE MAC Security [IEEE8021AE]. used with IPsec ESP [RFC4106] and 802.1AE Media Access Control (MAC)
Security [IEEE8021AE].
2. Conventions Used In This Document 2. Conventions Used in This Document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. document are to be interpreted as described in [RFC2119].
3. AES-GCM Cipher Suites 3. AES-GCM Cipher Suites
The following cipher suites use the new authenticated encryption The following cipher suites use the new authenticated encryption
modes defined in TLS 1.2 with AES in Galois Counter Mode (GCM) [GCM]: modes defined in TLS 1.2 with AES in Galois Counter Mode (GCM) [GCM]:
CipherSuite TLS_RSA_WITH_AES_128_GCM_SHA256 = {TBD,TBD} CipherSuite TLS_RSA_WITH_AES_128_GCM_SHA256 = {0x00,0x9C}
CipherSuite TLS_RSA_WITH_AES_256_GCM_SHA384 = {TBD,TBD} CipherSuite TLS_RSA_WITH_AES_256_GCM_SHA384 = {0x00,0x9D}
CipherSuite TLS_DHE_RSA_WITH_AES_128_GCM_SHA256 = {TBD,TBD} CipherSuite TLS_DHE_RSA_WITH_AES_128_GCM_SHA256 = {0x00,0x9E}
CipherSuite TLS_DHE_RSA_WITH_AES_256_GCM_SHA384 = {TBD,TBD} CipherSuite TLS_DHE_RSA_WITH_AES_256_GCM_SHA384 = {0x00,0x9F}
CipherSuite TLS_DH_RSA_WITH_AES_128_GCM_SHA256 = {TBD,TBD} CipherSuite TLS_DH_RSA_WITH_AES_128_GCM_SHA256 = {0x00,0xA0}
CipherSuite TLS_DH_RSA_WITH_AES_256_GCM_SHA384 = {TBD,TBD} CipherSuite TLS_DH_RSA_WITH_AES_256_GCM_SHA384 = {0x00,0xA1}
CipherSuite TLS_DHE_DSS_WITH_AES_128_GCM_SHA256 = {TBD,TBD} CipherSuite TLS_DHE_DSS_WITH_AES_128_GCM_SHA256 = {0x00,0xA2}
CipherSuite TLS_DHE_DSS_WITH_AES_256_GCM_SHA384 = {TBD,TBD} CipherSuite TLS_DHE_DSS_WITH_AES_256_GCM_SHA384 = {0x00,0xA3}
CipherSuite TLS_DH_DSS_WITH_AES_128_GCM_SHA256 = {TBD,TBD} CipherSuite TLS_DH_DSS_WITH_AES_128_GCM_SHA256 = {0x00,0xA4}
CipherSuite TLS_DH_DSS_WITH_AES_256_GCM_SHA384 = {TBD,TBD} CipherSuite TLS_DH_DSS_WITH_AES_256_GCM_SHA384 = {0x00,0xA5}
CipherSuite TLS_DH_anon_WITH_AES_128_GCM_SHA256 = {TBD,TBD} CipherSuite TLS_DH_anon_WITH_AES_128_GCM_SHA256 = {0x00,0xA6}
CipherSuite TLS_DH_anon_WITH_AES_256_GCM_SHA384 = {TBD,TBD} CipherSuite TLS_DH_anon_WITH_AES_256_GCM_SHA384 = {0x00,0xA7}
These cipher suites use the AES-GCM authenticated encryption with These cipher suites use the AES-GCM authenticated encryption with
associated data (AEAD) algorithms AEAD_AES_128_GCM and associated data (AEAD) algorithms AEAD_AES_128_GCM and
AEAD_AES_256_GCM described in [RFC5116]. Note that each of these AEAD_AES_256_GCM described in [RFC5116]. Note that each of these
AEAD algorithms uses a 128-bit authentication tag with GCM. The AEAD algorithms uses a 128-bit authentication tag with GCM (in
"nonce" SHALL be 12 bytes long consisting of two parts as follows: particular, as described in Section 3.5 of [RFC4366], the
(this is an example of a "partially explicit" nonce; see section "truncated_hmac" extension does not have an effect on cipher suites
3.2.1 in [RFC5116]). that do not use HMAC). The "nonce" SHALL be 12 bytes long consisting
of two parts as follows: (this is an example of a "partially
explicit" nonce; see Section 3.2.1 in [RFC5116]).
struct{ struct{
opaque salt[4]; opaque salt[4];
opaque nonce_explicit[8]; opaque nonce_explicit[8];
} GCMNonce; } GCMNonce;
The salt is the "implicit" part of the nonce and is not sent in the The salt is the "implicit" part of the nonce and is not sent in the
packet. Instead the salt is generated as part of the handshake packet. Instead, the salt is generated as part of the handshake
process: it is either the client_write_IV (when the client is process: it is either the client_write_IV (when the client is
sending) or the server_write_IV (when the server is sending). The sending) or the server_write_IV (when the server is sending). The
salt length (SecurityParameters.fixed_iv_length) is 4 octets. salt length (SecurityParameters.fixed_iv_length) is 4 octets.
The nonce_explicit is the "explicit" part of the nonce. It is chosen The nonce_explicit is the "explicit" part of the nonce. It is chosen
by the sender and is carried in each TLS record in the by the sender and is carried in each TLS record in the
GenericAEADCipher.nonce_explicit field. The nonce_explicit length GenericAEADCipher.nonce_explicit field. The nonce_explicit length
(SecurityParameters.record_iv_length) is 8 octets. (SecurityParameters.record_iv_length) is 8 octets.
Each value of the nonce_explicit MUST be distinct for each distinct Each value of the nonce_explicit MUST be distinct for each distinct
invocation of GCM encrypt function for any fixed key. Failure to invocation of the GCM encrypt function for any fixed key. Failure to
meet this uniqueness requirement can significantly degrade security. meet this uniqueness requirement can significantly degrade security.
The nonce_explicit MAY be the 64-bit sequence number. The nonce_explicit MAY be the 64-bit sequence number.
The RSA, DHE_RSA, DH_RSA, DHE_DSS, DH_DSS, and DH_anon key exchanges The RSA, DHE_RSA, DH_RSA, DHE_DSS, DH_DSS, and DH_anon key exchanges
are performed as defined in [I-D.ietf-tls-rfc4346-bis]. are performed as defined in [RFC5246].
The PRF algorithms SHALL be as follows: The Pseudo Random Function (PRF) algorithms SHALL be as follows:
For cipher suites ending with _SHA256, the PRF is the TLS PRF For cipher suites ending with _SHA256, the PRF is the TLS PRF
[I-D.ietf-tls-rfc4346-bis] with SHA-256 as the hash function. [RFC5246] with SHA-256 as the hash function.
For cipher suites ending with _SHA384, the PRF is the TLS PRF For cipher suites ending with _SHA384, the PRF is the TLS PRF
[I-D.ietf-tls-rfc4346-bis] with SHA-384 as the hash function. [RFC5246] with SHA-384 as the hash function.
Implementations MUST send TLS Alert bad_record_mac for all types of Implementations MUST send TLS Alert bad_record_mac for all types of
failures encountered in processing the AES-GCM algorithm. failures encountered in processing the AES-GCM algorithm.
4. TLS Versions 4. TLS Versions
These cipher suites make use of the authenticated encryption with These cipher suites make use of the authenticated encryption with
additional data defined in TLS 1.2 [I-D.ietf-tls-rfc4346-bis]. They additional data defined in TLS 1.2 [RFC5246]. They MUST NOT be
MUST NOT be negotiated in older versions of TLS. Clients MUST NOT negotiated in older versions of TLS. Clients MUST NOT offer these
offer these cipher suites if they do not offer TLS 1.2 or later. cipher suites if they do not offer TLS 1.2 or later. Servers that
Servers which select an earlier version of TLS MUST NOT select one of select an earlier version of TLS MUST NOT select one of these cipher
these cipher suites. Because TLS has no way for the client to suites. Because TLS has no way for the client to indicate that it
indicate that it supports TLS 1.2 but not earlier, a non-compliant supports TLS 1.2 but not earlier, a non-compliant server might
server might potentially negotiate TLS 1.1 or earlier and select one potentially negotiate TLS 1.1 or earlier and select one of the cipher
of the cipher suites in this document. Clients MUST check the TLS suites in this document. Clients MUST check the TLS version and
version and generate a fatal "illegal_parameter" alert if they detect generate a fatal "illegal_parameter" alert if they detect an
an incorrect version. incorrect version.
5. IANA Considerations 5. IANA Considerations
IANA has assigned the following values for the cipher suites defined IANA has assigned the following values for the cipher suites defined
in this draft: in this document:
CipherSuite TLS_RSA_WITH_AES_128_GCM_SHA256 = {TBD,TBD} CipherSuite TLS_RSA_WITH_AES_128_GCM_SHA256 = {0x00,0x9C}
CipherSuite TLS_RSA_WITH_AES_256_GCM_SHA384 = {TBD,TBD} CipherSuite TLS_RSA_WITH_AES_256_GCM_SHA384 = {0x00,0x9D}
CipherSuite TLS_DHE_RSA_WITH_AES_128_GCM_SHA256 = {TBD,TBD} CipherSuite TLS_DHE_RSA_WITH_AES_128_GCM_SHA256 = {0x00,0x9E}
CipherSuite TLS_DHE_RSA_WITH_AES_256_GCM_SHA384 = {TBD,TBD} CipherSuite TLS_DHE_RSA_WITH_AES_256_GCM_SHA384 = {0x00,0x9F}
CipherSuite TLS_DH_RSA_WITH_AES_128_GCM_SHA256 = {TBD,TBD} CipherSuite TLS_DH_RSA_WITH_AES_128_GCM_SHA256 = {0x00,0xA0}
CipherSuite TLS_DH_RSA_WITH_AES_256_GCM_SHA384 = {TBD,TBD} CipherSuite TLS_DH_RSA_WITH_AES_256_GCM_SHA384 = {0x00,0xA1}
CipherSuite TLS_DHE_DSS_WITH_AES_128_GCM_SHA256 = {TBD,TBD} CipherSuite TLS_DHE_DSS_WITH_AES_128_GCM_SHA256 = {0x00,0xA2}
CipherSuite TLS_DHE_DSS_WITH_AES_256_GCM_SHA384 = {TBD,TBD} CipherSuite TLS_DHE_DSS_WITH_AES_256_GCM_SHA384 = {0x00,0xA3}
CipherSuite TLS_DH_DSS_WITH_AES_128_GCM_SHA256 = {TBD,TBD} CipherSuite TLS_DH_DSS_WITH_AES_128_GCM_SHA256 = {0x00,0xA4}
CipherSuite TLS_DH_DSS_WITH_AES_256_GCM_SHA384 = {TBD,TBD} CipherSuite TLS_DH_DSS_WITH_AES_256_GCM_SHA384 = {0x00,0xA5}
CipherSuite TLS_DH_anon_WITH_AES_128_GCM_SHA256 = {TBD,TBD} CipherSuite TLS_DH_anon_WITH_AES_128_GCM_SHA256 = {0x00,0xA6}
CipherSuite TLS_DH_anon_WITH_AES_256_GCM_SHA384 = {TBD,TBD} CipherSuite TLS_DH_anon_WITH_AES_256_GCM_SHA384 = {0x00,0xA7}
6. Security Considerations 6. Security Considerations
The security considerations in [I-D.ietf-tls-rfc4346-bis] apply to The security considerations in [RFC5246] apply to this document as
this document as well. The remainder of this section describes well. The remainder of this section describes security
security considerations specific to the cipher suites described in considerations specific to the cipher suites described in this
this document. document.
6.1. Counter Reuse 6.1. Counter Reuse
AES-GCM security requires that the counter is never reused. The IV AES-GCM security requires that the counter is never reused. The IV
construction in Section 3 is designed to prevent counter reuse. construction in Section 3 is designed to prevent counter reuse.
Implementers should also understand the practical considerations of
IV handling outlined in Section 9 of [GCM].
6.2. Recommendations for Multiple Encryption Processors 6.2. Recommendations for Multiple Encryption Processors
If multiple cryptographic processors are in use by the sender, then If multiple cryptographic processors are in use by the sender, then
the sender MUST ensure that, for a particular key, each value of the the sender MUST ensure that, for a particular key, each value of the
nonce_explicit used with that key is distinct. In this case each nonce_explicit used with that key is distinct. In this case, each
encryption processor SHOULD include in the nonce_explicit a fixed encryption processor SHOULD include, in the nonce_explicit, a fixed
value that is distinct for each processor. The recommended format is value that is distinct for each processor. The recommended format is
nonce_explicit = FixedDistinct || Variable nonce_explicit = FixedDistinct || Variable
where the FixedDistinct field is distinct for each encryption where the FixedDistinct field is distinct for each encryption
processor, but is fixed for a given processor, and the Variable field processor, but is fixed for a given processor, and the Variable field
is distinct for each distinct nonce used by a particular encryption is distinct for each distinct nonce used by a particular encryption
processor. When this method is used, the FixedDistinct fields used processor. When this method is used, the FixedDistinct fields used
by the different processors MUST have the same length. by the different processors MUST have the same length.
In the terms of Figure 2 in [RFC5116], the Salt is the Fixed-Common In the terms of Figure 2 in [RFC5116], the Salt is the Fixed-Common
part of the nonce (it is fixed, and it is common across all part of the nonce (it is fixed, and it is common across all
encryption processors), the FixedDistinct field exactly corresponds encryption processors), the FixedDistinct field exactly corresponds
to the Fixed-Distinct field, and the Variable field corresponds to to the Fixed-Distinct field, the Variable field corresponds to the
the Counter field, and the explicit part exactly corresponds to the Counter field, and the explicit part exactly corresponds to the
nonce_explicit. nonce_explicit.
For clarity, we provide an example for TLS in which there are two For clarity, we provide an example for TLS in which there are two
distinct encryption processors, each of which uses a one-byte distinct encryption processors, each of which uses a one-byte
FixedDistinct field: FixedDistinct field:
Salt = eedc68dc Salt = eedc68dc
FixedDistinct = 01 (for the first encryption processor) FixedDistinct = 01 (for the first encryption processor)
FixedDistinct = 02 (for the second encryption processor) FixedDistinct = 02 (for the second encryption processor)
skipping to change at page 6, line 47 skipping to change at page 5, line 47
GCMNonce nonce_explicit GCMNonce nonce_explicit
------------------------ ---------------------------- ------------------------ ----------------------------
eedc68dc0200000000000000 0200000000000000 eedc68dc0200000000000000 0200000000000000
eedc68dc0200000000000001 0200000000000001 eedc68dc0200000000000001 0200000000000001
eedc68dc0200000000000002 0200000000000002 eedc68dc0200000000000002 0200000000000002
... ...
7. Acknowledgements 7. Acknowledgements
This draft borrows heavily from [I-D.ietf-tls-ecc-new-mac]. The This document borrows heavily from [RFC5289]. The authors would like
authors would like to thank Alex Lam, Simon Josefsson and Pasi Eronen to thank Alex Lam, Simon Josefsson, and Pasi Eronen for providing
for providing useful comments during the review of this draft. useful comments during the review of this document.
8. References 8. References
8.1. Normative References 8.1. Normative References
[AES] National Institute of Standards and Technology, "Advanced [AES] National Institute of Standards and Technology,
Encryption Standard (AES)", FIPS 197, November 2001. "Advanced Encryption Standard (AES)", FIPS 197,
November 2001.
[GCM] Dworkin, M., "Recommendation for Block Cipher Modes of [GCM] Dworkin, M., "Recommendation for Block Cipher Modes of
Operation: Galois/Counter Mode (GCM) and GMAC", National Operation: Galois/Counter Mode (GCM) and GMAC",
Institute of Standards and Technology SP 800-38D, National Institute of Standards and Technology SP 800-
November 2007. 38D, November 2007.
[I-D.ietf-tls-rfc4346-bis]
Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", draft-ietf-tls-rfc4346-bis-10
(work in progress), March 2008.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC5116] McGrew, D., "An Interface and Algorithms for Authenticated [RFC5116] McGrew, D., "An Interface and Algorithms for
Encryption", RFC 5116, January 2008. Authenticated Encryption", RFC 5116, January 2008.
8.2. Informative References [RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer
Security (TLS) Protocol Version 1.2", RFC 5246,
August 2008.
[I-D.ietf-tls-ecc-new-mac] 8.2. Informative References
Rescorla, E., "TLS Elliptic Curve Cipher Suites with SHA-
256/384 and AES Galois Counter Mode",
draft-ietf-tls-ecc-new-mac-05 (work in progress),
April 2008.
[IEEE8021AE] [IEEE8021AE] Institute of Electrical and Electronics Engineers,
Institute of Electrical and Electronics Engineers, "Media "Media Access Control Security", IEEE Standard 802.1AE,
Access Control Security", IEEE Standard 802.1AE,
August 2006. August 2006.
[RFC4106] Viega, J. and D. McGrew, "The Use of Galois/Counter Mode [RFC4106] Viega, J. and D. McGrew, "The Use of Galois/Counter
(GCM) in IPsec Encapsulating Security Payload (ESP)", Mode (GCM) in IPsec Encapsulating Security Payload
RFC 4106, June 2005. (ESP)", RFC 4106, June 2005.
[RFC4366] Blake-Wilson, S., Nystrom, M., Hopwood, D., Mikkelsen,
J., and T. Wright, "Transport Layer Security (TLS)
Extensions", RFC 4366, April 2006.
[RFC5289] Rescorla, E., "TLS Elliptic Curve Cipher Suites with
SHA-256/384 and AES Galois Counter Mode", RFC 5289,
August 2008.
Authors' Addresses Authors' Addresses
Joseph Salowey Joseph Salowey
Cisco Systems, Inc. Cisco Systems, Inc.
2901 3rd. Ave 2901 3rd. Ave
Seattle, WA 98121 Seattle, WA 98121
USA USA
Email: jsalowey@cisco.com EMail: jsalowey@cisco.com
Abhijit Choudhury Abhijit Choudhury
Cisco Systems, Inc. Cisco Systems, Inc.
3625 Cisco Way 3625 Cisco Way
San Jose, CA 95134 San Jose, CA 95134
USA USA
Email: abhijitc@cisco.com EMail: abhijitc@cisco.com
David McGrew David McGrew
Cisco Systems, Inc. Cisco Systems, Inc.
170 W Tasman Drive 170 W Tasman Drive
San Jose, CA 95134 San Jose, CA 95134
USA USA
Email: mcgrew@cisco.com EMail: mcgrew@cisco.com
Full Copyright Statement Full Copyright Statement
Copyright (C) The IETF Trust (2008). Copyright (C) The IETF Trust (2008).
This document is subject to the rights, licenses and restrictions This document is subject to the rights, licenses and restrictions
contained in BCP 78, and except as set forth therein, the authors contained in BCP 78, and except as set forth therein, the authors
retain all their rights. retain all their rights.
This document and the information contained herein are provided on an This document and the information contained herein are provided on an
skipping to change at page 9, line 44 skipping to change at line 341
attempt made to obtain a general license or permission for the use of attempt made to obtain a general license or permission for the use of
such proprietary rights by implementers or users of this such proprietary rights by implementers or users of this
specification can be obtained from the IETF on-line IPR repository at specification can be obtained from the IETF on-line IPR repository at
http://www.ietf.org/ipr. http://www.ietf.org/ipr.
The IETF invites any interested party to bring to its attention any The IETF invites any interested party to bring to its attention any
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Acknowledgment
Funding for the RFC Editor function is provided by the IETF
Administrative Support Activity (IASA).
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