draft-ietf-sipping-nai-reqs-01.txt   draft-ietf-sipping-nai-reqs-02.txt 
Internet Draft Mark Watson SIP WG M. Watson
Document: draft-ietf-sipping-nai-reqs-01.txt Nortel Networks Internet-Draft Nortel Networks
Expires: December 9, 2002 June 10, 2002
Category: Informational
Expires November 2002 May 2002
Short term requirements for Network Asserted Identity Short Term Requirements for Network Asserted Identity
draft-ietf-sipping-nai-reqs-02.txt
Status of this Memo Status of this Memo
This document is an Internet-Draft and is in full conformance with This document is an Internet-Draft and is in full conformance with
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Copyright Notice
Copyright (C) The Internet Society (2002). All Rights Reserved.
Abstract Abstract
There is no requirement for identities asserted by a UA in a SIP
message to be anything other than the user's desired alias.
A Network Asserted Identity is an identity initially derived by a SIP A Network Asserted Identity is an identity initially derived by a SIP
network intermediary as a result of an authentication process. This network intermediary as a result of an authentication process. This
draft describes short term requirements for the exchange of Network draft describes short term requirements for the exchange of Network
Asserted Identities within networks of securely interconnected Asserted Identities within networks of securely interconnected
trusted nodes and to User Agents securely connected to such networks. trusted nodes and to User Agents securely connected to such networks.
Table of Contents Table of Contents
1. Introduction...................................................2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Definitions....................................................2 2. Definitions . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1 Identity...................................................2 2.1 Identity . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2 Network Asserted Identity..................................3 2.2 Network Asserted Identity . . . . . . . . . . . . . . . . . . 4
2.3 Trust Domains..............................................3 2.3 Trust Domains . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Generation of Network Asserted Identity........................5 2.4 Spec(T) . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4. Transport of Network Asserted Identity.........................5 3. Generation of Networks Asserted Identity . . . . . . . . . . . 7
4.1 Sending of Network Asserted Identity within a Trust Domain.5 4. Transport of Network Asserted Identity . . . . . . . . . . . . 7
4.2 Receiving of Network Asserted Identity withing a Trust Domain 4.1 Sending of Networks Asserted Identity within a Trust Domain . 7
...............................................................5 4.2 Receiving of Network Asserted Identity within a Trust Domain . 7
4.3 Sending of Network Asserted Identity to entities outside a 4.3 Sending of Network Asserted Identity to entities outside a
Trust Domain...................................................5 Trust Domain . . . . . . . . . . . . . . . . . . . . . . . . . 8
4.4 Receiving of Network Asserted Identity by a node outside the 4.4 Receiving of Network Asserted Identity by a node outside the
Trust Domain...................................................5 Trust Domain . . . . . . . . . . . . . . . . . . . . . . . . . 8
5. Parties with Network Asserted Identities.......................6 5. Parties with Network Asserted Identities . . . . . . . . . . . 8
6. Types of Network Asserted Identity.............................6 6. Types of Network Asserted Identity . . . . . . . . . . . . . . 8
7. Privacy of Network Asserted Identity...........................6 7. Privacy of Network Asserted Identity . . . . . . . . . . . . . 9
8. Next steps.....................................................7 8. Security Considerations . . . . . . . . . . . . . . . . . . . 9
9. Security considerations........................................7 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
10. IANA Considerations...........................................7 10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 10
11. References....................................................8 Normative References . . . . . . . . . . . . . . . . . . . . . 10
12. Acknowledgments...............................................8 Author's Address . . . . . . . . . . . . . . . . . . . . . . . 10
13. AuthorsÆ Addresses............................................8 Full Copyright Statement . . . . . . . . . . . . . . . . . . . 11
14. Full Copyright Statement......................................8
1. Introduction 1. Introduction
SIP [1] allows users to assert their identity in a number of ways SIP [1] allows users to assert their identity in a number of ways
e.g. using the From: header. However, there is no requirement for e.g. using the From: header. However, there is no requirement for
these identities to be anything other than the users desired alias. these identities to be anything other than the users desired alias.
An authenticated identity of a user can be obtained using SIP Digest An authenticated identity of a user can be obtained using SIP Digest
Authentication (or by other means). However, UAs do not always have Authentication (or by other means). However, UAs do not always have
the necessary key information to authenticate another UA. . the necessary key information to authenticate another UA.
A Network Asserted Identity is an identity initially derived by a SIP A Network Asserted Identity is an identity initially derived by a SIP
network intermediary as a result of an authentication process. This network intermediary as a result of an authentication process. This
may or may not be based on SIP Digest authentication. This draft may or may not be based on SIP Digest authentication. This draft
describes short term requirements for the exchange of Network describes short term requirements for the exchange of Network
Asserted Identities within networks of securely interconnected Asserted Identities within networks of securely interconnected
trusted nodes and also to User Agents with secure connections to such trusted nodes and also to User Agents with secure connections to such
networks. networks.
Such a network is described in this draft as a Trust Domain and we Such a network is described in this draft as a Trust Domain and we
skipping to change at page 3, line 4 skipping to change at page 3, line 35
purposes of this draft. These short-term requirements provide only purposes of this draft. These short-term requirements provide only
for the exchange of Network Asserted Identitied within a Trust Domain for the exchange of Network Asserted Identitied within a Trust Domain
and to an entity directly connected to the trust domain. and to an entity directly connected to the trust domain.
General requirements for transport of Network Asserted Identities on General requirements for transport of Network Asserted Identities on
the Internet are out of scope of this draft. the Internet are out of scope of this draft.
2. Definitions 2. Definitions
2.1 Identity 2.1 Identity
An Identity, for the purposes of this draft, is a URI, and optionally
a Display Name. The URI MUST be meaningful to the domain identified An Identity, for the purposes of this draft, is a sip:, sips: or tel:
in the URI when used as a SIP Request-URI. URI, and optionally a Display Name.
The URI MUST be meaningful to the domain identified in the URI (in
the case of sip: or sips: URIs) or the owner of the E.164 number (in
the case of tel: URIs), in the sense that when used as a SIP Request-
URI in a request sent to that domain/number range owner, it would
cause the request to be routed to the user/line that is associated
with the identity, or to be processed by service logic running on
that user's behalf.
If the URI is a sip: or sips: URI, then depending on the local policy If the URI is a sip: or sips: URI, then depending on the local policy
of the domain identified in the URI, the URI MAY identify some of the domain identified in the URI, the URI MAY identify some
specific entity, such as a person. specific entity, such as a person.
If the URI is a tel: URI, then depending on the local policy of the If the URI is a tel: URI, then depending on the local policy of the
owner of the number range within which the telephone number lies, the owner of the number range within which the telephone number lies, the
number MAY identify some specific entity, such as a telephone line. number MAY identify some specific entity, such as a telephone line.
However, it should be noted that identifying the owner of the number However, it should be noted that identifying the owner of the number
range is a less straightforward process than identifying the domain range is a less straightforward process than identifying the domain
which owns a sip: or sips: URI. which owns a sip: or sips: URI.
2.2 Network Asserted Identity 2.2 Network Asserted Identity
A Network Asserted Identity is an identity derived by a SIP network A Network Asserted Identity is an identity derived by a SIP network
entity as a result of an authentication process. entity as a result of an authentication process, which identifies the
authenticated entity in the sense defined in Section 2.1.
The authentication process used, or at least it's In the case of a sip: or sips: URI, the domain included in the URI
reliability/strength, is a known feature of the Trust Domain using MUST be within the Trust Domain.
the Network Asserted Identity mechanism i.e. in the language of 2.3
below, it is defined in Spec(T). In the case of a tel: URI, the owner of the E.164 number in the URI
MUST be within the Trust Domain.
The authentication process used, or at least it's reliability/
strength, is a known feature of the Trust Domain using the Network
Asserted Identity mechanism i.e. in the language of 2.3 below, it is
defined in Spec(T).
2.3 Trust Domains 2.3 Trust Domains
A Trust Domain for the purposes of Network Asserted Identity is a set A Trust Domain for the purposes of Network Asserted Identity is a set
of SIP nodes (UAC, UAS, proxies or other network intermediaries) that of SIP nodes (UAC, UAS, proxies or other network intermediaries) that
are trusted to exchange Network Asserted Identity information in the are trusted to exchange Network Asserted Identity information in the
sense described below. sense described below.
A node can be a member of a Trust Domain, T, only if the node is know A node can be a member of a Trust Domain, T, only if the node is know
to be compliant to a certain set of specifications, Spec(T), which to be compliant to a certain set of specifications, Spec(T), which
skipping to change at page 3, line 49 skipping to change at page 4, line 46
Trust Domain, T. Trust Domain, T.
Trust Domains are constructed by human beings who know the properties Trust Domains are constructed by human beings who know the properties
of the equipment they are using/deploying. In the simplest case, a of the equipment they are using/deploying. In the simplest case, a
Trust Domain is a set of devices with a single owner/operator who can Trust Domain is a set of devices with a single owner/operator who can
accurately know the behaviour of those devices. accurately know the behaviour of those devices.
Such simple Trust Domains may be joined into larger Trust Domains by Such simple Trust Domains may be joined into larger Trust Domains by
bi-lateral agreements between the owners/operators of the devices. bi-lateral agreements between the owners/operators of the devices.
We say a node is ætrustedÆ (with respect to a given Trust Domain) if We say a node is 'trusted' (with respect to a given Trust Domain) if
and only if it is a member of that domain. and only if it is a member of that domain.
We say that a node, A, in the domain is ætrusted byÆ a node, B, (or We say that a node, A, in the domain is 'trusted by' a node, B, (or
æB trusts AÆ) if and only if: 'B trusts A') if and only if:
(i) there is a secure connection between the nodes, AND 1. there is a secure connection between the nodes, AND
(ii) B has configuration information indicating that A is a member of
2. B has configuration information indicating that A is a member of
the Trust Domain. the Trust Domain.
Note that B may or may not be a member of the Trust Domain. For Note that B may or may not be a member of the Trust Domain. For
example, B may be a UA which trusts a given network intermediary, A example, B may be a UA which trusts a given network intermediary, A
(e.g. its home proxy). (e.g. its home proxy).
A æsecure connectionÆ in this context means that messages cannot be A 'secure connection' in this context means that messages cannot be
read by third parties, cannot be modified by third parties without read by third parties, cannot be modified by third parties without
detection and that B can be sure that the message really did come detection and that B can be sure that the message really did come
from A. The level of security required is a feature of the Trust from A. The level of security required is a feature of the Trust
Domain i.e. it is defined in Spec(T). Domain i.e. it is defined in Spec(T).
Within this context, SIP signaling information received by one node Within this context, SIP signaling information received by one node
FROM a node that it trusts is known to have been generated and passed FROM a node that it trusts is known to have been generated and passed
through the network according to the procedures of the particular through the network according to the procedures of the particular
specification set Spec(T), and therefore can be known to be valid, or specification set Spec(T), and therefore can be known to be valid, or
at least as valid as specified in the specifications Spec(T). at least as valid as specified in the specifications Spec(T).
Equally, a node can be sure that signaling information passed TO a Equally, a node can be sure that signaling information passed TO a
node that it trusts will be handled according to the procedures of node that it trusts will be handled according to the procedures of
Spec(T). Spec(T).
For these capabilities to be useful, Spec(T) must contain For these capabilities to be useful, Spec(T) must contain
requirements as to how the Network Asserted Identity is generated, requirements as to how the Network Asserted Identity is generated,
how its privacy is protected and how its integrity is maintained as how its privacy is protected and how its integrity is maintained as
it is passed around the network. A reader of Spec(T) can then make an it is passed around the network. A reader of Spec(T) can then make
informed judgement about the authenticity and reliability of Network an informed judgement about the authenticity and reliability of
Asserted Information received from the Trust Domain T. Network Asserted Information received from the Trust Domain T.
The term ætrustedÆ (with respect to a given Trust Domain) can be The term 'trusted' (with respect to a given Trust Domain) can be
applied to a given node in an absolute sense û it is just equivalent applied to a given node in an absolute sense - it is just equivalent
to saying the node is a member of the Trust Domain. However, the node to saying the node is a member of the Trust Domain. However, the
itself does not know whether another arbitrary node is ætrustedÆ, node itself does not know whether another arbitrary node is
even within the Trust Domain. It does know about certain nodes with 'trusted', even within the Trust Domain. It does know about certain
which it has secure connections as described above. nodes with which it has secure connections as described above.
With the definition above, statements such as æA trusted node SHALL With the definition above, statements such as 'A trusted node SHALL
...Æ are just shorthand for æA node compliant to this specification ...' are just shorthand for 'A node compliant to this specification
SHALL...Æ. SHALL...'.
Statements such as æWhen a node receives information from a trusted Statements such as 'When a node receives information from a trusted
node...Æ are NOT valid, because one node does not have complete node...' are NOT valid, because one node does not have complete
knowledge about all the other nodes in the trust domain. knowledge about all the other nodes in the trust domain.
Statements such as æWhen a node receives information from another Statements such as 'When a node receives information from another
node that it trusts...Æ ARE valid, and should be interpreted node that it trusts...' ARE valid, and should be interpreted
according to the criteria (i) and (ii) above. according to the criteria (1) and (2) above.
3. Generation of Network Asserted Identity The above relationships are illustrated in the following figure:
+------+
| |
| F |
| |
+------+
x
..............................x.........
. x .
. +------+ +------+ . +------+
. | | | | . | |
. | A | | B |-----.----| E |
. | | | | . | |
. +------+ +------+ . +------+
. \\ / .
. \\ +------+ // .
. \\ | | // .
. \ | C |/ .
. | | .
. +------+ .
. | Trust Domain.
........................................
|
|
|
+------+
| |
| D |
| |
+------+
xxxxxx Insecure connection
------ Secure connection
......
. .All boxes within the dotted line
......are part of the same Trust Domain
o A, B and C are part of the same trust domain
o A trusts C, but A does not trust B
o since E knows that B is inside of the trust domain, E
o trusts B, but B does not trust E
o B does not trust F, F does not trust B
2.4 Spec(T)
An aspect of the definition of a trust domain is that all the
elements in that domain are compliant to a set of configurations and
specifications generally referrred to as Spec(T). Spec(T) is not a
specification in the sense of a written document; rather, its an
agreed upon set of information that all elements are aware of.
Proper processing of the asserted identities requires that the
elements know what is actually being asserted, how it was determined,
and what the privacy policies are. All of that information is
characterized by Spec(T).
3. Generation of Networks Asserted Identity
A Network Asserted Identity is generated by a network intermediary A Network Asserted Identity is generated by a network intermediary
following an Authentication process which authenticates the entity following an Authentication process which authenticates the entity
(UA) to be identified. (UA) to be identified.
The Authentication process(es) used are a characteristic feature of The Authentication process(es) used are a characteristic feature of
the Trust Domain, and MUST be specified in Spec(T). the Trust Domain, and MUST be specified in Spec(T).
It shall be possible for a UA to provide a preferred identity to the It shall be possible for a UA to provide a preferred identity to the
network intermediary, which MAY be used to inform the generation of network intermediary, which MAY be used to inform the generation of
the Network Asserted Identity according to the policies of the Trust the Network Asserted Identity according to the policies of the Trust
Domain. Domain.
4. Transport of Network Asserted Identity 4. Transport of Network Asserted Identity
4.1 Sending of Network Asserted Identity within a Trust Domain 4.1 Sending of Networks Asserted Identity within a Trust Domain
It shall be possible for one node within a Trust Domain to securely It shall be possible for one node within a Trust Domain to securely
send a Network Asserted Identity to another node that it trusts. send a Network Asserted Identity to another node that it trusts.
4.2 Receiving of Network Asserted Identity withing a Trust Domain 4.2 Receiving of Network Asserted Identity within a Trust Domain
It shall be possible for one node within a Trust Domain to receive a It shall be possible for one node within a Trust Domain to receive a
Network Asserted identity from another node that it trusts. Network Asserted identity from another node that it trusts.
4.3 Sending of Network Asserted Identity to entities outside a Trust 4.3 Sending of Network Asserted Identity to entities outside a Trust
Domain Domain
If a node, A, within the Trust Domain, is trusted by a node, B, If a node, A, within the Trust Domain, is trusted by a node, B,
outside the Trust Domain, then it shall be possible for A to securely outside the Trust Domain, then it shall be possible for A to securely
send a Network Asserted Identity to B. send a Network Asserted Identity to B, if allowed by the privacy
policies of the user that has been identified, and the trust domain.
This is most often used to pass a Network Asserted Identity directly This is most often used to pass a Network Asserted Identity directly
to a UA. to a UA.
4.4 Receiving of Network Asserted Identity by a node outside the Trust 4.4 Receiving of Network Asserted Identity by a node outside the Trust
Domain Domain
It shall be possible for a node outside the Trust Domain to receive a It shall be possible for a node outside the Trust Domain to receive a
Network Asserted Identity from a node that it trusts. Network Asserted Identity from a node that it trusts.
Network Asserted Identity received in this way may be considered Network Asserted Identity received in this way may be considered
valid, and used for display to the user, input data for services etc. valid, and used for display to the user, input data for services etc.
Network Asserted Identity information received by one node from a Network Asserted Identity information received by one node from a
node which it does not trust carries no guarantee of authenticity or node which it does not trust carries no guarantee of authenticity or
integrity because it is not known that the procedures of Spec(T) were integrity because it is not known that the procedures of Spec(T) were
followed to generate and transport the information. Such information followed to generate and transport the information. Such information
MUST NOT be used. i.e. it shall not be displayed to the user, passed MUST NOT be used. i.e. it shall not be displayed to the user,
to other nodes, used as input data for services etc. passed to other nodes, used as input data for services etc.
5. Parties with Network Asserted Identities 5. Parties with Network Asserted Identities
A Network Asserted Identity identifies the originator of the message A Network Asserted Identity identifies the originator of the message
in which it was received. in which it was received.
For example, For example,
o a Network Asserted Identity received in an initial INVITE a Network Asserted Identity received in an initial INVITE (outside
(outside the context of any existing dialog) identifies the the context of any existing dialog) identifies the calling party.
calling party.
o a Network Asserted Identity received in a 180 Ringing response a Network Asserted Identity received in a 180 Ringing response to
to such an INVITE identifies the party who is ringing. such an INVITE identifies the party who is ringing.
o a Network Asserted Identity received in a 200 response to such a Network Asserted Identity received in a 200 response to such an
an INVITE identifies the party who has answered. INVITE identifies the party who has answered.
6. Types of Network Asserted Identity 6. Types of Network Asserted Identity
Each party shall have at most one Network Asserted Identity. It shall be possible to assert multiple identities associated with a
given party (in a given message), provided that these are of distinct
types. .
It shall be possible for the capability to transport multiple The types of identity supported shall be sip:, sips: and tel: URIs,
identities associated with a single party to be introduced in future. all of which identify the user as described in Section 2.1. It is
not required to transport both a sip: and sips: URI.
It shall be possible for the capability to transport additional types
of identity associated with a single party to be introduced in
future.
7. Privacy of Network Asserted Identity 7. Privacy of Network Asserted Identity
The means by which any privacy requirements in respect of the Network The means by which any privacy requirements in respect of the Network
Asserted Identity are determined are outside the scope of this draft. Asserted Identity are determined are outside the scope of this draft.
It shall be possible to indicate that a Network Asserted Identity is It shall be possible to indicate within a message containing a
Network Asserted Identity that this Network Asserted Identity is
subject to a privacy requirement which prevents it being passed to subject to a privacy requirement which prevents it being passed to
other users. other users. This indication should not carry any semantics as to
the reason for this privacy requirement.
It shall be possible to indicate that the user has requested that the It shall be possible to indicate that the user has requested that the
Network Asserted Identity be not passed to other users. Network Asserted Identity be not passed to other users. This is
distinct from the above indication, in that it implies specific user
intent with respect to the Network Asserted Identity.
The mechanism shall support Trust Domain policies where the above two The mechanism shall support Trust Domain policies where the above two
indications are equivalent, and policies where they are not. indications are equivalent (i.e. the only possible reason for a
privacy requirement is a request from the user), and policies where
they are not.
The Network Asserted Identity specification shall require that in the In this case, the Network Asserted Identity specification shall
case that the Network Asserted Identity cannot be passed to other require that the mechanism of Section 4.3 SHALL NOT be used i.e. a
users, the mechanism of 3.2 SHALL NOT be used i.e. a trusted node trusted node shall not pass the identity to a node it does not trust.
shall not pass the identity to a node it does not trust. However, the However, the mechanism of Section 4.3 MAY be used to transfer the
mechanism of 3.1 MAY be used to transfer the identity within the identity within the trusted network.
trusted network.
Note that æanonymityÆ requests from users or subscribers may well Note that 'anonymity' requests from users or subscribers may well
require functionality in addition to the above handling of Network require functionality in addition to the above handling of Network
Asserted Identities. Such additional functionality is out of the Asserted Identities. Such additional functionality is out of the
scope of this document. scope of this document.
8. Next steps 8. Security Considerations
It is has been agreed to adopt draft-jennings-sipping-nai-00 [2] as a
working group item to implement the requirements of this draft.
9. Security considerations
The requirements in this draft are NOT intended to result in a The requirements in this draft are NOT intended to result in a
mechanism with general applicability between arbitrary hosts on the mechanism with general applicability between arbitrary hosts on the
Internet. Internet.
Rather, the intention is to state requirements for a mechanism to be Rather, the intention is to state requirements for a mechanism to be
used within a community of devices which are known to obey the used within a community of devices which are known to obey the
specification of the mechanism (Spec(T)) and between which there are specification of the mechanism (Spec(T)) and between which there are
secure connections. Such a community is known here as a Trust Domain. secure connections. Such a community is known here as a Trust
Domain.
The requirements on the mechanisms used for security and to initially The requirements on the mechanisms used for security and to initially
derive the Network Asserted Identity must be part of the derive the Network Asserted Identity must be part of the
specification Spec(T). specification Spec(T).
Such devices may be hosts on the Internet.
The requirements also support the transfer of information from a node The requirements also support the transfer of information from a node
within the Trust Domain, via a secure connection to a node outside within the Trust Domain, via a secure connection to a node outside
the Trust Domain. the Trust Domain.
Use of this mechanism in any other context has serious security Use of this mechanism in any other context has serious security
shortcomings, namely that there is absolutely no guarantee that the shortcomings, namely that there is absolutely no guarantee that the
information has not been modified, or was even correct in the first information has not been modified, or was even correct in the first
place. place.
10. IANA Considerations 9. IANA Considerations
This document does not have any implications for IANA. This document does not have any implications for IANA.
11. References 10. Acknowledgments
[1] J. Rosenberg et al, ôSIP: Session initiation protocol," draft-
ietf-sip-rfc2543bis-09.txt, February 27th, 2002.
[2] C.Jennings, ôNetwork Asserted Identity headerö, draft-jennings- Thanks are due to Jon Peterson, Cullen Jennings, Allison Mankin and
sipping-nai-00, May 2002, work in progress. Jonathan Rosenburg for comments on this document.
12. Acknowledgments Normative References
Thanks are due to Jon Peterson, Cullen Jennings and Allison Mankin [1] Rosenberg, J. and H. Schulzrinne, "SIP: Session Initiation
for comments on this draft. Protocol", draft-ietf-sip-rfc2543bis-09 (work in progress),
February 2002.
13. AuthorsÆ Addresses Author's Address
Mark Watson Mark Watson
Nortel Networks (UK) Nortel Networks
Maidenhead Office Park (Bray House) Bray House
Maidenhead Office Park
Westacott Way Westacott Way
Maidenhead, Maidenhead, BERKS SL6 3QH
Berkshire Tel: +44 (0)1628-434456 UK
England Email: mwatson@nortelnetworks.com
14. Full Copyright Statement EMail: mwatson@nortelnetworks.com
Full Copyright Statement
Copyright (C) The Internet Society (2002). All Rights Reserved. Copyright (C) The Internet Society (2002). All Rights Reserved.
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and distributed, in whole or in part, without restriction of any and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other the copyright notice or references to the Internet Society or other
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developing Internet standards in which case the procedures for developing Internet standards in which case the procedures for
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EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT This document and the information contained herein is provided on an
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ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
PARTICULAR PURPOSE." BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
 End of changes. 

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