draft-ietf-stir-passport-shaken-08.txt   rfc8588.txt 
STIR C. Wendt Internet Engineering Task Force (IETF) C. Wendt
Internet-Draft Comcast Request for Comments: 8588 Comcast
Intended status: Standards Track M. Barnes Category: Standards Track M. Barnes
Expires: September 11, 2019 iconectiv ISSN: 2070-1721 iconectiv
March 10, 2019 May 2019
PASSporT SHAKEN Extension (SHAKEN) Personal Assertion Token (PaSSporT) Extension for Signature-based
draft-ietf-stir-passport-shaken-08 Handling of Asserted information using toKENs (SHAKEN)
Abstract Abstract
This document extends PASSporT, which is a token object that conveys This document extends the Personal Assertion Token (PASSporT), which
cryptographically-signed information about the participants involved is a token object that conveys cryptographically signed information
in communications. The extension is defined, corresponding to the about the participants involved in communications. The extension is
SHAKEN specification, to provide both a specific set of levels-of- defined based on the "Signature-based Handling of Asserted
confidence in the correctness of the originating identity for a SIP information using toKENs (SHAKEN)" specification by the ATIS/SIP
based Communication Service Provider (CSP) telephone network Forum IP-NNI Task Group. It provides both (1) a specific set of
originated call as well as an identifier that allows the CSP to levels of confidence in the correctness of the originating identity
uniquely identify the origin of the call within its network. of a call originated in a SIP-based telephone network as well as (2)
an identifier that allows the Service Provider (SP) to uniquely
identify the origin of the call within its network.
Status of This Memo Status of This Memo
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provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
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This Internet-Draft will expire on September 11, 2019. Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc8588.
Copyright Notice Copyright Notice
Copyright (c) 2019 IETF Trust and the persons identified as the Copyright (c) 2019 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Overview of 'shaken' PASSporT extension . . . . . . . . . . . 3 3. Overview of "shaken" PASSporT Extension . . . . . . . . . . 4
4. PASSporT 'attest' Claim . . . . . . . . . . . . . . . . . . . 4 4. PASSporT "attest" Claim . . . . . . . . . . . . . . . . . . . 4
5. PASSporT 'origid' Claim . . . . . . . . . . . . . . . . . . . 4 5. PASSporT "origid" Claim . . . . . . . . . . . . . . . . . . . 4
6. Example "shaken" PASSporT . . . . . . . . . . . . . . . . . . 4 6. Example "shaken" PASSporT . . . . . . . . . . . . . . . . . . 5
7. Using 'shaken' in SIP . . . . . . . . . . . . . . . . . . . . 4 7. Using "shaken" in SIP . . . . . . . . . . . . . . . . . . . . 5
8. Order of Claim Keys . . . . . . . . . . . . . . . . . . . . . 4 8. Order of Claim Keys . . . . . . . . . . . . . . . . . . . . . 5
9. Security Considerations . . . . . . . . . . . . . . . . . . . 5 9. Security Considerations . . . . . . . . . . . . . . . . . . . 6
10. Privacy Considerations . . . . . . . . . . . . . . . . . . . 5 10. Privacy Considerations . . . . . . . . . . . . . . . . . . . 6
11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
11.1. JSON Web Token claims . . . . . . . . . . . . . . . . . 6 11.1. JSON Web Token claims . . . . . . . . . . . . . . . . . 7
11.2. PASSporT Types . . . . . . . . . . . . . . . . . . . . . 6 11.2. PASSporT Types . . . . . . . . . . . . . . . . . . . . . 7
12. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 6 12. References . . . . . . . . . . . . . . . . . . . . . . . . . 7
13. References . . . . . . . . . . . . . . . . . . . . . . . . . 7 12.1. Normative References . . . . . . . . . . . . . . . . . . 7
13.1. Normative References . . . . . . . . . . . . . . . . . . 7 12.2. Informative References . . . . . . . . . . . . . . . . . 8
13.2. Informative References . . . . . . . . . . . . . . . . . 7 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 9
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 8 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9
1. Introduction 1. Introduction
The Signature-based Handling of Asserted information using toKENs The Signature-based Handling of Asserted information using toKENs
(SHAKEN) [ATIS-1000074] specification defines a framework for using (SHAKEN) [ATIS-1000074] specification defines a framework for using
Secure Telephone Identity Revisited (STIR) protocols including Secure Telephone Identity Revisited (STIR) protocols including the
PASSporT [RFC8225], SIP Authenticated Identity Management [RFC8224] Personal Assertion Token (PASSporT) [RFC8225], SIP Authenticated
and the STIR certificate framework [RFC8226] for implementing the Identity Management [RFC8224], and the STIR certificate framework
cryptographic validation of an authorized originator of telephone [RFC8226] for implementing the cryptographic validation of an
calls using SIP. Because the current telephone network contains both authorized originator of telephone calls using SIP. Because the
VoIP and TDM/SS7 originated traffic, there are many scenarios that current telephone network contains traffic originated from both VoIP
need to be accounted for where PASSporT signatures may represent and TDM/SS7 (Time Division Multiplexing / Signaling System 7), there
either direct or indirect call origination scenarios. The SHAKEN are many scenarios that need to be accounted for where PASSporT
[ATIS-1000074] specification defines levels of attestation of the signatures may represent either direct or indirect call origination
origination of the call as well as an origination identifier that can scenarios. The SHAKEN [ATIS-1000074] specification defines levels of
help create a unique association between the origin of a particular attestation of the origination of the call as well as an origination
call to the point in the VoIP or TDM telephone network the call came identifier that can help create a unique association between the
from to identify, for example, either a customer or class of service origin of a particular call to the point in the VoIP or TDM telephone
that call represents. This document specifies these values as claims network the call came from to identify, for example, either a
to extend the base set of PASSporT claims. customer or class of service that call represents. This document
specifies these values as claims to extend the base set of PASSporT
claims.
2. Terminology 2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP "OPTIONAL" in this document are to be interpreted as described in
14 [RFC2119] [RFC8174] when, and only when, they appear in all BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here. capitals, as shown here.
In addition, the following terms are used in this document: In addition, the following terms are used in this document:
o Verified association: is typically defined as an authenticated o Verified association: Typically defined as an authenticated
relationship between a customer and a device that initiated a call relationship between a customer and a device that initiated a call
on behalf of that customer, for example, a subscriber account with on behalf of that customer, for example, a subscriber account with
a specific SIM card or set of SIP credentials. a specific SIM card or set of SIP credentials.
o PASSporT: Defined in [RFC8225] is a JSON Web Token [RFC7519] o PASSporT: Defined in [RFC8225] is a JSON Web Token [RFC7519]
defined specifically for securing the identity of an initiator of defined specifically for securing the identity of an initiator of
personal communication. This document defines a specific personal communication. This document defines a specific
extension to PASSporT. extension to PASSporT.
3. Overview of 'shaken' PASSporT extension 3. Overview of "shaken" PASSporT Extension
The SHAKEN framework is designed to use PASSporT [RFC8225] as a The SHAKEN framework is designed to use PASSporT [RFC8225] as a
method of asserting the telephone number calling identity. In method of asserting the caller's telephone identity. In addition to
addition to the PASSporT base claims, there are two additional claims the PASSporT base claims, there are two additional claims that have
that have been defined for the needs of a service provider to signal been defined for the needs of a service provider to signal
information beyond just the telephone identity. First, in order to information beyond just the telephone identity. First, in order to
help bridge the transition of the state of the current telephone help bridge the transition of the state of the current telephone
network which has calls with no authentication and non-SIP [RFC3261] network (which has calls with no authentication and non-SIP [RFC3261]
signaling not compatible with the use of PASSporT and Secure signaling not compatible with the use of PASSporT and Secure
Telephone Identity (STI) in general, there is an attestation claim. Telephone Identity (STI) in general), there is an attestation claim.
This provides three levels of attestation, including a full This provides three levels of attestation: a full attestation when
attestation when the service provider can fully attest to the calling the service provider can fully attest to the calling identity, a
identity, a partial attestation, when the service provider originated partial attestation when the service provider originated a telephone
a telephone call but can not fully attest to the calling identity, call but cannot fully attest to the calling identity, and a gateway
and a gateway attestation which is the lowest level of attestation attestation, which is the lowest level of attestation and represents
and represents the service provider receiving a call from a non- the service provider receiving a call from a telephone gateway that
PASSporT and non-STI supporting telephone gateway. does not support PASSporT or STI.
The second claim is a unique origination identifier that should be The second claim is a unique origination identifier that should be
used by the service provider to identify different sources of used by the service provider to identify different sources of
telephone calls to support a traceback mechanism that can be used for telephone calls to support a traceback mechanism that can be used for
enforcement and identification of a source of illegitimate calls. enforcement and identification of a source of illegitimate calls.
The use of the compact form of PASSporT is not specified in this The use of the compact form of PASSporT is not specified in this
document and is not specified for use in SHAKEN [ATIS-1000074]. document and is not specified for use in SHAKEN [ATIS-1000074].
The next two sections define these new claims. The next two sections define these new claims.
4. PASSporT 'attest' Claim 4. PASSporT "attest" Claim
This indicator allows for both identifying the service provider that This indicator allows for both identifying the service provider that
is vouching for the call as well as clearly indicating what is vouching for the call as well as clearly indicating what
information the service provider is attesting to. The 'attest' claim information the service provider is attesting to. The "attest" claim
can be one of the following three values: 'A', 'B', or 'C'. These can be one of the following three values: 'A', 'B', or 'C'. These
values correspond to 'Full Attestation', 'Partial Attestation', and values correspond to 'Full Attestation', 'Partial Attestation', and
'Gateway Attestation', respectively. See [ATIS-1000074] for the 'Gateway Attestation', respectively. See [ATIS-1000074] for the
definitions of these three levels of attestation. definitions of these three levels of attestation.
5. PASSporT 'origid' Claim 5. PASSporT "origid" Claim
The purpose of the 'origid' claim is described in [ATIS-1000074]. The purpose of the "origid" claim is described in [ATIS-1000074].
The value of 'origid' claim is a UUID as defined in [RFC4122]. The value of "origid" claim is a Universally Unique Identifier (UUID)
Please refer to Section 10 for a discussion of the privacy as defined in [RFC4122]. Please refer to Section 10 for a discussion
considerations around the use of this value. of the privacy considerations around the use of this value.
6. Example "shaken" PASSporT 6. Example "shaken" PASSporT
Protected Header Protected Header
{ {
"alg":"ES256", "alg":"ES256",
"typ":"passport", "typ":"passport",
"ppt":"shaken", "ppt":"shaken",
"x5u":"https://cert.example.org/passport.cer" "x5u":"https://cert.example.org/passport.cer"
} }
Payload Payload
{ {
"attest":"A" "attest":"A"
"dest":{"tn":["12155550131"]} "dest":{"tn":["12155550131"]}
"iat":"1443208345", "iat":"1443208345",
"orig":{"tn":"12155550121"}, "orig":{"tn":"12155550121"},
"origid":"123e4567-e89b-12d3-a456-426655440000" "origid":"123e4567-e89b-12d3-a456-426655440000"
} }
7. Using 'shaken' in SIP 7. Using "shaken" in SIP
The use of the 'shaken' PASSporT type and the claims 'attest' and The use of the "shaken" PASSporT type and the "attest" and "origid"
'origid' are formally defined in [ATIS-1000074] for usage in SIP claims for SIP is formally defined in [ATIS-1000074] using the SIP
[RFC3261] aligned with the use of the identity header field defined [RFC3261] Identity header field defined in [RFC8224].
in [RFC8224].
8. Order of Claim Keys 8. Order of Claim Keys
The order of the claim keys MUST follow the rules of [RFC8225] The order of the claim keys MUST follow the rules of Section 9 of
Section 9; the claim keys MUST appear in lexicographic order. [RFC8225]; the claim keys MUST appear in lexicographic order.
Therefore, the claim keys discussed in this document appear in the Therefore, the claim keys discussed in this document appear in the
PASSporT Payload in the following order, PASSporT Payload in the following order:
o attest o attest
o dest o dest
o iat o iat
o orig o orig
o origid o origid
9. Security Considerations 9. Security Considerations
This document defines a new PASSporT [RFC8225] extension. The This document defines a new PASSporT [RFC8225] extension. The
considerations related to the security of the PASSporT object itself considerations related to the security of the PASSporT object itself
are the same as those described in [RFC8225]. are the same as those described in [RFC8225].
[RFC8224] defines how to compare the values of the "dest", "orig" and [RFC8224] defines how to compare the values of the "dest", "orig",
"iat" claims against fields in a SIP containing a PASSporT as part of and "iat" claims against fields in a SIP message containing a
validating that request. The values of the new "attest" and "origid" PASSporT as part of validating that request. The values of the new
claims added by this extension are not used in such a validation "attest" and "origid" claims added by this extension are not used in
step. They are not compared to fields in the SIP message. Instead, such a validation step. They are not compared to fields in the SIP
they simply carry additional information from the signer to the message. Instead, they simply carry additional information from the
consumer of the PASSport. This new information shares the same signer to the consumer of the PASSporT. This new information shares
integrity protection and non-repudiation properties as the base the same integrity protection and non-repudiation properties as the
claims in the PASSporT. base claims in the PASSporT.
10. Privacy Considerations 10. Privacy Considerations
As detailed in [RFC3261] Section 26, SIP messages inherently carry As detailed in Section 26 of [RFC3261], SIP messages inherently carry
identifying information of the caller and callee. The addition of identifying information of the caller and callee. The addition of
STIR cryptographically attests that the signing party vouches for the STIR cryptographically attests that the signing party vouches for the
information given about the callee, as is discussed in the Privacy information given about the callee, as is discussed in the Privacy
Considerations of [RFC8224]. Considerations of [RFC8224].
SHAKEN [ATIS-1000074] furthermore adds an 'origid' value to the STIR SHAKEN [ATIS-1000074] furthermore adds an "origid" value to the STIR
PASSporT, which is an opaque unique identifier representing an PASSporT, which is an opaque unique identifier representing an
element on the path of a given SIP request. This identifier is element on the path of a given SIP request. This identifier is
generated by an originating telephone service provider to identify generated by an originating telephone service provider to identify
where within their network (e.g. a gateway or particular service where within their network (e.g. a gateway or particular service
element) a call was initiated; 'origid' can facilitate forensic element) a call was initiated; "origid" can facilitate forensic
analysis of call origins when identifying and stopping bad actors analysis of call origins when identifying and stopping bad actors
trying to spoof identities or make fraudulent calls. trying to spoof identities or make fraudulent calls.
The opacity of the 'origid' claim value is intended to minimize The opacity of the "origid" claim value is intended to minimize
exposure of information about the origination of calls labelled with exposure of information about the origination of calls labeled with
an 'origid' value. It is therefore RECOMMENDED that implementations an "origid" value. It is therefore RECOMMENDED that implementations
generate a unique 'origid' value per call in such a way that only the generate a unique "origid" value per call in such a way that only the
generator of the 'origid' can determine when two 'origid' values generator of the "origid" can determine when two "origid" values
represent the same or different elements. If deployed systems represent the same or different elements. If deployed systems
instead use a common or related 'origid' for service elements in instead use a common or related "origid" for service elements in
their network, the potential for discovering patterns through their network, the potential for discovering patterns through
correlation of those calls exists. This could allow a recipient of correlation of those calls exists. This could allow a recipient of
calls to, for instance, learn that a set of callers are using a calls to, for instance, learn that a set of callers are using a
particular service or coming through a common gateway. It is particular service or coming through a common gateway. It is
expected that SHAKEN PASSporTs are shared only within an [RFC3324] expected that SHAKEN PASSporTs are shared only within an [RFC3324]
trust domain and will be stripped before calls exit that trust trust domain and will be stripped before calls exit that trust
domain, but this information still could be used by analytics on domain, but this information still could be used by analytics on
intermediary and terminating systems to reveal information that could intermediary and terminating systems to reveal information that could
include geographic location and even device-level information, include geographic location and even device-level information,
depending on how the 'origid' is generated. depending on how the "origid" is generated.
11. IANA Considerations 11. IANA Considerations
11.1. JSON Web Token claims 11.1. JSON Web Token claims
This specification requests that the IANA add two new claims to the IANA has added two new claims to the "JSON Web Token Claims" registry
JSON Web Token Claims registry as defined in [RFC7519]. as defined in [RFC7519].
Claim Name: "attest"
Claim Name: attest
Claim Description: Attestation level as defined in SHAKEN framework Claim Description: Attestation level as defined in SHAKEN framework
Change Controller: IESG Change Controller: IESG
Specification Document(s): RFC 8588
Specification Document(s): [RFCThis] Claim Name: origid
Claim Name: "origid"
Claim Description: Originating Identifier as defined in SHAKEN Claim Description: Originating Identifier as defined in SHAKEN
framework framework
Change Controller: IESG Change Controller: IESG
Specification Document(s): RFC 8588
Specification Document(s): [RFCThis]
11.2. PASSporT Types 11.2. PASSporT Types
This specification requests that the IANA add a new entry to the IANA has added a new entry in the "Personal Assertion Token
Personal Assertion Token (PASSporT) Extensions registry for the type (PASSporT) Extensions" registry for the type "shaken", which is
"shaken" which is specified in [RFCThis]. specified in this document.
12. Acknowledgements
The authors would like to thank those that helped review and
contribute to this document including specific contributions from Jon
Peterson, Russ Housley, Robert Sparks, and Andrew Jurczak. The
authors would like to acknowledge the work of the ATIS/SIP Forum IP-
NNI Task Force to develop the concepts behind this document.
13. References 12. References
13.1. Normative References 12.1. Normative References
[ATIS-1000074] [ATIS-1000074]
ATIS/SIP Forum IP-NNI Task Group, "Signature-based ATIS/SIP Forum IP-NNI Task Group, "Signature-based
Handling of Asserted information using toKENs (SHAKEN)", Handling of Asserted information using toKENs (SHAKEN)",
January 2017, <https://access.atis.org/apps/group_public/ January 2017, <https://access.atis.org/apps/group_public/
download.php/32237/ATIS-1000074.pdf>. download.php/32237/ATIS-1000074.pdf>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC4122] Leach, P., Mealling, M., and R. Salz, "A Universally [RFC4122] Leach, P., Mealling, M., and R. Salz, "A Universally
Unique IDentifier (UUID) URN Namespace", RFC 4122, Unique IDentifier (UUID) URN Namespace", RFC 4122,
DOI 10.17487/RFC4122, July 2005, DOI 10.17487/RFC4122, July 2005,
<https://www.rfc-editor.org/info/rfc4122>. <https://www.rfc-editor.org/info/rfc4122>.
[RFC7519] Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token [RFC7519] Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token
(JWT)", RFC 7519, DOI 10.17487/RFC7519, May 2015, (JWT)", RFC 7519, DOI 10.17487/RFC7519, May 2015,
<https://www.rfc-editor.org/info/rfc7519>. <https://www.rfc-editor.org/info/rfc7519>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8224] Peterson, J., Jennings, C., Rescorla, E., and C. Wendt, [RFC8224] Peterson, J., Jennings, C., Rescorla, E., and C. Wendt,
"Authenticated Identity Management in the Session "Authenticated Identity Management in the Session
Initiation Protocol (SIP)", RFC 8224, Initiation Protocol (SIP)", RFC 8224,
DOI 10.17487/RFC8224, February 2018, DOI 10.17487/RFC8224, February 2018,
<https://www.rfc-editor.org/info/rfc8224>. <https://www.rfc-editor.org/info/rfc8224>.
[RFC8225] Wendt, C. and J. Peterson, "PASSporT: Personal Assertion [RFC8225] Wendt, C. and J. Peterson, "PASSporT: Personal Assertion
Token", RFC 8225, DOI 10.17487/RFC8225, February 2018, Token", RFC 8225, DOI 10.17487/RFC8225, February 2018,
<https://www.rfc-editor.org/info/rfc8225>. <https://www.rfc-editor.org/info/rfc8225>.
[RFC8226] Peterson, J. and S. Turner, "Secure Telephone Identity [RFC8226] Peterson, J. and S. Turner, "Secure Telephone Identity
Credentials: Certificates", RFC 8226, Credentials: Certificates", RFC 8226,
DOI 10.17487/RFC8226, February 2018, DOI 10.17487/RFC8226, February 2018,
<https://www.rfc-editor.org/info/rfc8226>. <https://www.rfc-editor.org/info/rfc8226>.
13.2. Informative References 12.2. Informative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC3261] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, [RFC3261] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston,
A., Peterson, J., Sparks, R., Handley, M., and E. A., Peterson, J., Sparks, R., Handley, M., and E.
Schooler, "SIP: Session Initiation Protocol", RFC 3261, Schooler, "SIP: Session Initiation Protocol", RFC 3261,
DOI 10.17487/RFC3261, June 2002, DOI 10.17487/RFC3261, June 2002,
<https://www.rfc-editor.org/info/rfc3261>. <https://www.rfc-editor.org/info/rfc3261>.
[RFC3323] Peterson, J., "A Privacy Mechanism for the Session
Initiation Protocol (SIP)", RFC 3323,
DOI 10.17487/RFC3323, November 2002,
<https://www.rfc-editor.org/info/rfc3323>.
[RFC3324] Watson, M., "Short Term Requirements for Network Asserted [RFC3324] Watson, M., "Short Term Requirements for Network Asserted
Identity", RFC 3324, DOI 10.17487/RFC3324, November 2002, Identity", RFC 3324, DOI 10.17487/RFC3324, November 2002,
<https://www.rfc-editor.org/info/rfc3324>. <https://www.rfc-editor.org/info/rfc3324>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC Acknowledgements
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>. The authors would like to thank those that helped review and
contribute to this document including specific contributions from Jon
Peterson, Russ Housley, Robert Sparks, and Andrew Jurczak. The
authors would like to acknowledge the work of the ATIS/SIP Forum
IP-NNI Task Force to develop the concepts behind this document.
Authors' Addresses Authors' Addresses
Chris Wendt Chris Wendt
Comcast Comcast
One Comcast Center One Comcast Center
Philadelphia, PA 19103 Philadelphia, PA 19103
USA United States of America
Email: chris-ietf@chriswendt.net Email: chris-ietf@chriswendt.net
Mary Barnes Mary Barnes
iconectiv iconectiv
Email: mary.ietf.barnes@gmail.com Email: mary.ietf.barnes@gmail.com
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