draft-ietf-mmusic-dtls-sdp-06.txt   draft-ietf-mmusic-dtls-sdp-07.txt 
Network Working Group C. Holmberg Network Working Group C. Holmberg
Internet-Draft Ericsson Internet-Draft Ericsson
Updates: 5763,7315 (if approved) R. Shpount Updates: 5763,7315 (if approved) R. Shpount
Intended status: Standards Track TurboBridge Intended status: Standards Track TurboBridge
Expires: August 8, 2016 February 5, 2016 Expires: August 24, 2016 February 21, 2016
Using the SDP Offer/Answer Mechanism for DTLS Using the SDP Offer/Answer Mechanism for DTLS
draft-ietf-mmusic-dtls-sdp-06.txt draft-ietf-mmusic-dtls-sdp-07.txt
Abstract Abstract
This draft defines the SDP offer/answer procedures for negotiating This draft defines the SDP offer/answer procedures for negotiating
and establishing a DTLS association. The draft also defines the and establishing a DTLS association. The draft also defines the
criteria for when a new DTLS association must be established. criteria for when a new DTLS association must be established.
This draft defines a new SDP media-level attribute, 'dtls- This draft defines a new SDP media-level attribute, 'dtls-
connection'. connection'.
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Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
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working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
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Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
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time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on August 8, 2016. This Internet-Draft will expire on August 24, 2016.
Copyright Notice Copyright Notice
Copyright (c) 2016 IETF Trust and the persons identified as the Copyright (c) 2016 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of (http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
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2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Establishing a new DTLS Association . . . . . . . . . . . . . 3 3. Establishing a new DTLS Association . . . . . . . . . . . . . 3
3.1. General . . . . . . . . . . . . . . . . . . . . . . . . . 3 3.1. General . . . . . . . . . . . . . . . . . . . . . . . . . 3
3.2. Change of Local Transport Parameters . . . . . . . . . . 3 3.2. Change of Local Transport Parameters . . . . . . . . . . 3
3.3. Change of ICE ufrag value . . . . . . . . . . . . . . . . 4 3.3. Change of ICE ufrag value . . . . . . . . . . . . . . . . 4
3.4. Multiple SDP fingerprint attributes . . . . . . . . . . . 4 3.4. Multiple SDP fingerprint attributes . . . . . . . . . . . 4
4. SDP dtls-connection Attribute . . . . . . . . . . . . . . . . 4 4. SDP dtls-connection Attribute . . . . . . . . . . . . . . . . 4
5. SDP Offer/Answer Procedures . . . . . . . . . . . . . . . . . 5 5. SDP Offer/Answer Procedures . . . . . . . . . . . . . . . . . 5
5.1. General . . . . . . . . . . . . . . . . . . . . . . . . . 5 5.1. General . . . . . . . . . . . . . . . . . . . . . . . . . 5
5.2. Generating the Initial SDP Offer . . . . . . . . . . . . 6 5.2. Generating the Initial SDP Offer . . . . . . . . . . . . 6
5.3. Generating the Answer . . . . . . . . . . . . . . . . . . 6 5.3. Generating the Answer . . . . . . . . . . . . . . . . . . 7
5.4. Offerer Processing of the SDP Answer . . . . . . . . . . 7 5.4. Offerer Processing of the SDP Answer . . . . . . . . . . 7
5.5. Modifying the Session . . . . . . . . . . . . . . . . . . 8 5.5. Modifying the Session . . . . . . . . . . . . . . . . . . 8
6. ICE Considerations . . . . . . . . . . . . . . . . . . . . . 8 6. ICE Considerations . . . . . . . . . . . . . . . . . . . . . 8
7. Transport Protocol Considerations . . . . . . . . . . . . . . 8 7. Transport Protocol Considerations . . . . . . . . . . . . . . 9
7.1. Transport Re-Usage . . . . . . . . . . . . . . . . . . . 9 7.1. Transport Re-Usage . . . . . . . . . . . . . . . . . . . 9
8. SIP Considerations . . . . . . . . . . . . . . . . . . . . . 9 8. SIP Considerations . . . . . . . . . . . . . . . . . . . . . 9
9. RFC Updates . . . . . . . . . . . . . . . . . . . . . . . . . 9 9. RFC Updates . . . . . . . . . . . . . . . . . . . . . . . . . 9
9.1. General . . . . . . . . . . . . . . . . . . . . . . . . . 9 9.1. General . . . . . . . . . . . . . . . . . . . . . . . . . 9
9.2. Update to RFC 5763 . . . . . . . . . . . . . . . . . . . 9 9.2. Update to RFC 5763 . . . . . . . . . . . . . . . . . . . 10
9.3. Update to RFC 7345 . . . . . . . . . . . . . . . . . . . 14 9.3. Update to RFC 7345 . . . . . . . . . . . . . . . . . . . 15
10. Security Considerations . . . . . . . . . . . . . . . . . . . 18 10. Security Considerations . . . . . . . . . . . . . . . . . . . 18
11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 18 11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 18
12. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 18 12. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 18
13. Change Log . . . . . . . . . . . . . . . . . . . . . . . . . 18 13. Change Log . . . . . . . . . . . . . . . . . . . . . . . . . 18
14. Normative References . . . . . . . . . . . . . . . . . . . . 20 14. References . . . . . . . . . . . . . . . . . . . . . . . . . 20
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 21 14.1. Normative References . . . . . . . . . . . . . . . . . . 20
14.2. Informative References . . . . . . . . . . . . . . . . . 21
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 22
1. Introduction 1. Introduction
[RFC5763] defines SDP Offer/Answer procedures for SRTP-DTLS. This [RFC5763] defines SDP Offer/Answer procedures for SRTP-DTLS. This
draft defines the SDP Offer/Answer [RFC3264] procedures for draft defines the SDP Offer/Answer [RFC3264] procedures for
negotiation DTLS in general, based on the procedures in [RFC5763]. negotiation DTLS in general, based on the procedures in [RFC5763].
This draft also defines a new SDP attribute, 'dtls-connection'. The
attribute is used in SDP offers and answers to explicitly indicate
whether a new DTLS association is to be established.
As defined in [RFC5763], a new DTLS association MUST be established As defined in [RFC5763], a new DTLS association MUST be established
when transport parameters are changed. Transport parameter change is when transport parameters are changed. Transport parameter change is
not well defined when Interactive Connectivity Establishment (ICE) not well defined when Interactive Connectivity Establishment (ICE)
[RFC5245] is used. One possible way to determine a transport change [RFC5245] is used. One possible way to determine a transport change
is based on ufrag change, but the ufrag value is changed both when is based on ufrag change, but the ufrag value is changed both when
ICE is negotiated and when ICE restart [RFC5245] occurs. These ICE is negotiated and when ICE restart [RFC5245] occurs. These
events do not always require a new DTLS association to be events do not always require a new DTLS association to be
established, but currently there is no way to explicitly indicate in established, but currently there is no way to explicitly indicate in
an SDP offer or answer whether a new DTLS association is required. an SDP offer or answer whether a new DTLS association is required.
To solve that problem, this draft defines a new SDP attribute, 'dtls- To solve that problem, this draft defines a new SDP attribute, 'dtls-
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o The fingerprint (certificate) value changes; or o The fingerprint (certificate) value changes; or
o The establishment of a new DTLS association is explicitly o The establishment of a new DTLS association is explicitly
signaled; signaled;
NOTE: The first two items list above are based on the procedures in NOTE: The first two items list above are based on the procedures in
[RFC5763]. This draft adds the support for explicit signaling. [RFC5763]. This draft adds the support for explicit signaling.
Whenever an entity determines, based on the criteria above, that a Whenever an entity determines, based on the criteria above, that a
new DTLS association is required, the entity MUST initiate an new DTLS association is required, the entity MUST initiate an
associated SDP offer/answer transaction, following to the procedures associated SDP offer/answer transaction, following the procedures in
in Section 5. Section 5.
The sections below describe typical cases where a new DTLS The sections below describe typical cases where a new DTLS
association needs to be established. association needs to be established.
3.2. Change of Local Transport Parameters 3.2. Change of Local Transport Parameters
If an endpoint modifies its local transport parameters (IP address If an endpoint modifies its local transport parameters (address and/
and/or port), and if the modification requires a new DTLS or port), and if the modification requires a new DTLS association,
association, the endpoint MUST either change its DTLS role, its the endpoint MUST change its DTLS role, change its fingerprint value,
fingerprint value and/or use the SDP 'dtls-connection' attribute with and/or use the SDP 'dtls-connection' attribute with a 'new' value
a 'new' value Section 4. Section 4.
If the underlying transport explicitly prohibits a DTLS association
to span multiple transports, the SDP 'dtls-connection' attribute MUST
be set to 'new' if the transport is changed. An example of such case
is when DTLS is carried over SCTP, as described in [RFC6083].
3.3. Change of ICE ufrag value 3.3. Change of ICE ufrag value
If an endpoint uses ICE, and modifies a local ufrag value, and if the If an endpoint uses ICE, and modifies a local ufrag value, and if the
modification requires a new DTLS association, the endpoint MUST modification requires a new DTLS association, the endpoint MUST
either change its DTLS role, its fingerprint value and/or use the SDP either change its DTLS role, its fingerprint value and/or use the SDP
'dtls-connection' attribute with a 'new' value Section 4. 'dtls-connection' attribute with a 'new' value Section 4.
3.4. Multiple SDP fingerprint attributes 3.4. Multiple SDP fingerprint attributes
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A 'dtls-connection' attribute value of 'new' indicates that a new A 'dtls-connection' attribute value of 'new' indicates that a new
DTLS association MUST be established. A 'dtls-connection' attribute DTLS association MUST be established. A 'dtls-connection' attribute
value of 'existing' indicates that a new DTLS association MUST NOT be value of 'existing' indicates that a new DTLS association MUST NOT be
established. established.
Unlike the SDP 'connection' attribute for TLS, there is no default Unlike the SDP 'connection' attribute for TLS, there is no default
value defined for the 'dtls-connection' attribute. Implementations value defined for the 'dtls-connection' attribute. Implementations
that wish to use the attribute MUST explicitly include it in SDP that wish to use the attribute MUST explicitly include it in SDP
offers and answers. If an offer or answer does not contain an offers and answers. If an offer or answer does not contain an
attribute, other means needs to be used in order for endpoints to attribute (this could happen if the offerer or answerer represents an
determine whether an offer or answer is associated with an event that existing implementation that has not been updated to support the
requires the DTLS association to be re-established. attribute defined in this specification), other means needs to be
used in order for endpoints to determine whether an offer or answer
is associated with an event that requires the DTLS association to be
re-established.
The mux category [I-D.ietf-mmusic-sdp-mux-attributes] for the 'dtls-
connection' attribute is 'IDENTICAL', which means that the attribute
value must be identical across all media descriptions being
multiplexed [I-D.ietf-mmusic-sdp-bundle-negotiation].
For RTP-based media, the 'dtls-connection' attribute apply to whole
associated media description. The attribute MUST NOT be defined per
source (using the SDP 'ssrc' attribute [RFC5576]).
The SDP Offer/Answer [RFC3264] procedures associated with the The SDP Offer/Answer [RFC3264] procedures associated with the
attribute are defined in Section 5 attribute are defined in Section 5
5. SDP Offer/Answer Procedures 5. SDP Offer/Answer Procedures
5.1. General 5.1. General
This section defines the generic SDP offer/answer procedures for This section defines the generic SDP offer/answer procedures for
negotiating a DTLS association. Additional procedures (e.g. negotiating a DTLS association. Additional procedures (e.g.
regarding usage of usage specific SDP attributes etc) for individual regarding usage of specific SDP attributes etc) for individual DTLS
DTLS usages (e.g. SRTP-DTLS) are outside the scope of this usages (e.g. SRTP-DTLS) are outside the scope of this specification,
specification, and needs to be specified in a usage specific and need to be specified in a usage specific specification.
specification.
NOTE: The procedures in this section are generalizations of NOTE: The procedures in this section are generalizations of
procedures first specified in SRTP-DTLS [RFC5763], with the addition procedures first specified in SRTP-DTLS [RFC5763], with the addition
of usage of the SDP 'dtls-connection' attribute. That document is of usage of the SDP 'dtls-connection' attribute. That document is
herein revised to make use of these new procedures. herein revised to make use of these new procedures.
The procedures in this section apply to an SDP media description The procedures in this section apply to an SDP media description
("m=" line) associated a DTLS-protected media/data stream. ("m=" line) associated a DTLS-protected media/data stream.
In order to negotiate a DTLS association, the following SDP In order to negotiate a DTLS association, the following SDP
attributes are used: attributes are used:
o The SDP 'setup' attribute, defined in [RFC4145], is used to o The SDP 'setup' attribute, defined in [RFC4145], is used to
negotiate the DTLS roles; negotiate the DTLS roles;
o The SDP 'fingerprint' attribute, defined in [RFC4572], is used to o The SDP 'fingerprint' attribute, defined in [RFC4572], is used to
provide the fingerprint value; and provide the fingerprint value; and
o The SDP 'dtls-connection' attribute, defined in this o The SDP 'dtls-connection' attribute, defined in this
specification, is used to explicitly indicate whether a new DTLS specification, is used to explicitly indicate whether a new DTLS
association is to be established or whether a previous association association is to be established or a previous association is to
is to be used. be used.
Endpoints MUST NOT use the SDP 'connection' attribute [RFC4145] when
negotiating a DTLS association.
The SDP 'connection' attribute MAY be used if the usage is associated This specification does not define the usage of the SDP 'connection'
with another protocol layer, e.g. SCTP or TCP, used together with attribute [RFC4145] for negotiating a DTLS connection. However, the
DTLS. attribute MAY be used if the DTLS connection is used together with
another protocol, e.g. SCTP or TCP, for which the usage of the
attribute has been defined.
Unlike for TCP and TLS connections, endpoints MUST NOT use the SDP Unlike for TCP and TLS connections, endpoints MUST NOT use the SDP
'setup' attribute 'holdconn' value when negotiating a DTLS 'setup' attribute 'holdconn' value when negotiating a DTLS
association. association.
Endpoints MUST support SHA-256 for generating and verifying the Endpoints MUST support SHA-256 for generating and verifying the
fingerprint value associated with the DTLS association. The use of fingerprint value associated with the DTLS association. The use of
SHA-256 is preferred. SHA-256 is preferred.
Endpoints MUST, at a minimum, support Endpoints MUST, at a minimum, support
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If the offerer inserts the SDP 'setup' attribute with an 'actpass' or If the offerer inserts the SDP 'setup' attribute with an 'actpass' or
'passive' value, the offerer MUST be prepared to receive a DTLS 'passive' value, the offerer MUST be prepared to receive a DTLS
ClientHello message (if a new DTLS association is established by the ClientHello message (if a new DTLS association is established by the
answerer) from the answerer before it receives the SDP answer. answerer) from the answerer before it receives the SDP answer.
5.3. Generating the Answer 5.3. Generating the Answer
If an answerer receives an offer that contains an SDP 'dtls- If an answerer receives an offer that contains an SDP 'dtls-
connection' attribute with a 'new' value, or if the answerer receives connection' attribute with a 'new' value, or if the answerer receives
and offer that contains an 'dtls-connection' attribute with an an offer that contains an 'dtls-connection' attribute with an
'existing' value and the answerer determines (based on the criteria 'existing' value and the answerer determines (based on the criteria
for establishing a new DTLS association) that a new DTLS association for establishing a new DTLS association) that a new DTLS association
is to be established, the answerer MUST insert a 'new' value in the is to be established, the answerer MUST insert a 'new' value in the
associated answer. In addition, the answerer MUST insert an SDP associated answer. In addition, the answerer MUST insert an SDP
'setup' attribute according to the procedures in [RFC4145], and an 'setup' attribute according to the procedures in [RFC4145], and an
SDP 'fingerprint' attribute according to the procedures in [RFC4572], SDP 'fingerprint' attribute according to the procedures in [RFC4572],
in the answer. in the answer.
If an answerer receives an offer that contains an SDP 'dtls- If an answerer receives an offer that contains an SDP 'dtls-
connection' attribute with a 'new' value, and if the answerer does connection' attribute with a 'new' value, and if the answerer does
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value that does not change the previously sent fingerprint, in the value that does not change the previously sent fingerprint, in the
answer. answer.
If the answerer receives an offer that does not contain an SDP 'dtls- If the answerer receives an offer that does not contain an SDP 'dtls-
connection' attribute, the answerer MUST NOT insert a 'dtls- connection' attribute, the answerer MUST NOT insert a 'dtls-
connection' attribute in the answer. connection' attribute in the answer.
If a new DTLS association is to be established, and if the answerer If a new DTLS association is to be established, and if the answerer
inserts an SDP 'setup' attribute with an 'active' value in the inserts an SDP 'setup' attribute with an 'active' value in the
answer, the answerer MUST initiate a DTLS handshake by sending a DTLS answer, the answerer MUST initiate a DTLS handshake by sending a DTLS
ClientHello message towards the the offerer. ClientHello message towards the offerer.
5.4. Offerer Processing of the SDP Answer 5.4. Offerer Processing of the SDP Answer
When an offerer receives an answer that contains an SDP 'dtls- When an offerer receives an answer that contains an SDP 'dtls-
connection' attribute with a 'new' value, and if the offerer becomes connection' attribute with a 'new' value, and if the offerer becomes
DTLS client (based on the value of the SDP 'setup' attribute value DTLS client (based on the value of the SDP 'setup' attribute value
[RFC4145]), the offerer MUST establish a DTLS association. If the [RFC4145]), the offerer MUST establish a DTLS association. If the
offerer becomes DTLS server, it MUST wait for the answerer to offerer becomes DTLS server, it MUST wait for the answerer to
establish the DTLS association. establish the DTLS association.
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[RFC3261] might be established between the caller and multiple [RFC3261] might be established between the caller and multiple
callees. This is referred to as forking. If forking occurs, callees. This is referred to as forking. If forking occurs,
separate DTLS associations MUST be established between the caller and separate DTLS associations MUST be established between the caller and
each callee. each callee.
It is possible to send an INVITE request which does not contain an It is possible to send an INVITE request which does not contain an
SDP offer. Such INVITE request is often referred to as an 'empty SDP offer. Such INVITE request is often referred to as an 'empty
INVITE', or an 'offerless INVITE'. The receiving endpoint will INVITE', or an 'offerless INVITE'. The receiving endpoint will
include the SDP offer in a response associated with the response. include the SDP offer in a response associated with the response.
When the endpoint generates such SDP offer, it MUST assign an SDP When the endpoint generates such SDP offer, it MUST assign an SDP
connection attribute, with a 'new' value, to each 'm-' line that 'dtls-connection' attribute, with a 'new' value, to each 'm-' line
describes DTLS protected media. If ICE is used, the endpoint MUST that describes DTLS protected media. If ICE is used, the endpoint
allocate a new set of ICE candidates, in order to ensure that two MUST allocate a new set of ICE candidates, in order to ensure that
DTLS association would not be running over the same transport. two DTLS association would not be running over the same transport.
9. RFC Updates 9. RFC Updates
9.1. General 9.1. General
This section updates specifications that use DTLS-protected media, in This section updates specifications that use DTLS-protected media, in
order to reflect the procedures defined in this specification. order to reflect the procedures defined in this specification.
9.2. Update to RFC 5763 9.2. Update to RFC 5763
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specification simply clarifies the procedures for negotiating and specification simply clarifies the procedures for negotiating and
establishing a DTLS association. establishing a DTLS association.
11. IANA Considerations 11. IANA Considerations
This document updates the "Session Description Protocol Parameters" This document updates the "Session Description Protocol Parameters"
registry as specified in Section 8.2.2 of [RFC4566]. Specifically, registry as specified in Section 8.2.2 of [RFC4566]. Specifically,
it adds the SDP dtls-connection attribute to the table for SDP media it adds the SDP dtls-connection attribute to the table for SDP media
level attributes. level attributes.
Attribute name: dtls-connection Attribute name: dtls-connection
Type of attribute: media-level Type of attribute: media-level
Subject to charset: no Subject to charset: no
Purpose: TBD Purpose: Indicate whether a new DTLS association is to be established/re-established.
Appropriate Values: see Section X Appropriate Values: see Section 4
Contact name: Christer Holmberg Contact name: Christer Holmberg
Category: IDENTICAL
12. Acknowledgements 12. Acknowledgements
Thanks to Justin Uberti, Martin Thomson, Paul Kyzivat and Jens Thanks to Justin Uberti, Martin Thomson, Paul Kyzivat and Jens
Guballa for providing comments and suggestions on the draft. Guballa for providing comments and suggestions on the draft.
13. Change Log 13. Change Log
[RFC EDITOR NOTE: Please remove this section when publishing] [RFC EDITOR NOTE: Please remove this section when publishing]
Changes from draft-ietf-mmusic-sdp-dtls-06
o Text on restrictions regarding spanning a DTLS connection over
multiple transports added.
o Mux category added to IANA Considerations.
o Normative text regarding mux category and source-specific
applicability added.
o Reference to RFC 7315 added.
o Clarified that offerer/answerer that has not been updated to
support this specification will not include the dtls-connection
attribute in offers and answers.
o Editorial corrections based on WGLC comments from Charles Eckel.
Changes from draft-ietf-mmusic-sdp-dtls-05 Changes from draft-ietf-mmusic-sdp-dtls-05
o Text on handling offer/answer error conditions added. o Text on handling offer/answer error conditions added.
Changes from draft-ietf-mmusic-sdp-dtls-04 Changes from draft-ietf-mmusic-sdp-dtls-04
o Editorial nits fixed based on comments from Paul Kyzivat: o Editorial nits fixed based on comments from Paul Kyzivat:
Changes from draft-ietf-mmusic-sdp-dtls-03 Changes from draft-ietf-mmusic-sdp-dtls-03
skipping to change at page 20, line 4 skipping to change at page 20, line 36
with another expired draft. with another expired draft.
o - Clarify that if ufrag in offer is unchanged, it must be o - Clarify that if ufrag in offer is unchanged, it must be
unchanged in associated answer. unchanged in associated answer.
o - SIP Considerations section added. o - SIP Considerations section added.
o - Section about multiple SDP fingerprint attributes added. o - Section about multiple SDP fingerprint attributes added.
Changes from draft-holmberg-mmusic-sdp-dtls-00 Changes from draft-holmberg-mmusic-sdp-dtls-00
o - Editorial changes and clarifications. o - Editorial changes and clarifications.
14. Normative References 14. References
14.1. Normative References
[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, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>. <http://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,
skipping to change at page 21, line 11 skipping to change at page 21, line 42
Traversal for Offer/Answer Protocols", RFC 5245, Traversal for Offer/Answer Protocols", RFC 5245,
DOI 10.17487/RFC5245, April 2010, DOI 10.17487/RFC5245, April 2010,
<http://www.rfc-editor.org/info/rfc5245>. <http://www.rfc-editor.org/info/rfc5245>.
[RFC5763] Fischl, J., Tschofenig, H., and E. Rescorla, "Framework [RFC5763] Fischl, J., Tschofenig, H., and E. Rescorla, "Framework
for Establishing a Secure Real-time Transport Protocol for Establishing a Secure Real-time Transport Protocol
(SRTP) Security Context Using Datagram Transport Layer (SRTP) Security Context Using Datagram Transport Layer
Security (DTLS)", RFC 5763, DOI 10.17487/RFC5763, May Security (DTLS)", RFC 5763, DOI 10.17487/RFC5763, May
2010, <http://www.rfc-editor.org/info/rfc5763>. 2010, <http://www.rfc-editor.org/info/rfc5763>.
[RFC7315] Jesske, R., Drage, K., and C. Holmberg, "Private Header
(P-Header) Extensions to the Session Initiation Protocol
(SIP) for the 3GPP", RFC 7315, DOI 10.17487/RFC7315, July
2014, <http://www.rfc-editor.org/info/rfc7315>.
14.2. Informative References
[RFC5576] Lennox, J., Ott, J., and T. Schierl, "Source-Specific
Media Attributes in the Session Description Protocol
(SDP)", RFC 5576, DOI 10.17487/RFC5576, June 2009,
<http://www.rfc-editor.org/info/rfc5576>.
[RFC6083] Tuexen, M., Seggelmann, R., and E. Rescorla, "Datagram
Transport Layer Security (DTLS) for Stream Control
Transmission Protocol (SCTP)", RFC 6083,
DOI 10.17487/RFC6083, January 2011,
<http://www.rfc-editor.org/info/rfc6083>.
[I-D.ietf-mmusic-sdp-mux-attributes]
Nandakumar, S., "A Framework for SDP Attributes when
Multiplexing", draft-ietf-mmusic-sdp-mux-attributes-12
(work in progress), January 2016.
[I-D.ietf-mmusic-sdp-bundle-negotiation]
Holmberg, C., Alvestrand, H., and C. Jennings,
"Negotiating Media Multiplexing Using the Session
Description Protocol (SDP)", draft-ietf-mmusic-sdp-bundle-
negotiation-25 (work in progress), January 2016.
Authors' Addresses Authors' Addresses
Christer Holmberg Christer Holmberg
Ericsson Ericsson
Hirsalantie 11 Hirsalantie 11
Jorvas 02420 Jorvas 02420
Finland Finland
Email: christer.holmberg@ericsson.com Email: christer.holmberg@ericsson.com
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