draft-ietf-mmusic-sctp-sdp-01.txt   draft-ietf-mmusic-sctp-sdp-02.txt 
MMUSIC S. Loreto MMUSIC S. Loreto
Internet-Draft G. Camarillo Internet-Draft G. Camarillo
Intended status: Standards Track Ericsson Intended status: Standards Track Ericsson
Expires: September 13, 2012 March 12, 2012 Expires: April 25, 2013 October 22, 2012
Stream Control Transmission Protocol (SCTP)-Based Media Transport in the Stream Control Transmission Protocol (SCTP)-Based Media Transport in the
Session Description Protocol (SDP) Session Description Protocol (SDP)
draft-ietf-mmusic-sctp-sdp-01 draft-ietf-mmusic-sctp-sdp-02
Abstract Abstract
SCTP (Stream Control Transmission Protocol) is a transport protocol SCTP (Stream Control Transmission Protocol) is a transport protocol
used to establish associations between two endpoints. This document used to establish associations between two endpoints. This document
describes how to express media transport over SCTP in SDP (Session describes how to express media transport over SCTP in SDP (Session
Description Protocol). This document defines the 'SCTP', 'SCTP/DTLS' Description Protocol). This document defines the 'SCTP', 'SCTP/DTLS'
and 'DTLS/SCTP' protocol identifiers for SDP. and 'DTLS/SCTP' protocol identifiers for SDP.
Status of this Memo Status of this Memo
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Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
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
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
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 September 13, 2012. This Internet-Draft will expire on April 25, 2013.
Copyright Notice Copyright Notice
Copyright (c) 2012 IETF Trust and the persons identified as the Copyright (c) 2012 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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to this document. Code Components extracted from this document must to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Protocol Identifier . . . . . . . . . . . . . . . . . . . . . 4 3. Protocol Identifier . . . . . . . . . . . . . . . . . . . . . 4
4. The Setup and Connection Attributes and Association 4. Media Formats . . . . . . . . . . . . . . . . . . . . . . . . 4
Management . . . . . . . . . . . . . . . . . . . . . . . . . . 4 4.1. data channels and m-line . . . . . . . . . . . . . . . . . 5
5. Multihoming . . . . . . . . . . . . . . . . . . . . . . . . . 5 5. Streams Attribute . . . . . . . . . . . . . . . . . . . . . . 6
6. Network Address Translation (NAT) Considerations . . . . . . . 5 6. Datachannel Attribute . . . . . . . . . . . . . . . . . . . . 6
7. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 7. The Setup and Connection Attributes and Association
7.1. Actpass/Passive . . . . . . . . . . . . . . . . . . . . . 6 Management . . . . . . . . . . . . . . . . . . . . . . . . . . 7
7.2. Existing Connection Reuse . . . . . . . . . . . . . . . . 7 8. Multihoming . . . . . . . . . . . . . . . . . . . . . . . . . 7
7.3. SDP description for DTLS Connection . . . . . . . . . . . 7 9. Network Address Translation (NAT) Considerations . . . . . . . 8
8. Security Considerations . . . . . . . . . . . . . . . . . . . 8 10. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 10.1. Actpass/Passive . . . . . . . . . . . . . . . . . . . . . 8
10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 8 10.2. Existing Connection Reuse . . . . . . . . . . . . . . . . 9
10.1. Normative References . . . . . . . . . . . . . . . . . . . 8 10.3. SDP description for DTLS Connection . . . . . . . . . . . 10
10.2. Informative References . . . . . . . . . . . . . . . . . . 9 11. Security Considerations . . . . . . . . . . . . . . . . . . . 10
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 10 12. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
13. References . . . . . . . . . . . . . . . . . . . . . . . . . . 11
13.1. Normative References . . . . . . . . . . . . . . . . . . . 11
13.2. Informative References . . . . . . . . . . . . . . . . . . 12
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 12
1. Introduction 1. Introduction
SDP (Session Description Protocol) [RFC4566] provides a general- SDP (Session Description Protocol) [RFC4566] provides a general-
purpose format for describing multimedia sessions in announcements or purpose format for describing multimedia sessions in announcements or
invitations. RFC4145 [RFC4145] specifies a general mechanism for invitations. RFC4145 [RFC4145] specifies a general mechanism for
describing and establishing TCP (Transmission Control Protocol) describing and establishing TCP (Transmission Control Protocol)
streams. RFC 4572 [RFC4572] extends RFC4145 [RFC4145] for describing streams. RFC 4572 [RFC4572] extends RFC4145 [RFC4145] for describing
TCP-based media streams that are protected using TLS (Transport Layer TCP-based media streams that are protected using TLS (Transport Layer
Security) [RFC5246]. Security) [RFC5246].
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3. Protocol Identifier 3. Protocol Identifier
The following is the format for an 'm' line, as specified in RFC4566 The following is the format for an 'm' line, as specified in RFC4566
[RFC4566]: [RFC4566]:
m=<media> <port> <proto> <fmt> ... m=<media> <port> <proto> <fmt> ...
This document defines three new values for the 'proto' field: 'SCTP', This document defines three new values for the 'proto' field: 'SCTP',
'SCTP/DTLS' and 'DTLS/SCTP'. 'SCTP/DTLS' and 'DTLS/SCTP'.
The 'SCTP' protocol identifier is similar to both the 'UDP' and 'TCP' The 'SCTP', 'SCTP/DTLS' and 'DTLS/SCTP' protocol identifiers are
protocol identifiers in that it only describes the transport protocol similar to both the 'UDP' and 'TCP' protocol identifiers in that they
and not the upper-layer protocol. Media described using an 'm' line only describe the transport protocol and not the upper-layer
containing the 'SCTP' protocol identifier are carried using SCTP protocol.
[RFC4960].
Media described using an 'm' line containing the 'SCTP' protocol
identifier are carried using SCTP [RFC4960].
The 'SCTP/DTLS' protocol identifier indicates that the media The 'SCTP/DTLS' protocol identifier indicates that the media
described will use the Datagram Transport Layer Security (DTLS) described will use the Datagram Transport Layer Security (DTLS)
[RFC4347] over SCTP as specified in [RFC6083]. [RFC4347] over SCTP as specified in [RFC6083].
The 'DTLS/SCTP' protocol identifier indicates that the media The 'DTLS/SCTP' protocol identifier indicates that the media
described will use SCTP on top of the Datagram Transport Layer described will use SCTP on top of the Datagram Transport Layer
Security (DTLS) protocol as specified in Security (DTLS) protocol as specified in
[I-D.tuexen-tsvwg-sctp-dtls-encaps]. [I-D.tuexen-tsvwg-sctp-dtls-encaps].
An 'm' line that specifies 'SCTP' or 'SCTP/DTLS' or 'DTLS/SCTP' MUST An 'm' line that specifies 'SCTP' or 'SCTP/DTLS' or 'DTLS/SCTP' MUST
further qualify the application-layer protocol using an fmt further qualify the application-layer protocol using an fmt
identifier. identifier.
An 'm' line that specifies 'SCTP/DTLS' or 'DTLS/SCTP' MUST further An 'm' line that specifies 'SCTP/DTLS' or 'DTLS/SCTP' MUST further
provide a certificate fingerprint. An SDP attribute (an 'a' line) is provide a certificate fingerprint. An SDP attribute (an 'a' line) is
used to transport and exchange end point certificate. The used to transport and exchange end point certificate. The
authentication certificates are interpreted and validated as defined authentication certificates are interpreted and validated as defined
in [RFC4572]. in [RFC4572].
4. The Setup and Connection Attributes and Association Management 4. Media Formats
The SDP specification, [RFC4566], states that specifications defining
new proto values, like the SCTP, SCTP/DTLS and DTLS/SCTP proto values
defined in this RFC, must define the rules by which their media
format (fmt) namespace is managed. Use of an existing MIME subtype
for the format is encouraged. If no MIME subtype exists, it is
RECOMMENDED that a suitable one is registered through the IETF
process [RFC4288] [RFC4289] by production of, or reference to, a
standards-track RFC that defines the transport protocol for the
format.
4.1. data channels and m-line
SCTP defines a stream as an unidirectional logical channel existing
within an SCTP association one to another SCTP endpoint. The streams
are used to provide the notion of in-sequence delivery. Each user
message is sent on a particular stream, either order or unordered.
Ordering is preserved only for all ordered messages sent on the same
stream.
A datachannel may be:
unidirectional: formed by one single incoming or outgoing SCTP
stream
bidirectional: a pair of one incoming stream and one outgoing SCTP
stream
Using the format part of the m line for negotiating datachannel
allows the intermediaries nodes to become aware of the kind of
traffic actually exchanged on each datachannel, as well as of the
number of datachannels established within the association.
If the <port> sub-field is 'SCTP' or 'SCTP/DTLS' or 'DTLS/SCTP' the
<fmt> sub-fields contain datachannel number identifiers. When a list
of datachannel number identifiers is given, this implies that all of
these datachannel MUST be used in the association. For the payload
type assignments the "a=datachannel:" attribute (see Section 6)
SHOULD be used to map from a datachannel number to a media encoding
name that identifies the payload format transported by the
datachannel.
[NOTE] The datachannel number identifier does not necessarily map
directly with the number of the stream used to form the channel.
[OPEN ISSUE 1]do we need a stream attribute for it?
[NOTE] The exact definition of datachannel depends from the actual
media type in use it can be a unidirectional channel formed by a
unidirectional stream of an SCTP association or a bidirectional
channel consisting of two SCTP streams one for each side of the
association.
[OPEN ISSUE 2] do we need to register the "RTCWeb" media type in
accordance with the requirements of RFC 4288 here or in the
Datachannel draft?.
[OPEN ISSUE 3] do we need also an attribute to specify the SCTP port
number for the SCTP over DTLS scenario? that can be useful in the
case where multiple association are running on top of the same DTLS
session.
An example of a datachannel payload type assignment is RTCWeb used
only in certain defined datachannel of the SCTP association.
m=application 54111 DTLS/SCTP 0 1 2
a=streams=3
a=datachannel:0 RTCWeb label=xxxx;options="dictionary string"
a=datachannel:1 RTCWeb label=xxxx;options="dictionary string"
a=datachannel:2 RTCWeb label=xxxx;options="dictionary string"
5. Streams Attribute
The 'streams' attribute indicates the number of streams to be
supported by the association. If this attribute is not present, the
implementation should provide a default, with a suggested value of
16.
streams-attr = "a=streams=" streamsnumbers
streamsnumbers = 1*DIGIT
6. Datachannel Attribute
This attribute maps from a datachannel number (as used in an "m="
line) to an encoding name denoting the payload format to be used.
datachannel-attr = "a=datachannel:" datachannel-number
datachannel-number = 1*DIGIT
7. The Setup and Connection Attributes and Association Management
The use of the 'setup' and 'connection' attributes in the context of The use of the 'setup' and 'connection' attributes in the context of
an SCTP association is identical to the use of these attributes in an SCTP association is identical to the use of these attributes in
the context of a TCP connection. That is, SCTP endpoints MUST follow the context of a TCP connection. That is, SCTP endpoints MUST follow
the rules in Sections 4 and 5 of RFC 4145 [RFC4145] when it comes to the rules in Sections 4 and 5 of RFC 4145 [RFC4145] when it comes to
the use of the 'setup' and 'connection' attributes in offer/answer the use of the 'setup' and 'connection' attributes in offer/answer
[RFC3264] exchanges. [RFC3264] exchanges.
The management of an SCTP association is identical to the management The management of an SCTP association is identical to the management
of a TCP connection. That is, SCTP endpoints MUST follow the rules of a TCP connection. That is, SCTP endpoints MUST follow the rules
in Section 6 of RFC 4145 [RFC4145] to manage SCTP associations. in Section 6 of RFC 4145 [RFC4145] to manage SCTP associations.
Whether to use the SCTP ordered or unordered delivery service is up Whether to use the SCTP ordered or unordered delivery service is up
to the applications using the SCTP association. to the applications using the SCTP association.
5. Multihoming 8. Multihoming
An SCTP endpoint, unlike a TCP endpoint, can be multihomed. An SCTP An SCTP endpoint, unlike a TCP endpoint, can be multihomed. An SCTP
endpoint is considered to be multihomed if it has more than one IP endpoint is considered to be multihomed if it has more than one IP
address. A multihomed SCTP endpoint informs a remote SCTP endpoint address. A multihomed SCTP endpoint informs a remote SCTP endpoint
about all its IP addresses using the address parameters of the INIT about all its IP addresses using the address parameters of the INIT
or the INIT-ACK chunk (depending on whether the multihomed endpoint or the INIT-ACK chunk (depending on whether the multihomed endpoint
is the one initiating the establishment of the association). is the one initiating the establishment of the association).
Therefore, once the address provided in the 'c' line has been used to Therefore, once the address provided in the 'c' line has been used to
establish the SCTP association (i.e., to send the INIT chunk), establish the SCTP association (i.e., to send the INIT chunk),
address management is performed using SCTP. This means that two SCTP address management is performed using SCTP. This means that two SCTP
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In such network environments, the SCTP endpoints can only exchange In such network environments, the SCTP endpoints can only exchange
media using the IP addresses listed in their 'c' lines. In these media using the IP addresses listed in their 'c' lines. In these
environments, an endpoint wishing to use a different address needs to environments, an endpoint wishing to use a different address needs to
update its 'c' line (e.g., by sending a re-INVITE with a new offer) update its 'c' line (e.g., by sending a re-INVITE with a new offer)
so that it contains the new IP address. so that it contains the new IP address.
It is worth to underline that when using SCTP on top of DTLS, only It is worth to underline that when using SCTP on top of DTLS, only
single homed SCTP associations can be used, since DTLS does not single homed SCTP associations can be used, since DTLS does not
expose any address management to its upper layer. expose any address management to its upper layer.
6. Network Address Translation (NAT) Considerations 9. Network Address Translation (NAT) Considerations
SCTP specific features (not present in UDP/TCP), such as the checksum SCTP specific features (not present in UDP/TCP), such as the checksum
(CRC32c) value calculated on the whole packet (not just the header) (CRC32c) value calculated on the whole packet (not just the header)
or its multihoming capabilities, present new challenges for NAT or its multihoming capabilities, present new challenges for NAT
traversal. [I-D.ietf-behave-sctpnat] describes an SCTP specific traversal. [I-D.ietf-behave-sctpnat] describes an SCTP specific
variant of NAT, which provides similar features of Network Address variant of NAT, which provides similar features of Network Address
and Port Translation (NAPT). and Port Translation (NAPT).
Current NATs do not typically support SCTP. As an alternative to Current NATs do not typically support SCTP. As an alternative to
design SCTP specific NATs, Encapsulating SCTP into UDP design SCTP specific NATs, Encapsulating SCTP into UDP
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At the time of writing, the work on NAT traversal for SCTP is still At the time of writing, the work on NAT traversal for SCTP is still
work in progress. Additionally, no extension has been defined to work in progress. Additionally, no extension has been defined to
integrate ICE (Interactive Connectivity Establishment) [RFC5768] with integrate ICE (Interactive Connectivity Establishment) [RFC5768] with
SCTP and its multihoming capabilities either. Therefore, this SCTP and its multihoming capabilities either. Therefore, this
specification does not define how to describe SCTP-over-UDP streams specification does not define how to describe SCTP-over-UDP streams
in SDP or how to establish and maintain SCTP associations using ICE. in SDP or how to establish and maintain SCTP associations using ICE.
Should these features be specified for SCTP in the future, there will Should these features be specified for SCTP in the future, there will
be a need to specify how to use them in an SDP environment as well. be a need to specify how to use them in an SDP environment as well.
7. Examples 10. Examples
The following examples show the use of the 'setup' and 'connection' The following examples show the use of the 'setup' and 'connection'
SDP attributes. As discussed in Section 4, the use of these SDP attributes. As discussed in Section 7, the use of these
attributes with an SCTP association is identical to their use with a attributes with an SCTP association is identical to their use with a
TCP connection. For the purpose of brevity, the main portion of the TCP connection. For the purpose of brevity, the main portion of the
session description is omitted in the examples, which only show 'm' session description is omitted in the examples, which only show 'm'
lines and their attributes (including 'c' lines). lines and their attributes (including 'c' lines).
7.1. Actpass/Passive 10.1. Actpass/Passive
An offerer at 192.0.2.2 signals its availability for an SCTP An offerer at 192.0.2.2 signals its availability for an SCTP
association at SCTP port 54111. Additionally, this offerer is also association at SCTP port 54111. Additionally, this offerer is also
willing to initiate the SCTP association: willing to initiate the SCTP association:
m=image 54111 SCTP * m=application 54111 SCTP 0 1 2
c=IN IP4 192.0.2.2 c=IN IP4 192.0.2.2
a=setup:actpass a=setup:actpass
a=connection:new a=connection:new
a=streams=3
a=datachannel:0 RTCWeb label=xxxx;options="dictionary string"
a=datachannel:1 RTCWeb label=xxxx;options="dictionary string"
a=datachannel:2 RTCWeb label=xxxx;options="dictionary string"
Figure 1 Figure 1
The endpoint at 192.0.2.1 responds with the following description: The endpoint at 192.0.2.1 responds with the following description:
m=image 54321 SCTP * m=image 54321 SCTP 0 1 2
c=IN IP4 192.0.2.1 c=IN IP4 192.0.2.1
a=setup:passive a=setup:passive
a=connection:new a=connection:new
a=streams=3
a=datachannel:0 RTCWeb label=xxxx;options="dictionary string"
a=datachannel:1 RTCWeb label=xxxx;options="dictionary string"
a=datachannel:2 RTCWeb label=xxxx;options="dictionary string"
Figure 2 Figure 2
This will cause the offerer (at 192.0.2.2) to initiate an SCTP This will cause the offerer (at 192.0.2.2) to initiate an SCTP
association to port 54321 at 192.0.2.1. association to port 54321 at 192.0.2.1.
7.2. Existing Connection Reuse 10.2. Existing Connection Reuse
Subsequent to the exchange in Section 7.1, another offer/answer Subsequent to the exchange in Section 10.1, another offer/answer
exchange is initiated in the opposite direction. The endpoint at exchange is initiated in the opposite direction. The endpoint at
192.0.2.1, which now acts as the offerer, wishes to continue using 192.0.2.1, which now acts as the offerer, wishes to continue using
the existing association: the existing association:
m=application 54321 SCTP * m=application 54321 SCTP *
c=IN IP4 192.0.2.1 c=IN IP4 192.0.2.1
a=setup:passive a=setup:passive
a=connection:new a=connection:existing
Figure 3 Figure 3
The endpoint at 192.0.2.2 also wishes to use the existing SCTP The endpoint at 192.0.2.2 also wishes to use the existing SCTP
association and responds with the following description: association and responds with the following description:
m=application 9 SCTP * m=application 9 SCTP *
c=IN IP4 192.0.2.2 c=IN IP4 192.0.2.2
a=setup:active a=setup:active
a=connection:new a=connection:existing
Figure 4 Figure 4
The existing SCTP association between 192.0.2.2 and 192.0.2.1 will be The existing SCTP association between 192.0.2.2 and 192.0.2.1 will be
reused. reused.
7.3. SDP description for DTLS Connection 10.3. SDP description for DTLS Connection
An offerer at 192.0.2.2 signals the availability of a T.38 fax An offerer at 192.0.2.2 signals the availability of a T.38 fax
session over SCTP/DTLS. session over SCTP/DTLS.
m=image 54111 SCTP/DTLS t38 m=image 54111 SCTP/DTLS 0
c=IN IP4 192.0.2.2 c=IN IP4 192.0.2.2
a=setup:actpass a=setup:actpass
a=connection:new a=connection:new
a=fingerprint:SHA-1 \ a=fingerprint:SHA-1 \
4A:AD:B9:B1:3F:82:18:3B:54:02:12:DF:3E:5D:49:6B:19:E5:7C:AB 4A:AD:B9:B1:3F:82:18:3B:54:02:12:DF:3E:5D:49:6B:19:E5:7C:AB
a=fmtp:datachannel streams=1
a=datachannel:0 t38 label=xxxx;options="dictionary string"
Figure 5 Figure 5
8. Security Considerations 11. Security Considerations
See RFC 4566 [RFC4566] for security considerations on the use of SDP See RFC 4566 [RFC4566] for security considerations on the use of SDP
in general. See RFC 3264 [RFC3264], RFC 4145 [RFC4145] and RFC 4572 in general. See RFC 3264 [RFC3264], RFC 4145 [RFC4145] and RFC 4572
[RFC4572] for security considerations on establishing media streams [RFC4572] for security considerations on establishing media streams
using offer/answer exchanges. See RFC 4960 [RFC4960] for security using offer/answer exchanges. See RFC 4960 [RFC4960] for security
considerations on SCTP in general and [RFC6083] for security considerations on SCTP in general and [RFC6083] for security
consideration using DTLS on top of SCTP. This specification does not consideration using DTLS on top of SCTP. This specification does not
introduce any new security consideration in addition to the ones introduce any new security consideration in addition to the ones
discussed in those specifications. discussed in those specifications.
9. IANA Considerations 12. IANA Considerations
This document defines three new proto values: 'SCTP', 'SCTP/DTLS' and This document defines three new proto values: 'SCTP', 'SCTP/DTLS' and
'DTLS/SCTP'. Their formats are defined in Section 3. These proto 'DTLS/SCTP'. Their formats are defined in Section 3. These proto
values should be registered by the IANA under "Session Description values should be registered by the IANA under "Session Description
Protocol (SDP) Parameters" under "proto". Protocol (SDP) Parameters" under "proto".
The SDP specification, [RFC4566], states that specifications defining This document defines two SDP session and media-level attributes:
new proto values, like the SCTP, SCTP/DTLS and DTLS/SCTP proto values
defined in this RFC, must define the rules by which their media
format (fmt) namespace is managed. For the SCTP protocol, new
formats SHOULD have an associated MIME registration. Use of an
existing MIME subtype for the format is encouraged. If no MIME
subtype exists, it is RECOMMENDED that a suitable one is registered
through the IETF process [RFC4288] [RFC4289] by production of, or
reference to, a standards-track RFC that defines the transport
protocol for the format.
10. References 'streams'. Its format is defined in Section 5. This attribute
should be registered by IANA under "Session Description Protocol
(SDP) Parameters" under "att-field" (both session and media
level)".
10.1. Normative References 'datachannel'. Its format is defined in Section 6. This
attribute should be registered by IANA under "Session Description
Protocol (SDP) Parameters" under "att-field" (both session and
media level)".
13. References
13.1. 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, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3264] Rosenberg, J. and H. Schulzrinne, "An Offer/Answer Model [RFC3264] Rosenberg, J. and H. Schulzrinne, "An Offer/Answer Model
with Session Description Protocol (SDP)", RFC 3264, with Session Description Protocol (SDP)", RFC 3264,
June 2002. June 2002.
[RFC4145] Yon, D. and G. Camarillo, "TCP-Based Media Transport in [RFC4145] Yon, D. and G. Camarillo, "TCP-Based Media Transport in
the Session Description Protocol (SDP)", RFC 4145, the Session Description Protocol (SDP)", RFC 4145,
skipping to change at page 9, line 44 skipping to change at page 12, line 13
Kozuka, "Stream Control Transmission Protocol (SCTP) Kozuka, "Stream Control Transmission Protocol (SCTP)
Dynamic Address Reconfiguration", RFC 5061, Dynamic Address Reconfiguration", RFC 5061,
September 2007. September 2007.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security [RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246, August 2008. (TLS) Protocol Version 1.2", RFC 5246, August 2008.
[I-D.tuexen-tsvwg-sctp-dtls-encaps] [I-D.tuexen-tsvwg-sctp-dtls-encaps]
Jesup, R., Loreto, S., Stewart, R., and M. Tuexen, "DTLS Jesup, R., Loreto, S., Stewart, R., and M. Tuexen, "DTLS
Encapsulation of SCTP Packets for RTCWEB", Encapsulation of SCTP Packets for RTCWEB",
draft-tuexen-tsvwg-sctp-dtls-encaps-00 (work in progress), draft-tuexen-tsvwg-sctp-dtls-encaps-01 (work in progress),
March 2012. July 2012.
10.2. Informative References 13.2. Informative References
[RFC3436] Jungmaier, A., Rescorla, E., and M. Tuexen, "Transport [RFC3436] Jungmaier, A., Rescorla, E., and M. Tuexen, "Transport
Layer Security over Stream Control Transmission Protocol", Layer Security over Stream Control Transmission Protocol",
RFC 3436, December 2002. RFC 3436, December 2002.
[RFC6083] Tuexen, M., Seggelmann, R., and E. Rescorla, "Datagram [RFC6083] Tuexen, M., Seggelmann, R., and E. Rescorla, "Datagram
Transport Layer Security (DTLS) for Stream Control Transport Layer Security (DTLS) for Stream Control
Transmission Protocol (SCTP)", RFC 6083, January 2011. Transmission Protocol (SCTP)", RFC 6083, January 2011.
[RFC5768] Rosenberg, J., "Indicating Support for Interactive [RFC5768] Rosenberg, J., "Indicating Support for Interactive
 End of changes. 27 change blocks. 
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