draft-ietf-xrblock-rtcp-xr-discard-rle-metrics-09.txt   rfc7097.txt 
XR Block Working Group J. Ott Internet Engineering Task Force (IETF) J. Ott
Internet-Draft V. Singh, Ed. Request for Comments: 7097 V. Singh, Ed.
Intended status: Standards Track Aalto University Category: Standards Track Aalto University
Expires: May 16, 2014 I. Curcio ISSN: 2070-1721 I. Curcio
Nokia Research Center Nokia Research Center
November 12, 2013 January 2014
RTP Control Protocol (RTCP) Extended Report (XR) for Run Length Encoding RTP Control Protocol (RTCP) Extended Report (XR)
(RLE) of Discarded Packets for RLE of Discarded Packets
draft-ietf-xrblock-rtcp-xr-discard-rle-metrics-09
Abstract Abstract
The RTP Control Protocol (RTCP) is used in conjunction with the Real- The RTP Control Protocol (RTCP) is used in conjunction with the Real-
time Transport Protocol (RTP) in to provide a variety of short-term time Transport Protocol (RTP) in order to provide a variety of short-
and long-term reception statistics. The available reporting may term and long-term reception statistics. The available reporting may
include aggregate information across longer periods of time as well include aggregate information across longer periods of time as well
as individual packet reporting. This document specifies a per-packet as individual packet reporting. This document specifies a per-packet
report metric capturing individual packets discarded from the de- report metric capturing individual packets discarded from the de-
jitter buffer after successful reception. jitter buffer after successful reception.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This is an Internet Standards Track document.
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months This document is a product of the Internet Engineering Task Force
and may be updated, replaced, or obsoleted by other documents at any (IETF). It represents the consensus of the IETF community. It has
time. It is inappropriate to use Internet-Drafts as reference received public review and has been approved for publication by the
material or to cite them other than as "work in progress." Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 5741.
This Internet-Draft will expire on May 16, 2014. Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc7097.
Copyright Notice Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the Copyright (c) 2014 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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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 . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Terminology .....................................................4
3. XR Discard RLE Report Block . . . . . . . . . . . . . . . . . 4 3. RTCP XR Discard RLE Report Block ................................4
4. Protocol Operation . . . . . . . . . . . . . . . . . . . . . 5 4. Protocol Operation ..............................................6
4.1. Reporting Node (Receiver) . . . . . . . . . . . . . . . . 6 4.1. Reporting Node (Receiver) ..................................6
4.2. Media Sender . . . . . . . . . . . . . . . . . . . . . . 6 4.2. Media Sender ...............................................6
5. SDP signaling . . . . . . . . . . . . . . . . . . . . . . . . 6 5. SDP Signaling ...................................................6
6. Security Considerations . . . . . . . . . . . . . . . . . . . 7 6. Security Considerations .........................................7
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 7. IANA Considerations .............................................7
7.1. XR Report Block Registration . . . . . . . . . . . . . . 7 7.1. XR Report Block Registration ...............................7
7.2. SDP Parameter Registration . . . . . . . . . . . . . . . 8 7.2. SDP Parameter Registration .................................8
7.3. Contact information for IANA registrations . . . . . . . 8 7.3. Contact Information for IANA Registrations .................8
8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 8 8. Acknowledgments .................................................8
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 9. References ......................................................8
9.1. Normative References . . . . . . . . . . . . . . . . . . 8 9.1. Normative References .......................................8
9.2. Informative References . . . . . . . . . . . . . . . . . 8 9.2. Informative References .....................................9
Appendix A. Metrics represented using RFC6390 Template . . . . . 9 Appendix A. Metrics Represented Using the Template from RFC 6390 ..10
Appendix B. Change Log . . . . . . . . . . . . . . . . . . . . . 10
B.1. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-
metrics-00 . . . . . . . . . . . . . . . . . . . . . . . 10
B.2. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-
metrics-01 . . . . . . . . . . . . . . . . . . . . . . . 10
B.3. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-
metrics-02 . . . . . . . . . . . . . . . . . . . . . . . 10
B.4. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-
metrics-03 . . . . . . . . . . . . . . . . . . . . . . . 10
B.5. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-
metrics-04 . . . . . . . . . . . . . . . . . . . . . . . 11
B.6. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-
metrics-05 . . . . . . . . . . . . . . . . . . . . . . . 11
B.7. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-
metrics-06 . . . . . . . . . . . . . . . . . . . . . . . 11
B.8. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-
metrics-07 . . . . . . . . . . . . . . . . . . . . . . . 11
B.9. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-
metrics-08 . . . . . . . . . . . . . . . . . . . . . . . 11
B.10. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-
metrics-09 . . . . . . . . . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11
1. Introduction 1. Introduction
RTP [RFC3550] provides a transport for real-time media flows such as RTP [RFC3550] provides a transport for real-time media flows such as
audio and video together with the RTP control protocol (RTCP) which audio and video together with the RTP Control Protocol (RTCP), which
provides periodic feedback about the media streams received in a provides periodic feedback about the media streams received in a
specific duration. In addition, RTCP can be used for timely feedback specific duration. In addition, RTCP can be used for timely feedback
about individual events to report (e.g., packet loss) [RFC4585]. about individual events to report (e.g., packet loss) [RFC4585].
Both long-term and short-term feedback enable a media sender to adapt Both long-term and short-term feedback enable a media sender to adapt
its media transmission and/or encoding dynamically to the observed its media transmission and/or encoding dynamically to the observed
path characteristics. path characteristics.
RFC3611 [RFC3611] defines RTCP Extended Reports as a detailed RFC 3611 [RFC3611] defines RTCP Extended Reports as a detailed
reporting framework to provide more than just the coarse Receiver reporting framework to provide more than just the coarse Receiver
Report (RR) statistics. The detailed reporting may enable a media Report (RR) statistics. The detailed reporting may enable a media
sender to react more appropriately to the observed networking sender to react more appropriately to the observed networking
conditions as these can be characterized better, although at the conditions as these can be characterized better, although at the
expense of extra overhead. expense of extra overhead.
Among many other report blocks, RFC3611 specifies the Loss Run Length Among many other report blocks, RFC 3611 specifies the Loss Run
Encoding (RLE) block which reports runs of packets received and lost Length Encoding (RLE) block, which reports runs of packets received
with the granularity of individual packets. This can help both error and lost with the granularity of individual packets. This can help
recovery and path loss characterization. In addition to lost both error recovery and path loss characterization. In addition to
packets, RFC3611 defines the notion of "discarded" packets: packets lost packets, RFC 3611 defines the notion of "discarded" packets:
that were received but dropped from the de-jitter buffer because they packets that were received but dropped from the de-jitter buffer
were either too early (for buffering) or too late (for playout). The because they were either too early (for buffering) or too late (for
"discard rate" metric is part of the VoIP metrics report block even playout). The "discard rate" metric is part of the Voice over IP
though it is not just applicable to audio: it is specified as the (VoIP) metrics report block even though it is not just applicable to
fraction of discarded packets since the beginning of the session. audio: it is specified as the fraction of discarded packets since the
See section 4.7.1 of RFC3611 [RFC3611]. The discard metric is beginning of the session (see Section 4.7.1 of RFC 3611 [RFC3611]).
believed to be applicable to a large class of RTP applications which The discard metric is believed to be applicable to a large class of
use a de-jitter buffer RFC5481 [RFC5481]. RTP applications that use a de-jitter buffer [RFC5481].
Recently proposed extensions to the Extended Reports (XR) reporting Recently proposed extensions to the Extended Reports (XRs) reporting
suggest enhancing this discard metric: suggest enhancing this discard metric:
o Reporting the number of discarded packets in a measurement o Reporting the number of discarded packets in a measurement
interval, i.e., during either the last reporting interval or since interval, i.e., either during the last reporting interval or since
the beginning of the session, as indicated by a flag in the the beginning of the session, as indicated by a flag in the
suggested XR report [RFC7002]. If an endpoint needs to report suggested XR [RFC7002]. If an endpoint needs to report packet
packet discard due to other reasons than early- and late-arrival discard due to reasons other than early and late arrival (for
(for example, discard due to duplication, redundancy, etc.) then example, discard due to duplication, redundancy, etc.), then it
it should consider using the Discarded Packets Report Block should consider using the Discarded Packets report block
[RFC7002]. [RFC7002].
o Reporting gaps and bursts of discarded packets during a o Reporting gaps and bursts of discarded packets during a
measurement interval, i.e., the last reporting interval or the measurement interval, i.e., the last reporting interval or the
duration of the session [RFC7003]. duration of the session [RFC7003].
o Reporting the sum of payload bytes discarded during a measurement o Reporting the sum of payload bytes discarded during a measurement
interval, i.e., the last reporting interval or the duration of the interval, i.e., the last reporting interval or the duration of the
session [I-D.ietf-xrblock-rtcp-xr-bytes-discarded-metric]. session [DISCARD-METRIC].
However, none of these metrics allow a receiver to report precisely However, none of these metrics allow a receiver to report precisely
which packets were discarded. While this information could in theory which packets were discarded. While this information could in theory
be derived from high-frequency reporting on the number of discarded be derived from high-frequency reporting on the number of discarded
packets [RFC7002] or from the gap/burst report [RFC7003], these two packets [RFC7002] or from the gap/burst report [RFC7003], these two
mechanisms do not appear feasible: The former would require an unduly mechanisms do not appear feasible: the former would require an unduly
high amount of reporting which still might not be sufficient due to high amount of reporting, which still might not be sufficient due to
the non-deterministic scheduling of RTCP packets. The latter incur the non-deterministic scheduling of RTCP packets. The latter incurs
significant complexity and reporting overhead and might still not significant complexity and reporting overhead and might still not
deliver the desired accuracy. deliver the desired accuracy.
This document defines a discard report block following the idea of This document defines a discard report block following the idea of
the run-length encoding applied for lost and received packets in the run-length encoding applied for lost and received packets in
[RFC3611]. [RFC3611].
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", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in BCP 14, RFC 2119 document are to be interpreted as described in BCP 14, RFC 2119
[RFC2119]. [RFC2119].
The terminology defined in RTP [RFC3550] and in the extensions for XR The terminology defined in RTP [RFC3550] and in the extensions for XR
reporting [RFC3611] applies. reporting [RFC3611] applies.
3. XR Discard RLE Report Block 3. RTCP XR Discard RLE Report Block
The XR Discard RLE report block uses the same format as specified for
the loss and duplicate report blocks in [RFC3611]. Figure 1
describes the packet format. The fields "BT", "T", "block length",
"SSRC of source", "begin_seq", and "end_seq" have the same semantics
and representation as defined in [RFC3611], with the addition of the
"E" flag to indicate the reason for discard. The "chunks" encoding
the run length have the same representation as in RFC3611, but encode
discarded packets. A definition of a discarded packet is given in
[RFC7002].
0 1 2 3 The RTCP XR Discard RLE report block uses the same format as
0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 specified for the loss and duplicate report blocks in RFC 3611
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ [RFC3611]. Figure 1 describes the packet format. The fields "BT",
| BT=DRLE |rsvd |E| T | block length | "T", "block length", "SSRC of source", "begin_seq", and "end_seq"
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ have the same semantics and representation as defined in [RFC3611],
| SSRC of source | with the addition of the "E" flag to indicate the reason for discard.
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The "chunks" encoding the run length have the same representation as
| begin_seq | end_seq | in RFC 3611, but encode discarded packets. A definition of a
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ discarded packet is given in RFC 7002 [RFC7002].
| chunk 1 | chunk 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: ... :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| chunk n-1 | chunk n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: XR Discard RLE Report Block 0 1 2 3
0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| BT=25 |rsvd |E| T | block length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SSRC of source |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| begin_seq | end_seq |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| chunk 1 | chunk 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: ... :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| chunk n-1 | chunk n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Block Type (BT, 8 bits): A Run-length encoded Discarded Packets Figure 1: RTCP XR Discard RLE Report Block
Report Block is identified by the constant DRLE.
[Note to RFC Editor: please replace DRLE with the IANA provided RTCP Block Type (BT, 8 bits): A Discard RLE report block is identified by
XR block type for this block. Please remove this note prior to the constant 25.
publication as an RFC.]
rsvd (3 bits): This field is reserved for future definition. In the rsvd (3 bits): This field is reserved for future definition. In the
absence of such definition, the bits in this field MUST be set to absence of such definition, the bits in this field MUST be set to
zero and MUST be ignored by the receiver. zero and MUST be ignored by the receiver.
The 'E' bit is introduced to distinguish between packets discarded The 'E' bit is introduced to distinguish between packets discarded
due to early arrival and those discarded due to late arrival. The due to early arrival and those discarded due to late arrival. The
'E' bit is set to '1' if the chunks represent packets discarded due 'E' bit is set to '1' if the chunks represent packets discarded due
to too early arrival and is set to '0' otherwise. to arriving too early and is set to '0' otherwise.
In case both early and late discarded packets shall be reported, two In case both early and late discarded packets shall be reported, two
Discard RLE report blocks MUST be included; their sequence number Discard RLE report blocks MUST be included; their sequence number
range MAY overlap, but individual packets MUST only be reported as range MAY overlap, but individual packets MUST only be reported as
either early or late and not appear marked in both. If packets either early or late and not appear marked in both. If packets
appear in both report blocks, the conflicting packets are ignored. appear in both report blocks, the conflicting packets will be
Packets reported in neither are considered to be properly received ignored. Packets not reported in either block are considered to be
and not discarded. properly received and not discarded.
Discard RLE Report Blocks SHOULD be sent in conjunction with an RTCP Discard RLE report blocks SHOULD be sent in conjunction with an RTCP
RR as a compound RTCP packet. RR as a compound RTCP packet.
4. Protocol Operation 4. Protocol Operation
This section describes the behavior of the reporting node (= media This section describes the behavior of the reporting node (= media
receiver) and the media sender. receiver) and the media sender.
4.1. Reporting Node (Receiver) 4.1. Reporting Node (Receiver)
Transmission of RTCP XR Discard RLE Reports is up to the discretion Transmission of RTCP XR Discard RLE report blocks is up to the
of the media receiver, as is the reporting granularity. However, it discretion of the media receiver, as is the reporting granularity.
is RECOMMENDED that the media receiver signals all discarded packets However, it is RECOMMENDED that the media receiver signal all
using the method defined in this document. If all packets over a discarded packets using the method defined in this document. If all
reporting period were discarded, the media receiver MAY use the packets over a reporting period are discarded, the media receiver MAY
Discard Report Block [RFC7002] instead. In case of limited available use the Discard Report Block [RFC7002] instead. In case of limited
reporting bandwidth, it is up to the receiver whether or not to available reporting bandwidth, it is up to the receiver whether or
include RTCP XR Discard RLE reports. not to include RTCP XR Discard RLE report blocks.
The media receiver MAY send the Discard RLE Reports as part of the The media receiver MAY send the Discard RLE report blocks as part of
regularly scheduled RTCP packets as per RFC3550. It MAY also include the regularly scheduled RTCP packets, as per RFC 3550. It MAY also
Discard RLE Reports in immediate or early feedback packets as per include Discard RLE report blocks in immediate or early feedback
RFC4585. packets, as per RFC 4585.
4.2. Media Sender 4.2. Media Sender
The media sender MUST be prepared to operate without receiving any The media sender MUST be prepared to operate without receiving any
Discard RLE reports. If Discard RLE reports are generated by the Discard RLE report blocks. If Discard RLE report blocks are
media receiver, the media sender cannot rely on all these reports generated by the media receiver, the media sender cannot rely on all
being received, nor can the media sender rely on a regular generation these reports being received, nor can the media sender rely on a
pattern from the media receiver. regular generation pattern from the media receiver.
However, if the media sender receives any RTCP reports but no Discard However, if the media sender receives RTCP XR reports but the reports
RLE report blocks and is aware that the media receiver supports contain no Discard RLE report blocks and is aware that the media
Discard RLE report blocks, it MAY assume that no packets were receiver supports Discard RLE report blocks, it MAY assume that no
discarded at the media receiver. packets were discarded at the media receiver.
5. SDP signaling 5. SDP Signaling
A participant of a media session MAY use SDP to signal its support A participant of a media session MAY use SDP to signal its support
for the report block specified in this document or use them without for the report block specified in this document or use them without
any prior signaling (see section 5 of [RFC3611]). any prior signaling (see Section 5 of RFC 3611 [RFC3611]).
For signaling in SDP, the RTCP XR attribute as defined in [RFC3611] For signaling in SDP, the RTCP XR attribute as defined in RFC 3611
MUST be used. The SDP [RFC4566] attribute 'xr-format' defined in [RFC3611] MUST be used. The SDP [RFC4566] attribute 'xr-format'
RFC3611 is augmented as described in the following to indicate the defined in RFC 3611 is augmented as described in the following to
the discard RLE metric. indicate the discard RLE metric.
rtcp-xr-attrib = "a=" "rtcp-xr" ":" [xr-format *(SP xr-format)] rtcp-xr-attrib = "a=" "rtcp-xr" ":" [xr-format *(SP xr-format)]
CRLF ; defined in [RFC3611] CRLF ; defined in [RFC3611]
xr-format =/ xr-discard-rle xr-format =/ xr-discard-rle
xr-discard-rle = "discard-rle" xr-discard-rle = "discard-rle"
The parameter 'discard-rle' is used to indicate support for the The parameter 'discard-rle' is used to indicate support for the
Discard RLE Report Block defined in Section 3. Discard RLE report block defined in Section 3.
When SDP is used in Offer/Answer context, the mechanism defined in When SDP is used in Offer/Answer context, the mechanism defined in
[RFC3611] for unilateral "rtcp-xr" attribute parameters applies (see RFC 3611 [RFC3611] for unilateral "rtcp-xr" attribute parameters
section 5.2 of [RFC3611]). applies (see Section 5.2 of RFC 3611 [RFC3611]).
6. Security Considerations 6. Security Considerations
The Discard RLE block provides per-packet statistics so the risk to The Discard RLE report block provides per-packet statistics so the
confidentiality documented in Section 7, paragraph 3 of [RFC3611] risk to confidentiality documented in Section 7, Paragraph 3, of RFC
applies. In some situations, returning very detailed error 3611 [RFC3611] applies. In some situations, returning very detailed
information (e.g., over-range measurement or measurement unavailable) error information (e.g., over-range measurement or measurement
using this report block can provide an attacker with insight into the unavailable) using this report block can provide an attacker with
security processing. Implementers should consider the guidance in insight into the security processing. Implementers should consider
[I-D.ietf-avt-srtp-not-mandatory] for using appropriate security the guidance in [NO-SRTP] for using appropriate security mechanisms,
mechanisms, i.e., where security is a concern, the implementation i.e., where security is a concern, the implementation should apply
should apply encryption and authentication to the report block. For encryption and authentication to the report block. For example, this
example this can be achieved by using the AVPF profile together with can be achieved by using the AVPF profile together with the Secure
the Secure RTP profile as defined in [RFC3711]; an appropriate RTP profile as defined in RFC 3711 [RFC3711]; an appropriate
combination of the two profiles (an "SAVPF") is specified in combination of the two profiles (an "SAVPF") is specified in RFC 5124
[RFC5124]. However, other mechanisms also exist (documented in [RFC5124]. However, other mechanisms also exist [SRTP-OPTIONS] and
[I-D.ietf-avtcore-rtp-security-options]) and might be more suitable. might be more suitable.
Additionally, The security considerations of [RFC3550], [RFC3611], Additionally, The security considerations of RFC 3550 [RFC3550], RFC
and [RFC4585] apply. 3611 [RFC3611], and RFC 4585 [RFC4585] apply.
7. IANA Considerations 7. IANA Considerations
New block types for RTCP XR are subject to IANA registration. For New block types for RTCP XR are subject to IANA registration. For
general guidelines on IANA considerations for RTCP XR, refer to general guidelines on IANA considerations for RTCP XR, refer to RFC
[RFC3611]. 3611.
7.1. XR Report Block Registration 7.1. XR Report Block Registration
This document extends the IANA "RTP Control Protocol Extended Reports This document extends the IANA "RTP Control Protocol Extended Reports
(RTCP XR) Block Type Registry" by a new value: DRLE (Discard RLE (RTCP XR) Block Type Registry" by assigning value 25 to DRLE (Discard
Report). RLE Report).
[Note to RFC Editor: please replace DRLE with the IANA provided RTCP
XR block type for this block here and in the diagrams above. Please
remove this note prior to publication as an RFC.]
7.2. SDP Parameter Registration 7.2. SDP Parameter Registration
This document registers a new parameters for the Session Description This document registers 'discard-rle' in the "RTCP XR SDP
Protocol (SDP), "discard-rle" in the "RTP Control Protocol Extended Parameters".
Reports (RTCP XR) Session Description Protocol (SDP) Parameters
Registry".
7.3. Contact information for IANA registrations 7.3. Contact Information for IANA Registrations
Joerg Ott (jo@comnet.tkk.fi) Joerg Ott (jo@comnet.tkk.fi)
Aalto University Comnet, Otakaari 5A, 02150 Espoo, Finland. Aalto University Comnet, Otakaari 5A, 02150 Espoo, Finland.
8. Acknowledgments 8. Acknowledgments
The authors would like to thank Alan Clark, Roni Even, Sam Hartman, The authors would like to thank Alan Clark, Roni Even, Sam Hartman,
Colin Perkins, Dan Romascanu, Dan Wing, and Qin Wu for providing Colin Perkins, Dan Romascanu, Dan Wing, and Qin Wu for providing
valuable feedback on earlier versions of this draft. valuable feedback on earlier draft versions of this document.
9. References 9. References
9.1. Normative References 9.1. 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.
[RFC3550] Schulzrinne, H., Casner, S., Frederick, R., and V. [RFC3550] Schulzrinne, H., Casner, S., Frederick, R., and V.
Jacobson, "RTP: A Transport Protocol for Real-Time Jacobson, "RTP: A Transport Protocol for Real-Time
skipping to change at page 9, line 20 skipping to change at page 9, line 22
Applicability Statement", RFC 5481, March 2009. Applicability Statement", RFC 5481, March 2009.
[RFC3711] Baugher, M., McGrew, D., Naslund, M., Carrara, E., and K. [RFC3711] Baugher, M., McGrew, D., Naslund, M., Carrara, E., and K.
Norrman, "The Secure Real-time Transport Protocol (SRTP)", Norrman, "The Secure Real-time Transport Protocol (SRTP)",
RFC 3711, March 2004. RFC 3711, March 2004.
[RFC5124] Ott, J. and E. Carrara, "Extended Secure RTP Profile for [RFC5124] Ott, J. and E. Carrara, "Extended Secure RTP Profile for
Real-time Transport Control Protocol (RTCP)-Based Feedback Real-time Transport Control Protocol (RTCP)-Based Feedback
(RTP/SAVPF)", RFC 5124, February 2008. (RTP/SAVPF)", RFC 5124, February 2008.
[I-D.ietf-avt-srtp-not-mandatory] [NO-SRTP] Perkins, C. and M. Westerlund, "Securing the RTP Protocol
Perkins, C. and M. Westerlund, "Securing the RTP Protocol
Framework: Why RTP Does Not Mandate a Single Media Framework: Why RTP Does Not Mandate a Single Media
Security Solution", draft-ietf-avt-srtp-not-mandatory-13 Security Solution", Work in Progress, October 2013.
(work in progress), May 2013.
[I-D.ietf-avtcore-rtp-security-options] [SRTP-OPTIONS]
Westerlund, M. and C. Perkins, "Options for Securing RTP Westerlund, M. and C. Perkins, "Options for Securing RTP
Sessions", draft-ietf-avtcore-rtp-security-options-04 Sessions", Work in Progress, November 2013.
(work in progress), July 2013.
[I-D.ietf-xrblock-rtcp-xr-bytes-discarded-metric]
Singh, V., Ott, J., and I. Curcio, "RTP Control Protocol
(RTCP) Extended Report (XR) for Bytes Discarded Metric",
draft-ietf-xrblock-rtcp-xr-bytes-discarded-metric-00 (work
in progress), October 2013.
Appendix A. Metrics represented using RFC6390 Template [DISCARD-METRIC]
Singh, V., Ed., Ott, J., and I. Curcio, "RTP Control
Protocol (RTCP) Extended Report (XR) for Bytes Discarded
Metric", Work in Progress, November 2013.
RFC EDITOR NOTE: please change XXXX in [RFCXXXX] by the new RFC Appendix A. Metrics Represented Using the Template from RFC 6390
number, when assigned.
a. Run-length encoding of Discarded RTP Packets Metric a. RLE of Discarded RTP Packets Metric
* Metric Name: Run-length encoding of Discarded RTP Packets * Metric Name: RLE - Run-length encoding of Discarded RTP
Metric. Packets Metric.
* Metric Description: Instances of RTP packets discarded over * Metric Description: Instances of RTP packets discarded over
the period covered by this report. the period covered by this report.
* Method of Measurement or Calculation: See section 3, for the * Method of Measurement or Calculation: See Section 3 for the
definition of Discard run-length encoding [RFCXXXX] and definition of Discard RLE, and Section 4.1 of RFC 3611 for
section 4.1 of RFC3611 for Run-length encoding. RLE.
* Units of Measurement: Every RTP packet in the interval is * Units of Measurement: Every RTP packet in the interval is
reported as discarded or not. See section 3 for the reported as discarded or not. See Section 3 for the
definition of [RFCXXXX]. definition.
* Measurement Point(s) with Potential Measurement Domain: The * Measurement Point(s) with Potential Measurement Domain: The
measurement of these metrics is made at the receiving end of measurement of these metrics is made at the receiving end of
the RTP stream. the RTP stream.
* Measurement Timing: Each RTP packet between a beginning * Measurement Timing: Each RTP packet between a beginning
sequence number (begin_seq) and ending sequence number sequence number (begin_seq) and ending sequence number
(end_seq) are reported as discarded or not. See section 3 for (end_seq) is reported as discarded or not. See Section 3 for
the definition of Discard run-length encoding [RFCXXXX]. the definition of Discard RLE.
* Use and applications: See section 1, paragraph 1 of [RFCXXXX].
* Reporting model: See RFC3611.
Appendix B. Change Log
Note to the RFC-Editor: please remove this section prior to
publication as an RFC.
B.1. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-metrics-00
o Changed the interval flag from 1 to 2 bits in the discarded bytes
report. Also added the measurement identification tag to the
block.
o Added this section.
B.2. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-metrics-01
o Removed the measurement identification tag in the bytes discarded
block.
B.3. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-metrics-02
o Removed the extra Tag bits from the Discarded bytes XR block.
o Clarified use of measurement identity block in Section 4 and 5.2
B.4. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-metrics-03
o Added explanation for block length in bytes discarded block.
o Added an acknowledgement section.
B.5. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-metrics-04
o Added Block Type definition to each XRBlock.
o Made changes requested in WGLC.
B.6. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-metrics-05
o Made changes requested by SDP directorate.
B.7. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-metrics-06
o Editorial fixes based on review from Gen-art and IESG review.
B.8. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-metrics-07
o Editorial fixes based on review from IESG.
o Editorial fixes based on Security and PM directorate.
o Split bytes discarded from this draft to another.
o Updated Security Considerations Section.
o This draft now normatively cites the definition of discards in
'packets discarded' draft.
B.9. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-metrics-08
o Editorial fixes: Updated references from drafts to RFCs.
o Updated RFC6390 template with RTP keyword.
B.10. changes in draft-ietf-xrblock-rtcp-xr-discard-rle-metrics-09 * Use and applications: See Section 1, paragraph 1.
o Removed (RLE) from RFC6390 template. * Reporting model: See RFC 3611.
Authors' Addresses Authors' Addresses
Joerg Ott Joerg Ott
Aalto University Aalto University
School of Electrical Engineering School of Electrical Engineering
Otakaari 5 A Otakaari 5 A
Espoo, FIN 02150 Espoo, FIN 02150
Finland Finland
Email: jo@comnet.tkk.fi EMail: jo@comnet.tkk.fi
Varun Singh (editor) Varun Singh (editor)
Aalto University Aalto University
School of Electrical Engineering School of Electrical Engineering
Otakaari 5 A Otakaari 5 A
Espoo, FIN 02150 Espoo, FIN 02150
Finland Finland
Email: varun@comnet.tkk.fi EMail: varun@comnet.tkk.fi
URI: http://www.netlab.tkk.fi/~varun/ URI: http://www.netlab.tkk.fi/~varun/
Igor D.D. Curcio Igor D.D. Curcio
Nokia Research Center Nokia Research Center
P.O. Box 1000 (Visiokatu 3) P.O. Box 1000 (Visiokatu 3)
Tampere, FIN 33721 Tampere, FIN 33721
Finland Finland
Email: igor.curcio@nokia.com EMail: igor.curcio@nokia.com
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