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5 632 M
(Internet Engineering Task Force Sally Floyd) s
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(INTERNET-DRAFT ICIR) s
5 610 M
(Intended status: Experimental Eddie Kohler) s
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(Expires: 18 May 2008 UCLA) s
5 588 M
( 18 November 2007) s
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( Profile for Datagram Congestion Control Protocol \(DCCP\)) s
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( Congestion ID 4: TCP-Friendly Rate Control for Small Packets \(TFRC-SP\)) s
5 533 M
( draft-ietf-dccp-ccid4-01.txt) s
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(Status of This Memo) s
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( By submitting this Internet-Draft, each author represents that any) s
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( applicable patent or other IPR claims of which he or she is aware) s
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( have been or will be disclosed, and any of which he or she becomes) s
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( aware will be disclosed, in accordance with Section 6 of BCP 79.) s
5 423 M
( Internet-Drafts are working documents of the Internet Engineering) s
5 412 M
( Task Force \(IETF\), its areas, and its working groups. Note that) s
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( other groups may also distribute working documents as Internet-) s
5 390 M
( Drafts.) s
5 368 M
( Internet-Drafts are draft documents valid for a maximum of six months) s
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( and may be updated, replaced, or obsoleted by other documents at any) s
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( time. It is inappropriate to use Internet-Drafts as reference) s
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( material or to cite them other than as "work in progress.") s
5 313 M
( The list of current Internet-Drafts can be accessed at) s
5 302 M
( http://www.ietf.org/ietf/1id-abstracts.txt.) s
5 280 M
( The list of Internet-Draft Shadow Directories can be accessed at) s
5 269 M
( http://www.ietf.org/shadow.html.) s
5 247 M
( This Internet-Draft will expire on 18 May 2008.) s
5 225 M
(Copyright Notice) s
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( Copyright \(C\) The IETF Trust \(2007\).) s
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(Abstract) s
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( This document specifies an experimental profile for Congestion) s
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( Control Identifier 4, the Small-Packet variant of TCP-Friendly Rate) s
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(Floyd, et al. Expires: 18 May 2008 [Page 1]) s
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5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
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( Control \(TFRC\), in the Datagram Congestion Control Protocol \(DCCP\).) s
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( CCID 4 is for experimental use, and uses TFRC-SP [RFC4828], a variant) s
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( of TFRC designed for applications that send small packets. CCID 4 is) s
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( considered experimental because TFRC-SP is itself experimental, and) s
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( is not proposed for widespread deployment in the global Internet at) s
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( this time. The goal for TFRC-SP is to achieve roughly the same) s
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( bandwidth in bits per second \(bps\) as a TCP flow using packets of up) s
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( to 1500 bytes but experiencing the same level of congestion. CCID 4) s
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( is for experimental use for senders that send small packets and would) s
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( like a TCP-friendly sending rate, possibly with Explicit Congestion) s
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( Notification \(ECN\), while minimizing abrupt rate changes.) s
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(Floyd, et al. Expires: 18 May 2008 [Page 2]) s
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5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
5 687 M
( TO BE DELETED BY THE RFC EDITOR UPON PUBLICATION:) s
5 665 M
( Changes from draft-ietf-dccp-ccid4-00.txt:) s
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( * Added that the RFC 4342 errata applies to CCID 4 as well. From) s
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( email from Leandro Sales.) s
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( * Added the phrase "If the sender is calculating the loss event rate) s
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( itself" to a non-normative description in Section 5. Feedback from) s
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( Gerrit Renker.) s
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( * Deleted the Send Dropped Packets feature, since it is not used in) s
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( CCID 4. In CCID 4, the Dropped Packets option is mandatory.) s
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( Changes from draft-floyd-dccp-ccid4-01.txt:) s
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( * Title changed to draft-ietf-dccp-ccid4-00.txt.) s
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( * Incorporated material from draft-kohler-dccp-ccid3-drops-01.txt.) s
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( * Added a reference to RFC3448bis.) s
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( * Added a sentence saying that this is Experimental because TFRC-SP) s
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( is Experimental.) s
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( * General editing in response to feedback from Gorry.) s
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( Changes from draft-floyd-dccp-ccid4-00.txt:) s
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( * Added a subsection describing calculation of the average loss) s
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( interval in TFRC-SP.) s
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( * Changed the assumed DCCP-Data header size from 12 bytes to 16) s
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( bytes, for 48-bit sequence numbers. Feedback from Ian McDonald.) s
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( * Added that the CCID4 sender can send two packets in a burst, if) s
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( limited by OS granularity. From Ian McDonald.) s
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( * Added that the implementor may track Faster Restart and implement) s
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( it before an explicit update to the CCID4 RFC. From Ian McDonald.) s
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( * Added an example to Section 8.4 of when errors can occur in using) s
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( the Window Counter to detect loss intervals of at most two round-trip) s
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( times.) s
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( Changes from draft-floyd-ccid4-00.txt:) s
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( * Added the Dropped Packets option for reporting the number of) s
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(Floyd, et al. Expires: 18 May 2008 [Page 3]) s
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5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
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( packets dropped in a loss interval.) s
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( * Added examples to Section 8.4 of the receiver incorrectly inferring) s
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( whether a loss interval was short or not.) s
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( END OF SECTION TO BE DELETED.) s
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(Table of Contents) s
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( 1. Introduction ....................................................6) s
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( 2. Conventions .....................................................6) s
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( 3. Usage ...........................................................7) s
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( 3.1. Relationship with TFRC .....................................7) s
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( 3.2. Example Half-Connection ....................................7) s
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( 4. Connection Establishment ........................................8) s
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( 5. Congestion Control on Data Packets ..............................8) s
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( 5.1. Response to Idle and Application-limited Periods ..........10) s
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( 5.2. Response to Data Dropped and Slow Receiver ................10) s
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( 5.3. Packet Sizes ..............................................10) s
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( 6. Acknowledgements ...............................................10) s
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( 6.1. Loss Interval Definition ..................................10) s
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( 6.2. Congestion Control on Acknowledgements ....................11) s
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( 6.3. Acknowledgements of Acknowledgements ......................11) s
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( 6.4. Quiescence ................................................11) s
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( 7. Explicit Congestion Notification ...............................11) s
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( 8. Options and Features ...........................................11) s
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( 8.1. Window Counter Value ......................................12) s
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( 8.2. Elapsed Time Options ......................................12) s
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( 8.3. Receive Rate Option .......................................13) s
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( 8.4. Send Loss Event Rate Feature ..............................13) s
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( 8.5. Loss Event Rate Option ....................................13) s
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( 8.6. Loss Intervals Option .....................................13) s
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( 8.7. Dropped Packets Option ....................................14) s
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( 8.7.1. Example ............................................15) s
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( 9. Verifying Congestion Control Compliance With ECN ...............16) s
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( 9.1. Verifying the ECN Nonce Echo ..............................16) s
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( 9.2. Verifying the Reported Loss Intervals and Loss Event Rate) s
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( ................................................................17) s
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( 10. Implementation Issues .........................................17) s
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( 10.1. Timestamp Usage ..........................................17) s
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( 10.2. Determining Loss Events at the Receiver ..................17) s
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( 10.3. Sending Feedback Packets .................................17) s
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( 11. Security Considerations .......................................17) s
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( 12. IANA Considerations ...........................................17) s
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( 12.1. Reset Codes ..............................................17) s
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( 12.2. Option Types .............................................18) s
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( 12.3. Feature Numbers ..........................................18) s
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( 13. Thanks ........................................................18) s
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(Floyd, et al. Expires: 18 May 2008 [Page 4]) s
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5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
5 687 M
( Normative References ..............................................18) s
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( Informative References ............................................19) s
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( Authors' Addresses ................................................20) s
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( Full Copyright Statement ..........................................20) s
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( Intellectual Property .............................................20) s
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( Acknowledgement ...................................................21) s
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(List of Tables) s
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( Table 1: DCCP CCID 4 Options ......................................11) s
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( Table 2: DCCP CCID 4 Feature Numbers ..............................12) s
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(Floyd, et al. Expires: 18 May 2008 [Page 5]) s
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5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
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(1. Introduction) s
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( This document contains the profile for Congestion Control Identifier) s
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( 4, TCP-Friendly Rate Control for Small Packets \(TFRC-SP\), in the) s
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( Datagram Congestion Control Protocol \(DCCP\) [RFC4340]. CCID 4) s
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( differs from CCID 3 in that CCID 4 uses TFRC-SP, the Small-Packet) s
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( variant of TFRC, while CCID 3 [RFC4342] uses standard TFRC [RFC3448].) s
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( This document assumes that the reader is familiar with [RFC4342],) s
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( instead of repeating from that document unnecessarily.) s
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( CCID 4 differs from CCID 3 only in the following respects:) s
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( o Header size: For TFRC-SP, the allowed transmit rate in bytes per) s
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( second is reduced by a factor that accounts for packet header) s
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( size. This is specified for TFRC-SP in Section 4.2 of [RFC4828],) s
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( and described for CCID 4 in Section 5 below.) s
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( o Minimum sending rate: TFRC-SP enforces a minimum interval of) s
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( 10 milliseconds between data packets. This is specified for TFRC-) s
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( SP in Section 4.3 of [RFC4828], and described for CCID 4 in) s
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( Section 5 below.) s
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( o Loss rates for short loss intervals: For short lost intervals of) s
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( at most two round-trip times, the loss rate is computed by) s
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( counting the actual number of packets lost or marked. For such a) s
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( short loss interval with N data packets, including K lost or) s
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( marked data packets, the loss interval length is calculated as) s
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( N/K, instead of as N. This is specified for TFRC-SP in Section) s
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( 4.4 of [RFC4828]. If the sender is computing the loss event rate,) s
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( the Dropped Packets option specified in Section 8.7 is required,) s
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( in addition to the default CCID 3's Loss Intervals option.) s
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( Section 8.7 describes the use of the Dropped Packets option in) s
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( calculating the loss event rate. The computation of the loss rate) s
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( by the receiver for the Loss Event Rate option is described for) s
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( CCID 4 in Section 8.4 below.) s
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( o The nominal segment size: In TFRC-SP, the nominal segment size) s
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( used by the TCP throughput equation is set to 1460 bytes. This is) s
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( specified for TFRC-SP in Section 4.5 of [RFC3448], and described) s
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( for CCID 4 in Section 5 below.) s
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(2. Conventions) s
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( The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",) s
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( "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this) s
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( document are to be interpreted as described in [RFC2119].) s
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(Floyd, et al. Expires: 18 May 2008 Section 2. [Page 6]) s
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5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
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( Additional terminology is described in Section 2 of [RFC4342].) s
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(3. Usage) s
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( Like CCID 3, CCID 4's congestion control is appropriate for flows) s
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( that would prefer to minimize abrupt changes in the sending rate,) s
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( including streaming media applications with small or moderate) s
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( receiver buffering before playback.) s
5 588 M
( CCID 4 is designed to be used either by applications that use a small) s
5 577 M
( fixed segment size, or by applications that change their sending rate) s
5 566 M
( by varying the segment size. If CCID 4 is used by an application) s
5 555 M
( that varies its segment size in response to changes in the allowed) s
5 544 M
( sending rate in bps, we note that CCID 4 doesn't dictate the segment) s
5 533 M
( size to be used by the application; this is done by the application) s
5 522 M
( itself. The CCID 4 sender determines the allowed sending rate in) s
5 511 M
( bps, in response to on-going feedback from the CCID 4 receiver, and) s
5 500 M
( the application can use information about the current allowed sending) s
5 489 M
( rate to decide whether to change the current segment size.) s
5 467 M
( We note that in some environments there will be a feedback loop, with) s
5 456 M
( changes in the packet size or in the sending rate in bps affecting) s
5 445 M
( congestion along the path, therefore affecting the allowed sending) s
5 434 M
( rate in the future.) s
5 412 M
(3.1. Relationship with TFRC) s
5 390 M
( The congestion control mechanisms described here follow the TFRC-SP) s
5 379 M
( mechanism specified in [RFC4828]. As with CCID 3, conformant CCID 4) s
5 368 M
( implementations MAY track updates to the TCP throughput equation) s
5 357 M
( directly, as updates are standardized in the IETF, rather than) s
5 346 M
( waiting for revisions of this document. This document is based on) s
5 335 M
( CCID 3 [RFC4342] as modified by the RFC 4342 Errata [RFC4342Errat],) s
5 324 M
( and on TFRC [RFC3448] as modified by the RFC 3448 Errata) s
5 313 M
( [RFC3448Errat]. \(We don't expect that errata would be added to CCID) s
5 302 M
( 3 that didn't apply to CCID 4, but if this should happen, we would) s
5 291 M
( say this explicitly in the errata.\) If [RFC3448bis] is standardized) s
5 280 M
( in the IETF as a revision of [RFC3448], then [RFC3448bis] MAY be) s
5 269 M
( implemented with CCID4 without having to wait for an explicit update) s
5 258 M
( to this document.) s
5 236 M
(3.2. Example Half-Connection) s
5 214 M
( This example shows the typical progress of a half-connection using) s
5 203 M
( CCID 4's TFRC Congestion Control, not including connection initiation) s
5 192 M
( and termination. The example is informative, not normative. This) s
5 181 M
( example differs from that for CCID 3 in [RFC4342] only in that the) s
5 170 M
( allowed transmit rate is determined by [RFC4828] as well as by) s
5 126 M
(Floyd, et al. Expires: 18 May 2008 Section 3.2. [Page 7]) s
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%%BeginPageSetup
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24 24 translate
/pagenum 8 def
/fname (draft-ietf-dccp-ccid4-01.txt) def
/fdir () def
/ftail (draft-ietf-dccp-ccid4-01.txt) def
/user_header_p false def
%%EndPageSetup
5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
5 687 M
( [RFC3448].) s
5 665 M
( 1. The sender transmits DCCP-Data packets, where the sending rate is) s
5 654 M
( governed by the allowed transmit rate as specified in [RFC4828].) s
5 643 M
( Each DCCP-Data packet has a sequence number, and the DCCP header's) s
5 632 M
( CCVal field contains the window counter value, used by the) s
5 621 M
( receiver in determining when multiple losses belong in a single) s
5 610 M
( loss event.) s
5 588 M
( In the typical case of an ECN-capable half-connection, each DCCP-) s
5 577 M
( Data and DCCP-DataAck packet is sent as ECN-Capable, with either) s
5 566 M
( the ECT\(0\) or the ECT\(1\) codepoint set. The use of the ECN Nonce) s
5 555 M
( with TFRC is described in Section 9.) s
5 533 M
( 2. The receiver sends DCCP-Ack packets acknowledging the data packets) s
5 522 M
( at least once per round-trip time, unless the sender is sending at) s
5 511 M
( a rate of less than one packet per round-trip time [RFC3448]) s
5 500 M
( \(Section 6\). Each DCCP-Ack packet uses a sequence number,) s
5 489 M
( identifies the most recent packet received from the sender, and) s
5 478 M
( includes feedback about the recent loss intervals experienced by) s
5 467 M
( the receiver.) s
5 445 M
( 3. The sender continues sending DCCP-Data packets as controlled by) s
5 434 M
( the allowed transmit rate. Upon receiving DCCP-Ack packets, the) s
5 423 M
( sender updates its allowed transmit rate as specified in [RFC3448]) s
5 412 M
( \(Section 4.3\) and [RFC4828]. This update is based upon a loss) s
5 401 M
( event rate calculated by the sender, based on the receiver's loss) s
5 390 M
( intervals feedback. If it prefers, the sender can also use a loss) s
5 379 M
( event rate calculated and reported by the receiver.) s
5 357 M
( 4. The sender estimates round-trip times and calculates a nofeedback) s
5 346 M
( time, as specified in [RFC3448] \(Section 4.4\). If no feedback is) s
5 335 M
( received from the receiver in that time \(at least four round-trip) s
5 324 M
( times\), the sender halves its sending rate.) s
5 302 M
(4. Connection Establishment) s
5 280 M
( The connection establishment is as specified in Section 4 of) s
5 269 M
( [RFC4342].) s
5 247 M
(5. Congestion Control on Data Packets) s
5 225 M
( CCID 4 uses the congestion control mechanisms of TFRC [RFC3448] and) s
5 214 M
( TFRC-SP [RFC4828]. [RFC4828] MUST be considered normative except) s
5 203 M
( where specifically indicated.) s
5 181 M
( Loss Event Rate) s
5 126 M
(Floyd, et al. Expires: 18 May 2008 Section 5. [Page 8]) s
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24 24 translate
/pagenum 9 def
/fname (draft-ietf-dccp-ccid4-01.txt) def
/fdir () def
/ftail (draft-ietf-dccp-ccid4-01.txt) def
/user_header_p false def
%%EndPageSetup
5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
5 687 M
( As with CCID 3, the basic operation of CCID 4 centers around the) s
5 676 M
( calculation of a loss event rate: the number of loss events as a) s
5 665 M
( fraction of the number of packets transmitted, weighted over the last) s
5 654 M
( several loss intervals. For CCID 4, this loss event rate, a round-) s
5 643 M
( trip time estimate, and a nominal packet size of 1460 bytes are) s
5 632 M
( plugged into the TCP throughput equation, as specified in RFC 3448) s
5 621 M
( \(Section 3.1\) and [RFC4828].) s
5 599 M
( Because CCID 4 is intended for applications that send small packets,) s
5 588 M
( the allowed transmit rate derived from the TCP throughput equation is) s
5 577 M
( reduced by a factor that accounts for packet header size, as) s
5 566 M
( specified in Section 4.2 of [RFC4828]. The header size on data) s
5 555 M
( packets is estimated as 36 bytes \(20 bytes for the IP header, and 16) s
5 544 M
( bytes for the DCCP-Data header with 48-bit sequence numbers\). If the) s
5 533 M
( DCCP sender is sending N-byte data packets, the allowed transmit rate) s
5 522 M
( is reduced by N/\(N+36\). CCID 4 senders are limited to this fair) s
5 511 M
( rate. The header size would be 32 bytes instead of 36 bytes when) s
5 500 M
( 24-bit sequence numbers were used in the DCCP-Data header.) s
5 478 M
( As explained in Section 4.2 of [RFC4828], the actual header could be) s
5 467 M
( larger or smaller than the assumed value, due to IP or DCCP options,) s
5 456 M
( IPv6, IP tunnels, header compression, and the like. Because we are) s
5 445 M
( only aiming at rough fairness, and at a rough incentive for) s
5 434 M
( applications, the default use of a 32-byte or 36-byte header in the) s
5 423 M
( calculations of the header bandwidth is sufficient for both IPv4 and) s
5 412 M
( IPv6.) s
5 390 M
( If the sender is calculating the loss event rate itself, the loss) s
5 379 M
( event rate can be calculated using recent loss interval lengths) s
5 368 M
( reported by the receiver. Loss intervals are precisely defined in) s
5 357 M
( Section 6.1 of [RFC4342], with the modification in [RFC4828]) s
5 346 M
( \(Section 3\) for loss intervals of at most two round-trip times. In) s
5 335 M
( summary, a loss interval is up to 1 RTT of possibly lost or ECN-) s
5 324 M
( marked data packets, followed by an arbitrary number of non-dropped,) s
5 313 M
( non-marked data packets. The CCID 3 Loss Intervals option is used to) s
5 302 M
( report loss interval lengths; see Section 8.6.) s
5 280 M
( For loss intervals of at most two round-trip times, CCID 4 calculates) s
5 269 M
( the loss event rate for that interval by counting the number of) s
5 258 M
( packets lost or marked, as described in Section 4.4 of [RFC4828].) s
5 247 M
( Thus, for such a short loss interval with N data packets, including K) s
5 236 M
( lost or marked data packets, the loss interval length is calculated) s
5 225 M
( as N/K, instead as N. The Dropped Packets option is used to report) s
5 214 M
( K, the count of lost or marked data packets.) s
5 192 M
( Unlike CCID 3, the CCID 4 sender enforces a minimum interval of 10 ms) s
5 181 M
( between data packets, regardless of the allowed transmit rate. If) s
5 170 M
( operating system scheduling granularity makes this impractical, up to) s
5 126 M
(Floyd, et al. Expires: 18 May 2008 Section 5. [Page 9]) s
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%%BeginPageSetup
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24 24 translate
/pagenum 10 def
/fname (draft-ietf-dccp-ccid4-01.txt) def
/fdir () def
/ftail (draft-ietf-dccp-ccid4-01.txt) def
/user_header_p false def
%%EndPageSetup
5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
5 687 M
( one additional packet MAY be sent per timeslice, providing that no) s
5 676 M
( more than three packets are sent in any 30 ms interval.) s
5 654 M
( Other Congestion Control Mechanisms) s
5 632 M
( The other congestion control mechanisms such as slow-start, feedback) s
5 621 M
( packets, and the like are exactly as in CCID 3, and are described in) s
5 610 M
( the subsection on "Other Congestion Control Mechanisms" of Section 5) s
5 599 M
( in [RFC4342].) s
5 577 M
(5.1. Response to Idle and Application-limited Periods) s
5 555 M
( This is described in Section 5.1 of [RFC4342]. If Faster Restart is) s
5 544 M
( standardized in the IETF for TFRC [KFS07], then Faster Restart MAY be) s
5 533 M
( implemented in CCID4 without having to wait for an explicit update to) s
5 522 M
( this document.) s
5 500 M
(5.2. Response to Data Dropped and Slow Receiver) s
5 478 M
( This is described in Section 5.2 of [RFC4342].) s
5 456 M
(5.3. Packet Sizes) s
5 434 M
( CCID 4 is intended for applications that use a fixed small segment) s
5 423 M
( size, or that vary their segment size in response to congestion.) s
5 401 M
( The CCID 4 sender uses a segment size of 1460 bytes in the TCP) s
5 390 M
( throughput equation. This gives the CCID 4 sender roughly the same) s
5 379 M
( sending rate in bytes per second as a TFRC flow using 1460-byte) s
5 368 M
( segments but experiencing the same packet drop rate.) s
5 346 M
(6. Acknowledgements) s
5 324 M
( The acknowledgements are as specified in Section 6 of [RFC4342] with) s
5 313 M
( the exception of the Loss Interval lengths specified below.) s
5 291 M
(6.1. Loss Interval Definition) s
5 269 M
( The loss interval definition is as defined in Section 6.1 of) s
5 258 M
( [RFC4342], except as specified below. Section 6.1.1 of RFC 4342) s
5 247 M
( specifies that for all loss intervals except the first one, the data) s
5 236 M
( length equals the sequence length minus the number of non-data) s
5 225 M
( packets the sender transmitted during the loss interval, with a) s
5 214 M
( minimum data length of one packet. For TFRC-SP, for short loss) s
5 203 M
( intervals of at most two round-trip times, the loss interval length) s
5 192 M
( is computed not as the data length of the loss interval, but instead) s
5 181 M
( as the data length divided by the number of dropped or marked data) s
5 170 M
( packets.) s
5 126 M
(Floyd, et al. Expires: 18 May 2008 Section 6.1. [Page 10]) s
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%%BeginPageSetup
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24 24 translate
/pagenum 11 def
/fname (draft-ietf-dccp-ccid4-01.txt) def
/fdir () def
/ftail (draft-ietf-dccp-ccid4-01.txt) def
/user_header_p false def
%%EndPageSetup
5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
5 687 M
( Section 5.4 of RFC 4342 described when to use the most recent loss) s
5 676 M
( interval in the calculation of the average loss interval. [RFC4828]) s
5 665 M
( adds to this procedure the restriction that the most recent loss) s
5 654 M
( interval is only used in the calculation of the average loss interval) s
5 643 M
( if the most recent loss interval is greater than two round-trip) s
5 632 M
( times. The pseudocode is given in Section 3 of [RFC4828].) s
5 610 M
(6.2. Congestion Control on Acknowledgements) s
5 588 M
( The congestion control on acknowledgements is as specified in Section) s
5 577 M
( 6.2 of [RFC4342].) s
5 555 M
(6.3. Acknowledgements of Acknowledgements) s
5 533 M
( Procedures for the acknowledgement of acknowledgements are as) s
5 522 M
( specified in Section 6.3 of [RFC4342].) s
5 500 M
(6.4. Quiescence) s
5 478 M
( The procedure for detecting that the sender has gone quiescent is as) s
5 467 M
( specified in Section 6.4 of [RFC4342].) s
5 445 M
(7. Explicit Congestion Notification) s
5 423 M
( Procedures for the use of Explicit Congestion Notification \(ECN\) are) s
5 412 M
( as specified in Section 7 of [RFC4342].) s
5 390 M
(8. Options and Features) s
5 368 M
( CCID 4 can make use of DCCP's Ack Vector, Timestamp, Timestamp Echo,) s
5 357 M
( and Elapsed Time options, and its Send Ack Vector and ECN Incapable) s
5 346 M
( features. CCID 4 also imports the currently defined CCID 3-specific) s
5 335 M
( options and features [RFC4342], augmented by the Dropped Packets) s
5 324 M
( option specified in this document. Each CCID 4-specific option and) s
5 313 M
( feature contains the same data as the corresponding CCID 3 option or) s
5 302 M
( feature, and is interpreted in the same way, except as specified) s
5 291 M
( elsewhere in this document.) s
5 126 M
(Floyd, et al. Expires: 18 May 2008 Section 8. [Page 11]) s
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%%BeginPageSetup
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24 24 translate
/pagenum 12 def
/fname (draft-ietf-dccp-ccid4-01.txt) def
/fdir () def
/ftail (draft-ietf-dccp-ccid4-01.txt) def
/user_header_p false def
%%EndPageSetup
5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
5 687 M
( Option DCCP- Section) s
5 676 M
( Type Length Meaning Data? Reference) s
5 665 M
( ----- ------ ------- ----- ---------) s
5 654 M
( 128-191 Reserved) s
5 643 M
( 192 6 Loss Event Rate N 8.5) s
5 632 M
( 193 variable Loss Intervals N 8.6) s
5 621 M
( 194 6 Receive Rate N 8.3) s
5 610 M
( 195 variable Dropped Packets N 8.7) s
5 599 M
( 196-255 Reserved) s
5 577 M
( Table 1: DCCP CCID 4 Options) s
5 566 M
( The "DCCP-Data?" column indicates that all currently defined) s
5 555 M
( CCID 4-specific options MUST be ignored when they occur on DCCP-Data) s
5 544 M
( packets.) s
5 522 M
( As with CCID 3, the following CCID-specific features are also) s
5 511 M
( defined.) s
5 489 M
( Rec'n Initial Section) s
5 478 M
( Number Meaning Rule Value Req'd Reference) s
5 467 M
( ------ ------- ----- ----- ----- ---------) s
5 456 M
( 128-191 Reserved) s
5 445 M
( 192 Send Loss Event Rate SP 0 N 8.4) s
5 434 M
( 193-255 Reserved) s
5 412 M
( Table 2: DCCP CCID 4 Feature Numbers) s
5 390 M
( More information is available in Section 8 of [RFC4342].) s
5 368 M
(8.1. Window Counter Value) s
5 346 M
( The use of the Window Counter Value in the DCCP generic header's) s
5 335 M
( CCVal field is as specified in Section 8.1 of [RFC4342]. In addition) s
5 324 M
( to their use described in CCID 3, the CCVal counters are used by the) s
5 313 M
( receiver in CCID 4 to determine when the length of a loss interval is) s
5 302 M
( at most two round-trip times. None of these procedures require the) s
5 291 M
( receiver to maintain an explicit estimate of the round-trip time.) s
5 280 M
( However, Section 8.1 of [RFC4342] gives a procedure that implementors) s
5 269 M
( may use if they wish to keep such an RTT estimate using CCVal.) s
5 247 M
(8.2. Elapsed Time Options) s
5 225 M
( The use of the Elapsed Time option is defined in Section 8.2 of) s
5 214 M
( [RFC4342].) s
5 126 M
(Floyd, et al. Expires: 18 May 2008 Section 8.2. [Page 12]) s
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%%BeginPageSetup
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24 24 translate
/pagenum 13 def
/fname (draft-ietf-dccp-ccid4-01.txt) def
/fdir () def
/ftail (draft-ietf-dccp-ccid4-01.txt) def
/user_header_p false def
%%EndPageSetup
5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
5 687 M
(8.3. Receive Rate Option) s
5 665 M
( The Receive Rate option is as specified in Section 8.3 of [RFC4342].) s
5 643 M
(8.4. Send Loss Event Rate Feature) s
5 621 M
( The Send Loss Event Rate feature is as defined in Section 8.4 of) s
5 610 M
( [RFC4342].) s
5 588 M
( See [RFC3448], Section 5 and [RFC4828], Section 4.4 for a normative) s
5 577 M
( calculation of the loss event rate. Section 4.4 of [RFC4828]) s
5 566 M
( modifies the calculation of the loss interval size for loss intervals) s
5 555 M
( of at most two round-trip times.) s
5 533 M
( If the CCID 4 receiver is using the Loss Event Rate option, the) s
5 522 M
( receiver needs to be able to determine if a loss interval is short,) s
5 511 M
( of at most two round-trip times. The receiver can heuristically) s
5 500 M
( detect a short loss interval by using the Window Counter in arriving) s
5 489 M
( data packets. The sender increases the Window Counter by 1 every) s
5 478 M
( quarter of a round-trip time, with the caveat that the Window Counter) s
5 467 M
( is never increased by more than five, modulo 16, from one data packet) s
5 456 M
( to the next. Using the Window Counter to detect loss intervals of at) s
5 445 M
( most two round-trip times could result in some false positives, with) s
5 434 M
( some longer loss intervals incorrectly identified as short ones. For) s
5 423 M
( example, if the loss interval contained data packets with only two) s
5 412 M
( Window Counter values, say, k and k+5, then the receiver could not) s
5 401 M
( tell if the loss interval was at most two round-trip times long or) s
5 390 M
( not. Similarly, if the sender sent data packets with Window Counter) s
5 379 M
( values of 4, 8, 12, 0, 5, but the packets with Window Counter values) s
5 368 M
( of 8, 12, and 0 were lost in the network, then the receiver would) s
5 357 M
( only receive data packets with Window Counter values of 4 and 5, and) s
5 346 M
( would incorrectly infer that the loss interval was at most two round-) s
5 335 M
( trip times.) s
5 302 M
(8.5. Loss Event Rate Option) s
5 280 M
( The Loss Event Rate option is as specified in Section 8.5 of) s
5 269 M
( [RFC4342].) s
5 247 M
( See [RFC3448] \(Section 5\) and [RFC4828] for a normative calculation) s
5 236 M
( of the loss event rate.) s
5 214 M
(8.6. Loss Intervals Option) s
5 192 M
( The Loss Intervals option is as specified in Section 8.6 of) s
5 181 M
( [RFC4342].) s
5 126 M
(Floyd, et al. Expires: 18 May 2008 Section 8.6. [Page 13]) s
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%%BeginPageSetup
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24 24 translate
/pagenum 14 def
/fname (draft-ietf-dccp-ccid4-01.txt) def
/fdir () def
/ftail (draft-ietf-dccp-ccid4-01.txt) def
/user_header_p false def
%%EndPageSetup
5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
5 687 M
(8.7. Dropped Packets Option) s
5 665 M
( This section describes the Dropped Packets option, a mechanism for) s
5 654 M
( reporting the number of lost and marked packets per loss interval.) s
5 643 M
( By reporting both the Loss Intervals and Dropped Packets options on) s
5 632 M
( the feedback packets, the receiver gives the sender sufficient) s
5 621 M
( information to calculate the loss event rate, or to verify the) s
5 610 M
( calculation of the reported loss event rate, if the sender so) s
5 599 M
( desires.) s
5 577 M
( The core information reported by CCID 4 receivers is a list of recent) s
5 566 M
( loss intervals, where a loss interval begins with a lost or ECN-) s
5 555 M
( marked data packet; continues with at most one round-trip time's) s
5 544 M
( worth of packets that may or may not be lost or marked; and completes) s
5 533 M
( with an arbitrarily long series of non-dropped, non-marked data) s
5 522 M
( packets. Loss intervals model the congestion behavior of TCP NewReno) s
5 511 M
( senders, which reduce their sending rate at most once per window of) s
5 500 M
( data packets. Consequently, the number of packets lost in a loss) s
5 489 M
( interval is not important for either TCP's or TFRC's congestion) s
5 478 M
( response. CCID 3's Loss Intervals option reports the length of each) s
5 467 M
( loss interval's lossy part, not the number of packets that were) s
5 456 M
( actually lost or marked in that lossy part.) s
5 434 M
( However, for computing the loss event rate for periods that include) s
5 423 M
( short loss intervals the TFRC-SP sender needs to know the number of) s
5 412 M
( packets lost or marked in a loss interval, over and above the length) s
5 401 M
( of the loss interval in packets. The Dropped Packets option, a) s
5 390 M
( CCID 4-specific option, reports this information. Together with the) s
5 379 M
( existing Loss Intervals option, the Dropped Packets option allows the) s
5 368 M
( CCID 4 sender to discover exactly how many packets were dropped from) s
5 357 M
( each loss interval. The receiver reports the number of lost or) s
5 346 M
( marked packets in its recently observed loss intervals using the) s
5 335 M
( Dropped Packets option.) s
5 313 M
( The Dropped Packets Option is specified as follows:) s
5 291 M
( +--------+--------+-------...-------+--------+-------) s
5 280 M
( |11000011| Length | Drop Count | More Drop Counts...) s
5 269 M
( +--------+--------+-------...-------+--------+-------) s
5 258 M
( Type=195 3 bytes) s
5 236 M
( The Dropped Packets option contains information about one to 84) s
5 225 M
( consecutive loss intervals, always including the most recent loss) s
5 214 M
( interval. As with the Loss Intervals option, intervals are listed in) s
5 203 M
( reverse chronological order. Should more than 84 loss intervals need) s
5 192 M
( to be reported, multiple Dropped Packets options can be sent; the) s
5 181 M
( second option begins where the first left off, and so forth.) s
5 126 M
(Floyd, et al. Expires: 18 May 2008 Section 8.7. [Page 14]) s
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%%BeginPageSetup
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24 24 translate
/pagenum 15 def
/fname (draft-ietf-dccp-ccid4-01.txt) def
/fdir () def
/ftail (draft-ietf-dccp-ccid4-01.txt) def
/user_header_p false def
%%EndPageSetup
5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
5 687 M
( One Drop Count is specified per loss interval. Drop Count is a) s
5 676 M
( 24-bit number that equals the number of packets lost or received ECN-) s
5 665 M
( marked during the corresponding loss interval. By definition, this) s
5 654 M
( number MUST NOT exceed the corresponding loss interval's Loss Length.) s
5 632 M
( CCID 4 receivers MUST report Dropped Packets options with every) s
5 621 M
( feedback packet. Any packet containing a Loss Intervals option MUST) s
5 610 M
( also contain a Dropped Packets option covering the same loss) s
5 599 M
( intervals. If a feedback packet does not include a relevant Dropped) s
5 588 M
( Packets option, and the CCID 4 sender is computing the loss event) s
5 577 M
( rate itself, the sender MUST treat the relevant loss intervals' Drop) s
5 566 M
( Counts as equal to the corresponding Loss Lengths, as specified) s
5 555 M
( below. This conservative assumption leads to the minimum send rate) s
5 544 M
( for the corresponding loss intervals.) s
5 522 M
( Consider a CCID 4 receiver. As specified in Section 8.6.1 of RFC) s
5 511 M
( 4342, the receiver sends the Loss Intervals option for all intervals) s
5 500 M
( that have not been acknowledged by the sender. When this receiver) s
5 489 M
( sends a feedback packet containing information about the N most) s
5 478 M
( recent loss intervals \(packaged in one or more Loss Intervals) s
5 467 M
( options\), then the receiver includes on the same feedback packet one) s
5 456 M
( or more Dropped Packets options covering exactly those N loss) s
5 445 M
( intervals. CCID 4 senders MUST ignore Drop Counts information for) s
5 434 M
( loss intervals not covered by a Loss Intervals option on the same) s
5 423 M
( feedback packet. Conversely, a CCID 4 sender might want to) s
5 412 M
( interpolate Drop Counts information for a loss interval not covered) s
5 401 M
( by any Dropped Packets options; such a sender MUST use the) s
5 390 M
( corresponding loss interval's Loss Length as its Drop Count.) s
5 368 M
( Each loss interval's Drop Count MUST by definition be less than or) s
5 357 M
( equal to its Loss Length. A Drop Count that exceeds the) s
5 346 M
( corresponding Loss Length MUST be treated as equal to the Loss) s
5 335 M
( Length.) s
5 313 M
(8.7.1. Example) s
5 291 M
( Consider the following sequence of packets, where "-" represents a) s
5 280 M
( safely delivered packet and "*" represents a lost or marked packet.) s
5 269 M
( This sequence is repeated from [RFC4342].) s
5 247 M
( Sequence) s
5 236 M
( Numbers: 0 10 20 30 40 44) s
5 225 M
( | | | | | |) s
5 214 M
( ----------*--------***-*--------*----------*-) s
5 192 M
( Assuming that packet 43 was lost, not marked, this sequence might be) s
5 181 M
( divided into loss intervals as follows:) s
5 126 M
(Floyd, et al. Expires: 18 May 2008 Section 8.7.1. [Page 15]) s
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/pagenum 16 def
/fname (draft-ietf-dccp-ccid4-01.txt) def
/fdir () def
/ftail (draft-ietf-dccp-ccid4-01.txt) def
/user_header_p false def
%%EndPageSetup
5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
5 687 M
( 0 10 20 30 40 44) s
5 676 M
( | | | | | |) s
5 665 M
( ----------*--------***-*--------*----------*-) s
5 654 M
( \\________/\\_______/\\___________/\\_________/) s
5 643 M
( L0 L1 L2 L3) s
5 621 M
( A Loss Intervals option sent on a packet with Acknowledgement Number) s
5 610 M
( 44 to acknowledge this set of loss intervals might contain the bytes) s
5 599 M
( 193,39,2, 0,0,10, 128,0,1, 0,0,10, 0,0,8, 0,0,5, 0,0,10, 0,0,8,) s
5 588 M
( 0,0,1, 0,0,8, 0,0,10, 128,0,0, 0,0,15; for interpretation of this) s
5 577 M
( option, see [RFC4342]. A Dropped Packets option sent in tandem on) s
5 566 M
( this packet would contain the bytes 195,14, 0,0,1, 0,0,4, 0,0,1,) s
5 555 M
( 0,0,0. This is interpreted as follows.) s
5 533 M
( 195 The Dropped Packets option number.) s
5 511 M
( 14 The length of the option, including option type and length bytes.) s
5 500 M
( This option contains information about \(14 - 2\)/3 = 4 loss) s
5 489 M
( intervals. Note that the two most recent sequence numbers are) s
5 478 M
( not yet part of any loss interval -- the Loss Intervals option) s
5 467 M
( includes them in its Skip Length -- and are thus not included in) s
5 456 M
( the Dropped Packets option.) s
5 434 M
( 0,0,1) s
5 423 M
( These bytes define the Drop Count for L3, which is 1. As) s
5 412 M
( required, the Drop Count is less than or equal to L3's Loss) s
5 401 M
( Length, which is also 1.) s
5 379 M
( 0,0,4) s
5 368 M
( The Drop Count for L2 is 4.) s
5 346 M
( 0,0,1) s
5 335 M
( The Drop Count for L1 is 1.) s
5 313 M
( 0,0,0) s
5 302 M
( Finally, the Drop Count for L0 is 0.) s
5 280 M
(9. Verifying Congestion Control Compliance With ECN) s
5 258 M
( Verifying congestion control compliance with ECN is as discussed in) s
5 247 M
( Section 9 of [RFC4342].) s
5 225 M
(9.1. Verifying the ECN Nonce Echo) s
5 203 M
( Procedures for verifying the ECN Nonce Echo are as specified in) s
5 192 M
( Section 9.1 of [RFC4342].) s
5 126 M
(Floyd, et al. Expires: 18 May 2008 Section 9.1. [Page 16]) s
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24 24 translate
/pagenum 17 def
/fname (draft-ietf-dccp-ccid4-01.txt) def
/fdir () def
/ftail (draft-ietf-dccp-ccid4-01.txt) def
/user_header_p false def
%%EndPageSetup
5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
5 687 M
(9.2. Verifying the Reported Loss Intervals and Loss Event Rate) s
5 665 M
( Section 9.2 of [RFC4342] discusses the sender's possible verification) s
5 654 M
( of loss intervals and loss event rate information reported by the) s
5 643 M
( receiver.) s
5 621 M
(10. Implementation Issues) s
5 599 M
(10.1. Timestamp Usage) s
5 577 M
( The use of the Timestamp option is as discussed in Section 10.1 of) s
5 566 M
( [RFC4342].) s
5 544 M
(10.2. Determining Loss Events at the Receiver) s
5 522 M
( The use of the window counter by the receiver to determine if) s
5 511 M
( multiple lost packets belong to the same loss event is as described) s
5 500 M
( in Section 10.2 of [RFC4342].) s
5 478 M
(10.3. Sending Feedback Packets) s
5 456 M
( The procedure for sending feedback packets is as described in Section) s
5 445 M
( 10.3 of [RFC4342].) s
5 412 M
(11. Security Considerations) s
5 390 M
( Security considerations include those discussed in Section 11 of) s
5 379 M
( [RFC4342]. There are no new security considerations introduced by) s
5 368 M
( CCID 4.) s
5 346 M
(12. IANA Considerations) s
5 324 M
( This specification defines the value 4 in the DCCP CCID namespace) s
5 313 M
( managed by IANA.) s
5 291 M
( CCID 4 also uses three sets of numbers whose values should be) s
5 280 M
( allocated by IANA, namely CCID 4-specific Reset Codes, option types,) s
5 269 M
( and feature numbers. This document makes no particular allocations) s
5 258 M
( from the Reset Code range, except for experimental and testing use) s
5 247 M
( [RFC3692]. We refer to the Standards Action policy outlined in) s
5 236 M
( [RFC2434].) s
5 203 M
(12.1. Reset Codes) s
5 181 M
( Each entry in the DCCP CCID 4 Reset Code registry contains a) s
5 170 M
( CCID 4-specific Reset Code, which is a number in the range 128-255; a) s
5 126 M
(Floyd, et al. Expires: 18 May 2008 Section 12.1. [Page 17]) s
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24 24 translate
/pagenum 18 def
/fname (draft-ietf-dccp-ccid4-01.txt) def
/fdir () def
/ftail (draft-ietf-dccp-ccid4-01.txt) def
/user_header_p false def
%%EndPageSetup
5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
5 687 M
( short description of the Reset Code; and a reference to the RFC) s
5 676 M
( defining the Reset Code. Reset Codes 184-190 and 248-254 are) s
5 665 M
( permanently reserved for experimental and testing use. The remaining) s
5 654 M
( Reset Codes -- 128-183, 191-247, and 255 -- are currently reserved,) s
5 643 M
( and should be allocated with the Standards Action policy, which) s
5 632 M
( requires IESG review and approval and standards-track IETF RFC) s
5 621 M
( publication.) s
5 599 M
(12.2. Option Types) s
5 577 M
( Each entry in the DCCP CCID 4 option type registry contains a) s
5 566 M
( CCID 4-specific option type, which is a number in the range 128-255;) s
5 555 M
( the name of the option, such as "Loss Intervals"; and a reference to) s
5 544 M
( the RFC defining the option type. The registry is initially) s
5 533 M
( populated using the values in Table 1, in Section 8. This includes) s
5 522 M
( the value 195 allocated for the Dropped Packets option. This) s
5 511 M
( document allocates option types 192-195, and option types 184-190 and) s
5 500 M
( 248-254 are permanently reserved for experimental and testing use.) s
5 489 M
( The remaining option types -- 128-183, 191, 196-247, and 255 -- are) s
5 478 M
( currently reserved, and should be allocated with the Standards Action) s
5 467 M
( policy, which requires IESG review and approval and standards-track) s
5 456 M
( IETF RFC publication.) s
5 423 M
(12.3. Feature Numbers) s
5 401 M
( Each entry in the DCCP CCID 4 feature number registry contains a) s
5 390 M
( CCID 4-specific feature number, which is a number in the range) s
5 379 M
( 128-255; the name of the feature, such as "Send Loss Event Rate"; and) s
5 368 M
( a reference to the RFC defining the feature number. The registry is) s
5 357 M
( initially populated using the values in Table 2, in Section 8. This) s
5 346 M
( document allocates feature number 192, and feature numbers 184-190) s
5 335 M
( and 248-254 are permanently reserved for experimental and testing) s
5 324 M
( use. The remaining feature numbers -- 128-183, 191, 193-247, and 255) s
5 313 M
( -- are currently reserved, and should be allocated with the Standards) s
5 302 M
( Action policy, which requires IESG review and approval and standards-) s
5 291 M
( track IETF RFC publication.) s
5 269 M
(13. Thanks) s
5 247 M
( We thank Gorry Fairhurst, Ian McDonald, Gerrit Renker, and Leandro) s
5 236 M
( Sales for feedback on this document.) s
5 214 M
(Normative References) s
5 192 M
( [RFC2119] S. Bradner. Key Words For Use in RFCs to Indicate) s
5 181 M
( Requirement Levels. RFC 2119.) s
5 126 M
(Floyd, et al. Expires: 18 May 2008 [Page 18]) s
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24 24 translate
/pagenum 19 def
/fname (draft-ietf-dccp-ccid4-01.txt) def
/fdir () def
/ftail (draft-ietf-dccp-ccid4-01.txt) def
/user_header_p false def
%%EndPageSetup
5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
5 687 M
( [RFC2434] T. Narten and H. Alvestrand. Guidelines for Writing) s
5 676 M
( an IANA Considerations Section in RFCs. RFC 2434.) s
5 654 M
( [RFC3448] M. Handley, S. Floyd, J. Padhye, and J. Widmer, TCP) s
5 643 M
( Friendly Rate Control \(TFRC\): Protocol Specification,) s
5 632 M
( RFC 3448, Proposed Standard, January 2003.) s
5 610 M
( [RFC3448Errat] RFC Errata for RFC 3448, URL "http://www.rfc-) s
5 599 M
( editor.org/errata.php".) s
5 577 M
( [RFC3692] T. Narten. Assigning Experimental and Testing Numbers) s
5 566 M
( Considered Useful. RFC 3692.) s
5 544 M
( [RFC4340] Kohler, E., Handley, M., and S. Floyd. Datagram) s
5 533 M
( Congestion Control Protocol \(DCCP\), RFC 4340, March) s
5 522 M
( 2006.) s
5 500 M
( [RFC4342] Floyd, S., Kohler, E., and J. Padhye. Profile for) s
5 489 M
( Datagram Congestion Control Protocol \(DCCP\) Congestion) s
5 478 M
( Control ID 3: TCP-Friendly Rate Control \(TFRC\), RFC) s
5 467 M
( 4342, March 2006.) s
5 445 M
( [RFC4342Errat] RFC Errata for RFC 4342, URL "http://www.rfc-) s
5 434 M
( editor.org/errata.php".) s
5 412 M
( [RFC4828] S. Floyd and E. Kohler. TCP Friendly Rate Control) s
5 401 M
( \(TFRC\): the Small-Packet \(SP\) Variant. RFC 4828,) s
5 390 M
( April 2007.) s
5 368 M
(Informative References) s
5 346 M
( [KFS07] Kohler, E., S. Floyd, and A. Sathiaseelan, Faster) s
5 335 M
( Restart for TCP Friendly Rate Control \(TFRC\),) s
5 324 M
( Internet-draft draft-ietf-dccp-tfrc-faster-) s
5 313 M
( restart-04.txt, work-in-progress, September 2007.) s
5 291 M
( [RFC3448bis] M. Handley, S. Floyd, J. Padhye, and J. Widmer, TCP) s
5 280 M
( Friendly Rate Control \(TFRC\): Protocol Specification,) s
5 269 M
( internet-draft draft-ietf-dccp-rfc3448bis-02.txt,) s
5 258 M
( work-in-progress, July 2007.) s
5 126 M
(Floyd, et al. Expires: 18 May 2008 [Page 19]) s
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/pagenum 20 def
/fname (draft-ietf-dccp-ccid4-01.txt) def
/fdir () def
/ftail (draft-ietf-dccp-ccid4-01.txt) def
/user_header_p false def
%%EndPageSetup
5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
5 687 M
(Authors' Addresses) s
5 665 M
( Sally Floyd) s
5 654 M
( ICSI Center for Internet Research) s
5 643 M
( 1947 Center Street, Suite 600) s
5 632 M
( Berkeley, CA 94704) s
5 621 M
( USA) s
5 599 M
( Email: floyd@icir.org) s
5 577 M
( Eddie Kohler) s
5 566 M
( 4531C Boelter Hall) s
5 555 M
( UCLA Computer Science Department) s
5 544 M
( Los Angeles, CA 90095) s
5 533 M
( USA) s
5 511 M
( Email: kohler@cs.ucla.edu) s
5 489 M
(Full Copyright Statement) s
5 467 M
( Copyright \(C\) The IETF Trust \(2007\).) s
5 445 M
( This document is subject to the rights, licenses and restrictions) s
5 434 M
( contained in BCP 78, and except as set forth therein, the authors) s
5 423 M
( retain all their rights.) s
5 401 M
( This document and the information contained herein are provided on an) s
5 390 M
( "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS) s
5 379 M
( OR IS SPONSORED BY \(IF ANY\), THE INTERNET SOCIETY, THE IETF TRUST AND) s
5 368 M
( THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS) s
5 357 M
( OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF) s
5 346 M
( THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED) s
5 335 M
( WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.) s
5 313 M
(Intellectual Property) s
5 291 M
( The IETF takes no position regarding the validity or scope of any) s
5 280 M
( Intellectual Property Rights or other rights that might be claimed to) s
5 269 M
( pertain to the implementation or use of the technology described in) s
5 258 M
( this document or the extent to which any license under such rights) s
5 247 M
( might or might not be available; nor does it represent that it has) s
5 236 M
( made any independent effort to identify any such rights. Information) s
5 225 M
( on the procedures with respect to rights in RFC documents can be) s
5 214 M
( found in BCP 78 and BCP 79.) s
5 192 M
( Copies of IPR disclosures made to the IETF Secretariat and any) s
5 181 M
( assurances of licenses to be made available, or the result of an) s
5 170 M
( attempt made to obtain a general license or permission for the use of) s
5 126 M
(Floyd, et al. Expires: 18 May 2008 [Page 20]) s
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/pagenum 21 def
/fname (draft-ietf-dccp-ccid4-01.txt) def
/fdir () def
/ftail (draft-ietf-dccp-ccid4-01.txt) def
/user_header_p false def
%%EndPageSetup
5 720 M
(INTERNET-DRAFT Profile for DCCP's CCID-4 November 2007) s
5 687 M
( such proprietary rights by implementers or users of this) s
5 676 M
( specification can be obtained from the IETF on-line IPR repository at) s
5 665 M
( http://www.ietf.org/ipr.) s
5 643 M
( The IETF invites any interested party to bring to its attention any) s
5 632 M
( copyrights, patents or patent applications, or other proprietary) s
5 621 M
( rights that may cover technology that may be required to implement) s
5 610 M
( this standard. Please address the information to the IETF at ietf-) s
5 599 M
( ipr@ietf.org.) s
5 577 M
(Acknowledgement) s
5 555 M
( Funding for the RFC Editor function is provided by the IETF) s
5 544 M
( Administrative Support Activity \(IASA\).) s
5 126 M
(Floyd, et al. Expires: 18 May 2008 [Page 21]) s
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24 24 translate
/pagenum 22 def
/fname (draft-ietf-dccp-ccid4-01.txt) def
/fdir () def
/ftail (draft-ietf-dccp-ccid4-01.txt) def
/user_header_p false def
%%EndPageSetup
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%%Trailer
%%Pages: 22
%%DocumentNeededResources: font Courier-Bold Courier
%%EOF
| PAFTECH AB 2003-2026 | 2026-04-22 21:01:11 |