One document matched: draft-ietf-dccp-ccid2-02.ps

%!PS-Adobe-3.0
%%Creator: groff version 1.18.1
%%CreationDate: Sat May 10 16:14:38 2003
%%DocumentNeededResources: font Courier-Bold
%%+ font Times-Bold
%%+ font Times-Roman
%%+ font Courier
%%DocumentSuppliedResources: procset grops 1.18 1
%%Pages: 10
%%PageOrder: Ascend
%%Orientation: Portrait
%%EndComments
%%BeginProlog
%%BeginResource: procset grops 1.18 1
/setpacking where{
pop
currentpacking
true setpacking
}if
/grops 120 dict dup begin
/SC 32 def
/A/show load def
/B{0 SC 3 -1 roll widthshow}bind def
/C{0 exch ashow}bind def
/D{0 exch 0 SC 5 2 roll awidthshow}bind def
/E{0 rmoveto show}bind def
/F{0 rmoveto 0 SC 3 -1 roll widthshow}bind def
/G{0 rmoveto 0 exch ashow}bind def
/H{0 rmoveto 0 exch 0 SC 5 2 roll awidthshow}bind def
/I{0 exch rmoveto show}bind def
/J{0 exch rmoveto 0 SC 3 -1 roll widthshow}bind def
/K{0 exch rmoveto 0 exch ashow}bind def
/L{0 exch rmoveto 0 exch 0 SC 5 2 roll awidthshow}bind def
/M{rmoveto show}bind def
/N{rmoveto 0 SC 3 -1 roll widthshow}bind def
/O{rmoveto 0 exch ashow}bind def
/P{rmoveto 0 exch 0 SC 5 2 roll awidthshow}bind def
/Q{moveto show}bind def
/R{moveto 0 SC 3 -1 roll widthshow}bind def
/S{moveto 0 exch ashow}bind def
/T{moveto 0 exch 0 SC 5 2 roll awidthshow}bind def
/SF{
findfont exch
[exch dup 0 exch 0 exch neg 0 0]makefont
dup setfont
[exch/setfont cvx]cvx bind def
}bind def
/MF{
findfont
[5 2 roll
0 3 1 roll
neg 0 0]makefont
dup setfont
[exch/setfont cvx]cvx bind def
}bind def
/level0 0 def
/RES 0 def
/PL 0 def
/LS 0 def
/MANUAL{
statusdict begin/manualfeed true store end
}bind def
/PLG{
gsave newpath clippath pathbbox grestore
exch pop add exch pop
}bind def
/BP{
/level0 save def
1 setlinecap
1 setlinejoin
72 RES div dup scale
LS{
90 rotate
}{
0 PL translate
}ifelse
1 -1 scale
}bind def
/EP{
level0 restore
showpage
}bind def
/DA{
newpath arcn stroke
}bind def
/SN{
transform
.25 sub exch .25 sub exch
round .25 add exch round .25 add exch
itransform
}bind def
/DL{
SN
moveto
SN
lineto stroke
}bind def
/DC{
newpath 0 360 arc closepath
}bind def
/TM matrix def
/DE{
TM currentmatrix pop
translate scale newpath 0 0 .5 0 360 arc closepath
TM setmatrix
}bind def
/RC/rcurveto load def
/RL/rlineto load def
/ST/stroke load def
/MT/moveto load def
/CL/closepath load def
/Fr{
setrgbcolor fill
}bind def
/Fk{
setcmykcolor fill
}bind def
/Fg{
setgray fill
}bind def
/FL/fill load def
/LW/setlinewidth load def
/Cr/setrgbcolor load def
/Ck/setcmykcolor load def
/Cg/setgray load def
/RE{
findfont
dup maxlength 1 index/FontName known not{1 add}if dict begin
{
1 index/FID ne{def}{pop pop}ifelse
}forall
/Encoding exch def
dup/FontName exch def
currentdict end definefont pop
}bind def
/DEFS 0 def
/EBEGIN{
moveto
DEFS begin
}bind def
/EEND/end load def
/CNT 0 def
/level1 0 def
/PBEGIN{
/level1 save def
translate
div 3 1 roll div exch scale
neg exch neg exch translate
0 setgray
0 setlinecap
1 setlinewidth
0 setlinejoin
10 setmiterlimit
[]0 setdash
/setstrokeadjust where{
pop
false setstrokeadjust
}if
/setoverprint where{
pop
false setoverprint
}if
newpath
/CNT countdictstack def
userdict begin
/showpage{}def
}bind def
/PEND{
clear
countdictstack CNT sub{end}repeat
level1 restore
}bind def
end def
/setpacking where{
pop
setpacking
}if
%%EndResource
%%IncludeResource: font Courier-Bold
%%IncludeResource: font Times-Bold
%%IncludeResource: font Times-Roman
%%IncludeResource: font Courier
grops begin/DEFS 1 dict def DEFS begin/u{.001 mul}bind def end/RES 72
def/PL 792 def/LS false def/ENC0[/asciicircum/asciitilde/Scaron/Zcaron
/scaron/zcaron/Ydieresis/trademark/quotesingle/Euro/.notdef/.notdef
/.notdef/.notdef/.notdef/.notdef/.notdef/.notdef/.notdef/.notdef/.notdef
/.notdef/.notdef/.notdef/.notdef/.notdef/.notdef/.notdef/.notdef/.notdef
/.notdef/.notdef/space/exclam/quotedbl/numbersign/dollar/percent
/ampersand/quoteright/parenleft/parenright/asterisk/plus/comma/hyphen
/period/slash/zero/one/two/three/four/five/six/seven/eight/nine/colon
/semicolon/less/equal/greater/question/at/A/B/C/D/E/F/G/H/I/J/K/L/M/N/O
/P/Q/R/S/T/U/V/W/X/Y/Z/bracketleft/backslash/bracketright/circumflex
/underscore/quoteleft/a/b/c/d/e/f/g/h/i/j/k/l/m/n/o/p/q/r/s/t/u/v/w/x/y
/z/braceleft/bar/braceright/tilde/.notdef/quotesinglbase/guillemotleft
/guillemotright/bullet/florin/fraction/perthousand/dagger/daggerdbl
/endash/emdash/ff/fi/fl/ffi/ffl/dotlessi/dotlessj/grave/hungarumlaut
/dotaccent/breve/caron/ring/ogonek/quotedblleft/quotedblright/oe/lslash
/quotedblbase/OE/Lslash/.notdef/exclamdown/cent/sterling/currency/yen
/brokenbar/section/dieresis/copyright/ordfeminine/guilsinglleft
/logicalnot/minus/registered/macron/degree/plusminus/twosuperior
/threesuperior/acute/mu/paragraph/periodcentered/cedilla/onesuperior
/ordmasculine/guilsinglright/onequarter/onehalf/threequarters
/questiondown/Agrave/Aacute/Acircumflex/Atilde/Adieresis/Aring/AE
/Ccedilla/Egrave/Eacute/Ecircumflex/Edieresis/Igrave/Iacute/Icircumflex
/Idieresis/Eth/Ntilde/Ograve/Oacute/Ocircumflex/Otilde/Odieresis
/multiply/Oslash/Ugrave/Uacute/Ucircumflex/Udieresis/Yacute/Thorn
/germandbls/agrave/aacute/acircumflex/atilde/adieresis/aring/ae/ccedilla
/egrave/eacute/ecircumflex/edieresis/igrave/iacute/icircumflex/idieresis
/eth/ntilde/ograve/oacute/ocircumflex/otilde/odieresis/divide/oslash
/ugrave/uacute/ucircumflex/udieresis/yacute/thorn/ydieresis]def
/Courier@0 ENC0/Courier RE/Times-Roman@0 ENC0/Times-Roman RE
/Times-Bold@0 ENC0/Times-Bold RE/Courier-Bold@0 ENC0/Courier-Bold RE
%%EndProlog
%%Page: 1 1
%%BeginPageSetup
BP
%%EndPageSetup
/F0 10/Courier-Bold@0 SF(Internet Engineering Task Force)72 85 Q 275.999
(INTERNET-DRAFT Sally)72 98 R(Floyd)6 E 191.999
(draft-ietf-dccp-ccid2-02.ps Eddie)72 111 R(Kohler)6 E(ICIR)479.999 124
Q(10 May 2003)437.999 137 Q(Expires: November 2003)371.999 150 Q/F1 14
/Times-Bold@0 SF(Pr)159.333 175 Q(o\214le f)-.252 E
(or DCCP Congestion Contr)-.35 E(ol ID 2:)-.252 E(TCP-lik)200.696 188 Q
3.5(eC)-.14 G(ongestion Contr)-3.5 E(ol)-.252 E/F2 11/Times-Bold@0 SF
(Status of this Document)72 233 Q/F3 11/Times-Roman@0 SF(This document \
is an Internet-Draft and is in full conformance with all pro)100.8 249.6
Q(visions of Section)-.165 E(10 of [RFC 2026].)100.8 262.6 Q
(Internet-Drafts are w)5.5 E
(orking documents of the Internet Engineering T)-.11 E(ask)-.88 E -.165
(Fo)100.8 275.6 S(rce \(IETF\), its areas, and its w).165 E
(orking groups.)-.11 E(Note that other groups may also distrib)5.5 E
(ute)-.22 E -.11(wo)100.8 288.6 S(rking documents as Internet-Drafts.)
.11 E(Internet-Drafts are draft documents v)100.8 314.6 Q
(alid for a maximum of six months and may be)-.275 E
(updated, replaced, or obsoleted by other documents at an)100.8 327.6 Q
2.75(yt)-.165 G(ime. It is inappropriate to use)-2.75 E
(Internet-Drafts as reference material or to cite them other than as "w)
100.8 340.6 Q(ork in progress.")-.11 E
(The list of current Internet-Drafts can be accessed at http://www)100.8
366.6 Q(.ietf.or)-.715 E(g/ietf/1id-)-.198 E(abstracts.txt)100.8 379.6 Q
(The list of Internet-Draft Shado)100.8 405.6 Q 2.75(wD)-.275 G
(irectories can be accessed at)-2.75 E(http://www)100.8 418.6 Q
(.ietf.or)-.715 E(g/shado)-.198 E -.715(w.)-.275 G(html).715 E F2
(Abstract)267.534 437.6 Q F3(This document contains the pro\214le for C\
ongestion Control Identi\214er 2, TCP-lik)97 460.2 Q(e)-.11 E(Congestio\
n Control, in the Datagram Congestion Control Protocol \(DCCP\) [DCCP].)
97 473.2 Q(DCCP implements a congestion-controlled, unreliable \215o)97
486.2 Q 2.75(wo)-.275 G 2.75(fd)-2.75 G(atagrams suitable for)-2.75 E
(use by applications such as streaming media. The TCP-lik)97 499.2 Q
2.75(eC)-.11 G(ongestion Control CCID)-2.75 E(is used by senders who ar\
e able to adapt to the abrupt changes in the congestion)97 512.2 Q
(windo)97 525.2 Q 2.75(wt)-.275 G(ypical of TCP')-2.75 E 2.75(sA)-.605 G
(IMD \(Additi)-2.75 E .33 -.165(ve I)-.275 H(ncrease Multiplicati).165 E
.33 -.165(ve D)-.275 H(ecrease\)).165 E(congestion control.)97 538.2 Q
(TCP-lik)5.5 E 2.75(eC)-.11 G
(ongestion Control is particularly useful for senders)-2.75 E(who w)97
551.2 Q(ould lik)-.11 E 2.75(et)-.11 G 2.75(ot)-2.75 G(ak)-2.75 E 2.75
(ea)-.11 G(dv)-2.75 E(antage of the a)-.275 E -.275(va)-.22 G
(ilable bandwidth in an en).275 E(vironment with)-.44 E
(rapidly changing conditions.)97 564.2 Q .396 -.198(TO B)97 590.2 T 2.75
(ED).198 G(ELETED BY THE RFC EDIT)-2.75 E(OR UPON PUBLICA)-.198 E(TION:)
-1.221 E(Changes from draft-ietf-dccp-ccid2-01.txt:)97 616.2 Q 2.75(*A)
97 642.2 S(dded "Security Considerations" and "IAN)-2.75 E 2.75(AC)-.385
G(onsiderations" sections.)-2.75 E 2.75(*R)97 668.2 S(efer e)-2.75 E
(xplicitly to SA)-.165 E(CK-based TCP)-.44 E 2.75(,a)-1.221 G
(nd \215esh out Section 3 \("Congestion Control)-2.75 E(on Data P)97
681.2 Q(ack)-.165 E(ets"\).)-.11 E 2.75(*W)97 707.2 S
(hen cwnd < ssthresh, increase cwnd by one per ne)-2.75 E(wly ackno)
-.275 E(wledged pack)-.275 E(et up to)-.11 E
(some limit, in line with TCP Appropriate Byte Counting.)97 720.2 Q(Flo)
72 769 Q(yd/K)-.11 E 333.671(ohler [P)-.385 F(age 1])-.165 E 0 Cg EP
%%Page: 2 2
%%BeginPageSetup
BP
%%EndPageSetup
/F0 11/Times-Roman@0 SF(INTERNET)72 49 Q 65.641(-DRAFT Expires:)-1.012 F
(No)2.75 E -.165(ve)-.165 G(mber 2003).165 E(May 2003)115.955 E 2.75(*R)
97 85 S(e\214ned de\214nition of quiescence.)-2.75 E
(Changes from draft-ietf-dccp-ccid2-00.txt:)97 111 Q 2.75(*S)97 137 S
(aid that the Ackno)-2.75 E(wledgement Number reports the lar)-.275 E
(gest sequence number)-.198 E 2.75(,n)-.44 G(ot)-2.75 E
(the most recent pack)97 150 Q(et, for consistenc)-.11 E 2.75(yw)-.165 G
(ith draft-ietf-dccp-spec.)-2.75 E 2.75(*A)97 176 S
(dded notes about ECN nonces for ackno)-2.75 E
(wledgements, and about dealing with)-.275 E(piggyback)97 189 Q
(ed ackno)-.11 E(wledgements.)-.275 E(Flo)72 769 Q(yd/K)-.11 E 333.671
(ohler [P)-.385 F(age 2])-.165 E 0 Cg EP
%%Page: 3 3
%%BeginPageSetup
BP
%%EndPageSetup
/F0 11/Times-Roman@0 SF(INTERNET)72 49 Q 65.641(-DRAFT Expires:)-1.012 F
(No)2.75 E -.165(ve)-.165 G(mber 2003).165 E(May 2003)115.955 E/F1 13
/Times-Bold@0 SF -1.196(Ta)239.126 85 S(ble of Contents)1.196 E/F2 10
/Times-Roman@0 SF(1. Introduction)97 123 Q F0 11(......................)
3.56 G F2(4)11.5 E(1.1. Usage Scenario)107 135 Q F0 11
(....................).52 G F2(4)11.5 E(1.2. Example Half-Connection)107
147 Q F0 11(................)12.74 G F2(4)11.5 E
(2. Connection Establishment)97 159 Q F0 11(..................)2.72 G F2
(5)11.5 E(3. Congestion Control on Data P)97 171 Q(ack)-.15 E(ets)-.1 E
F0 11(...............)3.95 G F2(5)11.5 E(4. Ackno)97 183 Q(wledgements)
-.25 E F0 11(....................)1.32 G F2(7)11.5 E
(4.1. Congestion Control on Ackno)107 195 Q(wledgements)-.25 E F0 11
(............).2 G F2(7)11.5 E(4.1.1. Deri)117 207 Q -.25(va)-.25 G
(tion of Ack Ratio Decrease).25 E F0 11(.............)6.18 G F2(8)11.5 E
(4.2. Quiescence)107 219 Q F0 11(.....................)3.16 G F2(8)11.5
E(4.3. Ackno)107 231 Q(wledgements of Ackno)-.25 E(wledgements)-.25 E F0
11(............)1.31 G F2(9)11.5 E
(5. Explicit Congestion Noti\214cation)97 243 Q F0 11(................)
5.49 G F2(9)11.5 E(6. Rele)97 255 Q -.25(va)-.25 G
(nt Options and Features).25 E F0 11(................)12.96 G F2(9)11.5
E(7. Application Requirements)97 267 Q F0 11(..................)2.73 G
F2(9)11.5 E(8. Thanks)97 279 Q F0 11(.......................)9.81 G F2
(9)11.5 E(9. Normati)97 291 Q .3 -.15(ve R)-.25 H(eferences).15 E F0 11
(...................)4.96 G F2(10)6.5 E(10. Informati)97 303 Q .3 -.15
(ve R)-.25 H(eferences).15 E F0 11(..................)9.27 G F2(10)6.5 E
(11. Security Considerations)97 315 Q F0 11(..................)7.17 G F2
(10)6.5 E(12. IAN)97 327 Q 2.5(AC)-.35 G(onsiderations)-2.5 E F0 11
(...................)2.11 G F2(10)6.5 E(13. Authors' Addresses)97 339 Q
F0 11(...................)10.1 G F2(10)6.5 E F0(Flo)72 769 Q(yd/K)-.11 E
333.671(ohler [P)-.385 F(age 3])-.165 E 0 Cg EP
%%Page: 4 4
%%BeginPageSetup
BP
%%EndPageSetup
/F0 11/Times-Roman@0 SF(INTERNET)72 49 Q 65.641(-DRAFT Expires:)-1.012 F
(No)2.75 E -.165(ve)-.165 G(mber 2003).165 E(May 2003)115.955 E/F1 11
/Times-Bold@0 SF(1.)72 85 Q/F2 14/Times-Bold@0 SF(Intr)5.5 E(oduction)
-.252 E F0(This document contains the pro\214le for Congestion Control \
Identi\214er 2, TCP-lik)100.8 101.6 Q(e)-.11 E(Congestion Control, in t\
he Datagram Congestion Control Protocol \(DCCP\).)100.8 114.6 Q
(DCCP uses)5.5 E(Congestion Control Identi\214ers, or CCIDs, to specify\
 the congestion control mechanism in)100.8 127.6 Q(use on a half-connec\
tion. \(A half-connection might consist of data pack)100.8 140.6 Q
(ets sent from DCCP)-.11 E 2.75(At)100.8 153.6 S 2.75(oD)-2.75 G
(CCP B, plus ackno)-2.75 E
(wledgements sent from DCCP B to DCCP A. DCCP A is the)-.275 E
(HC-Sender)100.8 166.6 Q 2.75(,a)-.44 G(nd DCCP B the HC-Recei)-2.75 E
-.165(ve)-.275 G .88 -.44(r, f).165 H
(or this half-connection. In this document, we).44 E(abbre)100.8 179.6 Q
(viate HC-Sender and HC-Recei)-.275 E -.165(ve)-.275 G 2.75(ra).165 G
2.75(s")-2.75 G(sender" and "recei)-2.75 E -.165(ve)-.275 G
(r", respecti).165 E -.165(ve)-.275 G(ly).165 E 2.75(.T)-.715 G(hese)
-2.75 E(terms are de\214ned more fully in [DCCP].\))100.8 192.6 Q
(The TCP-lik)100.8 209.2 Q 2.75(eC)-.11 G
(ongestion Control CCID sends data using a close v)-2.75 E
(ariant of TCP')-.275 E(s)-.605 E
(congestion control mechanisms, particularly SA)100.8 222.2 Q
(CK-based TCP')-.44 E 2.75(sc)-.605 G(ongestion control)-2.75 E(mechani\
sms [RFC 3517]. It is suitable for senders who can adapt to the abrupt \
changes in)100.8 235.2 Q(congestion windo)100.8 248.2 Q 2.75(wt)-.275 G
(ypical of AIMD \(Additi)-2.75 E .33 -.165(ve I)-.275 H
(ncrease Multiplicati).165 E .33 -.165(ve D)-.275 H(ecrease\)).165 E
(congestion control in TCP)100.8 261.2 Q 2.75(,a)-1.221 G
(nd particularly useful for senders who w)-2.75 E(ould lik)-.11 E 2.75
(et)-.11 G 2.75(ot)-2.75 G(ak)-2.75 E(e)-.11 E(adv)100.8 274.2 Q
(antage of the a)-.275 E -.275(va)-.22 G(ilable bandwidth in an en).275
E(vironment with rapidly changing conditions.)-.44 E
(The congestion control mechanisms described here closely follo)100.8
290.8 Q 2.75(wm)-.275 G(echanisms)-2.75 E
(standardized by the IETF for use in SA)100.8 303.8 Q(CK-based TCP)-.44
E 2.75(.W)-1.221 G 2.75(ed)-3.63 G 2.75(on)-2.75 G
(ot de\214ne these mechanisms)-2.75 E(ane)100.8 316.8 Q
(w; instead, we rely on e)-.275 E
(xisting TCP documentation, such as [RFC 793], [RFC 3465],)-.165 E
(and [RFC 3517]. This is both to a)100.8 329.8 Q -.22(vo)-.22 G
(id respecifying TCP).22 E 2.75(,a)-1.221 G(nd to allo)-2.75 E 2.75(wo)
-.275 G(ur speci\214cation to)-2.75 E(track TCP as it e)100.8 342.8 Q
-.22(vo)-.275 G(lv).22 E(es. Conformant CCID 2 implementations MA)-.165
E 2.75(Yt)-1.155 G(rack TCP')-2.75 E 2.75(se)-.605 G -.22(vo)-3.025 G
(lution).22 E(directly)100.8 355.8 Q 2.75(,a)-.715 G 2.75(su)-2.75 G
(pdates are standardized in the IETF)-2.75 E 2.75(,r)-.88 G
(ather than w)-2.75 E(aiting for re)-.11 E(visions of this)-.275 E(docu\
ment. CCID 2 does de\214ne an additional mechanism not currently standa\
rdized for use)100.8 368.8 Q(in TCP)100.8 381.8 Q 2.75(,n)-1.221 G
(amely congestion control on ackno)-2.75 E(wledgements as achie)-.275 E
-.165(ve)-.275 G 2.75(db).165 G 2.75(yt)-2.75 G(he Ack Ratio.)-2.75 E
(Also, DCCP is a datagram protocol, so se)100.8 394.8 Q -.165(ve)-.275 G
(ral parameters whose units are bytes in TCP).165 E(,)-1.221 E
(such as the congestion windo)100.8 407.8 Q 2.75(wc)-.275 G(wnd, ha)
-2.75 E .33 -.165(ve u)-.22 H(nits of pack).165 E(ets in DCCP)-.11 E 5.5
(.U)-1.221 G(nreliability also)-5.5 E(leads to dif)100.8 420.8 Q
(ferences from TCP: DCCP ne)-.275 E -.165(ve)-.275 G 2.75(rr).165 G
(etransmits a pack)-2.75 E(et, so congestion control)-.11 E
(mechanisms that distinguish retransmissions from ne)100.8 433.8 Q 2.75
(wp)-.275 G(ack)-2.75 E(ets need rethinking in the)-.11 E(DCCP conte)
100.8 446.8 Q(xt.)-.165 E -.165(Fo)100.8 463.4 S 2.75(rs).165 G
(implicity)-2.75 E 2.75(,w)-.715 G 2.75(er)-2.75 G
(efer to DCCP-Data pack)-2.75 E(ets sent by the sender)-.11 E 2.75(,a)
-.44 G(nd DCCP-Ack pack)-2.75 E(ets)-.11 E(sent by the recei)100.8 476.4
Q -.165(ve)-.275 G 1.21 -.605(r. B).165 H(oth of these cate).605 E
(gories are meant to include piggyback)-.165 E(ed DCCP-)-.11 E
(DataAck pack)100.8 489.4 Q(ets.)-.11 E(The k)100.8 506 Q .33 -.165
(ey w)-.11 H(ords "MUST", "MUST NO).055 E(T", "REQ)-.44 E
(UIRED", "SHALL", "SHALL NO)-.11 E(T",)-.44 E("SHOULD", "SHOULD NO)100.8
519 Q(T", "RECOMMENDED",)-.44 E("MA)5.5 E(Y", and "OPTION)-1.155 E
(AL" in this)-.385 E
(document are to be interpreted as described in [RFC 2119].)100.8 532 Q
F1(1.1.)72 558 Q/F3 13/Times-Bold@0 SF(Usage Scenario)5.5 E F0(TCP-lik)
100.8 574.6 Q 2.75(eC)-.11 G(ongestion Control is intended to pro)-2.75
E(vide congestion control for applications that)-.165 E(do not require \
fully reliable data transmission, or that desire to implement reliabili\
ty on top)100.8 587.6 Q(of DCCP)100.8 600.6 Q 5.5(.I)-1.221 G 2.75(ti)
-5.5 G 2.75(sa)-2.75 G(ppropriate for \215o)-2.75 E(ws that w)-.275 E
(ould lik)-.11 E 2.75(et)-.11 G 2.75(or)-2.75 G(ecei)-2.75 E .33 -.165
(ve a)-.275 H 2.75(sm).165 G(uch bandwidth as)-2.75 E(possible o)100.8
613.6 Q -.165(ve)-.165 G 2.75(rt).165 G(he long term, consistent with t\
he use of end-to-end congestion control, and)-2.75 E
(that are willing to under)100.8 626.6 Q
(go halving of the congestion windo)-.198 E 2.75(wi)-.275 G 2.75(nr)
-2.75 G(esponse to a congestion)-2.75 E -2.365 -.275(ev e)100.8 639.6 T
(nt.).275 E F1(1.2.)72 665.6 Q F3(Example Half-Connection)5.5 E F0
(This e)100.8 682.2 Q(xample sho)-.165 E
(ws the typical progress of a half-connection using TCP-lik)-.275 E 2.75
(eC)-.11 G(ongestion)-2.75 E(Control speci\214ed by CCID 2, not includi\
ng connection initiation and termination.)100.8 695.2 Q(Ag)5.5 E(ain,)
-.055 E(the "sender" is the HC-Sender)100.8 708.2 Q 2.75(,a)-.44 G
(nd the "recei)-2.75 E -.165(ve)-.275 G(r" is the HC-Recei).165 E -.165
(ve)-.275 G 3.96 -.605(r. \().165 H(The e).605 E(xample is)-.165 E
(informati)100.8 721.2 Q -.165(ve)-.275 G 2.75(,n).165 G(ot normati)
-2.75 E -.165(ve)-.275 G(.\)).165 E(Flo)72 769 Q(yd/K)-.11 E 275.921
(ohler Section)-.385 F 2.75(1.2. [P)2.75 F(age 4])-.165 E 0 Cg EP
%%Page: 5 5
%%BeginPageSetup
BP
%%EndPageSetup
/F0 11/Times-Roman@0 SF(INTERNET)72 49 Q 65.641(-DRAFT Expires:)-1.012 F
(No)2.75 E -.165(ve)-.165 G(mber 2003).165 E(May 2003)115.955 E 13.224
(\(1\) The)100.8 85 R(sender sends DCCP-Data pack)2.75 E
(ets, where the number of pack)-.11 E(ets sent is go)-.11 E -.165(ve)
-.165 G(rned).165 E(by a congestion windo)129.6 98 Q 1.43 -.715(w, c)
-.275 H(wnd, as in TCP).715 E 5.5(.E)-1.221 G(ach DCCP-Data pack)-5.5 E
(et uses a sequence)-.11 E(number)129.6 111 Q 5.5(.T)-.605 G
(he sender also sends an Ack Ratio feature option specifying the number)
-5.5 E(of data pack)129.6 124 Q(ets to be co)-.11 E -.165(ve)-.165 G
(red by an Ack pack).165 E(et from the recei)-.11 E -.165(ve)-.275 G
-.605(r.).165 G(Assuming that the half-connection is ECN capable \(the \
ECN Capable feature is)129.6 140.6 Q(turned on---the def)129.6 153.6 Q
(ault\), each DCCP-Data pack)-.11 E
(et is sent as ECN-Capable with either)-.11 E(the ECT\(0\) or the ECT\(\
1\) codepoint set, as described in [ECN NONCE].)129.6 166.6 Q 13.224
(\(2\) The)100.8 183.2 R(recei)2.75 E -.165(ve)-.275 G 2.75(rs).165 G
(ends a DCCP-Ack pack)-2.75 E(et ackno)-.11 E(wledging the data pack)
-.275 E(ets for e)-.11 E -.165(ve)-.275 G(ry).165 E(Ack Ratio data pack)
129.6 196.2 Q(ets transmitted by the sender)-.11 E 5.5(.E)-.605 G
(ach DCCP-Ack pack)-5.5 E(et uses a)-.11 E
(sequence number and contains an Ack V)129.6 209.2 Q(ector)-1.221 E 5.5
(.T)-.605 G(he sequence number ackno)-5.5 E(wledged)-.275 E
(in DCCP-Ack pack)129.6 222.2 Q(ets is that of the recei)-.11 E -.165
(ve)-.275 G 2.75(dp).165 G(ack)-2.75 E(et with the highest sequence)-.11
E(number)129.6 235.2 Q 2.75(,r)-.44 G(ather than a TCP-lik)-2.75 E 2.75
(ec)-.11 G(umulati)-2.75 E .33 -.165(ve a)-.275 H(ckno).165 E
(wledgement.)-.275 E(If the half-connection is ECN capable, the recei)
129.6 251.8 Q -.165(ve)-.275 G 2.75(rr).165 G(eturns the sum of recei)
-2.75 E -.165(ve)-.275 G 2.75(dE).165 G(CN)-2.75 E(Nonces via Ack V)
129.6 264.8 Q(ector options, allo)-1.221 E
(wing the sender to probabilistically v)-.275 E(erify that)-.165 E
(the recei)129.6 277.8 Q -.165(ve)-.275 G 2.75(ri).165 G 2.75(sn)-2.75 G
(ot misbeha)-2.75 E 2.75(ving. DCCP-Ack)-.22 F(pack)2.75 E
(ets from the recei)-.11 E -.165(ve)-.275 G 2.75(ra).165 G(re also sent)
-2.75 E(as ECN-Capable, b)129.6 290.8 Q(ut there is no need to v)-.22 E
(erify the nonces.)-.165 E 13.224(\(3\) The)100.8 307.4 R
(sender continues sending DCCP-Data pack)2.75 E
(ets as controlled by the congestion)-.11 E(windo)129.6 320.4 Q 4.18
-.715(w. U)-.275 H(pon recei).715 E(ving DCCP-Ack pack)-.275 E
(ets, the sender e)-.11 E(xamines their Ack V)-.165 E(ectors)-1.221 E
(to learn about mark)129.6 333.4 Q(ed or dropped data pack)-.11 E
(ets, and adjusts its congestion windo)-.11 E(w)-.275 E(accordingly)
129.6 346.4 Q 5.5(.B)-.715 G(ecause this is unreliable transfer)-5.5 E
2.75(,t)-.44 G(he sender does not retransmit)-2.75 E(dropped pack)129.6
359.4 Q(ets.)-.11 E 13.224(\(4\) Because)100.8 376 R(DCCP-Ack pack)2.75
E(ets use sequence numbers, the sender has direct)-.11 E
(information about the fraction of lost or mark)129.6 389 Q
(ed DCCP-Ack pack)-.11 E 2.75(ets. The)-.11 F(sender)2.75 E
(responds to lost or mark)129.6 402 Q(ed DCCP-Ack pack)-.11 E
(ets by modifying the Ack Ratio sent to)-.11 E(the recei)129.6 415 Q
-.165(ve)-.275 G -.605(r.).165 G 13.224(\(5\) The)100.8 431.6 R
(sender ackno)2.75 E(wledges the recei)-.275 E -.165(ve)-.275 G(r').165
E 2.75(sa)-.605 G(ckno)-2.75 E(wledgements at least once per)-.275 E
(congestion windo)129.6 444.6 Q 4.18 -.715(w. I)-.275 H 2.75(fb).715 G
(oth half-connections are acti)-2.75 E -.165(ve)-.275 G 2.75(,t).165 G
(he sender')-2.75 E(s)-.605 E(ackno)129.6 457.6 Q
(wledgement of the recei)-.275 E -.165(ve)-.275 G(r').165 E 2.75(sa)
-.605 G(ckno)-2.75 E(wledgements is included in the sender')-.275 E(s)
-.605 E(ackno)129.6 470.6 Q(wledgement of the recei)-.275 E -.165(ve)
-.275 G(r').165 E 2.75(sd)-.605 G(ata pack)-2.75 E 2.75(ets. If)-.11 F
(the re)2.75 E -.165(ve)-.275 G(rse-path half-connection).165 E
(is quiescent, the sender sends a DCCP-DataAck pack)129.6 483.6 Q
(et that includes an)-.11 E(Ackno)129.6 496.6 Q
(wledgement Number in the header)-.275 E(.)-.605 E 13.224(\(6\) The)
100.8 513.2 R(sender estimates round-trip times and calculates a T)2.75
E(imeOut \(T)-.385 E(O\) v)-.198 E(alue much as)-.275 E(the R)129.6
526.2 Q .396 -.198(TO \()-.66 H(Retransmit T).198 E
(imeout\) is calculated in TCP)-.385 E 5.5(.T)-1.221 G(he T)-5.5 E 2.75
(Oi)-.198 G 2.75(su)-2.75 G(sed to determine)-2.75 E(when a ne)129.6
539.2 Q 2.75(wD)-.275 G(CCP-Data pack)-2.75 E
(et can be transmitted when the sender has been limited)-.11 E
(by the congestion windo)129.6 552.2 Q 2.75(wa)-.275 G
(nd no feedback has been recei)-2.75 E -.165(ve)-.275 G 2.75(df).165 G
(rom the recei)-2.75 E -.165(ve)-.275 G -.605(r.).165 G/F1 11
/Times-Bold@0 SF(2.)72 578.2 Q/F2 14/Times-Bold@0 SF
(Connection Establishment)5.5 E F0(Use of the Ack V)100.8 594.8 Q
(ector is MAND)-1.221 E -.506 -1.221(AT O)-.44 H 1.43 -.715(RY o)1.221 H
2.75(nC).715 G(CID 2 half-connections, so the sender MUST)-2.75 E
(send a "Change\(Use Ack V)100.8 607.8 Q(ector)-1.221 E 2.75(,1)-.44 G
(\)" option to the recei)-2.75 E -.165(ve)-.275 G 2.75(ra).165 G 2.75
(sp)-2.75 G(art of connection)-2.75 E
(establishment. The sender SHOULD NO)100.8 620.8 Q 2.75(Ts)-.44 G
(end data until it has recei)-2.75 E -.165(ve)-.275 G 2.75(dt).165 G
(he corresponding)-2.75 E("Con\214rm\(Use Ack V)100.8 633.8 Q(ector)
-1.221 E 2.75(,1)-.44 G(\)" from the recei)-2.75 E -.165(ve)-.275 G
-.605(r.).165 G F1(3.)72 659.8 Q F2(Congestion Contr)5.5 E(ol on Data P)
-.252 E(ack)-.14 E(ets)-.14 E F0(CCID 2')100.8 676.4 Q 2.75(sc)-.605 G
(ongestion control mechanisms are based on those for SA)-2.75 E
(CK-based TCP [RFC)-.44 E(3517]. In particular)100.8 689.4 Q 2.75(,t)
-.44 G(he Ack V)-2.75 E(ector pro)-1.221 E
(vides strictly more information than that)-.165 E(transmitted in SA)
100.8 702.4 Q(CK options.)-.44 E(Flo)72 769 Q(yd/K)-.11 E 284.171
(ohler Section)-.385 F 2.75(3. [P)2.75 F(age 5])-.165 E 0 Cg EP
%%Page: 6 6
%%BeginPageSetup
BP
%%EndPageSetup
/F0 11/Times-Roman@0 SF(INTERNET)72 49 Q 65.641(-DRAFT Expires:)-1.012 F
(No)2.75 E -.165(ve)-.165 G(mber 2003).165 E(May 2003)115.955 E
(In particular)100.8 85 Q 2.75(,aC)-.44 G
(CID 2 data sender maintains three inte)-2.75 E
(ger parameters, whose units are in)-.165 E(pack)100.8 98 Q(ets:)-.11 E
13.224(\(1\) The)100.8 114.6 R(congestion windo)2.75 E 2.75(w")-.275 G
(cwnd", which equals the maximum number of data-)-2.75 E(carrying pack)
129.6 127.6 Q(ets allo)-.11 E(wed in the netw)-.275 E(ork at an)-.11 E
2.75(yt)-.165 G(ime. \("Data-carrying pack)-2.75 E(et" means)-.11 E(an)
129.6 140.6 Q 2.75(yD)-.165 G(CCP pack)-2.75 E
(et that contains user data: DCCP-Data, DCCP-DataAck, and)-.11 E
(occasionally DCCP-Request, DCCP-Response, and DCCP-Mo)129.6 153.6 Q
-.165(ve)-.165 G(.\)).165 E 13.224(\(2\) The)100.8 170.2 R(slo)2.75 E
(w-start threshold "ssthresh", which controls adjustments to cwnd.)-.275
E(When halv)129.6 186.8 Q(ed, cwnd and ssthresh ha)-.165 E .33 -.165
(ve t)-.22 H(heir v).165 E(alues rounded do)-.275 E(wn, e)-.275 E
(xcept that neither)-.165 E(parameter is e)129.6 199.8 Q -.165(ve)-.275
G 2.75(rl).165 G(ess than one.)-2.75 E 13.224(\(3\) The)100.8 216.4 R
(pipe v)2.75 E(alue "pipe", which is the sender')-.275 E 2.75(se)-.605 G
(stimate of the number of data-carrying)-2.75 E(pack)129.6 229.4 Q
(ets outstanding in the netw)-.11 E(ork.)-.11 E
(These parameters are manipulated, and their initial v)100.8 246 Q
(alues determined, according to SA)-.275 E(CK-)-.44 E(based TCP')100.8
259 Q 2.75(sb)-.605 G(eha)-2.75 E(vior)-.22 E 2.75(.T)-.605 G
(he rest of this section pro)-2.75 E(vides more speci\214c guidance.)
-.165 E(The sender MA)100.8 275.6 Q 2.75(Ys)-1.155 G
(end a data-carrying pack)-2.75 E
(et only when pipe < cwnd. In particular)-.11 E 2.75(,i)-.44 G(t)-2.75 E
(MUST NO)100.8 288.6 Q 2.75(Ts)-.44 G(end a data-carrying pack)-2.75 E
(et when pipe >= cwnd.)-.11 E(Ev)5.5 E(ery data-carrying pack)-.165 E
(et)-.11 E(sent increases pipe by 1.)100.8 301.6 Q
(The sender reduces pipe as it infers that data-carrying pack)100.8
318.2 Q(ets ha)-.11 E .33 -.165(ve l)-.22 H(eft the netw).165 E
(ork, either)-.11 E(by being recei)100.8 331.2 Q -.165(ve)-.275 G 2.75
(do).165 G 2.75(rb)-2.75 G 2.75(yb)-2.75 G(eing dropped. In particular:)
-2.75 E 13.224(\(1\) The)100.8 347.8 R
(sender reduces pipe by 1 for each pack)2.75 E(et ne)-.11 E(wly-ackno)
-.275 E(wledged as recei)-.275 E -.165(ve)-.275 G 2.75(d\().165 G(Ack)
-2.75 E -1.221(Ve)129.6 360.8 S
(ctor State 0 or State 1\) by some DCCP-Ack.)1.221 E 13.224(\(2\) The)
100.8 377.4 R(sender reduces pipe by 1 for each pack)2.75 E
(et it can infer as lost due to the DCCP)-.11 E(equi)129.6 390.4 Q -.275
(va)-.275 G(lent of "duplicate ackno).275 E
(wledgements". This depends on TCP')-.275 E(s)-.605 E(NUMDUP)129.6 403.4
Q -.44(AC)-1.012 G 2.75(Kp).44 G(arameter)-2.75 E 2.75(,t)-.44 G
(he number of duplicate ackno)-2.75 E(wledgements TCP needs)-.275 E
(to infer a loss, which currently equals 3. A pack)129.6 416.4 Q
(et P is inferred to be lost, rather than)-.11 E
(delayed, when at least NUMDUP)129.6 429.4 Q -.44(AC)-1.012 G 2.75(Kp)
.44 G(ack)-2.75 E(ets after P ha)-.11 E .33 -.165(ve b)-.22 H(een ackno)
.165 E(wledged as)-.275 E(recei)129.6 442.4 Q -.165(ve)-.275 G 2.75(d\()
.165 G(Ack V)-2.75 E(ector State 0 or 1\) by the recei)-1.221 E -.165
(ve)-.275 G -.605(r.).165 G 13.224(\(3\) Finally)100.8 459 R 2.75(,t)
-.715 G(he sender needs "retransmit" timeouts, handled lik)-2.75 E 2.75
(eT)-.11 G(CP')-2.75 E 2.75(sr)-.605 G(etransmission)-2.75 E
(timeouts, in case an entire windo)129.6 472 Q 2.75(wo)-.275 G 2.75(fp)
-2.75 G(ack)-2.75 E(ets are lost. The sender estimates the)-.11 E
(round-trip time at most once per windo)129.6 485 Q 2.75(wo)-.275 G 2.75
(fd)-2.75 G(ata, and uses the TCP algorithms for)-2.75 E
(maintaining the a)129.6 498 Q -.165(ve)-.22 G
(rage round-trip time, mean de).165 E(viation, and timeout v)-.275 E
(alue. Because)-.275 E
(DCCP does not retransmit data, DCCP does not require TCP')129.6 511 Q
2.75(sr)-.605 G(ecommended)-2.75 E(minimum timeout of one second. The e)
129.6 524 Q(xponential back)-.165 E(of)-.11 E 2.75(fo)-.275 G 2.75(ft)
-2.75 G(he timer is e)-2.75 E(xactly as)-.165 E(in TCP)129.6 537 Q(.)
-1.221 E(When a "retransmit" timeout occurs, the sender sets pipe to 0.)
129.6 553.6 Q(The sender MUST NO)100.8 570.2 Q 2.75(Td)-.44 G
(ecrement pipe more than once for an)-2.75 E 2.75(yg)-.165 G -2.365
-.275(iv e)-2.75 H 2.75(np).275 G(ack)-2.75 E 2.75(et. Duplicate)-.11 F
(ackno)100.8 583.2 Q(wledgements, for e)-.275 E(xample, MUST not af)
-.165 E(fect pipe. Furthermore, the sender MUST)-.275 E(NO)100.8 596.2 Q
2.75(Td)-.44 G(ecrement pipe for non-data pack)-2.75 E
(ets, such as DCCP-Acks, e)-.11 E -.165(ve)-.275 G 2.75(nt).165 G
(hough the Ack)-2.75 E -1.221(Ve)100.8 609.2 S
(ctor will contain information about them.)1.221 E(Congestion e)100.8
625.8 Q -.165(ve)-.275 G(nts, namely one or more pack).165 E
(ets lost or mark)-.11 E(ed from a windo)-.11 E 2.75(wo)-.275 G 2.75(fd)
-2.75 G(ata,)-2.75 E(cause CCID 2 to reduce its congestion windo)100.8
638.8 Q 1.43 -.715(w. F)-.275 H(or each congestion e).55 E -.165(ve)
-.275 G(nt, either indicated).165 E -.165(ex)100.8 651.8 S
(plicitly as an Ack V).165 E(ector State 1 \(ECN-mark)-1.221 E
(ed\) ackno)-.11 E(wledgement or inferred via)-.275 E("duplicate ackno)
100.8 664.8 Q(wledgements", cwnd is halv)-.275 E
(ed, then ssthresh is set to the ne)-.165 E 2.75(wc)-.275 G(wnd.)-2.75 E
(Cwnd is ne)100.8 677.8 Q -.165(ve)-.275 G 2.75(rr).165 G(educed belo)
-2.75 E 2.75(wo)-.275 G(ne pack)-2.75 E 2.75(et. After)-.11 F 2.75(at)
2.75 G(imeout, the slo)-2.75 E(w-start threshold is set to)-.275 E
(cwnd/2, then cwnd is set to one pack)100.8 690.8 Q(et.)-.11 E
(When cwnd < ssthresh, meaning that the sender is in slo)100.8 707.4 Q
(w-start, the congestion windo)-.275 E 2.75(wi)-.275 G(s)-2.75 E
(increased by one pack)100.8 720.4 Q(et for e)-.11 E -.165(ve)-.275 G
(ry ne).165 E(wly ackno)-.275 E(wledged \(with Ack V)-.275 E
(ector State 0 or 1\) data-)-1.221 E(Flo)72 769 Q(yd/K)-.11 E 284.171
(ohler Section)-.385 F 2.75(3. [P)2.75 F(age 6])-.165 E 0 Cg EP
%%Page: 7 7
%%BeginPageSetup
BP
%%EndPageSetup
/F0 11/Times-Roman@0 SF(INTERNET)72 49 Q 65.641(-DRAFT Expires:)-1.012 F
(No)2.75 E -.165(ve)-.165 G(mber 2003).165 E(May 2003)115.955 E
(carrying pack)100.8 85 Q(et, up to a maximum of Ack Ratio pack)-.11 E
(ets per ackno)-.11 E 2.75(wledgement. This)-.275 F(dif)100.8 98 Q
(fers from TCP')-.275 E 2.75(sh)-.605 G(istorical beha)-2.75 E(vior)-.22
E 2.75(,w)-.44 G(hich \(in DCCP terms\) w)-2.75 E(ould increase cwnd by)
-.11 E(one per DCCP-Ack recei)100.8 111 Q -.165(ve)-.275 G
(d, not by one per pack).165 E(et ne)-.11 E(wly ackno)-.275 E
(wledged by some DCCP-)-.275 E(Ack; b)100.8 124 Q
(ut it is in line with TCP')-.22 E 2.75(sb)-.605 G(eha)-2.75 E
(vior with appropriate byte counting [RFC 3465].)-.22 E
(When cwnd >= ssthresh, the congestion windo)100.8 137 Q 2.75(wi)-.275 G
2.75(si)-2.75 G(ncreased by one pack)-2.75 E(et for e)-.11 E -.165(ve)
-.275 G(ry).165 E(windo)100.8 150 Q 2.75(wo)-.275 G 2.75(fd)-2.75 G
(ata ackno)-2.75 E(wledged without lost or mark)-.275 E(ed pack)-.11 E
(ets.)-.11 E/F1 11/Times-Bold@0 SF(4.)72 176 Q/F2 14/Times-Bold@0 SF
(Ackno)5.5 E(wledgements)-.14 E F0(This section describes ho)100.8 192.6
Q 2.75(wt)-.275 G(he recei)-2.75 E -.165(ve)-.275 G 2.75(rr).165 G
(eports ackno)-2.75 E(wledgement information back to the)-.275 E(sender)
100.8 205.6 Q 5.5(.D)-.605 G(CCP-Ack pack)-5.5 E(ets from the recei)-.11
E -.165(ve)-.275 G 2.75(rM).165 G(UST include Ack V)-2.75 E
(ector options, as well)-1.221 E(as an Ackno)100.8 218.6 Q
(wledgement Number ackno)-.275 E(wledging the pack)-.275 E
(et with the lar)-.11 E(gest v)-.198 E(alid sequence)-.275 E
(number recei)100.8 231.6 Q -.165(ve)-.275 G 2.75(df).165 G
(rom the sender)-2.75 E 5.5(.A)-.605 G(ckno)-5.5 E
(wledgement data in the Ack V)-.275 E(ector options)-1.221 E
(SHOULD generally co)100.8 244.6 Q -.165(ve)-.165 G 2.75(rt).165 G
(he recei)-2.75 E -.165(ve)-.275 G(r').165 E 2.75(se)-.605 G
(ntire Unackno)-2.75 E(wledged W)-.275 E(indo)-.44 E 1.43 -.715(w, a)
-.275 H 2.75(sd).715 G(escribed in)-2.75 E([DCCP].)100.8 257.6 Q
(The sender speci\214es the Ack Ratio to be used by the recei)100.8
274.2 Q -.165(ve)-.275 G 3.96 -.605(r. I).165 H 2.75(nt).605 G
(he absence of congestion)-2.75 E(on the re)100.8 287.2 Q -.165(ve)-.275
G(rse path, the Ack Ratio is set to tw).165 E 2.75(oi)-.11 G 2.75(ft)
-2.75 G(he congestion windo)-2.75 E 2.75(wi)-.275 G 2.75(st)-2.75 G
(hree or more)-2.75 E(pack)100.8 300.2 Q
(ets, and is set to one otherwise.)-.11 E(The recei)5.5 E -.165(ve)-.275
G 2.75(rs).165 G(ends a DCCP-Ack pack)-2.75 E(et for e)-.11 E -.165(ve)
-.275 G(ry Ack).165 E(Ratio pack)100.8 313.2 Q(ets sent by the sender)
-.11 E(.)-.605 E F1(4.1.)72 339.2 Q/F3 13/Times-Bold@0 SF
(Congestion Contr)5.5 E(ol on Ackno)-.234 E(wledgements)-.13 E F0
(In CCID 2, the ackno)100.8 355.8 Q(wledgement sub\215o)-.275 E 2.75(wi)
-.275 G 2.75(sl)-2.75 G(oosely congestion-controlled by the Ack)-2.75 E
(Ratio speci\214ed by the sender)100.8 368.8 Q 5.5(.T)-.605 G(he recei)
-5.5 E -.165(ve)-.275 G 2.75(rs).165 G(ends \(cwnd / Ack Ratio\) ackno)
-2.75 E(wledgement)-.275 E(pack)100.8 381.8 Q
(ets for each congestion windo)-.11 E 2.75(wo)-.275 G 2.75(fd)-2.75 G
(ata pack)-2.75 E 2.75(ets. W)-.11 F 2.75(en)-.88 G(ote that CCID 2 dif)
-2.75 E(fers from)-.275 E(TCP)100.8 394.8 Q 2.75(,w)-1.221 G
(hich presently has no congestion control for pure ackno)-2.75 E
(wledgement traf)-.275 E 2.75(\214c. F)-.275 F(or)-.165 E(congestion co\
ntrol for the pure ack stream, DCCP does not try to be TCP-friendly)
100.8 407.8 Q 2.75(,b)-.715 G(ut just)-2.97 E(tries to a)100.8 420.8 Q
-.22(vo)-.22 G(id congestion collapse, and to be some).22 E
(what better than TCP in e)-.275 E(xplicitly)-.165 E
(reducing the ack sending rate in the presence of a high pack)100.8
433.8 Q(et loss or marking rate on the)-.11 E(return path.)100.8 446.8 Q
(If DCCP B, the HC-Recei)100.8 463.4 Q -.165(ve)-.275 G .88 -.44(r, i)
.165 H 2.75(sa).44 G(cti)-2.75 E -.165(ve)-.275 G
(ly sending data---it is not quiescent---then required).165 E(ackno)
100.8 476.4 Q(wledgements may be piggyback)-.275 E(ed on DCCP B')-.11 E
2.75(sd)-.605 G(ata pack)-2.75 E(ets. In this situation,)-.11 E
(DCCP B MA)100.8 489.4 Q 2.75(Ys)-1.155 G(end more piggyback)-2.75 E
(ed ackno)-.11 E(wledgements than the Ack Ratio w)-.275 E(ould)-.11 E
(allo)100.8 502.4 Q(w; b)-.275 E(ut it MUST send at least as man)-.22 E
2.75(ya)-.165 G(ckno)-2.75 E(wledgements as the Ack Ratio requires.)
-.275 E(Concei)100.8 515.4 Q -.275(va)-.275 G(bly).275 E 2.75(,t)-.715 G
(he CCID in use for the B-to-A half-connection might limit DCCP B')-2.75
E(s)-.605 E(sending rate to less than the ackno)100.8 528.4 Q
(wledgement rate required for the A-to-B half-)-.275 E 2.75
(connection. DCCP)100.8 541.4 R 2.75(BM)2.75 G(UST follo)-2.75 E 2.75
(wb)-.275 G(oth constraints. In practice, this means that DCCP B)-2.75 E
(will not piggyback data on e)100.8 554.4 Q -.165(ve)-.275 G(ry ackno)
.165 E(wledgement.)-.275 E
(There are three constraints on the Ack Ratio.)100.8 571 Q
(First, it is al)5.5 E -.11(wa)-.11 G(ys an inte).11 E(ger)-.165 E 5.5
(.S)-.605 G(econd, it is)-5.5 E(ne)100.8 584 Q -.165(ve)-.275 G 2.75(rg)
.165 G(reater than half the congestion windo)-2.75 E 2.75(w\()-.275 G
(with fractions rounded up\).)-2.75 E(Third, it is at)5.5 E(least tw)
100.8 597 Q 2.75(of)-.11 G(or a congestion windo)-2.75 E 2.75(wo)-.275 G
2.75(ff)-2.75 G(our or more pack)-2.75 E(ets.)-.11 E(DCCP-Ack pack)100.8
613.6 Q(ets from the recei)-.11 E -.165(ve)-.275 G 2.75(rc).165 G
(ontain sequence numbers, so the sender can infer)-2.75 E
(when DCCP-Ack pack)100.8 626.6 Q(ets are lost.)-.11 E
(The sender considers a DCCP-Ack pack)5.5 E(et lost if at least)-.11 E
(NUMDUP)100.8 639.6 Q -.44(AC)-1.012 G 2.75(Kp).44 G(ack)-2.75 E
(ets with higher sequence numbers ha)-.11 E .33 -.165(ve b)-.22 H
(een recei).165 E -.165(ve)-.275 G 2.75(df).165 G(rom the)-2.75 E(recei)
100.8 652.6 Q -.165(ve)-.275 G 1.21 -.605(r. \().165 H(Ag).605 E
(ain, NUMDUP)-.055 E -.44(AC)-1.012 G 2.75(Ke).44 G(quals 3.\))-2.75 E
(If DCCP-Ack pack)5.5 E(ets from the recei)-.11 E -.165(ve)-.275 G 2.75
(ra).165 G(re)-2.75 E(mark)100.8 665.6 Q(ed in the netw)-.11 E
(ork, the sender sees these marks directly)-.11 E(.)-.715 E
(DCCP responds to congestion e)100.8 682.2 Q -.165(ve)-.275 G
(nts on the return path by modifying the Ack Ratio,).165 E
(loosely emulating TCP)100.8 695.2 Q 5.5(.F)-1.221 G
(or each congestion windo)-5.665 E 2.75(wo)-.275 G 2.75(fd)-2.75 G
(ata with lost or mark)-2.75 E(ed DCCP-)-.11 E(Ack pack)100.8 708.2 Q
(ets, the Ack Ratio is doubled, subject to the constraints noted abo)
-.11 E -.165(ve)-.165 G 5.5(.S).165 G(imilarly)-5.5 E 2.75(,i)-.715 G(f)
-2.75 E(the Ack Ratio is R, then for each \(cwnd/\(R^2 - R\)\) congesti\
on windo)100.8 721.2 Q(ws of data with no lost)-.275 E(Flo)72 769 Q
(yd/K)-.11 E 275.921(ohler Section)-.385 F 2.75(4.1. [P)2.75 F(age 7])
-.165 E 0 Cg EP
%%Page: 8 8
%%BeginPageSetup
BP
%%EndPageSetup
/F0 11/Times-Roman@0 SF(INTERNET)72 49 Q 65.641(-DRAFT Expires:)-1.012 F
(No)2.75 E -.165(ve)-.165 G(mber 2003).165 E(May 2003)115.955 E(or mark)
100.8 85 Q(ed DCCP-Ack pack)-.11 E
(ets, the Ack Ratio is decreased by 1, ag)-.11 E(ain subject to the)
-.055 E(constraints on the Ack Ratio. See the section belo)100.8 98 Q
2.75(wf)-.275 G(or the deri)-2.75 E -.275(va)-.275 G 2.75(tion. F).275 F
(or a constant)-.165 E(congestion windo)100.8 111 Q 1.43 -.715(w, t)
-.275 H(his gi).715 E -.165(ve)-.275 G 2.75(sa).165 G 2.75(nA)-2.75 G
(ck sending rate that is roughly TCP-friendly)-2.75 E 5.5(.W)-.715 G
2.75(en)-6.38 G(ote)-2.75 E
(that, because the sending rate for the ackno)100.8 124 Q
(wledgement pack)-.275 E(ets changes as a function of)-.11 E
(both the Ack Ratio and the congestion windo)100.8 137 Q 1.43 -.715
(w, t)-.275 H(he dynamics will be rather comple).715 E(x, and)-.165 E
(this Ack congestion control mechanism is intended only to be v)100.8
150 Q(ery roughly TCP-friendly)-.165 E(.)-.715 E
(As a result of the constraints gi)100.8 166.6 Q -.165(ve)-.275 G 2.75
(ne).165 G(arlier in this section, the recei)-2.75 E -.165(ve)-.275 G
2.75(ra).165 G -.11(lwa)-2.75 G(ys sends at least).11 E(one ack pack)
100.8 179.6 Q(et for a congestion windo)-.11 E 2.75(wo)-.275 G 2.75(fo)
-2.75 G(ne pack)-2.75 E(et, and the recei)-.11 E -.165(ve)-.275 G 2.75
(ra).165 G -.11(lwa)-2.75 G(ys sends at).11 E(least tw)100.8 192.6 Q
2.75(oa)-.11 G(ck pack)-2.75 E(ets per windo)-.11 E 2.75(wo)-.275 G 2.75
(fd)-2.75 G(ata otherwise.)-2.75 E(Thus, the recei)5.5 E -.165(ve)-.275
G 2.75(rc).165 G(ould be sending)-2.75 E(tw)100.8 205.6 Q 2.75(oa)-.11 G
(ck pack)-2.75 E(ets per windo)-.11 E 2.75(wo)-.275 G 2.75(fd)-2.75 G
(ata e)-2.75 E -.165(ve)-.275 G 2.75(ni).165 G 2.75(nt)-2.75 G(he f)
-2.75 E(ace of v)-.11 E(ery hea)-.165 E(vy congestion on the)-.22 E(re)
100.8 218.6 Q -.165(ve)-.275 G(rse path.).165 E 1.76 -.88(We w)5.5 H
(ould note, ho).77 E(we)-.275 E -.165(ve)-.275 G .88 -.44(r, t).165 H
(hat if congestion is suf).44 E(\214ciently hea)-.275 E(vy that all of)
-.22 E(the ack pack)100.8 231.6 Q(ets are dropped, then the sender f)
-.11 E(alls back on a timeout, and the e)-.11 E(xponential)-.165 E(back)
100.8 244.6 Q(of)-.11 E 2.75(fo)-.275 G 2.75(ft)-2.75 G(he timer)-2.75 E
2.75(,a)-.44 G 2.75(si)-2.75 G 2.75(nT)-2.75 G(CP)-2.75 E 5.5(.T)-1.221
G(hus, if congestion is suf)-5.5 E(\214ciently hea)-.275 E(vy on the re)
-.22 E -.165(ve)-.275 G(rse).165 E
(path, then the sender reduces its sending rate on the forw)100.8 257.6
Q(ard path, which reduces the rate)-.11 E(on the re)100.8 270.6 Q -.165
(ve)-.275 G(rse path as well.).165 E/F1 11/Times-Bold@0 SF 2.75
(4.1.1. Deri)72 296.6 R -.11(va)-.11 G(tion of Ack Ratio Decr).11 E
(ease)-.198 E F0(The congestion a)100.8 313.2 Q -.22(vo)-.22 G
(idance phase of TCP increases cwnd by one MSS for e).22 E -.165(ve)
-.275 G(ry congestion-).165 E(free windo)100.8 326.2 Q 6.93 -.715(w. A)
-.275 H(pplying this congestion a).715 E -.22(vo)-.22 G(idance beha).22
E(vior to the ack traf)-.22 E(\214c, this w)-.275 E(ould)-.11 E
(correspond to increasing the number of DCCP-Ack pack)100.8 339.2 Q
(ets per windo)-.11 E 2.75(wb)-.275 G 2.75(yo)-2.75 G(ne after e)-2.75 E
-.165(ve)-.275 G(ry).165 E(congestion-free windo)100.8 352.2 Q 2.75(wo)
-.275 G 2.75(fD)-2.75 G(CCP-Ack pack)-2.75 E(ets. W)-.11 E 2.75(ec)-.88
G(annot achie)-2.75 E .33 -.165(ve t)-.275 H(his e).165 E
(xactly using the)-.165 E(Ack Ratio, since the Ack Ratio is an inte)
100.8 365.2 Q(ger)-.165 E 5.5(.I)-.605 G
(nstead, we must decrease the Ack Ratio by)-5.5 E(one after K windo)
100.8 378.2 Q(ws ha)-.275 E .33 -.165(ve b)-.22 H
(een sent without a congestion e).165 E -.165(ve)-.275 G(nt on the re)
.165 E -.165(ve)-.275 G(rse path, where).165 E 2.75(Ki)100.8 391.2 S
2.75(sc)-2.75 G(hosen so that the long-term number of DCCP-Ack pack)
-2.75 E(ets per congestion windo)-.11 E 2.75(wi)-.275 G(s)-2.75 E
(roughly TCP-friendly)100.8 404.2 Q 2.75(,f)-.715 G(ollo)-2.75 E
(wing AIMD congestion control.)-.275 E(In CCID 2, K = \(cwnd/\(R^2 - R\
\)\), where R is the current Ack Ratio. This result w)100.8 420.8 Q(as)
-.11 E(calculated as follo)100.8 433.8 Q(ws:)-.275 E/F2 11/Courier@0 SF
6.6(R=A)180 452.8 S(ck Ratio = # data packets / ack packets, and)-6.6 E
6.6(W=C)180 465.8 S(ongestion Window = # data packets / window, so)-6.6
E(W/R = # ack packets / window.)166.8 478.8 Q
(Requirement: Increase W/R by 1 per congestion-free window.)127.2 504.8
Q(But can only reduce R by increments of one.)127.2 517.8 Q
(Therefore, find K so that, after K congestion-free windows,)127.2 543.8
Q(the adjusted W/R would equal W/\(R-1\).)127.2 556.8 Q
(\(W/R\) + K = W/\(R-1\), so)127.2 582.8 Q 6.6(K=W)180 595.8 S
(/\(R-1\) - W/R = W/\(R^2 - R\).)-6.6 E F1(4.2.)72 627.8 Q/F3 13
/Times-Bold@0 SF(Quiescence)5.5 E F0(This section refers to quiescence \
in the DCCP sense \(see section 8.1 of [DCCP]\): Ho)100.8 644.4 Q(w)
-.275 E(does a CCID 2 recei)100.8 657.4 Q -.165(ve)-.275 G 2.75(rd).165
G(etermine that the corresponding sender is not sending an)-2.75 E 2.75
(yd)-.165 G(ata?)-2.75 E(Let T equal the greater of 0.2 seconds and tw)
100.8 674 Q 2.75(or)-.11 G(ound-trip times.)-2.75 E(Then the recei)5.5 E
-.165(ve)-.275 G 2.75(rd).165 G(etects)-2.75 E
(that the sender has gone quiescent when at least T seconds ha)100.8 687
Q .33 -.165(ve p)-.22 H(assed without recei).165 E(ving)-.275 E(an)100.8
700 Q 2.75(ya)-.165 G(dditional data from the sender)-2.75 E 2.75(,a)
-.44 G(nd the sender has ackno)-2.75 E(wledged recei)-.275 E -.165(ve)
-.275 G 2.75(rA).165 G(ck V)-2.75 E(ectors)-1.221 E(that co)100.8 713 Q
-.165(ve)-.165 G(red all data pack).165 E(ets sent.)-.11 E
(That is, once the sender ackno)5.5 E(wledges the recei)-.275 E -.165
(ve)-.275 G(r').165 E(s)-.605 E(Flo)72 769 Q(yd/K)-.11 E 275.921
(ohler Section)-.385 F 2.75(4.2. [P)2.75 F(age 8])-.165 E 0 Cg EP
%%Page: 9 9
%%BeginPageSetup
BP
%%EndPageSetup
/F0 11/Times-Roman@0 SF(INTERNET)72 49 Q 65.641(-DRAFT Expires:)-1.012 F
(No)2.75 E -.165(ve)-.165 G(mber 2003).165 E(May 2003)115.955 E(Ack V)
100.8 85 Q
(ectors and the sender has not sent additional data for at least T)
-1.221 E 2.75(,t)-.814 G(he recei)-2.75 E -.165(ve)-.275 G 2.75(rc).165
G(an)-2.75 E(determine that the sender is quiescent.)100.8 98 Q/F1 11
/Times-Bold@0 SF(4.3.)72 124 Q/F2 13/Times-Bold@0 SF(Ackno)5.5 E
(wledgements of Ackno)-.13 E(wledgements)-.13 E F0(The sender)100.8
140.6 Q 2.75(,D)-.44 G(CCP A, must occasionally ackno)-2.75 E
(wledge the recei)-.275 E -.165(ve)-.275 G(r').165 E 2.75(sa)-.605 G
(ckno)-2.75 E(wledgements, so)-.275 E(that the recei)100.8 153.6 Q -.165
(ve)-.275 G 2.75(rc).165 G(an free up Ack V)-2.75 E(ector state.)-1.221
E(The sender can also send ackno)5.5 E(wledgements)-.275 E(to mak)100.8
166.6 Q 2.75(ec)-.11 G(hanges to the Ack Ratio. W)-2.75 E 2.75(ea)-.88 G
(ssume that DCCP A simply sends Change\(Ack)-2.75 E
(Ratio\) options whene)100.8 179.6 Q -.165(ve)-.275 G 2.75(rr).165 G
(equired. T)-2.75 E 2.75(ol)-.88 G(et the recei)-2.75 E -.165(ve)-.275 G
2.75(rf).165 G(ree Ack V)-2.75 E(ector state, DCCP A must)-1.221 E
(occasionally ackno)100.8 192.6 Q(wledge that it has recei)-.275 E -.165
(ve)-.275 G 2.75(do).165 G(ne of DCCP B')-2.75 E 2.75(sa)-.605 G(ckno)
-2.75 E(wledgements. When)-.275 E(both half-connections are acti)100.8
205.6 Q -.165(ve)-.275 G 2.75(,t).165 G
(his information is automatically contained in A)-2.75 E -.605('s)-1.221
G(ackno)100.8 218.6 Q(wledgements to B')-.275 E 2.75(sd)-.605 G
(ata. If the B-to-A half-connection goes quiescent, ho)-2.75 E(we)-.275
E -.165(ve)-.275 G -.44(r,).165 G(DCCP A must do it proacti)100.8 231.6
Q -.165(ve)-.275 G(ly).165 E(.)-.715 E(In particular)100.8 248.2 Q 2.75
(,a)-.44 G 2.75(na)-2.75 G(cti)-2.75 E .33 -.165(ve s)-.275 H
(ender MUST occasionally ackno).165 E(wledge the recei)-.275 E -.165(ve)
-.275 G(r').165 E(s)-.605 E(ackno)100.8 261.2 Q(wledgements, probably b\
y encapsulating a datagram in a DCCP-DataAck pack)-.275 E(et. No)-.11 E
(ackno)100.8 274.2 Q(wledgement options are necessary)-.275 E 2.75(,j)
-.715 G(ust the rele)-2.75 E -.275(va)-.275 G(nt Ackno).275 E
(wledgement Number in the)-.275 E(DCCP-DataAck header)100.8 287.2 Q 2.75
(.T)-.605 G(he sender SHOULD ackno)-2.75 E
(wledge approximately one of the)-.275 E(recei)100.8 300.2 Q -.165(ve)
-.275 G(r').165 E 2.75(sa)-.605 G(ckno)-2.75 E
(wledgements per congestion windo)-.275 E 1.43 -.715(w. O)-.275 H 2.75
(fc).715 G(ourse, the sender')-2.75 E 2.75(sa)-.605 G(pplication)-2.75 E
(might f)100.8 313.2 Q(all silent.)-.11 E
(This is no problem; when neither side is sending data, a sender can w)
5.5 E(ait)-.11 E(arbitrarily long before sending an ack.)100.8 326.2 Q
F1(5.)72 352.2 Q/F3 14/Times-Bold@0 SF
(Explicit Congestion Noti\214cation)5.5 E F0
(ECN may be used with CCID 2.)100.8 368.8 Q
(If ECN is used, then the ECN Nonce will automatically)5.5 E
(be used for the data pack)100.8 381.8 Q(ets, follo)-.11 E
(wing the speci\214cation for the ECN Nonce in TCP in)-.275 E
([ECN NONCE]. F)100.8 394.8 Q(or the data sub\215o)-.165 E 1.43 -.715
(w, t)-.275 H(he sender sets either the ECT\(0\) or ECT\(1\)).715 E
(codepoint on DCCP-Data pack)100.8 407.8 Q 2.75(ets. Information)-.11 F
(about mark)2.75 E(ed pack)-.11 E(ets is returned in the)-.11 E(Ack V)
100.8 420.8 Q(ector)-1.221 E 5.5(.B)-.605 G
(ecause the information in the Ack V)-5.5 E
(ector is reliably transferred, DCCP does)-1.221 E
(not need the TCP \215ags of ECN-Echo and Congestion W)100.8 433.8 Q
(indo)-.44 E 2.75(wR)-.275 G(educed.)-2.75 E -.165(Fo)100.8 450.4 S 2.75
(ru).165 G(nmark)-2.75 E(ed data pack)-.11 E(ets, the recei)-.11 E -.165
(ve)-.275 G 2.75(rc).165 G(omputes the ECN Nonce Echo as in [ECN)-2.75 E
(NONCE], and returns the ECN Nonce Echo in DCCP-Ack pack)100.8 463.4 Q
2.75(ets. The)-.11 F(sender uses the)2.75 E(ECN Nonce to protect ag)
100.8 476.4 Q(ainst the accidental or malicious concealment of mark)
-.055 E(ed pack)-.11 E(ets.)-.11 E(Because the ack sub\215o)100.8 493 Q
2.75(wi)-.275 G 2.75(sc)-2.75 G
(ongestion-controlled, ECN can also be used for DCCP-Ack)-2.75 E(pack)
100.8 506 Q 2.75(ets. In)-.11 F(this case we do not mak)2.75 E 2.75(eu)
-.11 G(se of the ECN Nonce, because it w)-2.75 E(ould not be easy)-.11 E
(to pro)100.8 519 Q(vide protection ag)-.165 E
(ainst the concealment of mark)-.055 E(ed ack pack)-.11 E
(ets by the sender)-.11 E 2.75(,a)-.44 G(nd)-2.75 E
(because the sender does not ha)100.8 532 Q .33 -.165(ve a)-.22 H 2.75
(sm).165 G(uch moti)-2.75 E -.275(va)-.275 G
(tion for lying about the mark rate on).275 E(ackno)100.8 545 Q
(wledgements.)-.275 E F1(6.)72 571 Q F3(Rele)5.5 E -.14(va)-.21 G
(nt Options and F).14 E(eatur)-.35 E(es)-.252 E F0(DCCP')100.8 587.6 Q
2.75(sA)-.605 G(ck V)-2.75 E(ector option and its Ack Ratio, Use Ack V)
-1.221 E(ector)-1.221 E 2.75(,a)-.44 G(nd ECN Capable features)-2.75 E
(are rele)100.8 600.6 Q -.275(va)-.275 G(nt for CCID 2.).275 E F1(7.)72
626.6 Q F3 -.35(Ap)5.5 G(plication Requir).35 E(ements)-.252 E F0
(There are no speci\214c application requirements for TCP-lik)100.8
643.2 Q 2.75(eC)-.11 G(ongestion Control.)-2.75 E F1(8.)72 669.2 Q F3
(Thanks)5.5 E F0 1.76 -.88(We t)100.8 685.8 T(hank Mark Handle).88 E
2.75(ya)-.165 G(nd Jitendra P)-2.75 E(adh)-.165 E
(ye for their help in de\214ning CCID 2.)-.055 E(Flo)72 769 Q(yd/K)-.11
E 284.171(ohler Section)-.385 F 2.75(8. [P)2.75 F(age 9])-.165 E 0 Cg EP
%%Page: 10 10
%%BeginPageSetup
BP
%%EndPageSetup
/F0 11/Times-Roman@0 SF(INTERNET)72 49 Q 65.641(-DRAFT Expires:)-1.012 F
(No)2.75 E -.165(ve)-.165 G(mber 2003).165 E(May 2003)115.955 E/F1 11
/Times-Bold@0 SF(9.)72 85 Q/F2 14/Times-Bold@0 SF(Normati)5.5 E .28 -.14
(ve R)-.14 H(efer).14 E(ences)-.252 E F0([DCCP] E. K)100.8 101.6 Q
(ohler)-.385 E 2.75(,M)-.44 G 2.75(.H)-2.75 G(andle)-2.75 E 1.43 -.715
(y, S)-.165 H 2.75(.F).715 G(lo)-2.75 E(yd, and J. P)-.11 E(adh)-.165 E
2.75(ye. Datagram)-.055 F(Congestion Control)2.75 E
(Protocol, draft-ietf-dccp-spec-01.txt, w)129.6 114.6 Q
(ork in progress, March 2003.)-.11 E([ECN NONCE] Neil Spring, Da)100.8
131.2 Q(vid W)-.22 E(etherall, and Da)-.88 E(vid Ely)-.22 E 5.5(.R)-.715
G(ob)-5.5 E(ust ECN Signaling with)-.22 E
(Nonces, draft-ietf-tsvwg-tcp-nonce-04.txt, w)129.6 144.2 Q
(ork in progress, October 2002.)-.11 E([RFC 793] J. Postel, editor)100.8
160.8 Q 2.75(.T)-.605 G(ransmission Control Protocol. RFC 793.)-3.135 E
([RFC 2026] S. Bradner)100.8 177.4 Q 2.75(.T)-.605 G
(he Internet Standards Process -- Re)-2.75 E(vision 3. RFC 2026.)-.275 E
([RFC 2119] S. Bradner)100.8 194 Q 2.75(.K)-.605 G .33 -.165(ey W)-3.025
H(ords F)-.715 E(or Use in RFCs to Indicate Requirement Le)-.165 E -.165
(ve)-.275 G(ls. RFC).165 E(2119.)129.6 207 Q([RFC 2581] M. Allman, V)
100.8 223.6 Q 2.75(.P)-1.419 G(axson, and W)-2.915 E 2.75(.S)-1.012 G
(te)-2.75 E -.165(ve)-.275 G 2.75(ns. TCP).165 F
(Congestion Control. RFC 2581.)2.75 E([RFC 3465] M. Allman. TCP Congest\
ion Control with Appropriate Byte Counting \(ABC\).)100.8 240.2 Q
(RFC 3465.)129.6 253.2 Q([RFC 3517] E. Blanton, M. Allman, K. F)100.8
269.8 Q(all, and L. W)-.165 E(ang. A Conserv)-.88 E(ati)-.275 E .33
-.165(ve S)-.275 H(electi).165 E -.165(ve)-.275 G(Ackno)129.6 282.8 Q
(wledgment \(SA)-.275 E(CK\)-based Loss Reco)-.44 E -.165(ve)-.165 G
(ry Algorithm for TCP).165 E 2.75(.R)-1.221 G(FC 3517.)-2.75 E F1(10.)72
308.8 Q F2(Inf)5.5 E(ormati)-.35 E .28 -.14(ve R)-.14 H(efer).14 E
(ences)-.252 E F1(11.)72 334.8 Q F2(Security Considerations)5.5 E F0
(Security considerations for DCCP ha)100.8 351.4 Q .33 -.165(ve b)-.22 H
(een discussed in [DCCP], and security).165 E(considerations for TCP ha)
100.8 364.4 Q .33 -.165(ve b)-.22 H(een discussed in [RFC 2581].).165 E
([RFC 2581] discusses w)100.8 381 Q(ays that an attack)-.11 E
(er could impair the performance of a TCP)-.11 E
(connection by dropping pack)100.8 394 Q(ets, or by for)-.11 E(ging e)
-.198 E(xtra duplicate ackno)-.165 E(wledgements or)-.275 E(ackno)100.8
407 Q(wledgements for ne)-.275 E 2.75(wd)-.275 G 2.75(ata. W)-2.75 F
2.75(ea)-.88 G(re not a)-2.75 E -.11(wa)-.165 G(re of an).11 E 2.75(yn)
-.165 G .55 -.275(ew s)-2.75 H(ecurity considerations).275 E
(created by this document in its use of TCP-lik)100.8 420 Q 2.75(ec)-.11
G(ongestion control.)-2.75 E F1(12.)72 446 Q F2(IAN)5.5 E 3.5(AC)-.28 G
(onsiderations)-3.5 E F0(There are no ne)100.8 462.6 Q 2.75(wI)-.275 G
(AN)-2.75 E 2.75(Ac)-.385 G(onsiderations created in this document.)
-2.75 E F1(13.)72 488.6 Q F2 -.7(Au)5.5 G(thors' Addr).7 E(esses)-.252 E
F0(Sally Flo)100.8 507.6 Q(yd <\215o)-.11 E(yd@icir)-.11 E(.or)-.605 E
(g>)-.198 E(Eddie K)100.8 520.6 Q(ohler <k)-.385 E(ohler@icir)-.11 E
(.or)-.605 E(g>)-.198 E(ICSI Center for Internet Research,)100.8 546.6 Q
(1947 Center Street, Suite 600)100.8 559.6 Q(Berk)100.8 572.6 Q(ele)-.11
E 1.43 -.715(y, C)-.165 H 2.75(A9).715 G(4704.)-2.75 E(Flo)72 769 Q
(yd/K)-.11 E 273.171(ohler Section)-.385 F 2.75(13. [P)2.75 F(age 10])
-.165 E 0 Cg EP
%%Trailer
end
%%EOF