-
Notifications
You must be signed in to change notification settings - Fork 202
/
draft-ietf-quic-transport.html
4468 lines (4325 loc) · 424 KB
/
draft-ietf-quic-transport.html
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html lang="en" xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
<head profile="http://www.w3.org/2006/03/hcard http://dublincore.org/documents/2008/08/04/dc-html/">
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii" />
<title>QUIC: A UDP-Based Multiplexed and Secure Transport</title>
<style type="text/css">/*<![CDATA[*/
body {
font: 16px "Helvetica Neue","Open Sans",Helvetica,Calibri,sans-serif;
color: #333;
font-size-adjust: 0.5;
line-height: 24px;
margin: 75px auto;
max-width: 624px;
padding: 0 5px;
}
.title, .filename, h1, h2, h3, h4, h5 {
font: 16px "Roboto Condensed","Helvetica Neue","Open Sans",Helvetica,Calibri,sans-serif;
font-size-adjust: 0.5;
font-weight: bold;
color: #333;
line-height: 100%;
margin: 1.2em 0 0.3em;
}
.title, #rfc\.title h1 { font-size: 32px; }
h1, section h1, h2, section h2, section h3, nav h2 { font-size: 20px; }
h3, section h4, h4, section h5 { font-size: 16px; }
h1 a[href], h2 a[href], h3 a[href], h4 a[href] {
color: #333;
}
table {
margin-left: 0em;
border-collapse: collapse;
}
th {
text-align: left;
border-bottom: 2px solid #ddd;
}
td {
border-top: 1px solid #ddd;
vertical-align: top;
}
tr:nth-child(2n+1) > td,
tr:nth-child(2n+1) > th {
background-color: #f9f9f9;
}
td.reference {
max-width: 200px;
border-top: none;
padding-right: 1em;
}
.right {
text-align: right;
}
table.header, table#rfc\.headerblock {
width: 100%;
}
table.header td, table#rfc\.headerblock td {
border: none;
background-color: transparent;
color: black;
padding: 0;
}
.filename {
display: block;
color: rgb(119, 119, 119);
font-size: 20px;
font-weight: normal;
line-height: 100%;
margin: 10px 0 32px;
}
#rfc\.abstract+p, #rfc\.abstract+p code, #rfc\.abstract+p samp, #rfc\.abstract+p tt {
font-size: 20px;
line-height: 28px;
}
samp, tt, code, pre, span.tt {
font-size: 13.5px;
font-family: Consolas, monospace;
font-size-adjust: none;
}
pre {
background-color: #eee;
border: 1px solid #ddd;
overflow-x: auto;
padding: 5px;
margin: 5px;
}
.figure, caption {
font-style: italic;
margin: 0 1.5em;
text-align: left;
}
address {
margin: 16px 2px;
line-height: 20px;
}
.vcard {
font-style: normal;
}
.vcardline {
display: block;
}
.vcardline .fn, address b {
font-weight: normal;
}
.vcardline .hidden {
display: none;
}
dl {
margin-left: 1em;
}
dl.dl-horizontal: {
margin-left: 0;
}
dl > dt {
float: left;
margin-right: 1em;
}
dl.nohang > dt {
float: none;
}
dl > dd {
margin-bottom: .5em;
}
dl.compact > dd {
margin-bottom: 0em;
}
dl > dd > dl {
margin-top: 0.5em;
margin-bottom: 0em;
}
ul.empty {
list-style-type: none;
}
ul.empty li {
margin-top: .5em;
}
hr {
border: 0;
border-top: 1px solid #eee;
}
hr.noprint {
display: none;
}
a {
text-decoration: none;
}
a[href] {
color: #2a6496;
}
a[href]:hover {
background-color: #eee;
}
p, ol, ul, li {
padding: 0;
}
p {
margin: 0.5em 0;
}
ol, ul {
margin: 0.2em 0 0.2em 2em;
}
li {
margin: 0.2em 0;
}
address {
font-style: normal;
}
ul.toc ul {
margin: 0 0 0 2em;
}
ul.toc li {
list-style: none;
margin: 0;
}
@media screen and (min-width: 924px) {
body {
padding-right: 350px;
}
body>ul.toc, body>#rfc\.toc {
position: fixed;
bottom: 0;
right: 0;
right: calc(50vw - 500px);
width: 300px;
z-index: 1;
overflow: auto;
overscroll-behavior: contain;
}
body>#rfc\.toc {
top: 55px;
}
body>ul.toc {
top: 100px;
}
ul.toc {
margin: 0 0 0 4px;
font-size: 12px;
line-height: 20px;
}
ul.toc ul {
margin-left: 1.2em;
}
}
.github-fork-ribbon-wrapper {
display: none;
}
@media screen and (min-width: 800px) {
/* "Fork me on GitHub" CSS ribbon based on
* https://github.com/simonwhitaker/github-fork-ribbon-css
*/
.github-fork-ribbon {
position: absolute;
padding: 2px 0;
background-color: #a00;
background-image: linear-gradient(to bottom, rgba(0, 0, 0, 0), rgba(0, 0, 0, 0.15));
box-shadow: 0 2px 3px 0 rgba(0, 0, 0, 0.5);
font: 700 12px "Helvetica Neue", Helvetica, Arial, sans-serif;
pointer-events: auto;
top: 38px;
right: -45px;
transform: rotate(45deg);
}
.github-fork-ribbon a[href],
.github-fork-ribbon a[href]:hover {
color: #fff;
background-color: transparent;
text-decoration: none;
text-shadow: 0 -1px rgba(0, 0, 0, 0.5);
text-align: center;
width: 190px;
line-height: 18px;
display: inline-block;
padding: 2px 0;
border: 1.5px dotted #fff;
border-color: rgba(255, 255, 255, 0.6);
}
.github-fork-ribbon-wrapper {
display: block;
width: 130px;
height: 130px;
position: absolute;
overflow: hidden;
top: 0; right: 0;
z-index: 2;
pointer-events: none;
}
}
@media screen and (min-width: 1000px) {
.github-fork-ribbon-wrapper {
position: fixed;
}
/*]]>*/</style>
<meta name="viewport" content="initial-scale=1.0">
<link href="#rfc.toc" rel="Contents">
<link href="#rfc.section.1" rel="Chapter" title="1 Introduction">
<link href="#rfc.section.1.1" rel="Chapter" title="1.1 Document Structure">
<link href="#rfc.section.1.2" rel="Chapter" title="1.2 Terms and Definitions">
<link href="#rfc.section.1.3" rel="Chapter" title="1.3 Notational Conventions">
<link href="#rfc.section.2" rel="Chapter" title="2 Streams">
<link href="#rfc.section.2.1" rel="Chapter" title="2.1 Stream Types and Identifiers">
<link href="#rfc.section.2.2" rel="Chapter" title="2.2 Sending and Receiving Data">
<link href="#rfc.section.2.3" rel="Chapter" title="2.3 Stream Prioritization">
<link href="#rfc.section.2.4" rel="Chapter" title="2.4 Required Operations on Streams">
<link href="#rfc.section.3" rel="Chapter" title="3 Stream States">
<link href="#rfc.section.3.1" rel="Chapter" title="3.1 Sending Stream States">
<link href="#rfc.section.3.2" rel="Chapter" title="3.2 Receiving Stream States">
<link href="#rfc.section.3.3" rel="Chapter" title="3.3 Permitted Frame Types">
<link href="#rfc.section.3.4" rel="Chapter" title="3.4 Bidirectional Stream States">
<link href="#rfc.section.3.5" rel="Chapter" title="3.5 Solicited State Transitions">
<link href="#rfc.section.4" rel="Chapter" title="4 Flow Control">
<link href="#rfc.section.4.1" rel="Chapter" title="4.1 Data Flow Control">
<link href="#rfc.section.4.2" rel="Chapter" title="4.2 Flow Credit Increments">
<link href="#rfc.section.4.3" rel="Chapter" title="4.3 Handling Stream Cancellation">
<link href="#rfc.section.4.4" rel="Chapter" title="4.4 Stream Final Size">
<link href="#rfc.section.4.5" rel="Chapter" title="4.5 Controlling Concurrency">
<link href="#rfc.section.5" rel="Chapter" title="5 Connections">
<link href="#rfc.section.5.1" rel="Chapter" title="5.1 Connection ID">
<link href="#rfc.section.5.1.1" rel="Chapter" title="5.1.1 Issuing Connection IDs">
<link href="#rfc.section.5.1.2" rel="Chapter" title="5.1.2 Consuming and Retiring Connection IDs">
<link href="#rfc.section.5.2" rel="Chapter" title="5.2 Matching Packets to Connections">
<link href="#rfc.section.5.2.1" rel="Chapter" title="5.2.1 Client Packet Handling">
<link href="#rfc.section.5.2.2" rel="Chapter" title="5.2.2 Server Packet Handling">
<link href="#rfc.section.5.3" rel="Chapter" title="5.3 Life of a QUIC Connection">
<link href="#rfc.section.5.4" rel="Chapter" title="5.4 Required Operations on Connections">
<link href="#rfc.section.6" rel="Chapter" title="6 Version Negotiation">
<link href="#rfc.section.6.1" rel="Chapter" title="6.1 Sending Version Negotiation Packets">
<link href="#rfc.section.6.2" rel="Chapter" title="6.2 Handling Version Negotiation Packets">
<link href="#rfc.section.6.2.1" rel="Chapter" title="6.2.1 Version Negotiation Between Draft Versions">
<link href="#rfc.section.6.3" rel="Chapter" title="6.3 Using Reserved Versions">
<link href="#rfc.section.7" rel="Chapter" title="7 Cryptographic and Transport Handshake">
<link href="#rfc.section.7.1" rel="Chapter" title="7.1 Example Handshake Flows">
<link href="#rfc.section.7.2" rel="Chapter" title="7.2 Negotiating Connection IDs">
<link href="#rfc.section.7.3" rel="Chapter" title="7.3 Transport Parameters">
<link href="#rfc.section.7.3.1" rel="Chapter" title="7.3.1 Values of Transport Parameters for 0-RTT">
<link href="#rfc.section.7.3.2" rel="Chapter" title="7.3.2 New Transport Parameters">
<link href="#rfc.section.7.4" rel="Chapter" title="7.4 Cryptographic Message Buffering">
<link href="#rfc.section.8" rel="Chapter" title="8 Address Validation">
<link href="#rfc.section.8.1" rel="Chapter" title="8.1 Address Validation During Connection Establishment">
<link href="#rfc.section.8.1.1" rel="Chapter" title="8.1.1 Address Validation using Retry Packets">
<link href="#rfc.section.8.1.2" rel="Chapter" title="8.1.2 Address Validation for Future Connections">
<link href="#rfc.section.8.1.3" rel="Chapter" title="8.1.3 Address Validation Token Integrity">
<link href="#rfc.section.8.2" rel="Chapter" title="8.2 Path Validation">
<link href="#rfc.section.8.3" rel="Chapter" title="8.3 Initiating Path Validation">
<link href="#rfc.section.8.4" rel="Chapter" title="8.4 Path Validation Responses">
<link href="#rfc.section.8.5" rel="Chapter" title="8.5 Successful Path Validation">
<link href="#rfc.section.8.6" rel="Chapter" title="8.6 Failed Path Validation">
<link href="#rfc.section.9" rel="Chapter" title="9 Connection Migration">
<link href="#rfc.section.9.1" rel="Chapter" title="9.1 Probing a New Path">
<link href="#rfc.section.9.2" rel="Chapter" title="9.2 Initiating Connection Migration">
<link href="#rfc.section.9.3" rel="Chapter" title="9.3 Responding to Connection Migration">
<link href="#rfc.section.9.3.1" rel="Chapter" title="9.3.1 Peer Address Spoofing">
<link href="#rfc.section.9.3.2" rel="Chapter" title="9.3.2 On-Path Address Spoofing">
<link href="#rfc.section.9.3.3" rel="Chapter" title="9.3.3 Off-Path Packet Forwarding">
<link href="#rfc.section.9.4" rel="Chapter" title="9.4 Loss Detection and Congestion Control">
<link href="#rfc.section.9.5" rel="Chapter" title="9.5 Privacy Implications of Connection Migration">
<link href="#rfc.section.9.6" rel="Chapter" title="9.6 Server’s Preferred Address">
<link href="#rfc.section.9.6.1" rel="Chapter" title="9.6.1 Communicating a Preferred Address">
<link href="#rfc.section.9.6.2" rel="Chapter" title="9.6.2 Responding to Connection Migration">
<link href="#rfc.section.9.6.3" rel="Chapter" title="9.6.3 Interaction of Client Migration and Preferred Address">
<link href="#rfc.section.9.7" rel="Chapter" title="9.7 Use of IPv6 Flow-Label and Migration">
<link href="#rfc.section.10" rel="Chapter" title="10 Connection Termination">
<link href="#rfc.section.10.1" rel="Chapter" title="10.1 Closing and Draining Connection States">
<link href="#rfc.section.10.2" rel="Chapter" title="10.2 Idle Timeout">
<link href="#rfc.section.10.3" rel="Chapter" title="10.3 Immediate Close">
<link href="#rfc.section.10.4" rel="Chapter" title="10.4 Stateless Reset">
<link href="#rfc.section.10.4.1" rel="Chapter" title="10.4.1 Detecting a Stateless Reset">
<link href="#rfc.section.10.4.2" rel="Chapter" title="10.4.2 Calculating a Stateless Reset Token">
<link href="#rfc.section.10.4.3" rel="Chapter" title="10.4.3 Looping">
<link href="#rfc.section.11" rel="Chapter" title="11 Error Handling">
<link href="#rfc.section.11.1" rel="Chapter" title="11.1 Connection Errors">
<link href="#rfc.section.11.2" rel="Chapter" title="11.2 Stream Errors">
<link href="#rfc.section.12" rel="Chapter" title="12 Packets and Frames">
<link href="#rfc.section.12.1" rel="Chapter" title="12.1 Protected Packets">
<link href="#rfc.section.12.2" rel="Chapter" title="12.2 Coalescing Packets">
<link href="#rfc.section.12.3" rel="Chapter" title="12.3 Packet Numbers">
<link href="#rfc.section.12.4" rel="Chapter" title="12.4 Frames and Frame Types">
<link href="#rfc.section.13" rel="Chapter" title="13 Packetization and Reliability">
<link href="#rfc.section.13.1" rel="Chapter" title="13.1 Packet Processing">
<link href="#rfc.section.13.2" rel="Chapter" title="13.2 Generating Acknowledgements">
<link href="#rfc.section.13.2.1" rel="Chapter" title="13.2.1 Sending ACK Frames">
<link href="#rfc.section.13.2.2" rel="Chapter" title="13.2.2 Managing ACK Ranges">
<link href="#rfc.section.13.2.3" rel="Chapter" title="13.2.3 Receiver Tracking of ACK Frames">
<link href="#rfc.section.13.2.4" rel="Chapter" title="13.2.4 Limiting ACK Ranges">
<link href="#rfc.section.13.2.5" rel="Chapter" title="13.2.5 Measuring and Reporting Host Delay">
<link href="#rfc.section.13.2.6" rel="Chapter" title="13.2.6 ACK Frames and Packet Protection">
<link href="#rfc.section.13.3" rel="Chapter" title="13.3 Retransmission of Information">
<link href="#rfc.section.13.4" rel="Chapter" title="13.4 Explicit Congestion Notification">
<link href="#rfc.section.13.4.1" rel="Chapter" title="13.4.1 ECN Counts">
<link href="#rfc.section.13.4.2" rel="Chapter" title="13.4.2 ECN Validation">
<link href="#rfc.section.14" rel="Chapter" title="14 Packet Size">
<link href="#rfc.section.14.1" rel="Chapter" title="14.1 Path Maximum Transmission Unit (PMTU)">
<link href="#rfc.section.14.2" rel="Chapter" title="14.2 ICMP Packet Too Big Messages">
<link href="#rfc.section.14.3" rel="Chapter" title="14.3 Datagram Packetization Layer PMTU Discovery">
<link href="#rfc.section.14.3.1" rel="Chapter" title="14.3.1 PMTU Probes Containing Source Connection ID">
<link href="#rfc.section.15" rel="Chapter" title="15 Versions">
<link href="#rfc.section.16" rel="Chapter" title="16 Variable-Length Integer Encoding">
<link href="#rfc.section.17" rel="Chapter" title="17 Packet Formats">
<link href="#rfc.section.17.1" rel="Chapter" title="17.1 Packet Number Encoding and Decoding">
<link href="#rfc.section.17.2" rel="Chapter" title="17.2 Long Header Packets">
<link href="#rfc.section.17.2.1" rel="Chapter" title="17.2.1 Version Negotiation Packet">
<link href="#rfc.section.17.2.2" rel="Chapter" title="17.2.2 Initial Packet">
<link href="#rfc.section.17.2.3" rel="Chapter" title="17.2.3 0-RTT">
<link href="#rfc.section.17.2.4" rel="Chapter" title="17.2.4 Handshake Packet">
<link href="#rfc.section.17.2.5" rel="Chapter" title="17.2.5 Retry Packet">
<link href="#rfc.section.17.3" rel="Chapter" title="17.3 Short Header Packets">
<link href="#rfc.section.17.3.1" rel="Chapter" title="17.3.1 Latency Spin Bit">
<link href="#rfc.section.18" rel="Chapter" title="18 Transport Parameter Encoding">
<link href="#rfc.section.18.1" rel="Chapter" title="18.1 Reserved Transport Parameters">
<link href="#rfc.section.18.2" rel="Chapter" title="18.2 Transport Parameter Definitions">
<link href="#rfc.section.19" rel="Chapter" title="19 Frame Types and Formats">
<link href="#rfc.section.19.1" rel="Chapter" title="19.1 PADDING Frame">
<link href="#rfc.section.19.2" rel="Chapter" title="19.2 PING Frame">
<link href="#rfc.section.19.3" rel="Chapter" title="19.3 ACK Frames">
<link href="#rfc.section.19.3.1" rel="Chapter" title="19.3.1 ACK Ranges">
<link href="#rfc.section.19.3.2" rel="Chapter" title="19.3.2 ECN Counts">
<link href="#rfc.section.19.4" rel="Chapter" title="19.4 RESET_STREAM Frame">
<link href="#rfc.section.19.5" rel="Chapter" title="19.5 STOP_SENDING Frame">
<link href="#rfc.section.19.6" rel="Chapter" title="19.6 CRYPTO Frame">
<link href="#rfc.section.19.7" rel="Chapter" title="19.7 NEW_TOKEN Frame">
<link href="#rfc.section.19.8" rel="Chapter" title="19.8 STREAM Frames">
<link href="#rfc.section.19.9" rel="Chapter" title="19.9 MAX_DATA Frame">
<link href="#rfc.section.19.10" rel="Chapter" title="19.10 MAX_STREAM_DATA Frame">
<link href="#rfc.section.19.11" rel="Chapter" title="19.11 MAX_STREAMS Frames">
<link href="#rfc.section.19.12" rel="Chapter" title="19.12 DATA_BLOCKED Frame">
<link href="#rfc.section.19.13" rel="Chapter" title="19.13 STREAM_DATA_BLOCKED Frame">
<link href="#rfc.section.19.14" rel="Chapter" title="19.14 STREAMS_BLOCKED Frames">
<link href="#rfc.section.19.15" rel="Chapter" title="19.15 NEW_CONNECTION_ID Frame">
<link href="#rfc.section.19.16" rel="Chapter" title="19.16 RETIRE_CONNECTION_ID Frame">
<link href="#rfc.section.19.17" rel="Chapter" title="19.17 PATH_CHALLENGE Frame">
<link href="#rfc.section.19.18" rel="Chapter" title="19.18 PATH_RESPONSE Frame">
<link href="#rfc.section.19.19" rel="Chapter" title="19.19 CONNECTION_CLOSE Frames">
<link href="#rfc.section.19.20" rel="Chapter" title="19.20 Extension Frames">
<link href="#rfc.section.20" rel="Chapter" title="20 Transport Error Codes">
<link href="#rfc.section.20.1" rel="Chapter" title="20.1 Application Protocol Error Codes">
<link href="#rfc.section.21" rel="Chapter" title="21 Security Considerations">
<link href="#rfc.section.21.1" rel="Chapter" title="21.1 Handshake Denial of Service">
<link href="#rfc.section.21.2" rel="Chapter" title="21.2 Amplification Attack">
<link href="#rfc.section.21.3" rel="Chapter" title="21.3 Optimistic ACK Attack">
<link href="#rfc.section.21.4" rel="Chapter" title="21.4 Slowloris Attacks">
<link href="#rfc.section.21.5" rel="Chapter" title="21.5 Stream Fragmentation and Reassembly Attacks">
<link href="#rfc.section.21.6" rel="Chapter" title="21.6 Stream Commitment Attack">
<link href="#rfc.section.21.7" rel="Chapter" title="21.7 Peer Denial of Service">
<link href="#rfc.section.21.8" rel="Chapter" title="21.8 Explicit Congestion Notification Attacks">
<link href="#rfc.section.21.9" rel="Chapter" title="21.9 Stateless Reset Oracle">
<link href="#rfc.section.21.10" rel="Chapter" title="21.10 Version Downgrade">
<link href="#rfc.section.21.11" rel="Chapter" title="21.11 Targeted Attacks by Routing">
<link href="#rfc.section.22" rel="Chapter" title="22 IANA Considerations">
<link href="#rfc.section.22.1" rel="Chapter" title="22.1 QUIC Transport Parameter Registry">
<link href="#rfc.section.22.2" rel="Chapter" title="22.2 QUIC Frame Type Registry">
<link href="#rfc.section.22.3" rel="Chapter" title="22.3 QUIC Transport Error Codes Registry">
<link href="#rfc.references" rel="Chapter" title="23 References">
<link href="#rfc.references.1" rel="Chapter" title="23.1 Normative References">
<link href="#rfc.references.2" rel="Chapter" title="23.2 Informative References">
<link href="#rfc.appendix.A" rel="Chapter" title="A Sample Packet Number Decoding Algorithm">
<link href="#rfc.appendix.B" rel="Chapter" title="B Change Log">
<link href="#rfc.appendix.B.1" rel="Chapter" title="B.1 Since draft-ietf-quic-transport-22">
<link href="#rfc.appendix.B.2" rel="Chapter" title="B.2 Since draft-ietf-quic-transport-21">
<link href="#rfc.appendix.B.3" rel="Chapter" title="B.3 Since draft-ietf-quic-transport-20">
<link href="#rfc.appendix.B.4" rel="Chapter" title="B.4 Since draft-ietf-quic-transport-19">
<link href="#rfc.appendix.B.5" rel="Chapter" title="B.5 Since draft-ietf-quic-transport-18">
<link href="#rfc.appendix.B.6" rel="Chapter" title="B.6 Since draft-ietf-quic-transport-17">
<link href="#rfc.appendix.B.7" rel="Chapter" title="B.7 Since draft-ietf-quic-transport-16">
<link href="#rfc.appendix.B.8" rel="Chapter" title="B.8 Since draft-ietf-quic-transport-15">
<link href="#rfc.appendix.B.9" rel="Chapter" title="B.9 Since draft-ietf-quic-transport-14">
<link href="#rfc.appendix.B.10" rel="Chapter" title="B.10 Since draft-ietf-quic-transport-13">
<link href="#rfc.appendix.B.11" rel="Chapter" title="B.11 Since draft-ietf-quic-transport-12">
<link href="#rfc.appendix.B.12" rel="Chapter" title="B.12 Since draft-ietf-quic-transport-11">
<link href="#rfc.appendix.B.13" rel="Chapter" title="B.13 Since draft-ietf-quic-transport-10">
<link href="#rfc.appendix.B.14" rel="Chapter" title="B.14 Since draft-ietf-quic-transport-09">
<link href="#rfc.appendix.B.15" rel="Chapter" title="B.15 Since draft-ietf-quic-transport-08">
<link href="#rfc.appendix.B.16" rel="Chapter" title="B.16 Since draft-ietf-quic-transport-07">
<link href="#rfc.appendix.B.17" rel="Chapter" title="B.17 Since draft-ietf-quic-transport-06">
<link href="#rfc.appendix.B.18" rel="Chapter" title="B.18 Since draft-ietf-quic-transport-05">
<link href="#rfc.appendix.B.19" rel="Chapter" title="B.19 Since draft-ietf-quic-transport-04">
<link href="#rfc.appendix.B.20" rel="Chapter" title="B.20 Since draft-ietf-quic-transport-03">
<link href="#rfc.appendix.B.21" rel="Chapter" title="B.21 Since draft-ietf-quic-transport-02">
<link href="#rfc.appendix.B.22" rel="Chapter" title="B.22 Since draft-ietf-quic-transport-01">
<link href="#rfc.appendix.B.23" rel="Chapter" title="B.23 Since draft-ietf-quic-transport-00">
<link href="#rfc.appendix.B.24" rel="Chapter" title="B.24 Since draft-hamilton-quic-transport-protocol-01">
<link href="#rfc.acknowledgments" rel="Chapter">
<link href="#rfc.contributors" rel="Chapter">
<link href="#rfc.authors" rel="Chapter">
<meta name="generator" content="xml2rfc version 2.22.2 - https://tools.ietf.org/tools/xml2rfc" />
<link rel="schema.dct" href="http://purl.org/dc/terms/" />
<meta name="dct.creator" content="Iyengar, J., Ed. and M. Thomson, Ed." />
<meta name="dct.identifier" content="urn:ietf:id:draft-ietf-quic-transport-latest" />
<meta name="dct.issued" scheme="ISO8601" content="2019-09-19" />
<meta name="dct.abstract" content="This document defines the core of the QUIC transport protocol. Accompanying documents describe QUIC’s loss detection and congestion control and the use of TLS for key negotiation." />
<meta name="description" content="This document defines the core of the QUIC transport protocol. Accompanying documents describe QUIC’s loss detection and congestion control and the use of TLS for key negotiation." />
</head>
<body>
<table class="header">
<tbody>
<tr>
<td class="left">QUIC</td>
<td class="right">J. Iyengar, Ed.</td>
</tr>
<tr>
<td class="left">Internet-Draft</td>
<td class="right">Fastly</td>
</tr>
<tr>
<td class="left">Intended status: Standards Track</td>
<td class="right">M. Thomson, Ed.</td>
</tr>
<tr>
<td class="left">Expires: March 22, 2020</td>
<td class="right">Mozilla</td>
</tr>
<tr>
<td class="left"></td>
<td class="right">September 19, 2019</td>
</tr>
</tbody>
</table>
<p class="title">QUIC: A UDP-Based Multiplexed and Secure Transport<br />
<span class="filename">draft-ietf-quic-transport-latest</span></p>
<h1 id="rfc.abstract"><a href="#rfc.abstract">Abstract</a></h1>
<p>This document defines the core of the QUIC transport protocol. Accompanying documents describe QUIC’s loss detection and congestion control and the use of TLS for key negotiation.</p>
<h1><a>Note to Readers</a></h1>
<p>Discussion of this draft takes place on the QUIC working group mailing list (quic@ietf.org), which is archived at <https://mailarchive.ietf.org/arch/search/?email_list=quic>.</p>
<p>Working Group information can be found at <https://github.com/quicwg>; source code and issues list for this draft can be found at <https://github.com/quicwg/base-drafts/labels/-transport>.</p>
<h1 id="rfc.status"><a href="#rfc.status">Status of This Memo</a></h1>
<p>This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79.</p>
<p>Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet-Drafts is at https://datatracker.ietf.org/drafts/current/.</p>
<p>Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress."</p>
<p>This Internet-Draft will expire on March 22, 2020.</p>
<h1 id="rfc.copyrightnotice"><a href="#rfc.copyrightnotice">Copyright Notice</a></h1>
<p>Copyright (c) 2019 IETF Trust and the persons identified as the document authors. All rights reserved.</p>
<p>This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.</p>
<hr class="noprint" />
<h1 class="np" id="rfc.toc"><a href="#rfc.toc">Table of Contents</a></h1>
<ul class="toc">
<li>1. <a href="#rfc.section.1">Introduction</a>
</li>
<ul><li>1.1. <a href="#rfc.section.1.1">Document Structure</a>
</li>
<li>1.2. <a href="#rfc.section.1.2">Terms and Definitions</a>
</li>
<li>1.3. <a href="#rfc.section.1.3">Notational Conventions</a>
</li>
</ul><li>2. <a href="#rfc.section.2">Streams</a>
</li>
<ul><li>2.1. <a href="#rfc.section.2.1">Stream Types and Identifiers</a>
</li>
<li>2.2. <a href="#rfc.section.2.2">Sending and Receiving Data</a>
</li>
<li>2.3. <a href="#rfc.section.2.3">Stream Prioritization</a>
</li>
<li>2.4. <a href="#rfc.section.2.4">Required Operations on Streams</a>
</li>
</ul><li>3. <a href="#rfc.section.3">Stream States</a>
</li>
<ul><li>3.1. <a href="#rfc.section.3.1">Sending Stream States</a>
</li>
<li>3.2. <a href="#rfc.section.3.2">Receiving Stream States</a>
</li>
<li>3.3. <a href="#rfc.section.3.3">Permitted Frame Types</a>
</li>
<li>3.4. <a href="#rfc.section.3.4">Bidirectional Stream States</a>
</li>
<li>3.5. <a href="#rfc.section.3.5">Solicited State Transitions</a>
</li>
</ul><li>4. <a href="#rfc.section.4">Flow Control</a>
</li>
<ul><li>4.1. <a href="#rfc.section.4.1">Data Flow Control</a>
</li>
<li>4.2. <a href="#rfc.section.4.2">Flow Credit Increments</a>
</li>
<li>4.3. <a href="#rfc.section.4.3">Handling Stream Cancellation</a>
</li>
<li>4.4. <a href="#rfc.section.4.4">Stream Final Size</a>
</li>
<li>4.5. <a href="#rfc.section.4.5">Controlling Concurrency</a>
</li>
</ul><li>5. <a href="#rfc.section.5">Connections</a>
</li>
<ul><li>5.1. <a href="#rfc.section.5.1">Connection ID</a>
</li>
<ul><li>5.1.1. <a href="#rfc.section.5.1.1">Issuing Connection IDs</a>
</li>
<li>5.1.2. <a href="#rfc.section.5.1.2">Consuming and Retiring Connection IDs</a>
</li>
</ul><li>5.2. <a href="#rfc.section.5.2">Matching Packets to Connections</a>
</li>
<ul><li>5.2.1. <a href="#rfc.section.5.2.1">Client Packet Handling</a>
</li>
<li>5.2.2. <a href="#rfc.section.5.2.2">Server Packet Handling</a>
</li>
</ul><li>5.3. <a href="#rfc.section.5.3">Life of a QUIC Connection</a>
</li>
<li>5.4. <a href="#rfc.section.5.4">Required Operations on Connections</a>
</li>
</ul><li>6. <a href="#rfc.section.6">Version Negotiation</a>
</li>
<ul><li>6.1. <a href="#rfc.section.6.1">Sending Version Negotiation Packets</a>
</li>
<li>6.2. <a href="#rfc.section.6.2">Handling Version Negotiation Packets</a>
</li>
<ul><li>6.2.1. <a href="#rfc.section.6.2.1">Version Negotiation Between Draft Versions</a>
</li>
</ul><li>6.3. <a href="#rfc.section.6.3">Using Reserved Versions</a>
</li>
</ul><li>7. <a href="#rfc.section.7">Cryptographic and Transport Handshake</a>
</li>
<ul><li>7.1. <a href="#rfc.section.7.1">Example Handshake Flows</a>
</li>
<li>7.2. <a href="#rfc.section.7.2">Negotiating Connection IDs</a>
</li>
<li>7.3. <a href="#rfc.section.7.3">Transport Parameters</a>
</li>
<ul><li>7.3.1. <a href="#rfc.section.7.3.1">Values of Transport Parameters for 0-RTT</a>
</li>
<li>7.3.2. <a href="#rfc.section.7.3.2">New Transport Parameters</a>
</li>
</ul><li>7.4. <a href="#rfc.section.7.4">Cryptographic Message Buffering</a>
</li>
</ul><li>8. <a href="#rfc.section.8">Address Validation</a>
</li>
<ul><li>8.1. <a href="#rfc.section.8.1">Address Validation During Connection Establishment</a>
</li>
<ul><li>8.1.1. <a href="#rfc.section.8.1.1">Address Validation using Retry Packets</a>
</li>
<li>8.1.2. <a href="#rfc.section.8.1.2">Address Validation for Future Connections</a>
</li>
<li>8.1.3. <a href="#rfc.section.8.1.3">Address Validation Token Integrity</a>
</li>
</ul><li>8.2. <a href="#rfc.section.8.2">Path Validation</a>
</li>
<li>8.3. <a href="#rfc.section.8.3">Initiating Path Validation</a>
</li>
<li>8.4. <a href="#rfc.section.8.4">Path Validation Responses</a>
</li>
<li>8.5. <a href="#rfc.section.8.5">Successful Path Validation</a>
</li>
<li>8.6. <a href="#rfc.section.8.6">Failed Path Validation</a>
</li>
</ul><li>9. <a href="#rfc.section.9">Connection Migration</a>
</li>
<ul><li>9.1. <a href="#rfc.section.9.1">Probing a New Path</a>
</li>
<li>9.2. <a href="#rfc.section.9.2">Initiating Connection Migration</a>
</li>
<li>9.3. <a href="#rfc.section.9.3">Responding to Connection Migration</a>
</li>
<ul><li>9.3.1. <a href="#rfc.section.9.3.1">Peer Address Spoofing</a>
</li>
<li>9.3.2. <a href="#rfc.section.9.3.2">On-Path Address Spoofing</a>
</li>
<li>9.3.3. <a href="#rfc.section.9.3.3">Off-Path Packet Forwarding</a>
</li>
</ul><li>9.4. <a href="#rfc.section.9.4">Loss Detection and Congestion Control</a>
</li>
<li>9.5. <a href="#rfc.section.9.5">Privacy Implications of Connection Migration</a>
</li>
<li>9.6. <a href="#rfc.section.9.6">Server’s Preferred Address</a>
</li>
<ul><li>9.6.1. <a href="#rfc.section.9.6.1">Communicating a Preferred Address</a>
</li>
<li>9.6.2. <a href="#rfc.section.9.6.2">Responding to Connection Migration</a>
</li>
<li>9.6.3. <a href="#rfc.section.9.6.3">Interaction of Client Migration and Preferred Address</a>
</li>
</ul><li>9.7. <a href="#rfc.section.9.7">Use of IPv6 Flow-Label and Migration</a>
</li>
</ul><li>10. <a href="#rfc.section.10">Connection Termination</a>
</li>
<ul><li>10.1. <a href="#rfc.section.10.1">Closing and Draining Connection States</a>
</li>
<li>10.2. <a href="#rfc.section.10.2">Idle Timeout</a>
</li>
<li>10.3. <a href="#rfc.section.10.3">Immediate Close</a>
</li>
<li>10.4. <a href="#rfc.section.10.4">Stateless Reset</a>
</li>
<ul><li>10.4.1. <a href="#rfc.section.10.4.1">Detecting a Stateless Reset</a>
</li>
<li>10.4.2. <a href="#rfc.section.10.4.2">Calculating a Stateless Reset Token</a>
</li>
<li>10.4.3. <a href="#rfc.section.10.4.3">Looping</a>
</li>
</ul></ul><li>11. <a href="#rfc.section.11">Error Handling</a>
</li>
<ul><li>11.1. <a href="#rfc.section.11.1">Connection Errors</a>
</li>
<li>11.2. <a href="#rfc.section.11.2">Stream Errors</a>
</li>
</ul><li>12. <a href="#rfc.section.12">Packets and Frames</a>
</li>
<ul><li>12.1. <a href="#rfc.section.12.1">Protected Packets</a>
</li>
<li>12.2. <a href="#rfc.section.12.2">Coalescing Packets</a>
</li>
<li>12.3. <a href="#rfc.section.12.3">Packet Numbers</a>
</li>
<li>12.4. <a href="#rfc.section.12.4">Frames and Frame Types</a>
</li>
</ul><li>13. <a href="#rfc.section.13">Packetization and Reliability</a>
</li>
<ul><li>13.1. <a href="#rfc.section.13.1">Packet Processing</a>
</li>
<li>13.2. <a href="#rfc.section.13.2">Generating Acknowledgements</a>
</li>
<ul><li>13.2.1. <a href="#rfc.section.13.2.1">Sending ACK Frames</a>
</li>
<li>13.2.2. <a href="#rfc.section.13.2.2">Managing ACK Ranges</a>
</li>
<li>13.2.3. <a href="#rfc.section.13.2.3">Receiver Tracking of ACK Frames</a>
</li>
<li>13.2.4. <a href="#rfc.section.13.2.4">Limiting ACK Ranges</a>
</li>
<li>13.2.5. <a href="#rfc.section.13.2.5">Measuring and Reporting Host Delay</a>
</li>
<li>13.2.6. <a href="#rfc.section.13.2.6">ACK Frames and Packet Protection</a>
</li>
</ul><li>13.3. <a href="#rfc.section.13.3">Retransmission of Information</a>
</li>
<li>13.4. <a href="#rfc.section.13.4">Explicit Congestion Notification</a>
</li>
<ul><li>13.4.1. <a href="#rfc.section.13.4.1">ECN Counts</a>
</li>
<li>13.4.2. <a href="#rfc.section.13.4.2">ECN Validation</a>
</li>
</ul></ul><li>14. <a href="#rfc.section.14">Packet Size</a>
</li>
<ul><li>14.1. <a href="#rfc.section.14.1">Path Maximum Transmission Unit (PMTU)</a>
</li>
<li>14.2. <a href="#rfc.section.14.2">ICMP Packet Too Big Messages</a>
</li>
<li>14.3. <a href="#rfc.section.14.3">Datagram Packetization Layer PMTU Discovery</a>
</li>
<ul><li>14.3.1. <a href="#rfc.section.14.3.1">PMTU Probes Containing Source Connection ID</a>
</li>
</ul></ul><li>15. <a href="#rfc.section.15">Versions</a>
</li>
<li>16. <a href="#rfc.section.16">Variable-Length Integer Encoding</a>
</li>
<li>17. <a href="#rfc.section.17">Packet Formats</a>
</li>
<ul><li>17.1. <a href="#rfc.section.17.1">Packet Number Encoding and Decoding</a>
</li>
<li>17.2. <a href="#rfc.section.17.2">Long Header Packets</a>
</li>
<ul><li>17.2.1. <a href="#rfc.section.17.2.1">Version Negotiation Packet</a>
</li>
<li>17.2.2. <a href="#rfc.section.17.2.2">Initial Packet</a>
</li>
<li>17.2.3. <a href="#rfc.section.17.2.3">0-RTT</a>
</li>
<li>17.2.4. <a href="#rfc.section.17.2.4">Handshake Packet</a>
</li>
<li>17.2.5. <a href="#rfc.section.17.2.5">Retry Packet</a>
</li>
</ul><li>17.3. <a href="#rfc.section.17.3">Short Header Packets</a>
</li>
<ul><li>17.3.1. <a href="#rfc.section.17.3.1">Latency Spin Bit</a>
</li>
</ul></ul><li>18. <a href="#rfc.section.18">Transport Parameter Encoding</a>
</li>
<ul><li>18.1. <a href="#rfc.section.18.1">Reserved Transport Parameters</a>
</li>
<li>18.2. <a href="#rfc.section.18.2">Transport Parameter Definitions</a>
</li>
</ul><li>19. <a href="#rfc.section.19">Frame Types and Formats</a>
</li>
<ul><li>19.1. <a href="#rfc.section.19.1">PADDING Frame</a>
</li>
<li>19.2. <a href="#rfc.section.19.2">PING Frame</a>
</li>
<li>19.3. <a href="#rfc.section.19.3">ACK Frames</a>
</li>
<ul><li>19.3.1. <a href="#rfc.section.19.3.1">ACK Ranges</a>
</li>
<li>19.3.2. <a href="#rfc.section.19.3.2">ECN Counts</a>
</li>
</ul><li>19.4. <a href="#rfc.section.19.4">RESET_STREAM Frame</a>
</li>
<li>19.5. <a href="#rfc.section.19.5">STOP_SENDING Frame</a>
</li>
<li>19.6. <a href="#rfc.section.19.6">CRYPTO Frame</a>
</li>
<li>19.7. <a href="#rfc.section.19.7">NEW_TOKEN Frame</a>
</li>
<li>19.8. <a href="#rfc.section.19.8">STREAM Frames</a>
</li>
<li>19.9. <a href="#rfc.section.19.9">MAX_DATA Frame</a>
</li>
<li>19.10. <a href="#rfc.section.19.10">MAX_STREAM_DATA Frame</a>
</li>
<li>19.11. <a href="#rfc.section.19.11">MAX_STREAMS Frames</a>
</li>
<li>19.12. <a href="#rfc.section.19.12">DATA_BLOCKED Frame</a>
</li>
<li>19.13. <a href="#rfc.section.19.13">STREAM_DATA_BLOCKED Frame</a>
</li>
<li>19.14. <a href="#rfc.section.19.14">STREAMS_BLOCKED Frames</a>
</li>
<li>19.15. <a href="#rfc.section.19.15">NEW_CONNECTION_ID Frame</a>
</li>
<li>19.16. <a href="#rfc.section.19.16">RETIRE_CONNECTION_ID Frame</a>
</li>
<li>19.17. <a href="#rfc.section.19.17">PATH_CHALLENGE Frame</a>
</li>
<li>19.18. <a href="#rfc.section.19.18">PATH_RESPONSE Frame</a>
</li>
<li>19.19. <a href="#rfc.section.19.19">CONNECTION_CLOSE Frames</a>
</li>
<li>19.20. <a href="#rfc.section.19.20">Extension Frames</a>
</li>
</ul><li>20. <a href="#rfc.section.20">Transport Error Codes</a>
</li>
<ul><li>20.1. <a href="#rfc.section.20.1">Application Protocol Error Codes</a>
</li>
</ul><li>21. <a href="#rfc.section.21">Security Considerations</a>
</li>
<ul><li>21.1. <a href="#rfc.section.21.1">Handshake Denial of Service</a>
</li>
<li>21.2. <a href="#rfc.section.21.2">Amplification Attack</a>
</li>
<li>21.3. <a href="#rfc.section.21.3">Optimistic ACK Attack</a>
</li>
<li>21.4. <a href="#rfc.section.21.4">Slowloris Attacks</a>
</li>
<li>21.5. <a href="#rfc.section.21.5">Stream Fragmentation and Reassembly Attacks</a>
</li>
<li>21.6. <a href="#rfc.section.21.6">Stream Commitment Attack</a>
</li>
<li>21.7. <a href="#rfc.section.21.7">Peer Denial of Service</a>
</li>
<li>21.8. <a href="#rfc.section.21.8">Explicit Congestion Notification Attacks</a>
</li>
<li>21.9. <a href="#rfc.section.21.9">Stateless Reset Oracle</a>
</li>
<li>21.10. <a href="#rfc.section.21.10">Version Downgrade</a>
</li>
<li>21.11. <a href="#rfc.section.21.11">Targeted Attacks by Routing</a>
</li>
</ul><li>22. <a href="#rfc.section.22">IANA Considerations</a>
</li>
<ul><li>22.1. <a href="#rfc.section.22.1">QUIC Transport Parameter Registry</a>
</li>
<li>22.2. <a href="#rfc.section.22.2">QUIC Frame Type Registry</a>
</li>
<li>22.3. <a href="#rfc.section.22.3">QUIC Transport Error Codes Registry</a>
</li>
</ul><li>23. <a href="#rfc.references">References</a>
</li>
<ul><li>23.1. <a href="#rfc.references.1">Normative References</a>
</li>
<li>23.2. <a href="#rfc.references.2">Informative References</a>
</li>
</ul><li>Appendix A. <a href="#rfc.appendix.A">Sample Packet Number Decoding Algorithm</a>
</li>
<li>Appendix B. <a href="#rfc.appendix.B">Change Log</a>
</li>
<ul><li>B.1. <a href="#rfc.appendix.B.1">Since draft-ietf-quic-transport-22</a>
</li>
<li>B.2. <a href="#rfc.appendix.B.2">Since draft-ietf-quic-transport-21</a>
</li>
<li>B.3. <a href="#rfc.appendix.B.3">Since draft-ietf-quic-transport-20</a>
</li>
<li>B.4. <a href="#rfc.appendix.B.4">Since draft-ietf-quic-transport-19</a>
</li>
<li>B.5. <a href="#rfc.appendix.B.5">Since draft-ietf-quic-transport-18</a>
</li>
<li>B.6. <a href="#rfc.appendix.B.6">Since draft-ietf-quic-transport-17</a>
</li>
<li>B.7. <a href="#rfc.appendix.B.7">Since draft-ietf-quic-transport-16</a>
</li>
<li>B.8. <a href="#rfc.appendix.B.8">Since draft-ietf-quic-transport-15</a>
</li>
<li>B.9. <a href="#rfc.appendix.B.9">Since draft-ietf-quic-transport-14</a>
</li>
<li>B.10. <a href="#rfc.appendix.B.10">Since draft-ietf-quic-transport-13</a>
</li>
<li>B.11. <a href="#rfc.appendix.B.11">Since draft-ietf-quic-transport-12</a>
</li>
<li>B.12. <a href="#rfc.appendix.B.12">Since draft-ietf-quic-transport-11</a>
</li>
<li>B.13. <a href="#rfc.appendix.B.13">Since draft-ietf-quic-transport-10</a>
</li>
<li>B.14. <a href="#rfc.appendix.B.14">Since draft-ietf-quic-transport-09</a>
</li>
<li>B.15. <a href="#rfc.appendix.B.15">Since draft-ietf-quic-transport-08</a>
</li>
<li>B.16. <a href="#rfc.appendix.B.16">Since draft-ietf-quic-transport-07</a>
</li>
<li>B.17. <a href="#rfc.appendix.B.17">Since draft-ietf-quic-transport-06</a>
</li>
<li>B.18. <a href="#rfc.appendix.B.18">Since draft-ietf-quic-transport-05</a>
</li>
<li>B.19. <a href="#rfc.appendix.B.19">Since draft-ietf-quic-transport-04</a>
</li>
<li>B.20. <a href="#rfc.appendix.B.20">Since draft-ietf-quic-transport-03</a>
</li>
<li>B.21. <a href="#rfc.appendix.B.21">Since draft-ietf-quic-transport-02</a>
</li>
<li>B.22. <a href="#rfc.appendix.B.22">Since draft-ietf-quic-transport-01</a>
</li>
<li>B.23. <a href="#rfc.appendix.B.23">Since draft-ietf-quic-transport-00</a>
</li>
<li>B.24. <a href="#rfc.appendix.B.24">Since draft-hamilton-quic-transport-protocol-01</a>
</li>
</ul><li><a href="#rfc.acknowledgments">Acknowledgments</a>
</li>
<li><a href="#rfc.contributors">Contributors</a>
</li>
<li><a href="#rfc.authors">Authors' Addresses</a>
</li>
</ul>
<h1 id="rfc.section.1">
<a href="#rfc.section.1">1.</a> <a href="#introduction" id="introduction">Introduction</a>
</h1>
<p id="rfc.section.1.p.1">QUIC is a multiplexed and secure general-purpose transport protocol that provides:</p>
<p></p>
<ul>
<li>Stream multiplexing</li>
<li>Stream and connection-level flow control</li>
<li>Low-latency connection establishment</li>
<li>Connection migration and resilience to NAT rebinding</li>
<li>Authenticated and encrypted header and payload</li>
</ul>
<p id="rfc.section.1.p.3">QUIC uses UDP as a substrate to avoid requiring changes to legacy client operating systems and middleboxes. QUIC authenticates all of its headers and encrypts most of the data it exchanges, including its signaling, to avoid incurring a dependency on middleboxes.</p>
<h2 id="rfc.section.1.1">
<a href="#rfc.section.1.1">1.1.</a> <a href="#document-structure" id="document-structure">Document Structure</a>
</h2>
<p id="rfc.section.1.1.p.1">This document describes the core QUIC protocol and is structured as follows.</p>
<p></p>
<ul>
<li>Streams are the basic service abstraction that QUIC provides. <ul>
<li>
<a href="#streams" class="xref">Section 2</a> describes core concepts related to streams,</li>
<li>
<a href="#stream-states" class="xref">Section 3</a> provides a reference model for stream states, and</li>
<li>
<a href="#flow-control" class="xref">Section 4</a> outlines the operation of flow control.</li>
</ul>
</li>
<li>Connections are the context in which QUIC endpoints communicate. <ul>
<li>
<a href="#connections" class="xref">Section 5</a> describes core concepts related to connections,</li>
<li>
<a href="#version-negotiation" class="xref">Section 6</a> describes version negotiation,</li>
<li>
<a href="#handshake" class="xref">Section 7</a> details the process for establishing connections,</li>
<li>
<a href="#address-validation" class="xref">Section 8</a> specifies critical denial of service mitigation mechanisms,</li>
<li>
<a href="#migration" class="xref">Section 9</a> describes how endpoints migrate a connection to a new network path,</li>
<li>
<a href="#termination" class="xref">Section 10</a> lists the options for terminating an open connection, and</li>
<li>
<a href="#error-handling" class="xref">Section 11</a> provides general guidance for error handling.</li>
</ul>
</li>
<li>Packets and frames are the basic unit used by QUIC to communicate. <ul>
<li>
<a href="#packets-frames" class="xref">Section 12</a> describes concepts related to packets and frames,</li>
<li>
<a href="#packetization" class="xref">Section 13</a> defines models for the transmission, retransmission, and acknowledgement of data, and</li>
<li>
<a href="#packet-size" class="xref">Section 14</a> specifies rules for managing the size of packets.</li>
</ul>
</li>
<li>Finally, encoding details of QUIC protocol elements are described in: <ul>
<li>
<a href="#versions" class="xref">Section 15</a> (Versions),</li>
<li>
<a href="#integer-encoding" class="xref">Section 16</a> (Integer Encoding),</li>
<li>
<a href="#packet-formats" class="xref">Section 17</a> (Packet Headers),</li>
<li>
<a href="#transport-parameter-encoding" class="xref">Section 18</a> (Transport Parameters),</li>
<li>
<a href="#frame-formats" class="xref">Section 19</a> (Frames), and</li>
<li>
<a href="#error-codes" class="xref">Section 20</a> (Errors).</li>
</ul>
</li>
</ul>
<p id="rfc.section.1.1.p.3">Accompanying documents describe QUIC’s loss detection and congestion control <a href="#QUIC-RECOVERY" class="xref">[QUIC-RECOVERY]</a>, and the use of TLS for key negotiation <a href="#QUIC-TLS" class="xref">[QUIC-TLS]</a>.</p>
<p id="rfc.section.1.1.p.4">This document defines QUIC version 1, which conforms to the protocol invariants in <a href="#QUIC-INVARIANTS" class="xref">[QUIC-INVARIANTS]</a>.</p>
<h2 id="rfc.section.1.2">
<a href="#rfc.section.1.2">1.2.</a> <a href="#terms-and-definitions" id="terms-and-definitions">Terms and Definitions</a>
</h2>
<p id="rfc.section.1.2.p.1">The keywords “MUST”, “MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”, “RECOMMENDED”, “NOT RECOMMENDED”, “MAY”, and “OPTIONAL” in this document are to be interpreted as described in BCP 14 <a href="#RFC2119" class="xref">[RFC2119]</a> <a href="#RFC8174" class="xref">[RFC8174]</a> when, and only when, they appear in all capitals, as shown here.</p>
<p id="rfc.section.1.2.p.2">Commonly used terms in the document are described below.</p>
<p></p>
<dl>
<dt>QUIC:</dt>