From owner-freebsd-net Fri Jan 21 10:39:14 2000 Delivered-To: freebsd-net@freebsd.org Received: from roam.psg.com (mg136-131.ricochet.net [204.179.136.131]) by hub.freebsd.org (Postfix) with ESMTP id 08B8214DE4 for ; Fri, 21 Jan 2000 10:33:40 -0800 (PST) (envelope-from randy@psg.com) Received: from randy by roam.psg.com with local (Exim 3.12 #1) id 12BisD-00057v-00 for freebsd-net@freebsd.org; Fri, 21 Jan 2000 10:33:29 -0800 From: Randy Bush MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit To: freebsd-net@freebsd.org Subject: backoff recovery? Message-Id: Date: Fri, 21 Jan 2000 10:33:29 -0800 Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org on a metricom in a san jose hotel. really bad link packet loss. stack's response to the poor link seemed a bit strange to me. so i sent the traces to some friends, and in discussion with vern, ... From: Vern Paxson To: Randy Bush > you may or not be interested in a trace. Interesting trace. I don't think the basic problem is SCP/SSH. From the look of it, there's (1) significant packet loss; (2) a bug in the TCP that it isn't collapsing down the exponentially backed-off timer after the retransmitted data is acked (this surprises me in a stack as mature as FreeBSD); (3) a shutdown bug in which one side gets stuck sending FINs and they don't elicit FIN-acks or RSTs (perhaps they're being dropped due to an erroneous conclusion that their timestamp is bad). It may be that SCP is suffering from more loses than FTP because it's not managing to packetize its data well, and that could in turn reflect interactions between crypto operations and buffering; but I don't know whether in the trace it actually makes it out of its initial crypto negotiation or not. Hmmmm, a thought: perhaps Metricom is particularly bad at dealing with bidirectional transfers, and the fact that SCP is doing that initially (and some of it collides, due to retransmissions, due in turn to the loss) means it does significantly worse than the unidirectional FTP data transfer, which also suffers from loss, but not as bad. Dunno ... Vern of course, the horrible link may be obscuring things. the traces ... 204.179.135.13 is 3.4+PAO 147.28.0.39 is 4.0-current a few weeks old 09:11:11.471846 204.179.135.13.970 > 147.28.0.39.22: F 2285079120:2285079120(0) ack 3637246625 win 17376 (DF) [tos 0x8] 09:11:14.929037 204.179.137.61.969 > 147.28.0.39.22: S 2415896350:2415896350(0) win 16384 (DF) 09:11:17.873883 204.179.137.61.969 > 147.28.0.39.22: S 2415896350:2415896350(0) win 16384 (DF) 09:11:18.175014 147.28.0.39.22 > 204.179.137.61.969: S 3786450220:3786450220(0) ack 2415896351 win 17376 (DF) 09:11:18.175116 204.179.137.61.969 > 147.28.0.39.22: . ack 1 win 17376 (DF) 09:11:18.285493 147.28.0.39.22 > 204.179.137.61.969: . ack 1 win 17376 (DF) 09:11:19.873923 204.179.135.13.970 > 147.28.0.39.22: F 0:0(0) ack 1 win 17376 (DF) [tos 0x8] 09:11:20.415333 147.28.0.39.22 > 204.179.137.61.969: P 1:16(15) ack 1 win 17376 (DF) [tos 0x10] 09:11:20.415768 204.179.137.61.969 > 147.28.0.39.22: P 1:16(15) ack 16 win 17376 (DF) [tos 0x10] 09:11:30.874292 204.179.137.61.969 > 147.28.0.39.22: P 1:16(15) ack 16 win 17376 (DF) [tos 0x10] 09:11:31.685822 147.28.0.39.22 > 204.179.137.61.969: P 16:292(276) ack 16 win 17376 (DF) [tos 0x10] 09:11:31.696890 147.28.0.39.22 > 204.179.137.61.969: . ack 16 win 17376 (DF) [tos 0x10] 09:11:31.711505 204.179.137.61.969 > 147.28.0.39.22: P 16:172(156) ack 292 win 17376 (DF) [tos 0x10] 09:11:35.495767 147.28.0.39.22 > 204.179.137.61.969: . ack 172 win 17376 (DF) [tos 0x10] 09:11:35.615775 147.28.0.39.22 > 204.179.137.61.969: P 292:304(12) ack 172 win 17376 (DF) [tos 0x10] 09:11:35.615964 204.179.137.61.969 > 147.28.0.39.22: P 172:192(20) ack 304 win 17376 (DF) [tos 0x10] 09:11:36.874418 204.179.135.13.970 > 147.28.0.39.22: F 0:0(0) ack 1 win 17376 (DF) [tos 0x8] 09:11:49.206191 147.28.0.39.22 > 204.179.137.61.969: P 304:376(72) ack 192 win 17376 (DF) [tos 0x10] 09:11:49.207551 204.179.137.61.969 > 147.28.0.39.22: P 192:348(156) ack 376 win 17376 (DF) [tos 0x10] 09:11:49.736176 147.28.0.39.22 > 204.179.137.61.969: P 376:516(140) ack 348 win 17376 (DF) [tos 0x10] 09:11:49.738303 147.28.0.39.22 > 204.179.137.61.969: P 516:528(12) ack 348 win 17376 (DF) [tos 0x10] 09:11:49.874830 204.179.137.61.969 > 147.28.0.39.22: . ack 528 win 17376 (DF) [tos 0x10] 09:11:58.731953 204.179.137.61.1323 > 192.96.22.18.25: S 2424678315:2424678315(0) win 16384 (DF) 09:12:00.266387 192.96.22.18.25 > 204.179.137.61.1323: R 0:0(0) ack 2424678316 win 0 09:12:10.875442 204.179.135.13.970 > 147.28.0.39.22: F 0:0(0) ack 1 win 17376 (DF) [tos 0x8] 09:12:12.761727 204.179.137.61.969 > 147.28.0.39.22: P 348:376(28) ack 528 win 17376 (DF) [tos 0x10] 09:12:13.176893 147.28.0.39.22 > 204.179.137.61.969: P 528:540(12) ack 376 win 17376 (DF) [tos 0x10] 09:12:13.178538 204.179.137.61.969 > 147.28.0.39.22: P 376:412(36) ack 540 win 17376 (DF) [tos 0x8] 09:12:13.666890 147.28.0.39.22 > 204.179.137.61.969: . ack 412 win 17376 (DF) [tos 0x8] 09:12:13.666948 204.179.137.61.969 > 147.28.0.39.22: P 412:432(20) ack 540 win 17376 (DF) [tos 0x8] 09:12:33.876076 204.179.137.61.969 > 147.28.0.39.22: P 412:432(20) ack 540 win 17376 (DF) [tos 0x8] 09:12:37.417574 147.28.0.39.22 > 204.179.137.61.969: . ack 432 win 17376 (DF) [tos 0x8] 09:12:42.677739 147.28.0.39.22 > 204.179.137.61.969: P 540:584(44) ack 432 win 17376 (DF) [tos 0x8] 09:12:42.678810 204.179.137.61.969 > 147.28.0.39.22: P 432:452(20) ack 584 win 17376 (DF) [tos 0x8] 09:12:58.876825 204.179.137.61.969 > 147.28.0.39.22: P 432:452(20) ack 584 win 17376 (DF) [tos 0x8] 09:13:02.168295 147.28.0.39.22 > 204.179.137.61.969: . ack 452 win 17376 (DF) [tos 0x8] 09:13:14.877260 204.179.135.13.970 > 147.28.0.39.22: F 0:0(0) ack 1 win 17376 (DF) [tos 0x8] 09:13:37.277965 204.179.137.61.123 > 129.250.0.49.123: v4 client strat 4 poll 10 prec -28 09:13:53.819596 207.126.101.100.119 > 204.179.130.75.1231: P 1183230998:1183231406(408) ack 57933214 win 33768 (DF) 09:13:53.819647 207.126.101.100.119 > 204.179.130.75.1231: P 0:408(408) ack 1 win 33768 (DF) 09:13:58.754096 204.179.137.61.1324 > 192.96.22.18.25: S 2448056994:2448056994(0) win 16384 (DF) 09:14:01.378531 204.179.137.61.1324 > 192.96.22.18.25: S 2448056994:2448056994(0) win 16384 (DF) 09:14:05.299848 192.96.22.18.25 > 204.179.137.61.1324: R 0:0(0) ack 2448056995 win 0 09:14:18.879117 204.179.135.13.970 > 147.28.0.39.22: F 0:0(0) ack 1 win 17376 (DF) [tos 0x8] 09:14:26.279371 204.179.137.61.123 > 129.250.0.27.123: v4 client strat 4 poll 10 prec -28 09:14:26.650471 129.250.0.27.123 > 204.179.137.61.123: v4 server strat 2 poll 10 prec -24 09:14:28.279422 204.179.137.61.123 > 129.250.0.10.123: v4 client strat 4 poll 10 prec -28 09:14:28.970534 129.250.0.10.123 > 204.179.137.61.123: v4 server strat 2 poll 10 prec -24 09:14:42.279827 204.179.137.61.123 > 129.250.0.49.123: v4 client strat 4 poll 6 prec -28 09:14:42.980932 129.250.0.49.123 > 204.179.137.61.123: v4 server strat 2 poll 6 prec -24 09:15:22.880975 204.179.135.13.970 > 147.28.0.39.22: F 0:0(0) ack 1 win 17376 (DF) [tos 0x8] 09:15:47.281680 204.179.137.61.123 > 129.250.0.49.123: v4 client strat 4 poll 6 prec -28 09:15:47.972895 129.250.0.49.123 > 204.179.137.61.123: v4 server strat 2 poll 6 prec -24 09:15:58.777625 204.179.137.61.1325 > 192.96.22.18.25: S 2470865643:2470865643(0) win 16384 (DF) 09:16:01.382000 204.179.137.61.1325 > 192.96.22.18.25: S 2470865643:2470865643(0) win 16384 (DF) 09:16:05.243302 192.96.22.18.25 > 204.179.137.61.1325: R 0:0(0) ack 2470865644 win 0 09:16:26.882813 204.179.135.13.970 > 147.28.0.39.22: F 0:0(0) ack 1 win 17376 (DF) [tos 0x8] 09:16:35.283077 204.179.137.61.123 > 129.250.0.27.123: v4 client strat 4 poll 7 prec -28 09:16:38.283160 204.179.137.61.123 > 129.250.0.10.123: v4 client strat 4 poll 7 prec -28 09:16:38.843426 129.250.0.10.123 > 204.179.137.61.123: v4 server strat 3 poll 7 prec -24 09:16:53.283585 204.179.137.61.123 > 129.250.0.49.123: v4 client strat 4 poll 6 prec -28 09:17:30.884691 204.179.135.13.970 > 147.28.0.39.22: F 0:0(0) ack 1 win 17376 (DF) [tos 0x8] 09:17:58.800710 204.179.137.61.1326 > 192.96.22.18.25: S 2493553322:2493553322(0) win 16384 (DF) 09:17:59.836675 192.96.22.18.25 > 204.179.137.61.1326: R 0:0(0) ack 2493553323 win 0 09:18:34.886513 204.179.135.13.970 > 147.28.0.39.22: F 0:0(0) ack 1 win 17376 (DF) [tos 0x8] 09:18:38.958300 204.179.137.61 > 147.28.0.39: icmp: echo request 09:18:39.517785 147.28.0.39 > 204.179.137.61: icmp: echo reply 09:18:39.976600 204.179.137.61 > 147.28.0.39: icmp: echo request 09:18:40.986641 204.179.137.61 > 147.28.0.39: icmp: echo request 09:18:41.996658 204.179.137.61 > 147.28.0.39: icmp: echo request 09:18:43.006690 204.179.137.61 > 147.28.0.39: icmp: echo request 09:18:44.016721 204.179.137.61 > 147.28.0.39: icmp: echo request 09:18:44.297894 147.28.0.39 > 204.179.137.61: icmp: echo reply 09:18:47.099336 147.28.0.39 > 204.179.137.61: icmp: echo reply 09:18:47.118111 147.28.0.39 > 204.179.137.61: icmp: echo reply 09:19:38.888379 204.179.135.13.970 > 147.28.0.39.22: F 0:0(0) ack 1 win 17376 (DF) [tos 0x8] 09:19:58.824681 204.179.137.61.1327 > 192.96.22.18.25: S 2517030525:2517030525(0) win 16384 (DF) 09:20:00.010189 192.96.22.18.25 > 204.179.137.61.1327: R 0:0(0) ack 2517030526 win 0 but ftp makes it through, albeit barely 09:20:42.890232 204.179.135.13.970 > 147.28.0.39.22: F 0:0(0) ack 1 win 17376 (DF) [tos 0x8] 09:21:46.892088 204.179.135.13.970 > 147.28.0.39.22: F 0:0(0) ack 1 win 17376 (DF) [tos 0x8] 09:21:58.848083 204.179.137.61.1328 > 192.96.22.18.25: S 2540143257:2540143257(0) win 16384 (DF) 09:22:01.392409 204.179.137.61.1328 > 192.96.22.18.25: S 2540143257:2540143257(0) win 16384 (DF) 09:22:02.813651 192.96.22.18.25 > 204.179.137.61.1328: R 0:0(0) ack 2540143258 win 0 09:22:20.090484 204.179.137.61.969 > 147.28.0.39.22: F 452:452(0) ack 584 win 17376 (DF) [tos 0x8] 09:22:23.284492 147.28.0.39.22 > 204.179.137.61.969: . ack 453 win 17376 (DF) [tos 0x8] 09:22:24.205432 204.179.137.61.1329 > 147.28.0.39.21: S 2544965268:2544965268(0) win 16384 (DF) 09:22:26.893202 204.179.137.61.1329 > 147.28.0.39.21: S 2544965268:2544965268(0) win 16384 (DF) 09:22:30.144783 147.28.0.39.21 > 204.179.137.61.1329: . ack 2544965269 win 17376 (DF) 09:22:30.154422 147.28.0.39.21 > 204.179.137.61.1329: S 3931814626:3931814626(0) ack 2544965269 win 17376 (DF) 09:22:30.154508 204.179.137.61.1329 > 147.28.0.39.21: . ack 1 win 17376 (DF) 09:22:30.714829 147.28.0.39.21 > 204.179.137.61.1329: P 1:53(52) ack 1 win 17376 (DF) [tos 0x10] 09:22:30.893378 204.179.137.61.1329 > 147.28.0.39.21: . ack 53 win 17376 (DF) [tos 0x10] 09:22:50.893919 204.179.135.13.970 > 147.28.0.39.22: R 1:1(0) ack 1 win 17376 (DF) [tos 0x8] 09:22:51.148182 204.179.137.61.1329 > 147.28.0.39.21: P 1:13(12) ack 53 win 17376 (DF) [tos 0x10] 09:22:51.635314 147.28.0.39.21 > 204.179.137.61.1329: P 53:87(34) ack 13 win 17376 (DF) [tos 0x10] 09:22:51.693838 204.179.137.61.1329 > 147.28.0.39.21: . ack 87 win 17376 (DF) [tos 0x10] 09:22:55.495193 204.179.137.61.1329 > 147.28.0.39.21: P 13:28(15) ack 87 win 17376 (DF) [tos 0x10] 09:22:55.965439 147.28.0.39.21 > 204.179.137.61.1329: P 87:114(27) ack 28 win 17376 (DF) [tos 0x10] 09:22:55.966317 204.179.137.61.1329 > 147.28.0.39.21: P 28:34(6) ack 114 win 17376 (DF) [tos 0x10] 09:22:56.435456 147.28.0.39.21 > 204.179.137.61.1329: P 114:153(39) ack 34 win 17376 (DF) [tos 0x10] 09:22:56.493980 204.179.137.61.1329 > 147.28.0.39.21: . ack 153 win 17376 (DF) [tos 0x10] 09:23:15.104327 204.179.137.61.1329 > 147.28.0.39.21: P 34:42(8) ack 153 win 17376 (DF) [tos 0x10] 09:23:27.894970 204.179.137.61.1329 > 147.28.0.39.21: P 34:42(8) ack 153 win 17376 (DF) [tos 0x10] 09:23:28.326360 147.28.0.39.21 > 204.179.137.61.1329: P 153:173(20) ack 42 win 17376 (DF) [tos 0x10] 09:23:28.326557 204.179.137.61.1329 > 147.28.0.39.21: P 42:62(20) ack 173 win 17376 (DF) [tos 0x10] 09:23:40.395254 204.179.137.61.1329 > 147.28.0.39.21: P 42:62(20) ack 173 win 17376 (DF) [tos 0x10] 09:23:42.266777 147.28.0.39.21 > 204.179.137.61.1329: . ack 62 win 17376 (DF) [tos 0x10] 09:23:58.871382 204.179.137.61.1330 > 192.96.22.18.25: S 2562807967:2562807967(0) win 16384 (DF) 09:23:59.067279 147.28.0.39.21 > 204.179.137.61.1329: P 173:184(11) ack 62 win 17376 (DF) [tos 0x10] 09:23:59.067644 204.179.137.61.1329 > 147.28.0.39.21: P 62:89(27) ack 184 win 17376 (DF) [tos 0x10] 09:23:59.757321 147.28.0.39.21 > 204.179.137.61.1329: P 184:214(30) ack 89 win 17376 (DF) [tos 0x10] 09:23:59.758237 204.179.137.61.1329 > 147.28.0.39.21: P 89:109(20) ack 214 win 17376 (DF) [tos 0x10] 09:24:01.395876 204.179.137.61.1330 > 192.96.22.18.25: S 2562807967:2562807967(0) win 16384 (DF) 09:24:03.067125 147.28.0.39.20 > 204.179.137.61.49152: S 3952726335:3952726335(0) win 16384 (DF) [tos 0x8] 09:24:03.067248 204.179.137.61.49152 > 147.28.0.39.20: S 2563803235:2563803235(0) ack 3952726336 win 17376 (DF) 09:24:05.867269 192.96.22.18.25 > 204.179.137.61.1330: R 0:0(0) ack 2562807968 win 0 09:24:05.877391 147.28.0.39.20 > 204.179.137.61.49152: S 3952726335:3952726335(0) win 16384 (DF) [tos 0x8] 09:24:05.877468 204.179.137.61.49152 > 147.28.0.39.20: . ack 1 win 17376 (DF) 09:24:05.887512 147.28.0.39.20 > 204.179.137.61.49152: . ack 1 win 17376 (DF) [tos 0x8] 09:24:05.907514 147.28.0.39.21 > 204.179.137.61.1329: P 214:290(76) ack 109 win 17376 (DF) [tos 0x10] 09:24:06.096008 204.179.137.61.1329 > 147.28.0.39.21: . ack 290 win 17376 (DF) [tos 0x10] 09:24:38.078387 147.28.0.39.21 > 204.179.137.61.1329: P 290:314(24) ack 109 win 17376 (DF) [tos 0x10] 09:24:38.096911 204.179.137.61.1329 > 147.28.0.39.21: . ack 314 win 17352 (DF) [tos 0x10] 09:25:58.894426 204.179.137.61.1331 > 192.96.22.18.25: S 2586126435:2586126435(0) win 16384 (DF) 09:26:01.399330 204.179.137.61.1331 > 192.96.22.18.25: S 2586126435:2586126435(0) win 16384 (DF) 09:26:05.330634 192.96.22.18.25 > 204.179.137.61.1331: R 0:0(0) ack 2586126436 win 0 09:27:58.919306 204.179.137.61.1332 > 192.96.22.18.25: S 2609119057:2609119057(0) win 16384 (DF) 09:28:01.902863 204.179.137.61.1332 > 192.96.22.18.25: S 2609119057:2609119057(0) win 16384 (DF) 09:28:07.903038 204.179.137.61.1332 > 192.96.22.18.25: S 2609119057:2609119057(0) win 16384 (DF) 09:28:19.903405 204.179.137.61.1332 > 192.96.22.18.25: S 2609119057:2609119057(0) win 16384 (DF) 09:28:30.535320 147.28.0.39.20 > 204.179.137.61.49152: . 1:1449(1448) ack 1 win 17376 (DF) [tos 0x8] 09:28:30.703622 204.179.137.61.49152 > 147.28.0.39.20: . ack 1449 win 17376 (DF) [tos 0x8] 09:28:31.975336 147.28.0.39.20 > 204.179.137.61.49152: . 1449:2897(1448) ack 1 win 17376 (DF) [tos 0x8] 09:28:32.103677 204.179.137.61.49152 > 147.28.0.39.20: . ack 2897 win 17376 (DF) [tos 0x8] 09:28:32.225899 147.28.0.39.20 > 204.179.137.61.49152: . 2897:4345(1448) ack 1 win 17376 (DF) [tos 0x8] 09:28:32.303662 204.179.137.61.49152 > 147.28.0.39.20: . ack 4345 win 17376 (DF) [tos 0x8] 09:28:33.265474 147.28.0.39.20 > 204.179.137.61.49152: . 4345:5793(1448) ack 1 win 17376 (DF) [tos 0x8] 09:28:33.303715 204.179.137.61.49152 > 147.28.0.39.20: . ack 5793 win 17376 (DF) [tos 0x8] 09:28:33.525895 147.28.0.39.20 > 204.179.137.61.49152: . 5793:7241(1448) ack 1 win 17376 (DF) [tos 0x8] 09:28:33.703704 204.179.137.61.49152 > 147.28.0.39.20: . ack 7241 win 17376 (DF) [tos 0x8] 09:28:34.445361 147.28.0.39.20 > 204.179.137.61.49152: . 7241:8689(1448) ack 1 win 17376 (DF) [tos 0x8] 09:28:34.503725 204.179.137.61.49152 > 147.28.0.39.20: . ack 8689 win 17376 (DF) [tos 0x8] 09:28:34.835355 147.28.0.39.20 > 204.179.137.61.49152: . 8689:10137(1448) ack 1 win 17376 (DF) [tos 0x8] 09:28:34.903840 204.179.137.61.49152 > 147.28.0.39.20: . ack 10137 win 17376 (DF) [tos 0x8] 09:28:35.445385 147.28.0.39.20 > 204.179.137.61.49152: . 10137:11585(1448) ack 1 win 17376 (DF) [tos 0x8] 09:28:35.503752 204.179.137.61.49152 > 147.28.0.39.20: . ack 11585 win 17376 (DF) [tos 0x8] 09:28:36.615475 147.28.0.39.20 > 204.179.137.61.49152: . 11585:13033(1448) ack 1 win 17376 (DF) [tos 0x8] 09:28:36.703808 204.179.137.61.49152 > 147.28.0.39.20: . ack 13033 win 17376 (DF) [tos 0x8] 09:28:37.206061 147.28.0.39.20 > 204.179.137.61.49152: . 13033:14481(1448) ack 1 win 17376 (DF) [tos 0x8] 09:28:37.303826 204.179.137.61.49152 > 147.28.0.39.20: . ack 14481 win 17376 (DF) [tos 0x8] 09:28:37.465458 147.28.0.39.20 > 204.179.137.61.49152: . 14481:15929(1448) ack 1 win 17376 (DF) [tos 0x8] 09:28:37.503830 204.179.137.61.49152 > 147.28.0.39.20: . ack 15929 win 17376 (DF) [tos 0x8] 09:28:37.735460 147.28.0.39.20 > 204.179.137.61.49152: . 15929:17377(1448) ack 1 win 17376 (DF) [tos 0x8] 09:28:37.903925 204.179.137.61.49152 > 147.28.0.39.20: . ack 17377 win 17376 (DF) [tos 0x8] 09:28:38.335467 147.28.0.39.20 > 204.179.137.61.49152: . 17377:18825(1448) ack 1 win 17376 (DF) [tos 0x8] 09:28:38.503862 204.179.137.61.49152 > 147.28.0.39.20: . ack 18825 win 17376 (DF) [tos 0x8] 09:28:38.745216 147.28.0.39.20 > 204.179.137.61.49152: FP 18825:20248(1423) ack 1 win 17376 (DF) [tos 0x8] 09:28:38.745297 204.179.137.61.49152 > 147.28.0.39.20: . ack 20249 win 15953 (DF) [tos 0x8] 09:28:38.746658 204.179.137.61.49152 > 147.28.0.39.20: F 1:1(0) ack 20249 win 17376 (DF) [tos 0x8] 09:28:38.746937 204.179.137.61.1329 > 147.28.0.39.21: P 109:129(20) ack 314 win 17376 (DF) [tos 0x10] 09:28:39.405454 147.28.0.39.20 > 204.179.137.61.49152: . ack 2 win 17376 (DF) [tos 0x8] 09:28:39.415372 147.28.0.39.21 > 204.179.137.61.1329: P 314:334(20) ack 129 win 17376 (DF) [tos 0x10] 09:28:39.503877 204.179.137.61.1329 > 147.28.0.39.21: . ack 334 win 17376 (DF) [tos 0x10] 09:28:43.904094 204.179.137.61.1332 > 192.96.22.18.25: S 2609119057:2609119057(0) win 16384 (DF) randy To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message