BEAME@MCMASTER.BITNET.UUCP (03/02/87)
The following is a trace (excelan monitor) of a PC communicating to a GPX
micro-vax running ULTRIX. The ethernet is < 1% loaded, the GPX has no other
users on it. CFB/IN is packets going to the PC, CFB/OUT is packets going to
the uVax. The command executed is "cat file". The first number in the form
xxx.xxx is the time since the first packet in milli.micro seconds, the
second number is the time since the last packet in milli.mico seconds.
QUESTION:
Why does Ultrix wait about 5 seconds after the PC ACK's to send it's
next packet? Remember there are no gateways and almost noload on the
network or GPX.
1 : CFB/IN
ether: IP aa-00-04-00-07-04 -> 02-60-8c-10-46-46 140 0.000 0.000
ip: TCP 01.00001f -> 01.004646
tcp: TELNET -> 7464 ACK
tcp: seq: 64807377 ack: 40 win: 4096 len: 82
0: 66 20 25 66 20 25 66 20 25 66 20 25 75 20 25 75 |f %f %f %f %u %u|
16: 20 25 75 22 2c 26 58 6d 69 6e 2c 26 58 6d 61 78 | %u",&Xmin,&Xmax|
32: 2c 26 59 6d 69 6e 2c 26 59 6d 61 78 2c 26 44 65 |,&Ymin,&Ymax,&De|
48: 70 74 68 2c 26 47 72 69 64 78 2c 26 47 72 69 64 |pth,&Gridx,&Grid|
64: 79 29 3b 0d 0a 20 20 20 20 20 20 20 20 64 69 73 |y);.. dis|
80: 70 6c |pl |
2 : CFB/OUT
ether: IP 02-60-8c-10-46-46 -> aa-00-04-00-07-04 64 6.981 6.981
ip: TCP 01.004646 -> 01.00001f
tcp: 7464 -> TELNET ACK
tcp: seq: 40 ack: 64807459 win: 82 len: 0
3 : CFB/IN
ether: IP aa-00-04-00-07-04 -> 02-60-8c-10-46-46 140 4998.996 ***.***
ip: TCP 01.00001f -> 01.004646
tcp: TELNET -> 7464 ACK
tcp: seq: 64807459 ack: 40 win: 4096 len: 82
0: 61 79 20 3d 20 58 4f 70 65 6e 44 69 73 70 6c 61 |ay = XOpenDispla|
16: 79 28 4e 55 4c 4c 29 3b 0d 0a 20 20 20 20 20 20 |y(NULL);.. |
32: 20 20 77 20 3d 20 58 43 72 65 61 74 65 57 69 6e | w = XCreateWin|
48: 64 6f 77 28 52 6f 6f 74 57 69 6e 64 6f 77 2c 31 |dow(RootWindow,1|
64: 2c 31 2c 47 72 69 64 78 2c 47 72 69 64 79 2c 31 |,1,Gridx,Gridy,1|
80: 2c 57 |,W |
4 : CFB/OUT
ether: IP 02-60-8c-10-46-46 -> aa-00-04-00-07-04 64 5006.198 7.203
ip: TCP 01.004646 -> 01.00001f
tcp: 7464 -> TELNET ACK
tcp: seq: 40 ack: 64807541 win: 82 len: 0
5 : CFB/IN
ether: IP aa-00-04-00-07-04 -> 02-60-8c-10-46-46 140 9998.735 ***.***
ip: TCP 01.00001f -> 01.004646
tcp: TELNET -> 7464 ACK
tcp: seq: 64807541 ack: 40 win: 4096 len: 82
0: 68 69 74 65 50 69 78 6d 61 70 2c 42 6c 61 63 6b |hitePixmap,Black|
16: 50 69 78 6d 61 70 29 3b 0d 0a 20 20 20 20 20 20 |Pixmap);.. |
32: 20 20 58 4d 61 70 57 69 6e 64 6f 77 28 77 29 3b | XMapWindow(w);|
48: 0d 0a 20 20 20 20 20 20 20 20 58 53 65 6c 65 63 |.. XSelec|
64: 74 49 6e 70 75 74 28 77 2c 30 78 30 33 38 30 29 |tInput(w,0x0380)|
80: 3b 0d |;. |
Thanks in advance,
Carl BeameBEAME@MCMASTER.BITNET.UUCP (03/03/87)
Hello,
Thanks to everyone who responded to my query. To those who
suggested that I set the minimum window size to the maximum window size
for the PC/IP, this method will send two ACK's for every packet. But it
should work.
The real answer is to have the PC/IP send the "maximum segment option"
on connect to be the same as the PC's maximum window.
Thanks again to every one,
Carl Beame