[HECnet] More TCP/IP stuff

[Johnny Billquist]

To continue my night ramblings about TCP/IP, I think I now have all aspect of my rewritten TCP/IP for RSX working right.
And to give you something of a live example from a real PDP-11/93, here is a tcpdump of a short session, which also gives you a little idea of response times for real hardware.

iMac is a pretty quick Mac. Pondus is my home 11/93. DELQA-YM, and also a VSV-21 which keeps the bus a little busy, but otherwise a farily idle machine when the test was run.

02:08:51.963513 IP iMac.61712 > Pondus.http: Flags [S], seq 1430632358, win 65535, options [mss 1460,nop,wscale 4,nop,nop,TS val 2339561691 ecr 0,sackOK,eol], length 0
02:08:52.041339 IP Pondus.http > iMac.61712: Flags [S.], seq 3396663417, ack 1430632359, win 5840, options [mss 1460], length 0
02:08:52.041397 IP iMac.61712 > Pondus.http: Flags [.], ack 1, win 65535, length 0
02:09:14.525188 IP iMac.61712 > Pondus.http: Flags [P.], seq 1:17, ack 1, win 65535, length 16
02:09:14.729046 IP Pondus.http > iMac.61712: Flags [.], ack 17, win 5840, length 0
02:09:14.964597 IP iMac.61712 > Pondus.http: Flags [P.], seq 17:19, ack 1, win 65535, length 2
02:09:15.169279 IP Pondus.http > iMac.61712: Flags [.], ack 19, win 5840, length 0
02:09:16.372880 IP Pondus.http > iMac.61712: Flags [F.], seq 1:1272, ack 19, win 5840, length 1271
02:09:16.372949 IP iMac.61712 > Pondus.http: Flags [.], ack 1273, win 65535, length 0
02:09:16.373569 IP iMac.61712 > Pondus.http: Flags [F.], seq 19, ack 1273, win 65535, length 0
02:09:16.389006 IP Pondus.http > iMac.61712: Flags [.], ack 20, win 5840, length 0


So, for the initial SYN-ACK response to the SYN is about 8/100s, which I think is pretty ok (that would include the startup of the web server task). It takes a little time to serve the data requested in the HTTP session. Not surprising since the web server needs to be started, it needs to read in the request from the net, parse it, log it to a couple of different logs, access the mapping between URL and filenames, access the mime content mapping, read the requested file, and send the stuff back over the network.
(And I typed in the http request by hand.)
All in all, the session took 25 seconds.

Time to maybe twiddle some HLL libraries a little more, and start thinking of getting this onto some more machines than mine...

	Johnny

-- 
Johnny Billquist                                   || "I'm on a bus
                                                                  ||   on a psychedelic trip
email: bqt at softjar.se                         ||   Reading murder books
pdp is alive!                                         ||   tryin' to stay hip" - B. Idol