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  From: Darryl Ross <darryl@bachblue.com.au>
  To  : LinuxSA <linuxsa@linuxsa.org.au>
  Date: Wed, 3 Mar 1999 23:26:27 +1030

Modem Problems

Hey All,

I've got the same problem Alan K was having with his modems. IE, it seems to
be buffering the data for 8 seconds, and then sending, or receiving it all
at once. The modem is one I bought off Alan that he had only used for one
day. While it was "stuffing up" I pinged the gateway machine for my ppp link
at my ISP, and here's the results I got:


PING 210.8.138.7 (210.8.138.7): 56 data bytes
64 bytes from 210.8.138.7: icmp_seq=0 ttl=64 time=5507.5 ms
64 bytes from 210.8.138.7: icmp_seq=1 ttl=64 time=4540.4 ms
64 bytes from 210.8.138.7: icmp_seq=2 ttl=64 time=3562.1 ms
64 bytes from 210.8.138.7: icmp_seq=3 ttl=64 time=2590.3 ms
64 bytes from 210.8.138.7: icmp_seq=4 ttl=64 time=1610.3 ms
64 bytes from 210.8.138.7: icmp_seq=5 ttl=64 time=630.4 ms
64 bytes from 210.8.138.7: icmp_seq=6 ttl=64 time=170.3 ms
64 bytes from 210.8.138.7: icmp_seq=7 ttl=64 time=7710.4 ms
64 bytes from 210.8.138.7: icmp_seq=8 ttl=64 time=6740.3 ms
64 bytes from 210.8.138.7: icmp_seq=9 ttl=64 time=5770.2 ms
64 bytes from 210.8.138.7: icmp_seq=10 ttl=64 time=4790.3 ms
64 bytes from 210.8.138.7: icmp_seq=11 ttl=64 time=3810.3 ms
64 bytes from 210.8.138.7: icmp_seq=12 ttl=64 time=2840.2 ms
64 bytes from 210.8.138.7: icmp_seq=13 ttl=64 time=1860.3 ms
64 bytes from 210.8.138.7: icmp_seq=14 ttl=64 time=880.3 ms
64 bytes from 210.8.138.7: icmp_seq=15 ttl=64 time=170.4 ms

--- 210.8.138.7 ping statistics ---
21 packets transmitted, 16 packets received, 23% packet loss
round-trip min/avg/max = 170.3/3324.0/7710.4 ms


As you can see, it seems to be 'holding' the data for 8 seconds before
sending it back. As I was pinging the actual machine on the other end of my
phone call, I think that I can rule out any routing problems, etc, etc, as
there is only the two machines, and modems between, to cause the problem,
and I haven't had this problem before. The only thing I have done is put the
new modem in. It was only connected for 2½ days before the problem showed
up.

Incidently, 64 bytes per second for 8 seconds makes 512 bytes of data.
What's the buffer on the modems? I'm wondering if it can be a problem with
this model? Alan said to me when I bought it off him that they were all
pretty much identical modems. The particular modem I bought off Alan is a
non-PnP Internal Discovery 33.6K modem, with voice support and SAVD. Anyone
else had a problem with this model, or very similar models?

Now that I think I have tracked the problem down some more, does anyone know
what we can do about it?

Cheers,
Dazz


--

All of Life's mysteries are on your TV
# 37. When they are alone, all foreigners prefer to speak English to each
other.




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