[NTISP] Slow Telnet Connections

Greg White ( GWhite@bctelco.com )
Thu, 22 Jul 1999 08:11:59 -0700


I have a couple of v.90 dialup customers that are experiencing slow and
choppy telnet connections when attempting to access sites outside of our
local network. We verified that the destination servers were up and not
under heavy load through a direct dialup connection into those boxes. When
we access this server through another provider, the connection is smooth.
Access to local hosts via Telnet is just fine.

The network between us and the destination system appears to be very clean.
When I trace the route from the terminal servers to the destination, there
is no packet loss, and the ping times are below 40 ms. The slow and choppy
behavior seems to happen at any time during the day. Even during peak
times, our T1 is only at about 15% utilization.

We are using Cisco AS5200s for our dialup servers (IOS 12.0(5), mica modem
rev 2.7.1), and a Cisco 1601 (don't laugh, I have a 7206 on the way) for the
router connecting us to our provider. The router IOS is 11.3(5)T. The
router runs about 25% CPU usage. It is running access lists to prevent ip
spoofing, and it was configured to disallow inbound telnet sessions.
Removing the access lists had no effect.

Has anyone experienced this, or do you have any ideas what could be causing
it? Anyone know of any problems with the router or AS5200 that could be
attributing to this? We have seen the same behavior with two completely
independent sites now.


Greg White
ISP Network Administrator
Beavercreek Cooperative Telephone Company

For more information about this list (including removal) go to: