3Com SuperStack 3 NBX, Administrator'S Manual

Page: 443 / 496

Checking Connections 443
■
(It is normal for a first ping to fail and subsequent pings to
succeed).
■
Subsequent requests timed-out
■
(Indicates some packet loss. Rerun using the “-n 100” option. The
“request timed out” number represents the percentage of lost
packets. These packets could have been lost in either direction.)
b
Destination host not reachable
■
Ping couldn’t negotiate a path to the specified address
(
PC is not plugged into LAN, incorrect gateway address in route,
or a firewall blocked the ping).
c
Approximate round-trip times in milliseconds
■
Ping time greater than
10 ms
but preferably less than 300 ms.
(Ping times can differ because the network often routes individual
packets along different internal routes depending on congestion.)
4 Use
tracert
on the command line:
tracert <192.168.1.190>
(example IP address)
5 Interpret trace results:
The
tracert
command lists every IP gateway it encounters as it tries to
reach the specified destination. It also includes the number of times (3)
required to reach each intermediate gateway. If a network connection
failure occurred in route, this command indicates where it occurred.
Because the
tracert
command reveals the chain of logical connections
across a network, it can be useful for comparing the performance of
alternative internet service providers.
NetMeeting Connections
You can also check H.323 voice packets that are sent between systems
that are running Microsoft NetMeeting. ConneXtions software requires it
to run G.711 (CCITT mu-law) or G.723.1 compression. NetMeeting is
available on the Resource Pack CD, or it is available as a free download
from
www.microsoft.com
.
You can conduct the NetMeeting connect test from the operating system
that runs the ConneXtions software, or from another PC on the LAN.
You must run NetMeeting and ConneXtions on different PCs.