HP ProCurve 10 Installation Manual page 35

• 100Base-T topology rules: Be aware that the topology rules for
100Base-T networks are much more restrictive than for 10Base-T.
You may have to redo an existing 10Base-T topology for 100Base-T
products.
The HP 10/100 hubs operate as Class II hubs when being used for
100Base-T networking. Some basic Class II 100Base-T Hub rules are
as follows:
– The maximum segment length for a hub-to-end node connection
is 100 meters.
– At most one hub can be cascaded from any of the hub ports that
are operating at 100 Mbps.
– Do not mix Class I and Class II hubs when cascading.
– When cascading two hubs together, the maximum distance sepa-
rating them is 5 meters.
– You must use 100-ohm Category 5 UTP cable in the 100Base-T
installations.
See the card "Connectivity Rules for 100T Networks" included with
your hub for illustrations of these rules.
Full-duplex link to the hub. Regular hub ports, including the ports on
the HP 10/100 hubs, only operate in half-duplex mode. If the attached
device is running in full-duplex mode, it will cause a high number of late
collisions on the network, degrading performance for all nodes. The HP
10/100 hubs must not be connected to devices that are configured for full-
duplex operation.
Non-compatible Speed Configuration. For the Hub 12M and Hub 24M,
make sure that you have not configured any port to operate at a speed
that is not compatible with the attached device (10 Mbps or 100 Mbps).
Faulty or loose network cables. Look for loose or obviously faulty
connections. If they appear to be OK, try a different cable.
Troubleshooting
Basic Troubleshooting Tips
3-3