Intruder Prevention; Eavesdrop Detection - HP 10Base-T Hub 24M Manual

Take a moment to review the settings in the Port Security environment.
Additionally, you may want to become comfortable with several concepts
before continuing. Network security comprises several features that are
commonly used for protecting your device from potential problems.
The features used are described below.

Intruder Prevention

A feature that stops an unauthorized computer from gaining access to the
network. The manner in which this action occurs is through the address
selection method, a technique that sets addresses for which the port is allowed
to connect. The three address selection methods are:
First Heard
Continuous
Assigned
See the section, "About Address Selection Methods" to learn about each
method. When a port is configured for Intruder Prevention, the hub examines
the source address of each packet coming through the port and compares it
with the address permitted by the address selection method. If the addresses
are not the same, the hub concludes that an intruder, or unauthorized device
is attempting to gain access to the network and takes the appropriate action.
Actions can be either sending an alarm to a log, disabling the port or both.

Eavesdrop Detection

A feature that stops a device connected to a port on the hub from seeing
network packets not intended for that device. The hub performs this task by
comparing the port's authorized address with the destination address of
packets being repeated through the hub. If the addresses do not match, the
packet's bit pattern is scrambled, rendering it unreadable by any device on
that port.
Configuration Reference
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