HP AdvanceStack Switching Hubs Reference Guide (J3200A, J3202A, J3204A, J3210A, and J3212A) 1996-08

1-10
Switching Hub Features
How the Hub Works
Switching Hub Features
Link Beat
Type 10Base-T devices use a signal called link beat (also called link test pulse).
This signal informs the hub of the presence of a device connected to it over
twisted-pair cable and of the integrity of the twisted-pair link between them.
The hub will not transmit packets out of twisted-pair ports that do not sense
the link beat signal. Link beat is reflected in the port LEDs; the LED will be on:
Link beat status shown in Port LEDs