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CHAPTER 4: Indicators
4. Indicators
Before connecting network devices to the hub, take a few minutes to read this
chapter and familiarize yourself with the front-panel LED indicators.
4.1 Hub State Indicators
• Power Indicator: This indicator lights green when the Hub is receiving power;
otherwise, it is off.
• 10M Collision, 100M Collision: These indicators indicate data collisions on the
respective 10-Mbps Ethernet or 100-Mbps Fast Ethernet segments of the Hub.
Whenever a collision is detected, the respective COL indicator will briefly blink
amber. (Although several hubs can be stacked or linked together, the stacking
capability of the Hubs connects the 100-Mbps collision domain only; that is
why the stack has a capacity of 140 Mbps total bandwidth—the common
100BASE-TX domain, plus one 10BASE-T domain for
each
hub in the stack.
Therefore, a collision on a 10BASE-T segment will
not
be shown on the other
hubs in the stack, but a collision in the 100BASE-TX domain
will
show on each
hub in the stack.)
• FX Link: Reserved for future use.
4.2 Port State Indicators
Status indicators exist for each of the twisted-pair ports on the Hub. Each port’s
LED status indicators report the port is working on 10BASE-T mode or
100BASE–TX mode and indicator link or receive status.
The following describes each indicator and the meaning of each condition:
• Link/Rx: This indicator lights green when the port is connected to a 10-Mbps
Ethernet or 100-Mbps station. If the station to which the hub is connected is
powered off, or if there is a problem with the link, the LED will remain off.
The indicator blinks green when the data will be received to all other
connected ports.
• 100M: This indicator lights green when the port is connected to a 100-Mbps
station; otherwise, the LED remains off. This means the port is connected to a
10-Mbps Ethernet station.
