You work as the network administrator at Certkiller .com. You have installed an Ethernet NIC on a
new computer and connected it to the network. However, the amber light on the NIC is flashing
furiously. What is the problem?

A.
Data transmission is taking place.

B.
Transmission collisions are occurring.

C.
The network cable is faulty.

D.
The network is down.

Explanation:
The amber light, which is the collision light, indicates that an Ethernet collision has occurred. This
light will flash continually because collisions are common on Ethernet networks.
Incorrect Answers:
A: The green light on a NIC or hub is the link light and indicates that the NIC and hub are making a
logical Data Link layer connection.
C: If there is a problem between the NIC and the hub, the green link light on the NIC and the hub
would be off.

D: The lights on a NIC or hub do not indicate if a network is down. They only indicate connectivity
or transmissions collisions on a particular link.References:David Groth and Toby Skandier,
Network+ Study Guide (4th Edition), Sybex, Alameda CA, 2005, pp. 430-431.