Late Collision
A failure of the network in which the collision indication arrives too late in the frame transmission to be automatically dealt with by the medium access control (MAC) Protocol. The defective frame may not be detected by all stations requiring that the application layer detect and retransmit the lost frame, resulting in greatly reduced throughput.

Link Integrity Test
This test verifies that an Ethernet link is connected correctly and that signals are being received correctly. This is a helpful aid but does not guarantee the link is completely functional.

Link Layer
Short for Data Link Layer. This is layer 2 on the OSI model.

Link Pulse
A test pulse sent between transceivers on a 10BASE-T link segment during periods of no traffic, to test the signal integrity of the link.

Link Segment
A point-to-point segment that connects only two devices and is "capable" of supporting full-duplex operation.