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.

A collision occurring after the normal collision window of 72 bytes. Late collisions may indicate chattering transceivers, defective interface cards, defective network software or hardware, mismatched equipment, an oversized network, or other problems.

Late Collision is a type of collision found in the CSMA/CD protocol standard. If a collision error occurs after the first 512 bit times of data are transmitted by the transmitting stationIEEE http://standards.ieee.org/getieee802/802.3.html 802.3-2005 Part 1, http://ieee.org IEEE section 5.2.2.1.10, a late collision is said to have occurred. Importantly, late collisions are not re-sent by the NIC unlike collisions occurring before the first 64 octets; it is left for the upper layers of the protocol stack to determine that there was loss of data.