In a
network, when two or more stations attempt to transmit a
packet across the network at the same time, a packet
collision occurs. This is not uncommon in a shared medium such as an
Ethernet that has many computers in the same network
segment. When a packet collision occurs, the packets are either discarded or sent back to their originating stations and then retransmitted in a timed sequence to avoid further collision. Packet collisions can result in the loss of packet integrity or can impede the performance of a network. Also see
CSMA/CD.