Technical data

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Collision domain
A collision domain is a segment where connected equipment must be capable of
detecting and managing collisions (as several devices send simultaneously). Data that
collides does not disappear automatically, but CSMA/CD neatly and tidily ensures the
data is retransmitted. The number of retransmission attempts can be limited to 16,
and it is not until then that data can be lost. On the other hand, it is only usual with so
many retransmission attempts on a very heavily overloaded Ethernet network.
An Ethernet packet basically consists of 1518 bytes, if you use VLAN a further 4 bytes
are added, which in total gives 1522 bytes. This, together with the speed of the net-
work, gives the prerequisite for how quickly a message reaches the most remote
devices on the network. Under no circumstances may a collision domain be construct-
ed so that the sending device can not identify a collision before knowing in all certainty
that the packet has reached the receiver. The network and installed equipment deter-
mine the maximum propagation on a collision domain as all equipment adds a delay,
also known as latency.
Destination
address
Source
address
Type Encapsulated data
1518 bytes
A
C
t
t
t
D
B
F
E
CRC
B A C K