Hubs, Switches, and Collision Domains
A collision now occurs when a device or LAN-segment
receives two or more signals simultaneously.
Obviously our goal is to reduce collisions by either resolving them quickly,
or reducing the likelihood of them occuring at all.
The following diagram highlights the difference between a hub and a
switch, when node F is transmitting to node C.
The hub will retransmit the frame to all of its outgoing ports,
whereas the switch will more 'intelligently' retransmit the signal to the
ports known to be wanting the frame:
A collision domain is the set of devices (potentially) receiving a
frame collision.
Today, it is very difficult to purchase a hub,
as switches have become so inexpensive,
but hubs can still play a role in Ethernet traffic monitoring.
CITS3002 Computer Networks, Lecture 4, Local Area Networks (LANs and WLANs), p16, 20th March 2024.
|
CITS3002
