What is the difference between a Hub and a Switch?
During day to day conversations about networks it is more than likely you will come across the terms "hub" and
"switch", you may well be asking what is exactly the difference; especially as a switch can look exactly the same as a hub with the
only recognisable difference being the word hub or switch being displayed on the front of the device.
A hub or a switch is the concentration point or centre of a network where all localised devices (Internet, PC's, Printers etc) connect to
in order for different users to share.
A "hub" is the older of the two in technology terms and found its way into computer networks when structured cabling or Unshielded Twisted
Pair (UTP) cabling became a cost effective option some 15 years ago. (This is more than likely the type of cable installed at your site).
A hub offers a single broadcast domain, or can be thought of as a single lane road. The more users that are active upon it the more
congested it becomes. Traffic will still pass quite happily along the road, but the speed of reaching the end location will be reduced in
line with the increase in amount of users.
A switch offers multiple broadcast domains and may be thought of as a multi lane motorway. From the point of being turned on the switch
learns what is connected to each of its ports. Then when a particular device wants to communicate, or enter the motorway, the switch knows
which port to direct it to, or which lane it needs to be on because it has travelled there before. The end result of this facility is that
the speed of travel is far greater than in the case of a Hub
In the early days of Hubs a more expensive device known as a switch was openly available, but in many cases the higher price outweighed
the benefits. These days hubs are no longer actively sold as Switches are now no more expensive than a Hub so why pay the same price for
lesser technology?
What Sort of Switch do I Need?
Switches should always be purchased now rather than Hubs.
The common requirement for a switch is to have dual speed capability connections to the desk tops or work stations, 10/100 mbps, and
either 16 or 24 ports. The number of ports is dependant on how many network data outlets the switch is linked to & whether it needs
to allow for future expansion of the network. It is recommend to allow up to 40% for future expansion.
Many network switches these days require at least one Gigabit (1000 mbps) up-link (backbone) port from a central core switch commonly used
for server connections. Some networks will require tri-speed switches such as 10/100/1000 mbps connectivity a scenario may be where you
may have newer PC's with Gigabit capable Network connections, as well as older units with 100mb. In addition to this it is not unusual for
an internet connection to operate via a 10mb port, hence the need for all three mediums in some cases.
Some switches these days come with modular slots or ports to enable fibre optic connections whether they are 100 mbps or 1000 mbps (Gigabit)
connections. A typical example of this is when connection is required to other buildings within the same campus. These may well have either
100BaseFX (100mb fibre), 1000BaseSX (Gigabit shorthaul fibre) or even 1000BaseLX (gigabit longhaul fibre). Having modular slots can enable
you to offer a variety of these connections.
There is also the question of whether to buy a manged or unmanaged switch
If in doubt contact us for further assistance.
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