Switch is a networking device which forwards frames according to its MAC Address Table. It presents a switched path to the devices which are connected on it. This is the biggest difference between a switch and hub. While two network device trying to communicate each other which is connected to a switch, other network devices can communicate each other too . That means switch can perform a great bandwith optimization according to hub. It provides dedicated bandwith for each host.
They may have 4, 8, 12, 24, or 48 ports like a hub. Managed switches can be managed remotely with telnet and SSH by their IP addresses and default-gateways or they can be managed on site via console cable. These kind of devices can work with VLANs too.Unmanaged switch is the device that you can’t attach an ip address, default-gateway or VLAN.
Some switches can carry gigabit / terabit ethernet traffic, a hub can just carry up to fast ethernet.
Some of the switches can provide power for the network devices too, that kind of devices are known as POE switches. POE supported network devices don’t need any electrical adaptor to work. They get their power from the switch. ( Like Cisco 3750 )
Switches work on Layer – 2 of the OSI Model mostly. But some devices can work on Layer – 3 too. Layer – 3 switch can make routing too.
Switches may support fiber optic cables or UTP cables. That varies due to switch’s model. Fibre optic switches are mostly used for carrying high bandwith.
NETWORK SWITCH VENDORS
Here is the list of the network switch vendors :
Avaya – acquired Nortel
Brocade – acquired Vyatta
Dell – acquired Force10
Enterasys – acquired by Extreme Networks
Ericsson – acquired Redback
HP – acquired 3Com
Meraki- acquired by Cisco Systems
Rad Data Communications