Tuesday, April 28, 2015

Basics of Switching | Switches- part 2

Basics of Switching

Switching is a basic function of networking. Switching breaks up large collision domains in to smaller ones.

A Switch or a LAN switch is a hardware device little advanced than the traditional Hubs used for broadcasting based on software.

  • A switch can be a multi-port Bridge.
  • Switch have the forwarding decision same as the bridge and have simultaneous data transfer.
  • It establishes connection using the MAC addresses of the devices.

Many OEMS (original equipment manufacturer) now are in market with their advanced switches. A switch have many ports for connecting the cables. It comes in different numbers such as 8, 12, 24, 48 etc.


A typical Cisco Switch device


When it comes of switching in networking, it describes in two ways : 

Circuit Switching & Packet Switching

It is used to move traffic from one part of network to another. Data received from the input port need to be transmitted to one or more output port .

Just understand with some visuals :







According to the Application layers, switches are also used in 1-7 layers. There are three main functions of layer-2 switching as below:
  • Address Learning
  • Forward/filter decisions
  • Loop Avoidance
There are different types of switches available. User have to choose as per their requirement. Below mentioned are the types;
  • Modular Switch
  • Fixed-Configuration Switch
  • Un-managed Switch
  • Managed Switch
  • Smart Switch
  • Stackable Switch
  • PoE switch
  • Virtual Switch
While choosing switch also you need to check the number of ports available, speed of the switch (10/100 Mbps, 10/100/1000 Mbps etc.), PoE (Power over Ethernet or non PoE), Stackable or standalone. 

Now a days switches come with ports such as 10, 16, 24, 28, 48 and 52.


-DR





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