user13579: How do I make an electrical switch using Arduino, that when it receives signal (wirelessly or through a LAN port) to switch off it disconnects the switch and then again told to turn on turns the switch on? 
The main problem I am facing is that I need to give a 5V output to turn off the transmission between two wires having voltage rating of 230V.

user13579: As pointed out in the comments, I would need to use something known as a relay with my Arduino.

user13614: You need to use Relays.  There all kind of relays.
Regular and Solid state ... for controlling a Regular Relay using Arduino you will need a transistor (so you will able to provide the right current to the relay to close a circle)
There are a lot of guides for Arduino and Relays (for example)

13579: <p>How do I make an electrical switch using Arduino, that when it receives signal (wirelessly or through a LAN port) to switch off it disconnects the switch and then again told to turn on turns the switch on? </p>

<p>The main problem I am facing is that I need to give a 5V output to turn off the transmission between two wires having voltage rating of 230V.</p>
 13579: <p>As pointed out in the comments, I would need to use something known as a relay with my Arduino.</p>
 13614: <p>You need to use <a href="https://en.wikipedia.org/wiki/Relay" rel="nofollow">Relays</a>.  There all kind of relays.</p>

<p>Regular and Solid state ... for controlling a Regular Relay using Arduino you will need a transistor (so you will able to provide the right current to the relay to close a circle)</p>

<p>There are a lot of guides for Arduino and Relays (for <a href="http://www.instructables.com/id/Arduino-Controlled-Relay-Box/" rel="nofollow">example</a>)</p>
