SIP Soft Switch 101

Many people who wish to know about Session Initiation Protocol (SIP) and its basic elements always fall; short on the account of getting to know the SIP softswitch. So let us take a good look at this very elusive member of the entire SIP system.

For quick background information, SIP is the technology that allows telephone systems to be able to function over the internet. Meaning, instead of traveling through the traditional phone lines that we know, SIP systems sends off their call signals through the World Wide Web. So, within this entire process, where does the SIP softswitch lie?

First of all, in order for a telephone system to be connected to the internet and vice versa, they are interconnect through a softswitch. The softswitch is the main device that captures and controls all the signals created by the entire system, particularly the signals for phone calls made and received.

What happens is that the softswitch analyzes the signals that passes through it and then routes the signal to where it is intended to go. But not only that, as it also adjusts the properties of these signals.

For example, a PSTN (Public Switched Telephone Network) number connects a call to a SIP enabled system.

The softswitch will then convert the PSTN signal to be in IP-form so it can be accepted by the SIP telephone system. And this is also what happens if the SIP system calls a normal PSTN number.

Because of its functionality, the SIP softswitch is a particular favorite among many SIP system users because it has the capacity to eliminate long distance charges from long distance phone calls.

Hence, it is the main reason behind the cost efficient property of all SIP telephone systems. So now, do you understand exactly what a SIP softswitch is and how it functions?