SIP trunking: What Is It?

SIP trunking, which stands for Session Initiation Protocol, is a connection that delivers voice and media telecommunications through the internet. In other words, SIP trunking is an IP communication system using IP devices. So if you have a VoIP phone system that supports SIP, you can make use of SIP trunking services.

Through this technology, a phone call can be directed through your existing VoIP phone system using signaling information. Signals are key for your VoIP system to know exactly where to send the messages. All you need for this process to play out is an SIP supported VoIP phone and a stable internet connection.

SIP can be understood better once you comprehend how a VoIP phone connection works. As opposed to traditional landline networks, VoIP gets phone service through the Internet instead of a local telephone company. When you send a voice message, the analog signals are converted into digital signals that get transferred over the Internet. The trunking process is a little bit more detailed but we’ll try to explain it as simply as possible.

How does SIP trunking work?

Communication through SIP is possible via IP data packets through an IP signaling network. In this type of communication, there are two main types of packets. One is a signaling packet that sets up a call session. The other is called a media packet which, as the name suggests, delivers media information. Through the media packet, you can deliver audio and video messages.

Let’s take an example. Suppose you say hello into the microphone of your IP device. The IP system will convert this voice signal into analogue signals. Analogues are also understood as the binary digit combination of ones and zeros in computer language. So this data is then put into media packets and sent out using the IP network. This process is known as encoding.

At the receiver’s end, the analogue signals are decoded and reconstructed into voice signals. Now your friend can hear you say hello through their speakers.

A similar process is used when sharing video messages. Images from the camera are encoded using binary digits and sent over the IP network through media packets. The data is then decoded and the original image is reconstructed for the receiver to see.

But this is just one part of the communication signal. So you can imagine the staggering numbers of media packets passing through an IP network for a conversation to flow in real time.

To enable this communication process we need two important things. One is the user’s IP address and the other is the use of the same codec i.e. a device used to decode or encode digital data. This is where SIP comes in. SIP is essentially a protocol for communication between two or more parties. It can be considered as a rule book that helps locate the users’ IP addresses, decides which codec to use for signaling and manages the entire communication.

There are several advantages of using SIP trunking in your business. Not only do you save up on communication costs but the technology offers great flexibility for growing businesses. For more information on SIP supported VoIP systems and other related services, you can visit our website.