What is SIP Trunking

Businesses can reduce long-distance charges and connectivity charges related to the need for separate lines and connections for voice and data communication through SIP trunking. SIP trunking stands for Session Initiation Protocol trunking. With this, people in the business can communicate outside the business through IP. Traditional phone lines can even be replaced with an IP phone system connected with SIP trunking, which creates basically one pipeline within the organization to carry voice, data and even video.

Regular SIP trunking merges data and voice communication into one line. It basically acts as a merger for a traditional phone system and the Internet, allowing voice communication to travel over the data network. With SIP trunking, no functionality is lost, as people within the business can still call locally and long distance, emergency and 911 calls can still be made, and caller ID should still work normally. But because some of the voice communication travels over the Internet instead of on actual phone lines, the phone carrier can’t charge for the time the communication spends on the Internet, so the cost is less.

Setting up SIP trunking can cost a bit in the beginning, though. Three things are necessary to make it work: The business must have a PBX, preferably an IP PBX; it must have an ITSP, an Internet telephony service provider; and it must have a border element, which is usually handled by the service provider.

A PBX is a Private Branch Exchange. This is the telephone switching system within an organization that allows calls to be switched between users. An IP PBX serves the same purpose, but it switches calls between users on VoIP, or Voice over Internet Protocol, which is essential just voice communication traveling via the Internet rather than traditional phone lines.
When a business uses an IP PBX, instead of each user requiring separate lines for Internet access, telephone and VoIP communications, each user requires only one line as all these protocols share it, which makes SIP trunking efficient.

The second requirement, an ITSP or Internet telephony service providers makes sure that the IP network is connected to the traditional telephone network. The third thing, the border element is what allows the connection between the network, the phone system and the ability to use VoIP beyond the organization’s network. A firewall that allows SIP trunking, for instance, could be a border element. The ITSP should provide this element.
While an IP PBX can be an investment, as can things like IP phones and other necessary equipment for SIP trunking, it eliminates the need for special desktop equipment for each user and the need for things to switch between VoIP and the regular phone lines. SIP trunking handles these switches automatically. Telephone and long distance charges can be dramatically reduced, and because there’s technically only one connection for both voice and data instead of two, that cost can be reduced as well. SIP trunking should show any organization enough savings to pay for itself within a short period of time.