Techknowledge Open Systems

Legacy Phone System With SIP Trunking

Let’s first look at how a SIP trunk functions. Assume you are calling a landline telephone number. The number you dial will be connected to a Private Branch Exchange (PBX). A PBX was a common feature in businesses. The PBX system usually has multiple outside lines that users can use to make outside calls. In addition, it connects phones within the company to one another and outdoor bars.
The traditional phone line is notified when a call passes through the PBX. An ISDN (Integrated Services Digital Network), or a copper analog, is the line used to transport the call. An ISDN line allows you to carry multiple channels at once. It may be capable of handling 30 calls at once, internal or external. Your ISDN line may be able to take your growing call volume. Because of how much money you’ve invested in the system, you may not be in a hurry to get it out.
SIP trunks can be added to your internet connection. They will transmit your calls and data over the internet rather than a traditional telephone line. SIP trunks can be used as extensions to your PBX if you have SIP trunking. SIP trunk would first take your call to the service provider, and then the call would be transferred to the person calling.

Features Of SIP Trunking
It is called SIP trunking and not SIP lines.
Trunks are more feature-rich than lines and work differently. One phone number is all that is required for plain old telephone service (POTS lines). Each cable is connected to a pair of wires provided by the phone company. If your phone number is 654-1234 and someone calls it, the call goes through the public switched phone network (PSTN) to your local central office. Calls go through a pair of copper wires that run to your home and phone system. The phone system is programmed to forward all calls from that line to a specific destination.
Let’s suppose a new manager requires her number. With the number 654-1256, you have an additional line. This is simply an extra pair of wires for your phone system. You will need two cables to connect POTS lines—one team for each line or number. Four separate lines are required if you want to allow four people or four departments to share a private number. You have occupied four cable pairs or eight wires connecting the phone company to your home. These wires are expensive to install and maintain. SIP trunking is often less costly than traditional phone services.
Let’s now look at the same scenario with SIP trunks. SIP trunks are more than just lines. They also operate in a completely different way. SIP trunks use Direct Inward Dial (DID) numbers. DID numbers don’t require a pair of wires from each phone company and aren’t line-dependent. Instead, they are sent with signaling information to let your phone know which number was dialed. Let’s take, for example, a call from a private number to your company using SIP trunks. They dial 555-1256. The ring is routed through your ITSP to your phone system and sent via the internet. You can have all four numbers routed through the same SIP trunk. There is no need to purchase a line for every number you wish to use.
Let’s now look at another thing we can do using SIP trunks. Suppose your main office is in Jacksonville, but you wish to establish a presence in other areas. You might have staff who work in the area, but you would like all calls to be routed to the Jacksonville office. A DID number would be required for calls from the Jacksonville area. These calls will be sent via the internet to your ITSP (Internet Telephony Service Provider). Jacksonville will be displayed on the phone system whenever someone calls this number.
SIP trunking allows you to assign different phone numbers. Let’s take, for example, a Gainesville number that your company has. Your ITSP will route any call to Gainesville to your phone system. Your phone system routes the call to the appropriate phones and displays Gainesville on your LCD. This will allow you to let your employees know exactly where it is coming from and how to deal with it. You can also assign numbers to different states to have an Atlanta number that is sent to your condition just as if you were there. A number can also be set from another country. For example, if your company has business in the Caribbean, you could have someone call your company using a national or local number. The call will be routed according to your instructions.
Find out how SIP trunking can be used to increase the value of your legacy phone system.