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    November 13, 2019

    Your SIP Trunking FAQ Sheet

    You may have been hearing a lot about VoIP, UCaaS, internet telephony, and the wonders of SIP trunking. While there is an abundant amount of information coming out about VoIP and UCaaS, here’s your chance to comprehend SIP Trunking a little better, as we cover some frequently asked questions.

    What is SIP?

    SIP, or Session Initiation Protocol is a method of data transmission used to set up connections between different devices including computers, desktop phones, mobile phones, video conferencing units, and file servers. It governs the establishment, termination, and time during phone calls as unique sessions.

    What’s SIP Trunking?

    A SIP trunk is a virtual telephone line connecting your business telecoms system to the public phone network. Rather than using an ISDN connection, SIP trunking is established via a data network. SIP trunks may be used as a complete alternative to ISDN, or the two systems may be combined to give a hybrid solution exploiting the benefits of both.

    What are the advantages of SIP Trunking over ISDN?

    ISDN lines typically come with monthly charges for line rentals. But SIP trunks use your existing data connection (Local Area Network or LAN, internet access subscription, etc.), and incur no additional fees. On top of that, communications made over the internet (including long-distance and international calls, which may be charged at local call rates) are much cheaper than those made over traditional phone lines. Businesses typically enjoy monthly savings of at least 50% over their previous tariffs.

    As SIP trunks are managed over a data network, it’s quick and easy to use your existing connection to add or remove channels – without the need to install additional circuitry.

    When should businesses switch to SIP?

    If you are thinking of moving to the cloud to enjoy all of the benefits of a hosted solution, but already possess an on premises PBX system, then a move to SIP trunking should be an easy transition for you. If you currently use ISDN2 or ISDN30 circuits, and have a leased-line or dedicated SDSL for your internet connections (as opposed to contended ADSL or WiFi), then SIP trunking should be a good fit for your organization.

    What equipment will I need?

    If you’re using a legacy phone system (and these days, that equates to a couple of years old, or more), you’ll likely need a SIP-ISDN Gateway, which translates the flow of data between the ISDN interface of your existing phone system and your new SIP trunks.

    Rather than trusting to the bandwidth of the public internet, it’s a good idea to beef up your existing data connection to allow for the increased demand that will be put on it by voice data.

    How many SIP trunks should I get?

    This will be determined by the maximum number of simultaneous phone calls that you anticipate at any given time. Many organizations are just fine with one SIP trunk for every three phones, but if you’re running a call center, or your business handles a large volume of inbound and outbound calls, this will require considerably more – sometimes as much as one SIP trunk per phone line.

    Will it cost me a bundle?

    It certainly shouldn’t. You may need to shell out for a SIP-ISDN Gateway, and you’ll make an upfront payment to your SIP trunk provider to establish a connection. Beyond this, the call and operational charges should actually save you money.


    To learn more about how a SIP Trunking solution can benefit your organization, reach out to the experts at net2phone today!



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