Why More and More Businesses are Making the Move from ISDN to SIP Trunking.

27 February 2015

Session Initiation Protocol (SIP) is a suite of technologies that connects your phone system to the Public Telephone Network.  Like ISDN, SIP connects your phone system to the outside world, but they do this in a radically different way vis-a-vis a standard internet connection that makes use of a SIP trunk. SIP trunks are designed specifically to carry voice data over a broadband or managed internet connection and so are of very high quality. It is the SIP provider that actually connects to the Public Telephone Network (PSTN) and routes calls and data to and from your premises.

Although SIP was developed in the 1990’s, it was only used as an active technology since about 2007. It is now rapidly gaining prominence as a business telephony technology, mainly due to the increased number of features and benefits that it offers over ISDN. As we will explore later, flexibility, scalability, value for money, business resilience, and multi-site connection are at the heart of why SIP is becoming so popular with so many businesses.

Business Uptake

SIP is a growing technology, tipped to exceed a market size of $8 billion in the US by 2018, and making big gains in the UK, too. A study by Illume research showed that the market added 129,791 SIP trunks in the first half of 2013, a growth rate 17.1%. 

 “There is no denying the world is moving to IP, and SIP has become the de facto solution of choice for businesses for IP connections. In North America, slightly more than 20% of the installed business trunks are SIP trunking today, with significant upside opportunity,” says Diane Myers, principal analyst for VoIP, UC, and IMS at Infonetics Research.

Business advantages

Many of the advantages of SIP stem from the fact that it runs over standard internet lines. ISDN requires a specific type of connection to your building, while SIP will run over any business grade internet connection. As a consequence of this;

  • SIP is scalable

It can be scaled up or down as your business needs dictate. SIP trunks can be added or removed with no interruption to your business. Seasonal demand in incoming and outgoing calls are easily managed.

  • SIP is flexible

Telephone numbers, both geographical and non-geographical, can be routed to whatever endpoint you require. This makes keeping your numbers when moving office much easier.

  • SIP is cost effective

By leveraging standard business technologies and being easy to manage, SIP can reduce your overall telephony costs.

  • SIP is resilient

Because it is a re-routable technology, SIP can withstand sudden changes of location. Disaster recovery and business continuity plan can be greatly enhanced with the addition of SIP to your business

  • SIP can work with multiple sites

SIP trunking means that you can better control the number of PBX’s at each site you maintain. Distribution and management of calls and numbers is made easier and quicker with SIP.

  • SIP is a safe technology

Because of the way SIP works, additional security measures must be taken. A correctly setup SIP line does not pose a security risk to your business. SIP is also an active technology, which means that constant development is underway to ensure excellent call quality, security, and a strong feature set remain at the forefront of this versatile technology.

If you think your business could benefit from the flexibility and cost savings SIP can bring then please give us a call.

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