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We are not going to attempt a detailed explanation of what SIP or VoIP is on this page as we know you probably don't have time and you might not really care about the technicalities! If you want more detail please download our brochure below.

Download our SIP brochure here

It is suffice to say that SIP and VoIP are now prevalent in the solutions we are delivering to most customers today.

SIP Trunks (voice lines delivered on an internet connection) are now a viable or even preferable alternative to ISDN as your main voice connection into your premises.

The reason....?

It's simple – SIP Trunks are more flexible and feature-rich and can also be cheaper. Also, with better internet connectivity now in the UK, they can be delivered reliably (by us anyway – we cannot speak for others!).

VoIP (Voice over IP) is basically voice delivered on a data network – this could mean your internet connection (in the case of SIP trunks) or on your computer network (in the case of an IP phone or SIP endpoint like a smartphone or windows soft phone.

However SIP and VoIP is not right for everyone – we suggest you ask us for advice. It may be that ISDN and traditional digital phones are better for you.


Ask us to appraise this for your particular situation. Here are the benefits of OUR PARTICULAR SIP trunk offering when compared to ISDN:

  • SIP trunk rental is normally cheaper than ISDN line rental
  • Calls to UK landlines and UK mobiles are free (subject to change)
  • SIP can be delivered on the same internet connection that you use for internet/email (we normally recommend a proper converged solution where we prioritise the SIP to ensure good call quality – putting SIP on a connection without such priority may result in poor performance)
  • SIP trunk capacity can be increased or reduced instantly (subject to contract) without a long lead time or engineer visit (unlike ISDN)
  • You can receive calls or send out calls with any number (ie no geographical limitations governed by your local BT exchange area like ISDN)
  • You can re-point or relocate your phone service quickly and easily – great for Business Continuity or disaster recovery. See the video below.
  • There are normally no extra peripheral charges for Direct dial, caller ID etc (unlike ISDN)

Note, as well as SIP trunks (lines delivered on an internet connection), there are also SIP extensions or devices. These are simply IP devices that use the 'open' SIP Protocol to communicate (rather than some vendor proprietary protocol). Note that using SIP extensions is OK but there are huge security issues that demand consideration – please call us for advice on this as ignoring it could cost you thousands!

Watch the video below and discover more about Gamma Fraud Management.. 

See here the Gamma video explaining an important feature of our SIP trunks that allow your business to function and receive calls when you lose local connections.

As you can see, we have extensive real life experience of SIP and have dealt with a lot of SIP solutions over the last few years – please call us for advice on 01892 676000 – ask for Paul, Michael or Nick.

What our customers say...

"Brilliantly efficient, Andy the engineer could not have been more helpful!"
Kathryn Redington - Columbus - 5 Star Facebook Rating

Our Partners include:

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