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SIP Provider

SIP lines are a new and fast-growing telephony service. It enables you to use your phone system to make calls over the internet.

BT released a statement in 2015 that it will switch-off ISDN in 2025. No new orders would be accepted from 2020.

Now is the time to switch to SIP.

Switching to SIP can save you money and isn’t as complicated as you might think.

What is SIP?

SIP trunks act like telephone lines that operate via broadband/data connections. SIP (Session Initiation Protocol) replaces ISDN connecting your business telephone system to the PSTN (Public Telephone Network).

All you need for SIP is a fast, robust internet connection.


SIP provider


SIP can save you money!

ISDN line rental is generally more expensive, and less flexible. Most calls to UK landlines are free, with significant cost savings on calls to mobiles. International calling is also less expensive.

SIP call pricing is structured with no hidden costs.


SIP is perfect for Multi-site connections

A Single phone system (PBX- private branch exchange) at your main site can route telephone calls to IP connected devices anywhere. This makes connecting multiple business locations and home workers, less complicated and saves you money.


Multi-Site SIP


SIP is scalable

If your business is seasonal, SIP can be scaled-up to manage a higher volume of calls, then scaled-down during quieter times. Businesses experiencing growth can increase capacity without waiting for an engineer’s visit. Additional users can be added at any time for the price of a new handset.


Phone Numbers on SIP

Need a one-time campaign number? 0800 or local number for another city? Multiple phone numbers to ring a single phone? Because SIP uses cloud technology and there is no physical location, SIP can manage all these requirements. Even when moving office location but need to keep your existing numbers, by porting your numbers to your SIP provider.


SIP Delivers UC (Unified Communications)

Unified communication integrates all forms of business communications across devices. The SIP protocol is capable of more than phone calls. SIP manages video, instant messaging, file sharing, and screen sharing across multiple end-points. Including handsets, mobile devices, and computers. All designed to save time, simplify activities and reduce cost.


How SIP works


Converting to SIP

Converting to SIP is straight forward, unfortunately, not all phone systems (PBX) are compatible with SIP. There are many Hybrid phone systems (PBX) that can replace your existing phone system and you can keep your existing handsets. Although in the long run it may be worth looking at a completely new system.


How many SIP trunks do I need?

You need 1 per concurrent call. If you have 6 people that all need to make calls at the same time, you will need 6 trunks. It’s unlikely that in an organisation of 100 staff that you’ll need to make 100 calls at the same time. 30 trunks should be more than enough in this case. You can increase/decrease as you need to for busy/quieter times.


SIP is secure

As with anything in life, when implemented and maintained correctly, fraud should not be an issue. A properly configured SIP channel will manage your connectivity via dedicated firewalls. Call monitoring can be set up, should the system become comprised, all calls can be automatically blocked.


SIP is dependent on bandwidth

For SIP trunking to be successful, you need a broadband connection that can support your requirements. It’s advisable to speak to an expert about your connection. They may recommend upgrading your connection to meet increased bandwidth requirements.


SIP Disaster recovery plan

Power outages, connectivity issues or storm damage can leave most businesses unable to operate. SIP trunks are managed in the cloud making your business less vulnerable to this. Cloud enables call diverts to alternative offices or alternative numbers and is quick and easy to implement. Having a disaster recovery plan pre-arranged minimises disruption. Should the worse happen, a quick phone call or email to customer support puts your pre-arranged plan into action.

Why customers switching to SIP and would it suit your business?

  • If you have a phone system that is compatible with SIP (we can advise you), you can cancel your ISDN phone lines and just have SIP lines (IP calls through the internet)
  • SIP is the perfect solution to extend the lifespan of your existing PBX system as ISDN digital phone lines are due to be switched off by BT.
  • Calls can be switched to enable you to use ISDN as well as SIP lines.
  • We have helped our customers to save an average £4,800 per annum by upgrading their phone system (PBX)with SIP lines in replacement of the ISDN circuit
  • Our specialist team are on hand at the point of installation and assist with the ongoing configuration. Our aim is to make the switch over to SIP easy and hassle free
  • Our technical team installs and provide ongoing support. No waiting on the phone for hours, we help keep your business moving forward.

Comms Connect business consultants spend quality time with you. We learn about the communications you need now and for future growth.


Tel: 0345 370 5000
or email

SIP Lines

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