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SIP Trunks & VoIP

What is SIP Trunking?

Advantages of SIP...

SIP Trunks & VoIP

Fast. Simple.

The telecoms industry has many 3 letter acronyms, such as SIP. SIP stands for Session Initiation Protocol. This jargon can be complicated, but in reality, SIP is a very simple premise. Most businesses have 2 separate connections:


Telephone line - To make calls using the office handsets (These lines are analogue or ISDN)

Internet - To connect to the world wide web with computers and smartphones (These lines are Ethernet or fibre)


A business pays for these 2 separate services individually, which can be expensive. By having SIP Trunks, these 2 lines are rolled into 1. One line, one bill. This can reduce costs because it means that a business can reduce two  costs into one.

As a guide, we say that if your business makes five or more simultaneous calls on a regular basis, then a Fibre To The Cabinet (FTTC) or Fibre To The Premises (FTTP) broadband connection is required. Fibre broadband has a much higher speed than regular copper lines. Commsplus RECOMMEND that, if your business has a download speed of less than 40Mbps and an upload speed of less than 10Mpbs, you stick to regular telephone lines (ISDN) for making and receiving calls. However, each connection is different and therefore, if you believe that your connection is able to handle your calls, please get in touch with us!


The only problem with SIP is that it requires a fast broadband connection with a lot of bandwidth. Many businesses based in rural areas who suffer from slow internet may not be liable for SIP trunks.

During peak times, SIP Trunks are prioritised over data, meaning that calls will still pass through, even if the internet connection slows.


Another benefit to SIP is that it is able to run on the same handsets - meaning there is no cost to of buying brand new handsets.*


Not only this, but the voice calls will be the same quality as a regular analogue or ISDN telephone line.


SIP Trunks can be provisioned at a much quicker time scale than waiting for an Openreach appointment.


Channels can be increased or decreased quickly when needed.


Number porting is available to retain your existing recognised telephone numbers.


New numbers can be provided quickly and aren’t location restricted, giving you a national or international presence.


*SIP compatible handsets required

The way SIP Trunks work is by using your internet connection (Ethernet or fibre) to make and receive voice calls. It does this by running over your existing internet connecting and freeing up room for voice calls.


A SIP trunk is a very flexible alternative to traditional analogue or ISDN lines, used as a method for connecting to the Public Switched Telephone Network (BT) to make calls to land lines, mobiles or international destinations. There is no need for additional dedicated lines, SIP Trunks can make better use of your existing broadband or data connection.

It's elementary...

It's pretty astonishing...

SIP Trunks & VoIP not for you?

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© Copyright Commsplus Limited. 2018

Designed by James Whitrow

All information correct at time of publication

All calls are recorded for training and quality purposes


Commsplus Limited registered company number: 2239626

Registered office: 51 Gazelle Road, Weston-super-Mare, Somerset, United Kingdom, BS24 9ES