Mobile and laptop
Mobile phone and laptop internet calling

What is SIP?
What is meant by SIP Calling?

SIP is the abbreviation for Session Initiation Protocol which is simply the way that almost all information – text messages voice data video and other data – is transmitted from one device – like a smartphone or laptop – to another over the Internet.

For a more detailed explanation, we recommend this article but for most purposes it is only necessary to know that SIP is how everyday Instant Messaging, Video Calls and Phonecalls work via the Internet

Lap Top Operator
Using a laptop to make Internet calls

What does VOIP mean? How does VOIP work?

VOIP stands for Voice Over Internet Protocol and as the name implies,is a broad term which can be used to refer to any phone call made over the internet.

VoIP is an umbrella term for all of the technologies involved in transporting voice information using Internet Protocol.

VoIP relies on data connectivity to transmit voice packets, instead of the public switched telephone network (PSTN). so that Voice calls can be successfully made and received over the Internet – just like a normal two way telephone call.

VoIP lets you access telephone services over the internet. Calls are no longer dependent on old traditional phone lines.

Laptop and Coffee
Using a Laptop for VOIP calls

VOIP and SIP together? Calling Accounts?

By combining the two protocols, VOIP and SIP, the result is Unified Communications or UCaaS

This is how multimedia products such as Voice calls, Unified Messaging, Video Calls, Conference Calls, Call Recording, Voice Mail and a number of other 21st Century Comms features can all come together in one product.

Calling Accounts use VOIP and SIP together to provide a modern telecoms product. The website at https://callingaccounts.com has more information

Grandstream ip Phone
ip Handset from grandstream

What is a SIP Phone? What is an ip Phone?
What is a Softphone? What is a SIP Account?

SIP phones – or ip Phones – are generally  hardware – meaning the item is a handset, which can be purchased, and it looks like an ordinary phone. Examples of SIP phones are covered in this article and we feature a recommended phone on our “what equipment” page 

A softphone is  not hardware – it is a software based application, and can be downloaded to a device such as a smartphone or desktop computer. Sometimes known as diallers these softphones are often free applications available from on-line stores like Google Playstore and Apple iTunes

Once purchased, the SIP Phone or softphone will need to be “configured” or registered to a provider of telecom services: this may be the Internet Service Provider – providing the broadband internet available in the home or office – or another telecoms service provider like just-VOIP

A SIP Account provides the necessary access information (configuration or “log-in” details) necessary to start using the service to make calls or to use the features provided. This normally requires a payment in advance (prepayment) which is used as an advance against the cost of voice calls made through the Account

Calling Accounts are similar to SIP Accounts except that they offer much more to the user in the way of features.

Grandstream Handytone ATA
2 Port Handytone ATA

What is a VOIP Phone? What is an ATA?
What is a VOIP Account?


A VOIP Phone provides voice calls over the internet and can be Hardware – a physical handset – or Software based

We recommend this article as a simple guide to endusers thinking about switching to VOIP from home or office.

VOIP phone systems have been popular for many years – particularly in the business or office sector – because calls made within a large office from one employee to another – as long as calls remain on the local network – are FREE, which is perfect for office use as a PBX (exchange). 



An ATA (Analogue Telephone Adaptor) connects any standard telephone handset to the internet, and is directly connected to the internet through the local router. Here is a link to a useful article about ATAs and we have one recommended ATA on our features page here

A VOIP Account  is similar to a SIP account, and provides the necessary access information (configuration or “log-in” details) needed to start using the service to make Voice calls. This normally requires a payment in advance (prepayment) which is used as an advance against the cost of voice calls made through the Account.

Calling Accounts combine the virtues of both SIP and VOIP Accounts but with many more features. They can be accessed by any form of ip Phone or ATA, but most customers now use smartphones and download the free Calling Account apps available through Google Playstore and Apple iTunes.