Using Voice over IP to control your phones

Back to basics
VoIP hasn’t taken off to the extent that many would have imagined, at least in the home. In the business world, it’s a different matter, and many companies use VoIP to route calls cheaply, either instead of traditional phone lines, or in addition to them; in fact, many of the cheap calling card or alternative carrier services available are VoIP-based, so when you dial into them, you’re routing your call onto a VoIP network, and saving money, without having to set up equipment at home.

In many cases, the calls aren’t going over the public internet, but over a dedicated link that uses the same protocols, which helps ensure quality. Send a VoIP call over a connection (such as your home broadband) that’s also being used heavily for something else, and quality can suffer.

While VoIP is largely used by business at the moment, there’s one service that’s broken into the mainstream rather more successfully – Skype. Part of its success is due to the ease of configuration, with no need to type in complicated server addresses, and being able to call people just by using a nickname.

Rather than using the same open standards – known as Session Initiation Protocol (Sip) – as most internet telephony systems, Skype uses its own peer-to-peer technology.

Originally reliant on PC software, there are now an increasing number of standalone handsets that you can just plug into your network and use like other VoIP phones.

While the Session Initiation Protocol (Sip) leads the way for professional VoIP, many home and small-business users, opt for Skype. It’s easy to set up and there’s a good range of equipment. But if you want a more complete phone system, things aren’t as straightforward.

That doesn’t mean setting up a system like those described above. Most software PBX systems, including 3CX and Asterisk, can be configured with software-based Skype gateways, so you can route calls to Skype, and receive them ­ setting up rules to determine which extension will ring for an incoming Skype call, or short numbers that can be dialled on any phone and map to Skype user IDs.

There’s even a free service called Opensky from Gizmo5 which you can use to make calls to Skype users from any Sip phone, including the built-in Sip software on Nokia mobiles.

Getting started
If you’re experimenting with VoIP – and it’s as well to get the basics working before you try and persuade the rest of the family to try and change the way they use the phone – you probably don’t want to spend a huge amount of money and fortunately you don’t have to.

There’s a wealth of free Sip softphone programs available, including X-Lite from Counterpath. But you may have something even more useful – a proper phone. If your mobile phone supports Wifi, there’s a good chance you’ll be able to use it to make Sip calls, either with a third-party program such as Fring, or by using the built-in Sip software, which is found on some Nokia N and E series handsets – see later for an explanation of how to configure a Nokia N85 to make internet calls.

In fact, if you do have a mobile phone that can be used to make internet calls, you’re well on the way to ‘convergence’, where you can just use one device for all your calls.

With many of us keeping all our phone numbers stored in the mobile, it makes sense to use that as a handset at home, too, where a well set-up VoIP system can help ensure you make calls as cheaply as possible.

As well as phones – whether hardware or software – there are some other things you’ll need. First is a Sip provider and the second, for more advanced users, is software to turn a PC into a complete phone system.

A Sip provider is a company that operates servers to which internet phones can connect, and provides services such as voicemail and connections to the rest of the world. Those connections can be via VoIP links to other providers, allowing you to call them free, or to the telephone network (often referred to as the PSTN, or Public Switched Telephone Network). The PSTN connections allow you to make calls to ordinary phones, and provide a way for people using them to call you.