Paul Muller is a fish and coconut-milk importer in his sixties who needs to talk to his business partner in Thailand for “at least 30 minutes” every day. Where he once paid £1.06 per minute, calling from West Grinstead, Sussex, he now makes these calls entirely free of charge — and says he saves almost £10,000 a year.

“I was persuaded by my business partner, who travels all over Thailand, that the best way to speak with him was through my computer,” he said. “So I got a broadband connection and a £10 microphone, and haven’t looked back.” Setting up was simple: “I’m not very clued up about computers, but I plugged the microphone into the pink socket on my laptop — and away I went.”

Free calls by voice over internet protocol (VoIP) have been an enduring fantasy among internet evangelists, with venture capitalists milked for billions of pounds in the headlong pursuit of this telephonic nirvana. In the theatre of their minds, the nerds would slash the cost of phone calls and laugh as the mandarins at BT leapt from their toppling tower.

Until recently, however, progress was slow. The software was poor, and good-quality conversation requires broadband — something that, until last year, was rare in Britain. With high-speed access growing, a rash of voice services has been launched. Google, the well-funded powerhouse of web progress, was recently said to be set to launch a free global telephone service. If big, innovative names continue to enter a market that offers immediate savings, customers are bound to follow. VoIP finally makes sense in the UK, where about a third of internet subscribers now have broadband.

There is a palpable sense of antici- pation that viable VoIP might finally be ready to rock and roll. The research firm Evalueserve forecasts that revenues for Europe’s telephone companies could fall by as much as 10% because of the surge in demand for internet telephony, with profits sliding by 25% by 2008.

The simplest way to understand VoIP is in terms of three types of service. You can use your computer to talk to somebody on another computer, or other software to make calls from your computer to land lines or mobiles, or services that don’t require a computer at all — you simply plug a handset into a broadband connection.

All of which are not to be confused with existing services from OneTel or Carphone Warehouse, which divert traditional phone calls in a system known as carrier preselection (CPS). Instead, VoIP sends calls along the backbone of the internet, which is an innovation for consumer telephony, although business has long enjoyed the benefits.

The simplest of the IP options remains computer to computer, which Muller has chosen. All the big Instant Messenger (IM) providers — MSN, AOL and Yahoo! — have added free voice calls to their text-based chat systems. “The advantage is that these are free and generally work well,” said Ian Fogg, broadband and personal technology analyst at Jupiter Research. “Others, such as SkypeOut, will now contact the land lines of people who aren’t online at all.” The downside to these software-based systems is that you have to be at a computer, which must be switched on, and voice quality depends on the broadband connection working well.

“I don’t bother calling people in the

UK through MSN because I have a BT Option 3 call package,” Muller said. “When calling overseas by MSN, the line quality isn’t bad. You have some bad days, but you get those with an ordinary line. You need to adjust to not always having such an animated conversation. After all, it is free.”

With most IM services, you simply click on a button to initiate (or accept) voice calls; if you have a webcam, there is wobbly video on offer. Doors tried this and succeeded through MSN after some teething problems. With the Yahoo! service, we swiftly managed an adequate audio conversation, so long as we didn’t talk simultaneously. Your friends must be on the same messenger service, although Trillian software (www.ceruleanstudios.com ) can act as a go-between if you’re on MSN and your friend is on Yahoo!.

Another big name in broadband tele-phony is Skype, which last week launched a Mac version. This makes it easy to “phone” any of the 50m people who have also downloaded its free software. SkypeOut, its big brother, sells prepaid credits for calling traditional phones. Many countries are charged at one penny per minute, with others, such as India, at up to 10p. An hour-long daytime call to New Delhi, for example, would cost £9.30 less through Skype than BT.

The software is inelegant, but easy to use after a simple installation, and sound quality is adequate, if a little murkier than a standard phone line. Gossiptel is similar, with clearer call quality. Like SkypeOut, it is a boon for the business traveller, as a hotel room with net access means free or extremely cheap calls. Gossiptel is also very easy to set up.

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