If ever you need proof that Voice over IP (VoIP) has finally arrived, pop down to your local Tesco where you'll find a VoIP-enabled handset and calling plan package retailing for less than £20.

The move by the UK's largest supermarket group illustrates two things. First, VoIP has developed to such a degree that relatively non-technical consumers can be offered it at the same time as they buy their weekly groceries; and second, the underlying technology is now robust enough to support such a widespread rollout.

Calls from the Tesco internet phones are priced at 2p a minute to anywhere in the UK, the US, Canada or Australia. It is a clear and aggressive attack on the more traditional fixed line, circuit-switched services.

At the time of the launch Andy Dewhurst, chief executive of Tesco Telecoms, said: "The way we communicate is rapidly changing and we believe that this is just the beginning of the internet phone revolution. Our research showed that, while many people are aware of internet phone services, most have been put off by complicated technology and confusing tariffs and installation."

Indeed, buying a VoIP handset from Tesco is a world away from the VoIP solutions of the past. Technology such as Skype, for all its ingenuity and success, was never likely to achieve world dominance because it was something of a techy's toy.

The explosion of Skype was largely by word of mouth. Those in the know could benefit from extremely cheap, if not free, calls through their internet-connected computers.

Invented by a Swedish internet entrepreneur and his Danish partner, Skype boasted millions of users around the world before it was sold to eBay late last year in a deal that could ultimately be worth $4.2bn by 2008.

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