Microsoft chairman Bill Gates believes the computer industry will outgrow spam, and predicts that Wi-Fi will be a key technology both for homes and business.

Speaking at ITU Telecom World 2003, Gates said that Wi-Fi had taken off in the four years since the last event, and that it would find its way quickly into the enterprise and be key to developing the digital home.

"Wi-Fi in the enterprise is on the way to becoming a common sense tool to drive business productivity," he said.

In residential areas Wi-Fi could drive "the dream" of the digital home, he added.

But security is still a major issue for Microsoft. Gates acknowledged that the "level of richness and maturity" needed to secure the wired and wireless digital world has yet to appear.

Gates said much of Microsoft's $6.8bn (£4.1bn) investment in research and development was being focused on this area, and suggested radical changes in the way society approaches internet technologies.

He called on anonymity to be removed from internet protocols like SMTP, because it allows spammers to mimic other users, and suggested that passwords could be replaced by smart cards and biometric technologies.

"We have to know who is accessing the network. By being able to identify who the sender is we will be able to make the spam problem essentially go away," he said.

Gates added that by the end of the decade the majority of homes in most developed countries will be connected to the internet by broadband.As Wi-Fi had been a surprise in the last four years, the service opportunities offered by broadband would "surprise us all", he said.

One such service, IP-TV, would be offered by all major broadband operators this decade. IP-TV would offer a much richer user interface than TV "as we historically know it", he added.