The internet is 35 years old.
Some believe the internet could fall following a terrorist attack
In 1969 it was a private collection of a handful of computers tended by a similar number of scientists; today we are approaching a billion users.
In the early days the internet was restricted to the technology universities, the places where the big computers lived.
Then the PC happened and by the mid 1980s the internet was growing fast.
But the web was key to the success we see today. It was Tim Berners-Lee's brainchild - putting pictures on the internet and creating the World Wide Web - that turned a technical tool into a people's playground.
The sheer number of users brought with it new technical problems.
Additionally, both the internet and the web gave a platform to the darker side of cultures all over the world, threatening to make online a no-go area.
Porn, paedophiles, race hate, spam and scams are all flooding the online world.
It now seems we are now paying the price for our earlier online freedom.
Some say that the internet is already near meltdown under the strain of government interference and the proliferation of malware.
Others, like Intel, say that it is technically obsolete.
And yet more insist that it will fall following a terrorist attack.
But they are all saying one thing: that the internet's future is less than secure, and disaster is in the offing.
Long-time internet watcher Rupert Goodwins discussed with Click Online the complicated question of whether the internet is safe.
In his opinion, "the internet's always failing, at the edges, in various places, and it's always safe.
"As things go wrong, people find ways to patch the bits that aren't working properly. They add new bits in and take out the old stuff.
"You don't even know it's happening - it's constantly being re-invented every day.
"Marc Andreessen, the guy behind Netscape, liked to tell a tale about Tim Berners-Lee, complaining to him bitterly that by introducing pictures through his mosaic web browser he was going to make the internet fall over - because there was no way the network was going to cope with all those big images.
"But as we know, that didn't happen.
"We now have streamed video, streamed audio and immense amounts of e-mail floating around. And it's still going."
Goodwins says that while there are many reasons cited why the internet might fail, they are all very unlikely.
"The internet is very robust, very distributed. If something goes wrong, you can always route round it or add a bit in.
"For example, there are lots of fibre networks which cost a lot to put in the ground but are there now. You can incrementally make those faster by adding bits at the end, and get more and more bandwidth out of what's there already.
"Like broadband - once upon a time, telephone lines gave us 2,400 bits per second access. People thought that was as fast as it could go, but now we can get eight megabits down the same lines with a bit of extra technology.
"That didn't require a huge infrastructure change, just a different box."
The reason the big players are making predictions about the internet failing is to cover themselves if things go wrong, Goodwins says.
"It is also an excuse to get money to make more investments."
"And there are people who have genuine concerns. They've done the maths, seen the way the graphs rise and say at this point we're going to run out of steam.
"Every time it has happened in the past, something's changed the rules so that that graph no longer applies.
"It's like the chip getting smaller and smaller, and faster and faster. People can say with some confidence: 'We don't know exactly how we're going to get there from here, but we know we can.'"
Goodwins says it is a bit more than just trying to increase the R&D budget - but that is certainly a part of it.
"Cyber terrorism is one of those terms that people like to bandy about but nobody can point to.
"We know that online bookings have been exploited by other groups taking down internet servers by denial of service attacks.
"But terrorism as such isn't really going to affect the internet. It's a nice thing to be scared of - but there's no evidence it's going to happen."
Click Online is broadcast on BBC News 24: Saturday at 2030, Sunday at 0430 and 1630, and on Monday at 0030. A short version is also shown on BBC Two: Saturday at 0645 and BBC One: Sunday at 0730 . Also BBC World.
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