How to survive the five worst technology disasters

From banks to hospitals to the systems that keep the juice flowing to our homes, we are almost entirely dependent on tech. We look at the effect of the five worst 'tech doomsday' scenarios, such as the entire net collapsing, would have on our lives.

Tech doomsday scenario 4: The net goes down

News flash: The internet melted down today as millions of web surfers found themselves redirected to the wrong sites, thanks to problems with the domain name server system.

Can the internet be taken offline? Many experts scoff at the idea, citing too many diverse communications channels, too many redundancies, and an architecture designed to route around failures.

"I think it would be very difficult to take down the whole internet, unless you had a worldwide EMP event that takes everything else down as well," says Dr. Ken Calvert, chair of the University of Kentucky's Department of Computer Science.

"At all levels you have diversity of technology carrying the bits, whether it's satellite, fibre or wireless. There's a lot of redundancy there."

Yet even if the net can't be entirely shut off, short of an act of God (see Tech doomsday scenario 5), attackers can create havoc by attacking it at one of its weakest points: the domain name system.

By hijacking traffic meant for different domains, attackers can drive unsuspecting surfers to malicious sites, effectively take down any site by flooding it with traffic, or simply send everyone looking for Google or Yahoo into the ether - making the net largely useless for a great many people.

"Everybody trusts the DNS, but it's not really trustworthy," says Rod Rasmussen, president and CTO for anti-phishing services firm Internet Identity.

"The system itself isn't well protected. And all you need are a name and a password to take out a DNS server or a particular domain."

Attackers don't even need to attack DNS servers or poison their caches; they can achieve the same effects by taking over large domain registrars.

A successful infiltration of Network Solutions, for example, could put attackers in charge of more than half the domains for all US financial institutions, says Rasmussen.

From there, attackers could redirect surfers to bogus sites and later use their credentials to log in and drain their accounts.

Or they could simply target large domains with huge amounts of traffic, or create havoc by messing with the net's time servers.

NEXT PAGE: What effect would the net going down have on us?

1. We look at the likelihood of these doomsday scenarios
2. Britain goes dark
3. What could happen
4. Wall Street gets e-bombed
5. How long would it take Wall Street to recover?
6. Google is gone
7. What could happen if Google goes down
8. The net goes down
9. What effect would the net going down have on us?
10. God strikes back
11. Could we recover from an act of God?