TechPublishing Now MS Certified

TechPublishing Now MS Certified
Professor Robert McMillen, MBA Microsoft Certified Trainer and Solutions Expert

Saturday, April 7, 2012

Denial of Service Attacks Take Down Websites and Networks

Denial of Service Attacks Take Down Websites and Networks

By Robert McMillen, Koin’s Tech Guru

As many have heard by now the 4th of July weekend brought a host of website problems as some of the country’s biggest websites and government servers were hit by hackers and fires. In Seattle, a fire that brought down a large data center that hosts websites as big as Microsoft’s Bing was down for up to 36 hours, but that wasn’t the only problem. A Distributed Denial of Service (DDOS) attack hit government websites and now it’s clogging up the internet.

A DDOS attack is a group of computers, in this case an estimated 20,000 of them, are told to simultaneously attack websites of their choosing. This morning it was several large news organizations, cybercrime fighting websites, and US government websites. But that’s pretty tame compared to what’s happening in South Korea. The attack for which they are on the receiving end has effectively brought the entire country’s internet down. It started with just government websites, but the bottleneck caused by the constant pinging from the infected zombie computers has stopped up their internet like a clogged sink.

In the Northwest we are still dealing with the re-routing of websites due to last week’s Seattle fire. We also had a new internet outage for almost all Verizon DSL and FIOS users this morning that caused widespread difficulty getting to most websites. That has mostly been cleaned up as of 11 AM, but so far Verizon is not commenting. It could have been a system wide reboot that stops the zombie attack, or they could have had a failed core router. We should know the answer shortly. Qwest was also affected but it doesn’t appear to have been as widely affected as Verizon. So far Comcast has escaped most of the outages probably due to the fact their customer’s don’t host websites that were affected by the attack.

A DDOS attack is mainly caused by many infected computers being told by a mother ship computer to attack a network, or attack specific websites. In the case of Conficker, or the April Fool’s Day virus, the attacker decided to use that virus for stealing people’s identities. In this case it’s just sending “ping” requests until the connection is broken. When too many computers do this at once it generally causes a lot of outages and slowness. Pinging is a tool used by computer users and technicians to test a connection. In the hands of an attacker it can be used to bring down networks.

Which virus was the cause of this attack? It’s not know yet, but the infected computers are worldwide. South Korea is pointing the blame at North Korea by routing the attack through China. If this is the case then either China or North Korea controls the virus and the zombie computers that are running the attack.

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Published Wednesday, July 08, 2009 12:21 PM by Katatkoin