How Egypt Cut Off the Internet (and How a U.S. 'Kill Switch' Might Work)
By Doug Aamoth on January 28, 2011
REUTERS/Amr Dalsh
egypt, internet, internet access
Reports have now verified that Eqypt has cut off access to the internet amid political protests. Renesys, an internet monitoring firm based in Manchester, New Hampshire, calls the situation "an action unprecedented in Internet history," according to a company blog post.
The development of an internet "kill switch" that our own government could use in the case of a national emergency has been proposed here in the U.S., and if we take a look at how Egypt has already flipped its own kill switch, it may give us more insight into how such a system would work here.
The Basics of an Internet Connection
On the simplest of levels, your computer connects to the internet through an internet service provider (ISP)—Comcast, Time Warner, Qwest, Verizon, etc.—and your service provider either connects directly to all the other internet service providers around the world or to a larger internet service provider that then connects to all the others.
When you open up your web browser and type a domain name into the address bar—say Time.com, for instance—your service provider sends a lightning-quick request to whichever service provider Time.com uses to make its web pages publicly available on the internet.
The computer that holds all of Time.com's web pages sends a response back through its internet service provider basically saying, "Yes, we're online. Here's the web page you requested."
The Domain Name System
That handshake-type scenario is routed through a domain name system (DNS) server. Your computer is identified with a unique numeric code called an internet protocol (IP) address. Time.com's computers also have their own IP addresses. The DNS server converts the plain-English web address that you typed into your browser from www.time.com to the appropriate numeric IP address so it can be routed through the internet between your computer and whichever computer at Time.com holds the web page you've requested.
In most cases, your internet service provider automatically designates a DNS server for your connection to use. But if that particular DNS server gets knocked offline somehow, you won't be able to negotiate any sort of internet requests. Your computer will send a request for a web page through your ISP, which will try to route it through the assigned DNS server and, if that server's not available, you won't get an answer back.
The beauty of how the internet is structured, though, is that you can use any of a number of publicly-available DNS servers if the one your ISP assigned you has been knocked offline. For instance, the DNS server that my Comcast connection uses got knocked offline for an entire day a couple months ago and I was able to manually configure my wireless router to connect through Google's free DNS server instead. It's tricky, but it works.
Read more: http://techland.time.com/2011/01/28/how-egypt-cut-off-the-internet/#ixzz1CRxQHo36
Egypt's DNS Servers
The Egyptian government has been able to cut off most of the country's internet access simply by shutting down the various DNS servers used by Egyptian internet service providers. As such, any requests for web pages initiated from inside Egypt have been unsuccessful since there aren't any available DNS servers to facilitate the hand-offs, and any requests for websites located inside Egypt coming from computers anywhere else in the world haven't worked either.
While this has affected most of Egypt's internet traffic, some people are able to work around the issue by manually using DNS servers that haven't been taken offline—similar to the method I used when Comcast's DNS server went down. BGPmon.com is reporting that 88% of Egypt's internet traffic has been knocked offline, which seems to indicate that 12% of those who are still able to access the internet there are either using alternative DNS servers or haven't had their DNS servers taken offline yet (apparently some dial-up internet connections are still able to get through, for instance).
The Kill Switch
While images of a big red button housed inside a Plexiglass case that can only be unlocked by two simultaneous key twists of top government officials seem to fit the idea of how such an internet kill switch would work, the reality is far more mundane. In Egypt's case, the internet service providers that operate within the country agree to let the government shut down the commonly-used DNS servers if they see fit to do so.
The BBC reports that one of Egypt's big internet service providers, Vodafone, issued an e-mail statement simply stating that the company was instructed to shut down its DNS servers. "Under Egyptian legislation the authorities have the right to issue such and order and we are obliged to comply with it," said the statement.
The same order was almost certainly issued to all the other internet service providers operating inside Egypt and, just like that, the internet went down.
Read more: http://techland.time.com/2011/01/28/how-egypt-cut-off-the-internet/#ixzz1CRxyMwL8
By Doug Aamoth on January 28, 2011
REUTERS/Amr Dalsh
egypt, internet, internet access
Reports have now verified that Eqypt has cut off access to the internet amid political protests. Renesys, an internet monitoring firm based in Manchester, New Hampshire, calls the situation "an action unprecedented in Internet history," according to a company blog post.
The development of an internet "kill switch" that our own government could use in the case of a national emergency has been proposed here in the U.S., and if we take a look at how Egypt has already flipped its own kill switch, it may give us more insight into how such a system would work here.
The Basics of an Internet Connection
On the simplest of levels, your computer connects to the internet through an internet service provider (ISP)—Comcast, Time Warner, Qwest, Verizon, etc.—and your service provider either connects directly to all the other internet service providers around the world or to a larger internet service provider that then connects to all the others.
When you open up your web browser and type a domain name into the address bar—say Time.com, for instance—your service provider sends a lightning-quick request to whichever service provider Time.com uses to make its web pages publicly available on the internet.
The computer that holds all of Time.com's web pages sends a response back through its internet service provider basically saying, "Yes, we're online. Here's the web page you requested."
The Domain Name System
That handshake-type scenario is routed through a domain name system (DNS) server. Your computer is identified with a unique numeric code called an internet protocol (IP) address. Time.com's computers also have their own IP addresses. The DNS server converts the plain-English web address that you typed into your browser from www.time.com to the appropriate numeric IP address so it can be routed through the internet between your computer and whichever computer at Time.com holds the web page you've requested.
In most cases, your internet service provider automatically designates a DNS server for your connection to use. But if that particular DNS server gets knocked offline somehow, you won't be able to negotiate any sort of internet requests. Your computer will send a request for a web page through your ISP, which will try to route it through the assigned DNS server and, if that server's not available, you won't get an answer back.
The beauty of how the internet is structured, though, is that you can use any of a number of publicly-available DNS servers if the one your ISP assigned you has been knocked offline. For instance, the DNS server that my Comcast connection uses got knocked offline for an entire day a couple months ago and I was able to manually configure my wireless router to connect through Google's free DNS server instead. It's tricky, but it works.
Read more: http://techland.time.com/2011/01/28/how-egypt-cut-off-the-internet/#ixzz1CRxQHo36
Egypt's DNS Servers
The Egyptian government has been able to cut off most of the country's internet access simply by shutting down the various DNS servers used by Egyptian internet service providers. As such, any requests for web pages initiated from inside Egypt have been unsuccessful since there aren't any available DNS servers to facilitate the hand-offs, and any requests for websites located inside Egypt coming from computers anywhere else in the world haven't worked either.
While this has affected most of Egypt's internet traffic, some people are able to work around the issue by manually using DNS servers that haven't been taken offline—similar to the method I used when Comcast's DNS server went down. BGPmon.com is reporting that 88% of Egypt's internet traffic has been knocked offline, which seems to indicate that 12% of those who are still able to access the internet there are either using alternative DNS servers or haven't had their DNS servers taken offline yet (apparently some dial-up internet connections are still able to get through, for instance).
The Kill Switch
While images of a big red button housed inside a Plexiglass case that can only be unlocked by two simultaneous key twists of top government officials seem to fit the idea of how such an internet kill switch would work, the reality is far more mundane. In Egypt's case, the internet service providers that operate within the country agree to let the government shut down the commonly-used DNS servers if they see fit to do so.
The BBC reports that one of Egypt's big internet service providers, Vodafone, issued an e-mail statement simply stating that the company was instructed to shut down its DNS servers. "Under Egyptian legislation the authorities have the right to issue such and order and we are obliged to comply with it," said the statement.
The same order was almost certainly issued to all the other internet service providers operating inside Egypt and, just like that, the internet went down.
Read more: http://techland.time.com/2011/01/28/how-egypt-cut-off-the-internet/#ixzz1CRxyMwL8
