The fact that governments can kill the internet, has moved from informed speculation into established fact, as witnessed in the recent events in Egypt. The communication infrastructure that we all use daily, is for the most part owned and maintained by "private" corporations and the government.
If a national security event were to take place, the government could very easily take control of, or completely stop all avenues of communication, limiting incoming and outgoing news.
So how do you communicate if your government decides to pull the plug?
Wired has published an excellent Wiki article detailing a number of ways in which you can communicate with friends, family and the world.
Some highlights are:
CB Radio: Short for "Citizens Band" radio, these two-way radios allow communication over short distances on 40 channels. You can pick one up for about $20 to $50 at Radio Shack, and no license is required to operate it.
Ham radio: To converse over these radios, also known as "amateur radios," you have to obtain an operator's license from the FCC. Luckily, other Wired How-To contributors have already explained exactly what you need to do to get one and use it like a pro.
Enable Twitter via SMS: Though the thought of unleashing the Twitter fire hose in your text message inbox may seem horrifying, it would be better than not being able to connect to the outside world at all. The Twitter website has full instructions on how to redirect tweets to your phone.
Return to dial-up: According to an article in the BBC about old tech's role in the Egyptian protests, "Dial-up modems are one of the most popular routes for Egyptians to get back online. Long lists of international numbers that connect to dial-up modems are circulating in Egypt thanks to net activists We Re-Build, Telecomix and others."
Dial-up can be slow. Often, there is a lightweight mobile version of a site that you can load from your desktop browser quickly despite the limitations of dial-up. Examples: mobile.twitter.com, m.facebook.com, m.gmail.com.
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