The UK "Porn" Filter Blocks Kids' Access To Tech, Civil Liberties Websites
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I checked my own personal web site first, www.bsdly.net. I was a bit surprised to find that it was blocked in the default Parental control regime.
Next I tried www.usenix.org, the main site for USENIX, the US-based but actually quite international Unix user group. This also turned out to be apparently blocked in the Parental control regime.
You will have guessed by now that I'm a civil liberties man, so the next site URL I tried was www.eff.org, which was also blocked by the Parental Control regime.
A little closer to home for UK kids, I thought perhaps a thoroughly benign organization such as Amnesty International would somehow be pre-approved. But no go: I tried the UK web site, amnesty.org.uk, and it, to was blocked by the Parental Control regime.