Bruce Schneier (security guru) just finished an interview with Freaknomics. In the interview he answers a lot of questions of Freaknomics readers. His answers include a lot of links to articles he has posted on various topics. Well worth a read.

Q: Is there any benefit to password protecting your home Wifi network? I have IT friends that say the only real benefit is that multiple users can slow down the connection, but they state that there is no security reason. Is this correct?
A: I run an open wireless network at home. There’s no password, and there’s no encryption. Honestly, I think it’s just polite. Why should I care if someone on the block steals wireless access from me? When my wireless router broke last month, I used a neighbor’s access until I replaced it.

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