How to build privacy into a social network
Arvind Narayanan used the example of LiveJournal to scout out some features which could be built into social networks to allow greater control over sharing and privacy.
First: Everyone But X.
“This is an example of a whole class of access control primitives that make no sense from the traditional computer science security perspective. If an item is visible to every logged-in user except X, X can always create a fake (“sybil”) account to get around it.
However, let me give you one simple example that I hope will immediately convince you that everyone-but-X is a good idea: your sibling is on your friends list and you want to post about your sex life. It’s not so much that you want to prevent X from having access to your post, but rather that both of you prefer that X didn’t have access to it. The relationship is not adversarial. Extrapolating a little bit, most users can benefit from everyone-but-X privacy in one context or another, but amazingly, no social network has thought of it.”
Second: Stupidly Easy Friend Lists.
“Having to manually manage friend-lists puts it beyond the patience level of the average user, and offers no hope of getting users who already have several hundred uncategorized friends to start categorizing. But technology can help: I’ve written about automated friend-list clustering and classification before.”