Social Networks, Privacy, and the Semantic Web
by Jennifer Golbeck
FOAF is short for Friend-of-a-Friend, and it is a Semantic Web vocabulary for representing information about people and their relationships. Because FOAF is a Semantic Web project the files are written in OWL, a machine readable language. This means they can be easily read, processed, and aggregated from distributed sources.
FOAF information is generated from a lot of places. People can create their own FOAF files by hand, or by using Foaf-a-Matic. The largest sources of FOAF data, however, are web-based social networks that choose to share their user's information in FOAF form, as well as in HTML form. LiveJournal, Tribe.net, eCademy, and Buzznet are just a few of the networks that publish users' data in FOAF. In 2004, Howard Dean's campaign was also collecting social network information, by recording which visitors sent emails through the site, inviting their friends to come visit. They published this data as FOAF, as well.
Plink encountered all of this information, freely available on the web, and displayed what it found as part of its website. The result was a nice website that showed all of the data about a person from a variety of sources. It also inspired a lot of angry email from people who never "signed up" for Plink and were very surprised to see their information there. As a result, Plink was forced to shut down.
As we consider this, let's all share a moment of silence for Plink, may it rest in peace.
What are your ideas about privacy on the Semantic Web? Are there systems you think could be or should be deployed?