CAcert.org is a community-driven certificate authority that issues free public key certificates to the public (unlike other certificate authorities which are commercial and sell certificates). CAcert has over 159,000 verified users and has issued over 529,000 certificates as of December 2009.
These certificates can be used to sign and encrypt email, authenticate and authorize users connecting to websites and secure data transmission over the Internet. Any application that supports the Secure Socket Layer (SSL) can make use of certificates signed by CAcert, as can any application that uses X.509 certificates, e.g. for encryption or code signing and document signatures.
To create higher-trust certificates, users can participate in a web of trust system whereby users physically meet and verify each other's identities. CAcert maintains the number of assurance points for each account. Assurance points can be gained through various means, primarily by having one's identity physically verified by users classified as "Assurers" or by "Trusted Third Parties" such as public notaries.
To learn more about CACert and get started with your own secure certificates, visit the team at Booth 15.