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Remailers

A remailer enables you to send and receive email while keeping your real email address secret, by retransmitting your email with an anonymous return address. While encryption provides protection from reading your communications, remailing also protects knowledge of your email's true destination -- disguising your real address.

The first widely used remailer was at penet.fi, hosted by Johan Helsingius's in Helsinki, Finland. The site obtained world-wide usage and notoriety for it's audacious global provision of anonymity for the emailing masses in the 1990's. However, he eventually had to close it down after a court case brought by the Church of Scientology successfully forced him to reveal the real email address of a user that had posted information about the religion, rendering its purpose moot in his eyes. However, as is so often the case with information as with life itself, the cat was out of the bag, and other remailer services sprung up to take its place with increasing technology and feature sophistication.

The two most popular type of remailers in use today are summarized below:

Cypherpunk. Also called Type I remailers, and usually incorporate PGP encryption. You can chain Cypherpunk remailers, but each extra node in the chain increases the opportunities for communication interception.

Mixmaster. Also called Type II remailers, originally designed by Lance Cottrell who also invented the orginal anonymizer. Mixmaster remailers are good for chaining to further obscure any connection between the email's source and destination. These remailers divide all messages into fixed size packets, so that all communications between remailers look the same, greatly complicating any attempts at traffic analysis.

Most remailers also vary the retention time before remailing to help protect against time-based analyses.

Resources. The following sites provide information about remailers: