Anonymous remailer

From The IT Law Wiki

An anonymous remailer is a service that allows the sender of an e-mail to hide the source of the e-mail. The anonymous remailer strips the return address information from a message, adds a computer-generated code as a return address and then remail the message from its own server. The effect of doing so is that the recipient receives a message from an anonymous user name at the anonymous remailer’s domain. In many cases, the anonymous remailer maintains the original return address information so that any return mail may be forwarded to the original sender.

For additional security, messages may be forwarded from one anonymous remailer to another, or several, before delivery to its ultimate addressee. Messages can also be encrypted in layers so that in each step along the chain of anonymous remailers only the next recipient is known. While still not foolproof, the discovery of a particular sender’s identity would require disclosure by multiple anonymous remailers.

In the alternative, anonymous remailers that do not retain any of the original message information can provide an even higher level of security. Discarding the original message information, however, precludes return mail to an anonymous sender or assignment of the same anonymous address to a sender’s subsequent messages.