Nym remailer

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A Nym remailer is a pseudonymizing remailer that accepts encrypted or unencrypted messages, anonymizes them and forwards them.

Alternative names are "Nym Server" or "Pseudonym Server" (English also "pseudonymous server" and "pseudonymous remailer"). Nym is also an abbreviation for pseudonym .

General

In contrast to Cypherpunk and Mixmaster remailers , the Nym server allows replies to be sent to the original sender despite ignorance of the original sender. The service thus enables bidirectional communication in which, in extreme cases, none of the communication partners has knowledge of the identity of the other.

The Nym server, like other remailers, removes all header information from the received emails that could be used to identify the sender. Instead of his own standard address, he enters a saved pseudonym address assigned to the sender in the sender field.

Replies to such pseudonymized e-mails are sent to this address and forwarded by the Nym server to the real recipient. How the remailer manages the assignment of real senders to pseudonyms determines the security of the facility.

Functioning of today's common Nym servers

The operators of these services cannot determine the identity of their users either. This is achieved by every exchange with the Nym server - including the registration of a new pseudonym address - using a chained Cypherpunk or Mixmaster remailer.

In order to deliver incoming e-mails to the pseudonymous recipient, the Nym server also stores information about one or more remailer chains that the user originally selects for communication with the server. In order to get such a message on the way to the waiting recipient, it is sufficient for the Nym server to know the first remailer of one of these chains. All of the following are encrypted and also remain hidden from the Nym server.

Due to the fluctuating reliability of many remailers, these remailer chains often have to be adjusted. Maintaining a so-called nym account is therefore time-consuming. That is why many convenient remailer client programs have been created that take special care of the configuration and subsequent manipulation of a Nym account.

Beginnings: The Penet Remailer

The first publicly accessible pseudonym remailer was operated by Johan "Julf" Helsingius . Helsingius made its service available on anon.penet.fi from 1993 .

Functionality and weakness of the pseudo-anonymous penet remailer

The Penet server was based on some Perl scripts. The service was available to every Internet user. E-mail that reached Penet was depersonalized and the sender was anonNNNN@anon.penet.fi (N is any digit.). Helsingius' remailer saved the pseudonym anonNNNN together with the original e-mail address in a database . On the way back, e-mails that were sent to a pseudonym could be forwarded to the real address. However, the database is also the weak point of this type of remailer because it is theoretically possible to subsequently associate the e-mail traffic with real people.

Attacks against the server

Helsingius soon received various inquiries about real sender addresses. After an internal paper of the Scientology group was posted via Penet in the newsgroup alt.religion.scientology in 1995 , Scientology began to take legal action against Helsingius, but initially unsuccessfully.

Allegations by the British newspaper Observer ( 1996 ) that child pornography had been posted on the server could quickly be refuted because the system did not allow files the size of the allegedly published photos to pass through (maximum 15  KB ).

The decision of a Finnish court in favor of Scientology suggested that the confidentiality of letters did not apply to e-mail. This fact and persistent attacks from the Internet finally brought Johan Helsingius to take the server offline for good.

See also

literature

Web links

Individual evidence

  1. ↑ http://www.fitug.de/archiv/presse/penet1.html