XSEND(1)                                                 XSEND(1)

     NAME
          xsend, xget, enroll - secret mail

     SYNOPSIS
          xsend person
          xget
          enroll

     DESCRIPTION
          These commands implement a secure communication channel; it
          is like mail(1), but no one can read the messages except the
          intended recipient.  The method embodies a public-key cryp-
          tosystem using knapsacks.

          To receive messages, use enroll; it asks you for a password
          that you must subsequently quote in order to receive secret
          mail.

          To receive secret mail, use xget. It asks for your password,
          then gives you the messages.

          To send secret mail, use xsend in the same manner as the
          ordinary mail command.  (However, it will accept only one
          target).  A message announcing the receipt of secret mail is
          also sent by ordinary mail.

     FILES
          /usr/spool/secretmail/*.key: keys
          /usr/spool/secretmail/*.[0-9]: messages

     SEE ALSO
          mail (1)

     BUGS
          It should be integrated with ordinary mail.
          There is no provision for intermachine mail.
          The announcement of secret mail makes traffic analysis pos-
          sible.