\section{Notifications}
Since a meeting has a single location, other users can
immediately see any new transactions added to a meeting.  This adds a
real-time flavor to {\it Discuss}; users can reply to transactions
immediately, and create an on-going conversation among several
participants.  To facilitate this, {\it Discuss} allows users to be
notified when a new transaction is added to a meeting.

{\it Discuss} uses the {\it Zephyr} Notification Service to inform
interested users of new transactions in meetings.  {\it Zephyr} is a
notice transport system that delivers interactive
messages in a networked workstation environment.  Users register which
classes of messages they are interested in; {\it Zephyr} will deliver
messages to the appropriate users.

When a {\it Discuss} server adds a new transaction to a meeting, it
sends out a {\it Zephyr} notice.  Since this notice contains
information such as the subject and author of the transaction, the
transmission of the notice should not violate the privacy of the
meeting.  The server does not send out public notifications of new
transactions in private meetings.  If the meeting is publically
readable (read access to ``*''), it sends out the {\it Zephyr} message
to recipient ``*.''  Anybody can subscribe to these messages.  If
the meeting is private, then the {\it Zephyr} message is only sent to
those users who have read access to the meeting.
