From: cal@hplb.hpl.hp.com (Colin Low)
Subject: TECH: Notification Service Software
Date: Thu, 9 Oct 1997 13:38:56 GMT
Organization: Hewlett-Packard Laboratories, Bristol, England


This is not an advertisment - it contains details of software we
are using for distributed virtual environment development and which
we are making available for non-commercial use:


                  Keryx Internet Notification Service
                  -----------------------------------

Turn the Internet into a giant operating system.  If you have ever wanted
to write a program that waits on an event happening somewhere (anywhere) in
the world, so that it responds to the event automatically, then you will
probably want this notification service.

Events are things that happen; notifications are descriptions of events.
The notification service creates a notional "cloud" of event notifications
that you can tap into by describing the kind of notifications you want to
receive.  The notification service provides a loose and often anonymous
coupling between sources of event notifications, and their consumers, so
that you can wait for an event to happen without knowing anything in
advance about the sources of the notification.

Typical applications are:

 o instrumented environments, such as domestic control and security, where
   you might like to produce various alarm and status notifications.
   
 o distributed virtual environments, so that events in the virtual world can
   be exported, and events in the real world can be monitored - for example,
   you could use notifications to monitor the position and activities of a 
   person in the real world, and update a VRML scene.
   
 o WWW site notifications, for monitoring document changes.

 o Internet Push - don't waste bandwidth pulling stuff that you might never 
   look at. Use a genuine push technology to receive notifications
   about changes, and automatically fetch stuff on demand.
 
 o communications, where you could use automatic location notifications
   to route your telephone calls.
   
 o loosely-coupled distributed workflow sytems, with notifications providing
   the rendezvous and synchonisation function.
   
 o distributed agents - notifications provide an elegant anonymous rendezvous
   between agents. E.g. marketplace applications for selling and buying.

The Keryx Notification Service is written in Java. Full source
code (subject to license) and documentation is available from

               http://keryxsoft.hpl.hp.com

               Keryx - A Nervous System for the Internet


Colin Low
Hewlett Packard Laboratories
Bristol, UK
cal@hplb.hpl.hp.com