Patent ID: 8165992

Claim:
A method for tracking notification messages from a message publisher to a message subscriber, in a publish/subscribe system having one or more entities each configured as one or more of a message publisher, a channel and a message subscriber, the method comprising: subscribing to a meta-channel, said meta-channel receiving descriptions of one or more associated channels, each said channel description indicating how notifications are presented by a publisher, or aggregated or transformed by a publisher so as to supercede notifications received by the publisher acting as a subscriber and thereby reduce a load upon the system, so that a subscriber to a channel having aggregated or transformed notifications receives the aggregation or transformation rather than the superceded notifications, the aggregation or transformation then becoming incorporated into subsequent notifications when the subscriber is configured as a publisher after having further aggregated or transformed what has been received from the channel; receiving a digest of said channel descriptions from said meta-channel, said digest indicating how notifications are superceded thereby enabling a subscriber or a publisher, respectively, to discriminate between channels and to switch to channels providing superceding notifications based on said discrimination, wherein said switching of channels based on said discrimination serves to automatically reconfigure said publish/subscribe system in response to overloading or failure of one or more channels in said system; receiving a digest of one or more transformation description messages from said meta-channel, said digest enabling a subscriber to track evolution of message transformations from raw forms to processed forms and to switch publishers based on said tracking, the evolution progressing from superceded to superceding notifications; and using said transformation description messages to track said evolution of message transformations in order to determine where to subscribe.