Event delivery system, rendezvous node, broker node, load distribution method for event delivery system, load distribution method for rendezvous node, delivery route construction method for broker node, storage medium storing load distribution program, and storage medium storing delivery route construction program

A load distribution method for an event distribution system comprising:

• monitoring a traffic volume of event information issued by a publisher node that issues event information containing a content of a generated event and advertisement information advertising the event at a rendezvous node that makes information management related to a generated event;
• determining specific event information subject to load distribution from among the event information when the traffic volume monitored by the traffic volume monitoring exceeds a predetermined value;
• performing route detection for detecting an aggregation point node and a branch point node for changing a current delivery route of the specific event information determined by the specific event determination from among broker nodes that transfer the event information and the advertisement information issued by the publisher node and request information issued by a subscriber node that issues request information for receiving desired event information;
• and
• performing route construction for constructing a new delivery route of the specific event information going through the aggregation point node and the branch point node detected by the route detection, bypassing the rendezvous node.

A load distribution method for a rendezvous node, comprising:

• monitoring a traffic volume of event information passing through a rendezvous node by the rendezvous node included in an event delivery system to deliver event information containing a content of an event generated in a publisher node to a subscriber node;
• and
• determining specific event information subject to load distribution from among the event information when the traffic volume monitored by the traffic monitoring exceeds a predetermined value, wherein
• the event information is composed of identification elements made up of a plurality of hierarchical levels, and
• the specific event information determination includes
• performing upper event identification for identifying a type of the event information with at least two levels of identification elements from a top of the hierarchy of the identification elements,
• performing traffic measurement for measuring the traffic volume for each type of the event information identified by the upper event identification, and
• performing event detection for determining at least one event information in decreasing order of the traffic volume for each type of the event information measured by the traffic measurement as the specific event information.

A non-transitory computer readable medium storing a load distribution program causing a computer to execute:

• a traffic monitoring processing, by a traffic monitoring unit of a rendezvous node, for monitoring a traffic volume of event information containing a content of an event generated in a publisher node and passing through the rendezvous node;
• and
• a specific event determination processing, by a specific event determination unit of the rendezvous node, for determining specific event information subject to load distribution from among the event information when the traffic volume monitored by the traffic monitoring unit exceeds a predetermined value, wherein
• the event information is composed of identification elements made up of a plurality of hierarchical levels, and
• the program causes a computer to execute, in the specific event determination processing,
• an upper event identification processing, by an upper event identification unit included in the specific event determination unit, that identifies a type of the event information with at least two levels of identification elements from a top of the hierarchy of the identification elements,
• a traffic measurement processing, by a traffic measurement unit included in the specific event determination unit, that measures the traffic volume for each type of the event information identified by the upper event identification unit, and
• an event detection processing, by an event detection unit included in the specific event determination unit, that determines at least one event information in decreasing order of the traffic volume for each type of the event information measured by the traffic measurement unit as the specific event information.