Network system and communication band control method thereof

A communication band control method for controlling a communication band of a network system having a plurality of local nodes connected therewith, each of said local nodes taking the steps of:

• obtaining band information required for controlling a communication band from a communication application program;
• storing said obtained band information as the band information of the local node and delivering said band information to all the local nodes connected with said network;
• storing band information delivered by other local nodes as band information of the other local nodes;
• obtaining a current band traffic for the local node to which it belongs on the basis of the band information of the local node and the band information of the other local nodes, which has been stored;
• and
• assuming the current band traffic for the local node to which it belongs that is obtained to be the traffic of said network and controlling the band traffic of the local node on the basis of that assumption.

A network system having a plurality of local nodes connected therewith, said local nodes each including a communication application programs, by which the local node is operated, each of said local nodes comprising:

• a band information obtaining unit which obtains band information required for controlling a communication band from said communication application program;
• a band information managing table which stores said band information obtained by said band information obtaining unit as the band information of the local node;
• a band information delivery unit which delivers the band information of the local node to the other local nodes connected to said network;
• a band information receiver which receives the band information delivered by said band information delivery units of the other local nodes and storing the band information of the other local nodes in said band information managing table;
• a band traffic calculator which calculates a current band traffic for the local node to which it belongs on the basis of the band information of the local node to which it belongs and the band information of the other local nodes stored in said band information managing table;
• and
• said band traffic calculator assuming current band traffic that is obtained to be the band traffic of said network and controlling the band traffic of the local node to which it belongs on the basis of that assumption.