System and method for controlling congestion in networks

摘要

A congestion controlling device (2) is connected to client terminals (1-1 to 1-i) and contents servers (3-1 to 3-j) via communications lines (51, 52). When a load distributing device (22) receives requests from the client terminals (1-1 to 1-i) that have made the requests for acquisitions of the information, the load distributing device (22) judges whether the situation of the relay processing has satisfied a predetermined condition. If the situation has satisfied the condition, not only the client's requests are regulated, but predetermined messages of either reasons for the regulation or requests to defer the client's requests for a while are notified to the client terminals (1-1 to 1-i). The congestion controlling device (2) may include Web proxy servers (24-1 to 24-n) each including a cache (240-1 to 240-n each). If the information requested by the client terminals has been stored in the cache of the Web proxy server, the information in the cache is transmitted to the client terminals (1-1 to 1-i).