Patent ID: 11949812
Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
Field: Telecommunications (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. An ENUM server for receiving an ENUM query from another network that includes a sender terminal and transmitting, to the other network, connection destination information that corresponds to a call destination number of a receiver terminal that is indicated in the ENUM query and managed in a local network, the ENUM server comprising:
a signal reception unit, including one or more processors, configured to receive an ENUM query from the other network;
a congestion detection unit, including one or more processors, configured to collect traffic information regarding calls that include call destination numbers from call processing apparatuses in the local network, calculate a call amount per unit time for each call destination number, and store the call amounts per unit time as calculated call amount information in a storage unit, and also configured to extract a call destination number included in the received ENUM query, reference the calculated call amount information, and determine that calls to the extracted call destination number are in a congested state if the call amount regarding the extracted call destination number exceeds a predetermined threshold value;
a limit processing unit, including one or more processors, configured to, if it was determined that the call destination number included in the received ENUM query is in the congested state, determine whether or not the ENUM query is to be a limit target based on predetermined limit processing;
and a signal response unit, including one or more processors, configured to, if it was determined that the ENUM query is the limit target, generate an ENUM answer that indicates connection unavailability, set a Time To Live (TTL) value of the ENUM answer to 0, and transmit the ENUM answer to the other network.