| 摘要 |
A telephone exchange system includes a connection interface connecting a communication line and a plurality of extension telephones, a database having a dial-in conversion table registering a received number in association with a number after conversion for a dial-in incoming call, and an extension number table registering an extension telephone in association with an extension number of the extension telephone, and a main controller connected to the connection interface and the database. When the dial-in incoming call comes from the communication line, the main controller retrieves an extension number which coincides with the received number from the extension number table. When there is an extension number which coincides with the received number, the main controller causes an extension telephone corresponding to the extension number to ring. |
