| 摘要 |
PROBLEM TO BE SOLVED: To provide a system which, when a call is originated from an extension telephone to a telephone network of outside lines, leaves information enabling one to identify the originator as a call history without leaving the outside line telephone number of the originator inside the extension telephone, allowing a user to grasp on the extension telephone side to where the call was dispatched and also, even if the extension telephone is lost, making it possible to reduce the risk of leaking customer information, and which, even when a caller from the extension telephone does not know information for identifying the originator, allows him or her to know a number for identifying the originator easily.SOLUTION: When a request is received from an extension telephone number inquiring about a system number corresponding to a called number, outside line information data is searched for a system number correlated uniquely to the called number. When not found in registry, a new system number corresponding uniquely to the called number is issued. |
