Patent attributes
A communication system in accordance with the present invention is provided with a terminal device and a call connection server. The terminal device comprises a personal computer 70u in which software is installed for performing a call connection process, and a dedicated telephone terminal 60u which is connected to the personal computer 70u and capable of digital encoding voice band signals. The call connection server comprises a SIP server 11 which performs a call connection process with the personal computer 70u and so forth, a database server 12 which stores related information about the users of an IP telephone service, telephone numbers and designation addresses (IP addresses) in association with each other, and a call agent 13 which performs a call connection process on the basis of the information stored in the database server 12.