Patent ID: 8416434

Claim:
A communication terminal apparatus including a network facsimile device having network functions and directly connected to an IP telephone network, and a SIP adapter device connected to the IP telephone network and to the network facsimile device via an analog port to enable communication based on Session Initiation Protocol SIP for communication control, the SIP adapter device comprising: a circuit unit including a voice coder/decoder for converting an analog facsimile signal received from the network facsimile device via the analog port into a packet; a memory unit in which there are preliminarily registered a first own IP telephone number for use in Peer-to-Peer communication defined as communication performed between a plurality of communication terminal apparatuses and a second own IP telephone number for use in Fax over IP communication defined as communication performed by deeming a transmission signal as a voice signal; and a controller for causing the network facsimile device, when a Peer-to-Peer communication request is received from the network facsimile device via the IP telephone network, to implement the Peer-to-Peer communication with the IP telephone network by using the first own IP telephone number and causing the network facsimile device, when a Fax over IP communication request is received from the network facsimile device via the analog port, to implement the Fax over IP communication by means of the voice coder/decoder by using the second own IP telephone number, wherein the first own IP telephone number is a first IP telephone number of the SIP adapter device, and the second own IP telephone number is a second IP telephone number of the SIP adapter device, such that the SIP adapter device has two IP telephone numbers.