COMMUNICATION APPARATUS, CONTROL METHOD, AND COMPUTER-USABLE MEDIUM FOR SELCTING A NETWORK FOR DATA TRANSMISSION

In a communication apparatus corresponding to a voice-band analog communication path and a network communication path, high-speed and high-reliability data communication is achieved by selecting the appropriate communication path without any complicated user operation. The communication apparatus which performs IP communication and analog communication through an ADSL gateway obtains a communication partner IP address from an SIP proxy when a communication partner telephone number corresponds to a VoIP network, and transmits/receives communication data to/from the communication partner on an IP network based on a file transmission/reception protocol such as FTP, HTTP, or the like. The communication apparatus performs analog facsimile communication on a line switching network when the communication partner telephone number does not correspond to the VoIP network, and performs the analog facsimile communication when the communication partner corresponds to the VoIP network but does not have any digital communication means.