Patent ID: 8644307

Claim:
A communication transfer apparatus comprising: a presence information storage section which stores information on presence or absence of a user at each terminal and information on priorities of terminals for each of users, wherein said terminals for each of users are located in a local IP network to which a common global Internet Protocol address is assigned; a masquerade table including a plurality of records, on each of which recorded is a global Internet Protocol address common among said plurality of records, a global port number, a local Internet Protocol address, and a local port number; a called terminal detecting section which detects a called terminal based on signals received via a global IP network or outputs fnmn said terminals; a presence determining section which determines presence or absence of a user at the called terminal detected by said called terminal detecting section by referring to the information on presence or absence of said user at the detected called terminal stored in said presence information storage section; a transfer destination identifying section which identifies a terminal having a next priority by referring to the information on priorities a terminals for said user at the detected called terminal stored in said presence information storage section if said presence determining section determines absence of a user at the called terminal detected by said called terminal detecting section; and a record rewriting section which retrieves a record which corresponds to the called terminal from said masquerade table including said plurality of records and changes a local Internet Protocol address of the retrieved record into a local Internet Protocol address of the terminal identified by said transfer destination identifying section, wherein two or more transfers take place with respect to two or more different called terminals located in the local IP network to which the common global Internet Protocol address is assigned.