IP-PBX, IP-PBX system, IP terminal control program

An IP-PBX system comprising:

• an IP-PBX;
• a plurality of IP terminals;
• and
• a network connecting said IP-PBX and said plurality of IP terminals,
• wherein said IP-PBX comprises:
• a software-based built-in control unit;
• at least one card slot into which a control card is plugged;
• and
• a data bus connecting said software-based built-in control unit and said card slot,
• wherein said software-based built-in control unit includes:
• a first management unit managing up to a first number of IP terminals and connected to said network;
• and
• an IP terminal registering unit connected to said first management unit, said card slot and said network,
• wherein said control card includes a second management unit managing up to a second number of IP terminals and connected to said network,
• wherein said IP terminal registering unit compares a current number of IP terminals managed by one of said first management unit and said second management unit with corresponding one of said first number and said second number when one of said plurality of IP terminals requests communication, said one IP terminal having an ID number and an IP address,
• wherein, if said current number is smaller than said one number, said IP terminal registering unit associates said one management unit with said ID number and said IP address, and said one management unit manages said one IP terminal,
• wherein, if said current number is equal to said one number, said IP terminal registering unit associates another of said first management unit and said second management unit with said ID number and said IP address, and said another management unit manages said one IP terminal.

A computer program product comprising:

• a computer usable medium having computer readable program code embodied therein configured for controlling an IP-PBX,
• said IP-PBX comprising at least one card slot into which a control card is plugged, said control card managing up to a second number of IP terminals,
• said computer program product comprising:
• computer readable code as a first code configured to cause a computer to manage up to a first number of IP terminals;
• computer readable code configured to cause a computer to compare a current number of IP terminals managed by one of said first code and said control card with corresponding one of said first number and said second number when an IP terminal requests communication, said IP terminal having an ID number and an IP address;
• computer readable code configured to associate said one of said first code and said control card with said ID number and said IP address and to have said one of said first code and said control card manage said IP terminal, if said current number is smaller than said one number;
• and
• computer readable code configured to associate another of said first code and said control card with said ID number and said IP address and to have said another of said first code and said control card manage said IP terminal, if said current number is equal to said one number.