Method and apparatus for priority control of incoming calls at ISDN terminals

Claim 1

A method of controlling a priority order for an incoming call of an integrated service digital network (ISDN) to a plurality of ISDN terminals connected to an ISDN user network interface, said terminals having a common subscriber number telecommunication service attribute information and no subaddress, said network including a network termination which supplies a SETUP message containing a calling party number and a telecommunication service attribute information, the method comprising the steps of: (a) providing in each terminal a timer and starting the timer when the SETUP message of an incoming call of the ISDN is received in a terminal; (b) checking an ISDN compatibility to determine whether a terminal responds to the SETUP message by comparing the telecommunication service attribute information contained in the received SETUP message with the telecommunication service attribute information given to the terminal; (c) providing in each terminal a memory storing at least one of waiting time set values for establishing a desired priority order concerning the type of the telecommunication service attribute information; (d) determining whether the memory in said terminal stores the telecommunication service attribute information contained in the received SETUP message; (e) where the telecommunication service attribute information is stored in said memory, outputting a setting signal for one of the waiting time set values, which corresponds to the telecommunication service attribute information; (f) comparing a count of said timer with said waiting time set value and outputting a count-up signal when a timing operation of the timer has continued for at least said waiting time set value; and (g) upon detection of said count-up signal, responding to the network with an ISDN CONNECT message which indicates that the terminal is eligible to accept said incoming call, whereby a priority order for responding to the incoming call of the ISDN in the plurality of ISDN terminals is variable according to a telecommunication service attribute of the incoming call of the ISDN.

Claim 2

A method of controlling a priority order for an incoming call of an integrated service digital network (ISDN) to a plurality of ISDN terminals connected to an ISDN user network interface, said terminals having a common subscriber number telecommunication service attribute information and no subaddress, said network including a network termination which supplies a SETUP message containing a calling party number and a telecommunication service attribute information, the method comprising the steps of: (a) providing in each terminal a timer and starting the timer when the SETUP message of an incoming call of the ISDN is received in a terminal; (b) checking an ISDN compatibility to determine whether a terminal responds to the SETUP message by comparing the telecommunication service attribute information contained in the received SETUP message with the telecommunication service attribute information given to the terminal; (c) providing in each terminal a memory storing at least one of waiting time set values for establishing a desired priority order concerning the type of the telecommunication service attribute information; (d) determining whether the memory in said terminal stores the telecommunication service attribute information contained in the received SETUP message; (e) where the telecommunication service attribute information is stored in said memory, outputting a setting signal for one of the waiting time set values, which corresponds to the telecommunication service attribute information; (f) comparing a count of said timer with said waiting time set value and outputting a count-up signal when a timing operation of the timer has continued for at least said waiting time set value; and (g) upon detection of said count-up signal, responding to the network with an ISDN CONNECT message which indicates that the terminal is eligible to accept said incoming call, whereby a priority order for responding to the incoming call of the ISDN in the plurality of ISDN terminals is variable according to a telecommunication service attribute of the incoming call of the ISDN.

Claim 3

A method of controlling a priority order for an incoming call of an integrated service digital network (ISDN) to a plurality of ISDN terminals connected to an ISDN user network interface, said terminals having a common subscriber number telecommunication service attribute information and no subaddress, said network including a network termination which supplies a SETUP message containing a predetermined calling party number and telecommunication service attribute information said method comprising the steps of: (a) providing a timer in each terminal and starting a timer when the SETUP message of an incoming call of the ISDN is received in a terminal; (b) checking an ISDN compatibility to determine whether a terminal responds to the SETUP message by comparing the telecommunication service attribute information contained in the received SETUP message with the telecommunication service attribute information given to the terminal; (c) providing in each terminal a memory storing a waiting time set value for establishing a desired priority order concerning a predetermined calling party number; (d) determining whether the memory in the terminal stores the calling party number contained in the received SETUP message; (e) where the calling party number is stored in said memory, outputting a setting signal for the waiting time set value which corresponds to the calling party number; (f) comparing a count of said timer with said waiting time set value and outputting a count-up signal when a timing operation of the timer has continued for at least said waiting time set value; and (g) upon detection of said count-up signal, responding to the network with an ISDN CONNECT message which indicates that the terminal is eligible to accept said incoming call, whereby a priority order for responding to the ISDN incoming call in the plurality of ISDN terminals is variable according to the predetermined calling party number.

Claim 4

A method of controlling a priority order for an incoming call of an integrated service digital network (ISDN) to a plurality of ISDN terminals connected to an ISDN user network interface, said terminals having a common subscriber number telecommunication service attribute information and no subaddress, said network including a network termination which supplies a SETUP message containing a predetermined calling party number and telecommunication service attribute information said method comprising the steps of: (a) providing a timer in each terminal and starting a timer when the SETUP message of an incoming call of the ISDN is received in a terminal; (b) checking an ISDN compatibility to determine whether a terminal responds to the SETUP message by comparing the telecommunication service attribute information contained in the received SETUP message with the telecommunication service attribute information given to the terminal; (c) providing in each terminal a memory storing a waiting time set value for establishing a desired priority order concerning a predetermined calling party number; (d) determining whether the memory in the terminal stores the calling party number contained in the received SETUP message; (e) where the calling party number is stored in said memory, outputting a setting signal for the waiting time set value which corresponds to the calling party number; (f) comparing a count of said timer with said waiting time set value and outputting a count-up signal when a timing operation of the timer has continued for at least said waiting time set value; and (g) upon detection of said count-up signal, responding to the network with an ISDN CONNECT message which indicates that the terminal is eligible to accept said incoming call, whereby a priority order for responding to the ISDN incoming call in the plurality of ISDN terminals is variable according to the predetermined calling party number.