Call agents and systems and methods for providing emergency call services on heterogeneous networks

A method for providing emergency call service on a cable telephony system having an in-band control architecture, the method comprising the steps of:

• detecting an off-hook signal from a user;
• transmitting a service request to the cable telephony system responsive to the detected off-hook condition;
• receiving a request to provide a dial tone to the user from the cable telephony system responsive to the transmitted service request;
• providing a dial tone to the user responsive to the request to provide a dial tone;
• receiving a number associated with the emergency call service from the user;
• providing the received number associated with the emergency call service to the cable telephony system;
• receiving an allocation of a portion of the bandwidth of the cable telephony system which is not allocated to telephony from the cable telephony system;
• and
• transmitting the received number to a telephone switch using the received allocation of a portion of the bandwidth of the cable telephony system to initiate the emergency call service.

A method for providing emergency call service on a cable telephony system having an in-band control architecture, the method comprising the steps of:

• receiving a service request from a user station;
• determining if a portion of the bandwidth of a cable system which is allocated to the cable telephony system is fully utilized;
• transmitting a request to provide a dial tone to the user station responsive to the received service request regardless of whether the portion of the bandwidth of the cable system which is allocated to the cable telephony system is fully utilized;
• receiving a number associated with the service request from the user station;
• determining if the received number is an emergency call number associated with the emergency call service;
• allocating a portion of the bandwidth of the cable system which is not allocated to the cable telephony to the service request if the received number is an emergency call number associated with the emergency call service and the portion of the bandwidth of the cable system which is allocated to the cable telephony system is fully utilized;
• establishing a connection between the user station and a telephone switch using the allocated portion of the bandwidth of the cable system;
• transmitting a request to the user station requesting transmission of the received number to the telephone switch using the allocated portion of the bandwidth of the cable system;
• and
• transmitting a request to provide a busy signal to the user station if the received number is not an emergency call number associated with the emergency call service and the portion of the bandwidth of the cable system which is allocated to the cable telephony system is fully utilized.

A method for providing emergency call service on a cable telephony system having an in-band control architecture, the method comprising the steps of:

• receiving a service request from a user station;
• determining if a portion of the bandwidth of a cable system which is allocated to the cable telephony system is fully utilized;
• transmitting a request to provide a dial tone to the user station responsive to the received service request regardless of whether the portion of the bandwidth of the cable system which is allocated to the cable telephony system is fully utilized;
• receiving a number associated with the service request from the user station;
• determining if the received number is an emergency call number associated with the emergency call service;
• pre-empting a part of the portion of the bandwidth of the cable system which is allocated to telephony if the received number is an emergency call number associated with the emergency call service and the portion of the bandwidth of the cable system which is allocated to the cable telephony system is fully utilized;
• establishing a connection between the user station and a telephone switch using the pre-empted part of the portion of the bandwidth of the cable system;
• transmitting a request to the user station requesting transmission of the received number to the telephone switch using the preempted part of the portion of the bandwidth of the cable system;
• and
• transmitting a request to provide a busy signal to the user station if the received number is not an emergency call number associated with the emergency call service and the portion of the bandwidth of the cable system which is allocated to the cable telephony system is fully utilized.

A call agent for a cable system having a bandwidth, the call agent comprising:

• a media terminal adapter (MTA) control circuit that receives in-band control signals from a MTA and provides in-band control signals to the MTA, the control signals from the MTA including a request for telephony service and an associated service identifier, the MTA control circuit being configured to determine if a received request for telephony service is a request for emergency service based on the associated service identifier;
• a bandwidth control circuit that determines if a portion of the bandwidth of the cable system which is allocated to telephony is fully utilized;
• and
• a call setup circuit that obtains a portion of the bandwidth of the cable system to provide the requested telephony service if the request for telephony service is a request for emergency service and the portion of the bandwidth of the cable system which is allocated to telephony is fully utilized, the call setup circuit being configured to establish a connection between the MTA and a telephone switch to support the requested emergency service using the obtained portion of the bandwidth of the cable system.

A system for providing emergency service on a heterogeneous network comprising a public switched telephone network (PSTN) and a packet based network to a local user, the packet based network to the local user having a bandwidth, the system comprising:

• means for receiving a request for telephony service wherein the telephony service will be provided over the packet based network;
• means for determining if a portion of the bandwidth of the packet based network which is allocated to telephony is fully utilized;
• means for determining if the request for telephony service is a request for emergency service;
• means for obtaining a portion of the bandwidth of the packet based network to provide the requested telephony service if the request for telephony service is a request for emergency service and the portion of the bandwidth of the packet based network which is allocated to telephony is fully utilized;
• and
• means for providing the requested emergency service using the obtained portion of the bandwidth of the packet based network.

A system for providing emergency call service on a cable telephony system having an in-band control architecture, the system comprising:

• means for detecting an off-hook signal from a user;
• means for transmitting a service request to the cable telephony system responsive to the detected off-hook condition;
• means for receiving a request to provide a dial tone to the user from the cable telephony system responsive to the transmitted service request;
• means for providing a dial tone to the user responsive to the request to provide a dial tone;
• means for receiving a number associated with the emergency call service from the user;
• means for providing the received number associated with the emergency call service to the cable telephony system;
• means for receiving an allocation of a portion of the bandwidth of the cable telephony system which is not allocated to telephony from the cable telephony system;
• and
• means for transmitting the received number to a telephone switch using the received allocation of a portion of the bandwidth of the cable telephony system to initiate the emergency call service.

A system for providing emergency call service on a cable telephony system having an in-band control architecture, the system comprising:

• means for receiving a service request from a user station;
• means for determining if a portion of the bandwidth of a cable system which is allocated to the cable telephony system is fully utilized;
• means for transmitting a request to provide a dial tone to the user station responsive to the received service request regardless of whether the portion of the bandwidth of the cable system which is allocated to the cable telephony system is fully utilized;
• means for receiving a number associated with the service request from the user station;
• means for determining if the received number is an emergency call number associated with the emergency call service;
• means for allocating a portion of the bandwidth of the cable system which is not allocated to the cable telephony to the service request if the received number is an emergency call number associated with the emergency call service and the portion of the bandwidth of the cable system which is allocated to the cable telephony system is fully utilized;
• means for establishing a connection between the user station and a telephone switch using the allocated portion of the bandwidth of the cable system;
• means for transmitting a request to the user station requesting transmission of the received number to the telephone switch using the allocated portion of the bandwidth of the cable system;
• and
• means for transmitting a request to provide a busy signal to the user station if the received number is not an emergency call number associated with the emergency call service and the portion of the bandwidth of the cable system which is allocated to the cable telephony system is fully utilized.

A system for providing emergency call service on a cable telephony system having an in-band control architecture, the system comprising:

• means for receiving a service request from a user station;
• means for determining if a portion of the bandwidth of a cable system which is allocated to the cable telephony system is fully utilized;
• means for transmitting a request to provide a dial tone to the user station responsive to the received service request regardless of whether the portion of the bandwidth of the cable system which is allocated to the cable telephony system is fully utilized;
• means for receiving a number associated with the service request from the user station;
• means for determining if the received number is an emergency call number associated with the emergency call service;
• means for preempting a part of the portion of the bandwidth of the cable system which is allocated to telephony if the received number is an emergency call number associated with the emergency call service and the portion of the bandwidth of the cable system which is allocated to the cable telephony system is fully utilized;
• means for establishing a connection between the user station and a telephone switch using the preempted part of the portion of the bandwidth of the cable system;
• means for transmitting a request to the user station requesting transmission of the received number to the telephone switch using the preempted part of the portion of the bandwidth of the cable system;
• and
• means for transmitting a request to provide a busy signal to the user station if the received number is not an emergency call number associated with the emergency call service and the portion of the bandwidth of the cable system which is allocated to the cable telephony system is fully utilized.