Dynamic network automatic call distribution

• US 5,450,482 A
• Filed: 12/29/1992
• Issued: 09/12/1995
• Est. Priority Date: 12/29/1992
• Status: Expired due to Term

• Current Assignee: AT&T IPM Corp. (AT&T, Inc.)
• Original Assignee: AT&T Corporation (AT&T, Inc.)
• Inventors: Chen, Hsing-Tsuen, Parrish, Donald M. Jr., Sand, Paul R.
• Primary Examiner(s): Dwyer, James L.
• Assistant Examiner(s): Hunter, Daniel S.
• Application Number:
  US07/998,318
• Time in Patent Office: 987 Days
• Field of Search: 379/221, 379/266, 379/220, 379/265, 379/113, 379/219, 379/309, 379/225, 379/265, 379/207, 379/230, 379/229, 379/112
• US Class Current: 379/230
• CPC Class Codes: H04M 3/5237 Interconnection arrangements between ACD systems
• CPC Class Codes: H04Q 3/66 Traffic distributors

Abstract

A network ACD that, when one switch in the network has blocked services, distributes calls to another switch with available services; wherein such distribution is based on information stored in each switch. The stored information comprises a list of switches within the network wherein an availability status is associated with each service, and an availability status of a trunk connecting the initial switch and the other switches in the network. Each switch sends an updated status to the other switches via a signaling network whenever a service changes status.

Claims

1. A method for use in a distributed, network-based automatic call distribution (ACD) system, said ACD system comprising a plurality of network switching systems interconnected by trunks and by a signaling network, each of said plurality of switching systems offering a plurality of services, each of said plurality of switching systems maintaining a table of trunk availability between itself and other switches and each of said plurality of switching systems maintaining a table of service availability containing availability of the services offered at each of said plurality of switching systems, said method comprising the steps of:

when a threshold of availability of said services is reached at each of said plurality of switching systems, each of said plurality of switching systems informing the other of said plurality of switching systems by sending messages over said signaling network about the availability of services;

receiving a call for one of said services at a first of said plurality of switching systems;

in response to said first switching system determining that it cannot provide said service, said first switching system determining which one of said plurality of switching systems is available to provide said service by consulting said first switching system'"'"'s trunk availability table and service availability table to determine which of the other switching systems has both an available trunk connected to said first switching system and available services; and

distributing said call to said determined one of said other switching systems;

wherein said informing is controlled by comparing said message traffic to a message traffic threshold and not sending messages when said message traffic threshold is exceeded so that said signaling network is not flooded by messages.

2. A method according to claim 1 wherein said service availability table comprises a plurality of levels of availability, and wherein said step of determining which of said plurality of switching systems;

is available to provide said service includes determining which one of said plurality of switching systems has the highest level of availability.

3. A distributed, network-based automatic call distribution (ACD) system said ACD system comprising:

a plurality of switching systems interconnected by trunks and by signaling means for delivering messages among said switching systems, each of said plurality of switching systems offering a plurality of services, each of said plurality of switching systems including trunk availability means for storing an availability status of said trunks and service availability means for storing art availability status of services at each of said plurality of switching systems;

determining means at each of said plurality of switching systems responsive to receipt of a request for a service when said service is not available at that switching system for determining which of said plurality of switching systems is available to provide said service by consulting said trunk availability means and said service availability means to determine which of said switching systems has both an available interconnecting trunk and said service available, said determining means further comprising means for informing the other switching systems via said signaling means when a threshold of availability of said services is reached at said each of said switching systems and means for throttling message traffic by comparing said message traffic to a threshold of message traffic and not sending messages when said message traffic threshold is exceeded so that said signaling network is not flooded by messages; and

distribution means at each of said plurality of switching systems for distributing said call to said determined switching system.