Method and apparatus for queuing a call to the best split

• US 5,754,639 A
• Filed: 11/03/1995
• Issued: 05/19/1998
• Est. Priority Date: 11/03/1995
• Status: Expired due to Term

• Current Assignee: Avaya Incorporated
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Flockhart, Andrew Derek, Mathews, Eugene Paul
• Primary Examiner(s): Hunter, Daniel S.
• Assistant Examiner(s): Wolinsky, Scott
• Application Number:
  US08/552,642
• Time in Patent Office: 928 Days
• Field of Search: 379/265, 379/266, 379/309, 379/211, 379/212, 379/112, 379/219, 379/220, 379/221, 379/113, 370/412, 370/413, 370/415, 370/417
• US Class Current: 379/266.05
• CPC Class Codes: H04M 3/5232 Call distribution algorithms
• CPC Class Codes: H04M 3/5233 Operator skill based call distribution
• CPC Class Codes: H04M 3/5237 Interconnection arrangements between ACD systems
• CPC Class Codes: H04M 3/5238 with waiting time or load prediction arrangements
• CPC Class Codes: H04M 7/00 Arrangements for interconnection between switching centres

Abstract

A call-center ACD switch and queuing method are modified either to respond to an arriving call by determining, for those splits that could handle the call, the present values of a parameter that defines what is a best split for handling the call, determining from those present values which split is the best split for handling the call, and then enqueuing the call in the call queue of the best split, or to respond to a call that overflows the call queue of its primary agent split by determining which backup split in which call center is the best backup split for the call, and enqueuing the call in the call queue of the best backup split. Any desirable criteria may be used to determine the best split. A preferred criterion is queue waiting time: the best split is the one whose call queue offers the shortest in-queue waiting time. The waiting time may be either the real estimated waiting time (EWT), or the EWT weighted for other factors (WEWT) A programmable queuing control function directs the ACD switch to obtain, for each call, the EWTs of the splits, to weight these EWTs in order to obtain the corresponding WEWTs, to compare the WEWTs with each other in order to find the split with the shortest WEWT (the best split), and then to enqueue the call in the queue of this best split.

Claims

1. A call-distribution arrangement for a call-handling system that has, for each one of a plurality of calls, a plurality of call-handling facilities, comprising:

first means in each one of a plurality of the call-handling facilities, each responsive to receipt of a call by its call-handling facility for handling by the call-handling system, for determining for each one of the call'"'"'s plurality of call-handling facilities, the present value of a parameter predetermined to define what is a best call-handling facility;

second means in said each one call-handling facility, each responsive to a determination by its call-handling facility'"'"'s fist means, for evaluating the present values to determine the best one of the plurality of call-handling facilities for the call; and

third means in said each one call-handling facility, each responsive to a determination by its call handling facility'"'"'s second means of the best call-handling facility for the call, for directing the call to the best call-handling facility.

2. The arrangement of claim 1 wherein:

each call-handling facility comprises a different split of call-center agents.

3. The arrangement of claim 1 wherein:

each call-handling facility comprises a different call center.

4. The arrangement of claim 1 wherein:

each call-handling facility comprises a different split of call-center agents of a plurality of call centers.

5. The arrangement of claim 1 wherein:

the present values of the parameter indicate how expeditiously individual ones of the call-handling facilities will handle the call; and

each second means comprise

fourth means responsive to a determination by its call-handling facility'"'"'s first means of the present values of the parameter, for determining from the present values a call-handling facility that will handle the call most expeditiously, and

each third means comprise means responsive to a determination by its call-handling facility'"'"'s fourth means, for directing the call to the call-handling facility that will handle the call most expeditiously.

6. The arrangement of claim 1 wherein,

the present values of the parameter indicate periods of time in which each of said call-handling facilities are likely co handle the call;

and

each second means comprise

fourth means responsive to a determination by its call-handling facility'"'"'s first means of the present values of the parameter, for determining from the present values a call-handling facility for the call, from among the call'"'"'s plurality of call-handling facilities, which is likely to handle the call in a shortest period of time.

7. The arrangement of claim 1 wherein;

the present values of the parameter indicate periods of time in which each of said call-handling facilities are likely to handle the call; and

each means comprise

fourth means responsive to a determination by its call-handling facility'"'"'s fit means of the present values of the parameter, for determining from the present values a call-handling facility for the call, from among the call'"'"'s plurality of call-handling facilities, which is likely to handle the call in a shortest weighted period of time.

8. The arrangement of claim 1 wherein:

each call-handling facility has a corresponding call queue; and

each third means comprise

fourth means responsive to a determination by its call-handling facility'"'"'s second means of the best call-handling facility for the call, for enqueuing the call in the call queue of the best call-handling facility.

9. The arrangement of claim 8 wherein:

each first means comprise

fourth means for determining estimated waiting times of the call in the call queues of the call'"'"'s call-handling facilities; and

each second means comprise

means for determining a call-handling facility having a shortest estimated waiting time of the call in the corresponding call-queue, as the best call-handling facility.

10. The arrangement of claim 8 wherein:

each first means comprise

fourth means for determining weighted estimated waiting times of the call in the call queues of the call'"'"'s call-handling facilities, and

each second means comprise

means for determining a call-handling facility having a shortest weighted estimated waiting time of the call in the corresponding call queue, as the best call-handling facility.

11. A call-center system comprising:

a plurality of agent splits for handling calls, a plurality of said splits being splits for handling an individual call;

a plurality of call queues corresponding to different ones of the splits, each for holding calls for handling by the corresponding split;

at least one call center that includes the plurality of the agent splits and the plurality of the call queues;

first means in each said call center, each responsive to receipt of the individual call by its call center, for determining for each one of the splits for handling the individual call, the present value of a parameter predetermined to define what is a best split for handling the individual call;

second means in each said call center, each responsive to a determination by the first means of its call center, for evaluating the present values to determine the best split for handling the individual call; and

third means in each said call center, each responsive to a determination, by the second means of its call center, of the best split for handling the call, for effecting enqueuing of the individual call in the call queue of the best split.

12. The call-center system of claim 11 wherein:

the present values of the parameter indicate how expeditiously the splits for handling the individual call will handle the individual call;

each second means include means for determining which one of the splits for handling the individual call will handle the call most expeditiously; and

each third means comprise

fourth means responsive to a determination by the second means of its call center, for enqueuing the individual call in the call queue of the split that will handle the call most expeditiously.

13. The call-center system of claim 11 wherein:

each first means include

fourth means for determining whether facilities are available for connecting the individual call to an individual split for handling the call, and

each second means include

fifth means responsive to a determination that facilities are not available for connecting the individual call to the individual split for handling the call, for taking the individual split out of contention for being the best split for handling the individual call.

14. The call-center system of claim 11 wherein:

each first means include

fourth means for determining which ones of the splits for handling the individual call are presently unlikely to be a best split for handling the individual call; and

fifth means responsive to a determination by the fourth means of its call center, for determining the present values of the parameter of only the splits for handling the individual call other than said ones of the splits.

15. The call-center system of claim 11 wherein:

the present values of the parameter indicate estimated waiting times of the individual call in queues of the splits for handling the individual call; and

each second means comprise

fourth means for determining a split for handling the individual call which has a shortest estimated waiting time of the individual call in its corresponding call queue, as the best split.

16. The call-center system of claim 15 wherein:

each first means comprise

fifth means for determining an estimated waiting time of the individual call in the queue of a first split for handling the individual call, and responsive to the determined estimated waiting time of the individual call in the queue of the first split being more than a predetermined amount of time, for determining an estimated waiting time of the individual call in the queue of a second split for handling the individual call;

each fourth means comprise

sixth means responsive to the determined estimated waiting times of the individual call in the queues of both the first and the second splits being more than the predetermined amount of time, for determining which one of the first and the second splits has a shortest determined estimated waiting time of the individual call in its corresponding call queue; and

each third means comprise

seventh means responsive to the estimated waiting times of the individual call in the queue of an individual split being no more than the predetermined amount of time, for enqueuing the individual call in the call queue of the individual split, and responsive to the determined estimated waiting times of the individual call in the queues of both the first and the second splits being more than the predetermined amount of time, for enqueuing the individual call in the call queue of the split determined by the sixth means of its call center to have the shortest determined estimated waiting time.

17. The call-center system of claim 16 wherein:

the sixth means of an individual call center determine the second split to have the shortest determined estimated waiting time;

the first means of the individual call center further comprise

eighth means for timing a time interval,

ninth means responsive to the determination by the sixth means of the individual call center, for causing the eighth means of the individual call center to begin timing a first time interval, and

the fifth means of the individual call center are responsive to receipt of a second individual call b the individual call center when the eighth means of the individual call center have not completed timing the first time interval, for skipping a determining of an estimated waiting time of the second individual call in the queue of the first split and determining an estimated waiting time of the second individual call in the queue of the second split, are responsive to the receipt of the second individual call by the individual call center when the eighth means of the individual call center have completed timing the first time interval, for determining an estimated waiting time of the second individual call in the queue of the first split, and are responsive to the determined estimated waiting time of the second individual call in tie queue of the first split being more than a predetermined amount of time, for determining the estimated waiting time of the second individual call in the queue of the second split.

18. The call-center system of claim 11 wherein:

the present values of the parameter indicate weighted estimated waiting times of the individual call in queues of the splits for handling the individual call; and

each second means comprise

fourth means for determining a split for handling the individual call which has a shortest weighted estimated waiting time of the individual call in its corresponding call queue, as the best split.

19. The call-center system of claim 18 wherein:

each first means comprise

fifth means for determining an estimated waiting time of the individual call in the queue of a first split for handling the individual call, and responsive to the determined estimated waiting time of the individual call in the queue of the first split being more than a predetermined amount of time, for determining an estimated waiting time of the individual call in the queue of a second split for handling the individual call;

each fourth means comprise

sixth means responsive to the estimated waiting time of the individual call in the queue of a predetermined split being more than the predetermined amount of time, for incrementing the estimated waiting time in the queue of the predetermined split by a predetermined amount to obtain a weighted estimated waiting time in the queue of the predetermined split, and

seventh means responsive to the determined estimated waiting times of the individual call in the queues of both the first and the second splits being more than the predetermined amount of time, for determining which one of the first and the second splits has a shortest weighted estimated waiting time of the individual call in its corresponding call queue; and

each third means comprise

eighth means responsive to the estimated waiting times of the individual call in the queue of an individual split being no more than a predetermined amount of time, for enqueuing the individual call in the call queue of the individual split, and responsive to the estimated waiting times of the individual call in the queues of both the first and the second splits being more than the predetermined amount of time, for enqueuing the individual call in the call queue of the split determined by the seventh means of its call center to have the shortest weighted estimated waiting time.

20. The call center of claim 19 wherein:

the seventh means of an individual call center determine the second split to have the shortest weighted estimated waiting time;

the first means of the individual call center further comprise

ninth means for timing a time interval,

tenth means responsive to the determination by the seventh means of the individual call center, for causing the ninth means of the individual call center to begin timing a first time interval, and

the fifth means of the individual call center am responsive to receipt of a second individual call by the individual call center when the ninth means of the individual call center have not completed timing the first time interval, for skipping a determining of an estimated waiting time of the second individual call in the queue of the first split and determining an estimated waiting tine of the second individual call in the queue of the second split, are responsive to the receipt of the second individual call by the individual call center when the ninth means of the individual call center have completed timing the first time interval, for determining an estimated waiting time of the second individual call in the queue of the first split, and are responsive to the determined estimated waiting time of the second individual call in the queue of the first split being more than a predetermined amount of time, for determining the estimated waiting time of the second individual call in the queue of the second split.

21. A method of distributing calls in a call-handling system that has, for each one of a plurality of calls, a plurality of call-handling facilities, comprising the steps of:

in response to receipt of a call by me one of a plurality of the call-handling facilities for handling by the call-handling system, the receiving handling facility determining, for each one of the cell'"'"'s plurality of call-handling facilities, the present value of a parameter predetermined to define what is a best call-handling facility;

the receiving call-handling facility evaluating said present values to determine a best call-handling facility for the call from among the call'"'"'s plurality of call-handling facilities; and

in response to a determination of the best call-handling facility, the receiving call-handling facility directing the call to the best call-handling facility.

22. The method of claim 21 for a call-handling system wherein each call-handling facility comprises a different split of call-center agents.

23. The method of claim 21 for a call-handling system wherein each call-handling facility comprises a different call center.

24. The method of claim 21 for a call-handling system wherein each call-handling facility comprises a different split of call-center agents of a plurality of call centers.

25. The method of claim 21 wherein:

the present values of the parameter indicate how expeditiously individual ones of the call-handling facilities will handle the call; and

the step of evaluating said present values to determine a best call-handling facility comprises the step of

in response to a determination of the present values of the parameter, the receiving call-handling facility determining from the present values a call-handling facility that will handle the call most expeditiously; and

the step of directing the call to the best call-handling facility comprises the step of

in response to a determination of which one of the call-handling facilities will handle the call most expeditiously, the receiving call-handling facility directing the call to the call-handling facility that will handle the call most expeditiously.

26. The method of claim 21 wherein:

the present values of the parameter indicate periods of time in which each of said call-handling facilities are likely to handle the call; and

the step of evaluating said present values to determine a best call-handling facility comprises the step of

in response to a determination of the present values of the parameter, the receiving call-handling facility determining from the present values a call-handling facility for the call, from among the call'"'"'s plurality of call-handling facilities, which is likely to handle the call in a shortest period of time.

27. The method of claim 21 wherein:

the present values of the parameter indicate periods of time in which each of said call-handling facilities are likely to handle the call; and

the step of evaluating said present values to determine a best-call handling facility comprises the step of

in response to a determination of the present values of the parameter, the receiving call-handling facility determining from the present values a call-handling facility for the call, from among the call'"'"'s plurality of call-handling facilities, which is likely to handle the call in a shortest weighted period of time.

28. The method of claim 21 for a call-handling system wherein each call-handling facility has a corresponding call queue, wherein:

the step of directing comprises the step of

in response to a determination of the best call-handling facility for handling the call, enqueuing the call in the call queue of the best call-handling facility.

29. The method of claim 28 wherein:

the step of determining present values of a parameter comprises the step of

the receiving call-handling facility determining estimated waiting times of the call in the call queues of the call'"'"'s call-handling facilities; and

the step of evaluating said present values to determine a best call-handling facility for the call comprises the step of

the receiving call-handling facility determining a call-handling facility having a shortest estimated waiting time of the call in the corresponding call queue, as the best call-handling facility.

30. The method of claim 28 wherein:

the step of determining present values of a parameter comprises the step of

the receiving call-handling facility determining weighted estimated waiting times of the call in the call queues of the call'"'"'s call-handling facilities; and

the step of evaluating said present values to determine a best call-handling facility for the call comprises the step of

the receiving call-handling facility determining a call-handling facility having a shortest weighted estimated waiting time of the call in the corresponding call queue, as the best call-handling facility.

31. A method of distributing arriving calls in a call-center system comprising a plurality of first agent splits for handling calls, a plurality of said first agent splits being second agent splits for handling an individual call, a plurality of call queues each corresponding to a different one of the first agent splits, each for holding calls for handling by the corresponding first agent split, and at least one call center that includes the plurality of first agent splits and the plurality of call queues, the method comprising the steps of:

in response to receipt of the individual call by a call center, the receiving call center determining for each one of the second agent splits, the present value of a parameter predetermined to define what is a best split for handling the individual call;

in response to a determination by the receiving call center of the present values, the receiving call center evaluating the present values to determine the best second split for handling the individual call; and

in response to a determination by the receiving call center of the best second split for handling the call, the receiving call center effecting enqueuing of the individual call in the call queue of the best second split.

32. The method of claim 31 wherein:

the present values of the parameter indicate how expeditiously the second splits will handle the individual call;

the step of evaluating the present values to determine the best second split for handling the individual call comprises the step of

in response to a determination by the receiving call center of the present values of the parameter, the receiving call center determining which one of the second splits will handle the call most expeditiously; and

the step of effecting enqueuing comprises the step of

in response to a determination by the receiving call center of the second it that will handle the call most expeditiously, the receiving call center effecting queuing of the individual call in the call queue of the second split that will handle call most expeditiously.

33. The method of claim 31 wherein:

the step of determining the present value of the parameter for each second split comprises the steps of

determining whether facilities are available for connecting the individual call to an individual second split, and

in response to a determination that facilities am not available for connecting the individual call to the individual second split, taking the individual second split out of contention for being the best second split for handling the individual call.

34. The method of claim 31 wherein:

the step of determining the present value of the parameter for each second split comprises the steps of

determining which ones of the second splits are presently unlikely to be a best second split for handling the individual call, and

in response to a determination of which ones of the second splits are presently unlikely to be a best second split for handling the individual call, determining the present values of the parameter of only the second splits other than said ones of the second splits.

35. The method of claim 31 wherein:

the present values of the parameter indicate estimated waiting times of the individual call in queues of the second splits; and

the step of determining the present value of the parameter for each second split comprises the step of

determining a second split which has a shortest estimated waiting time of the individual call in its corresponding call queue, as the best second split.

36. The method of claim 35 wherein:

the step of determining a second split which has a shortest estimated waiting time of the individual call in its corresponding call queue, as the best second split, comprises the steps of

determining an estimated waiting time of the individual call in the call queue of an individual one of the second splits and

in response to the determined estimated waiting time of the individual call in the queue of the individual one of the second slits being more than a predetermined amount of time, determining an estimated waiting time of the individual call in the queue of another one of the second splits;

the step of determining a second split which has a shortest estimated waiting time of the individual call in its corresponding call queue, as the best second split, comprises the step of

in response to the determined estimated waiting times of the individual call in the queues of both the individual and the other one of the second splits being more than the predetermined amount of time, determining which one of the individual and the other one of the second splits has a shortest determined estimated waiting time of the individual call in its corresponding call queue; and

the step of effecting enqueuing comprises the steps of

in response to the estimated waiting time of the individual call in the queue of an individual one of the second splits being no more than a redetermined amount of time, enqueuing the individual call in the call queue of the individual one of the second splits, and

in response to the determined estimated waiting times of the individual call in the queues of both the individual and the other one of the second splits being more than the predetermined amount of time, enqueuing the individual call in the call queue of the one of the second splits determined to have the shortest determined estimated waiting time.

37. The method of claim 36 wherein

the step of determining which one of the individual and the other one of the second splits has the shortest determined estimated waiting time determines that the other one of the second has the shortest determined estimated waiting time, and

the method further comprises the steps of:

in response to the determination that the other one of the second its has the shortest determined estimated waiting time, beginning to time a first interval;

in response to receipt by the receiving call center of a second individual call when timing of the first time interval has not been completed, skipping a determining of an estimated waiting time of the second individual call in the queue of the individual one of the second splits and determining an estimated waiting time of the second individual call in the queue of the other one of the second splits;

in response to the receipt of the second individual call when the timing of the first time interval has been completed, determining an estimated waiting time of the second individual call in the queue of the individual one of the second splits; and

in response to the determined estimated waiting time of the second individual call in the queue of the individual one of the second splits being more than a predetermined amount of time, determining the estimated waiting time of the second individual call in the queue of the other one of the second splits.

38. The method of claim 31 wherein:

the present values of the parameter indicate weighted estimated waiting times of the individual call in queues of the second splits; and

the step of evaluating the present values to determine the best second split for handling the call comprises the step of

determining a second split for handling the individual call which has a shortest weighted estimated waiting rime of the individual call in its corresponding call queue, as the best second split.

39. The method of claim 38 wherein:

the step of determining the present values of the parameter comprises steps of

determining an estimated waiting time of the individual call in the queue of an individual one of the second splits, and

in response to the determined estimated waiting time of the individual in the queue of the individual one of the second being more than a predetermined amount of time, determining an estimated waiting time of the individual call in the queue of another one of the second splits;

the step of determining a second split which has a shortest weighted estimated waiting time comprises the steps of

in response to the estimated waiting time of the individual call in the queue of the individual or the other one of the second splits being more than the predetermined amount of time, incrementing the estimated waiting time in the queue of the individual or the other one of the second splits by a predetermined amount to obtain a weighted estimated waiting time in the queue of the individual or the other one of the second splits, and

in response to the determined estimated waiting times of the individual call in the queues of both the individual and the other one of the second splits being more than the predetermined amount of time, determining which one of the individual and the other one of the second splits has a shortest weighted estimated waiting time of the individual call in its corresponding call queue; and

the step of effecting enqueuing comprises the steps of

in response to Me estimated waiting time of the individual call in the queue of the individual or the other one of the second splits being determined to be no more than a predetermined amount of time, enqueuing the individual call in the call queue of the individual or the other one of the second splits, and

in response to the estimated waiting times of the individual call in the queues of both the individual and the other one of the second splits being more an the predetermined amount of time, enqueuing the individual call in the call queue of the individual or the other one of the second slits determined to have the shortest weighted estimated waiting time.

40. The method of claim 39 wherein

the step of determining which one of the individual and the other one of the second splits has the shortest weighted estimated waiting time determines that the other one of the second splits has the shortest weighted estimated waiting time, and

the method further comprises the steps of:

in response to the determination that the other one of the second splits has the shortest weighted estimated waiting time, beginning to time a first time interval;

in response to receipt of a second individual call by the receiving call center when timing of the first time interval has not been completed, skipping a determining of an estimated waiting time of the second individual call in the queue of the individual one of the second splits and determining an estimated waiting time of the second individual call in the queue of the other one of the second splits;

in response to the receipt of the second individual call when the timing of the first time interval has been completed, determining an estimated waiting time of the second individual call in the queue of the individual one of the second splits; and

in response to the determined estimated waiting time of the second individual call in the queue of the individual one of the second splits being more than a predetermined amount of time, determining the estimated waiting time of the second individual call in the queue of the other one of the second splits.