Method and apparatus for queuing a call to the best backup split

• US 5,740,238 A
• Filed: 11/03/1995
• Issued: 04/14/1998
• Est. Priority Date: 11/03/1995
• Status: Expired due to Term

• Current Assignee: Avaya Incorporated
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Mathews, Eugene Paul, Flockhart, Andrew Derek
• Primary Examiner(s): Zele, Krista
• Assistant Examiner(s): Wolinsky, Scott
• Application Number:
  US08/552,641
• Time in Patent Office: 893 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 3/5233 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

Abstract

A call-center ACD switch and queuing method are modified either 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, or 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. Any desirable criteria may be used to determine the best split or the best back-up split. A preferred criterion is queue waiting time: the best split or the best backup 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 overflow call, the EWTs of its backup splits, to weight these EWTs in order to obtain the corresponding WEWTs, to compare the WEWTs with each other in order to find the backup split with the shortest WEWT (the best backup split), and then to enqueue the call in the queue of this best backup split.

Claims

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

first means responsive to an inability of a call'"'"'s primary call-handling facility to expeditiously handle the call, for determining which one of considered ones of the plurality of backup call-handling facilities for the call will handle the call most expeditiously; and

second means responsive to a determination by the first means, for directing the call to the considered backup call-handling facility that will handle the call most expeditiously.

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 first means comprise

third means responsive to receipt of the call, for determining that the call'"'"'s primary call-handling facility is not likely to handle the call in an acceptable period of time, and

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

6. The arrangement of claim 1 wherein:

the first means comprise

third means responsive to receipt of the call, for determining that the call'"'"'s primary call-handling facility is not likely to handle the call in an acceptable period of time, and

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

7. The arrangement of claim 1 wherein:

each call-handling facility has a corresponding call queue;

the first means comprise

third means responsive to the call overflowing the call queue of the primary call-handling facility, for determining a best backup call-handling facility for the call; and

the second means comprise

fourth means responsive to a determination by the third means, for enqueuing the call in the call queue of the best backup call-handling facility.

8. The arrangement of claim 7 wherein:

the third means comprise

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

9. The arrangement of claim 7 wherein:

the third means comprise

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

10. A call-center system comprising:

a plurality of agent splits for handling calls, one of the splits being a primary split for handling an individual call and a plurality of others of the splits being backup splits for handling the individual call;

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

first means responsive to the individual call overflowing the call queue of the primary split, for determining which one of considered ones of the backup splits for the individual call will handle the individual call most expeditiously; and

second means responsive to a determination by the first means, for enqueuing the individual call in the call queue of the considered backup split that will handle the individual call most expeditiously.

11. The call-center system of claim 10 wherein:

the first means include

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

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

12. The call-center system of claim 10 wherein:

the first means include

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

means for determining a best backup split for the individual call from among the backup splits other than said ones of the backup splits.

13. The call-center system of claim 10 wherein:

the first means comprise

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

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

the third means comprise

fourth means for determining an estimated waiting time of the individual call in the queue of a first backup split, and responsive to the determined estimated waiting time of the individual call in the queue of the first backup 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 backup split, and

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

the second means comprise

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

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

the fifth means determine the second backup split to have the shortest determined estimated waiting time;

the third means further comprise

seventh means for timing a time interval, and

eighth means responsive to the determination by the fifth means, for causing the seventh means to begin timing a first time interval; and

the fourth means are responsive to a second individual call overflowing the call queue of the primary split when the seventh means 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 backup split and determining an estimated waiting time of the second individual call in the queue of the second backup split, and are responsive to the second individual call overflowing the call queue of the primary split when the seventh means have completed timing the first time interval, for determining an estimated waiting time of the second individual call in the queue of the first backup split, and are responsive to the determined estimated waiting time of the second individual call in the queue of the first backup 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 backup split.

16. The call-center system of claim 10 wherein:

the first means comprise

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

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

the third means comprise

fourth means for determining an estimated waiting time of the individual call in the queue of a first backup split, and responsive to the determined estimated waiting time of the individual call in the queue of the first backup 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 backup split,

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

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

the second means comprise

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

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

the sixth means determine the second backup split to have the shortest weighted estimated waiting time;

the third means further comprise

eighth means for timing a time interval, and

ninth means responsive to the determination by the sixth means, for causing the eighth means to begin timing a first time interval; and

the fourth means are responsive to a second individual call overflowing the call queue of the primary split when the eighth means 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 backup split and determining an estimated waiting time of the second individual call in the queue of the second backup split, and are responsive to the second individual call overflowing the call queue of the primary split when the eighth means have completed timing the first time interval, for determining an estimated waiting time of the second individual call in the queue of the first backup split, and are responsive to the determined estimated waiting time of the second individual call in the queue of the first backup 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 backup split.

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

in response to an inability of a call'"'"'s primary call-handling facility to expeditiously handle the call, determining which one of considered ones of the plurality of backup call-handling facilities for the call will handle the call most expeditiously; and

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

20. The method of claim 19 for a call-handling system wherein each call-handling facility comprises a different split of call-center agents.

21. The method of claim 19 for a call-handling system wherein each call-handling facility comprises a different call center.

22. The method of claim 19 for a call-handling system wherein each call-handling facility comprises a different split of call-center agents of a plurality of call centers.

23. The method of claim 19 wherein:

the step of determining comprises the steps of

in response to receipt of the call, determining that the call'"'"'s primary call-handling facility is not likely to handle the call in an acceptable period of time, and

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

24. The method of claim 19 wherein:

the step of determining comprises the steps of

in response to receipt of the call, determining that the call'"'"'s primary call-handling facility is not likely to handle the call in an acceptable period of time, and

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

25. The method of claim 19 for a call-handling system wherein each call-handling facility has a corresponding call queue, wherein:

the step of determining comprises the step of

in response to the call overflowing the call queue of the primary call-handling facility, determining a best backup call-handling facility for the call; and

the step of directing comprises the step of

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

26. The method of claim 25 wherein:

the step of determining the best backup call-handling facility for the call in response to the call overflowing the call queue of the primary call-handling facility comprises the step of

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

27. The method of claim 25 wherein:

the step of determining the best backup call-handling facility for the call in response to the call overflowing the call queue of the primary call-handling facility comprises the step of

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

28. A method of distributing overflow calls in a call-center system comprising a plurality of agent splits for handling calls, one of the splits being a primary split for handling an individual call and a plurality of others of the splits being backup splits for handling the individual call, and a plurality of call queues each corresponding to a different one of the splits, each for holding calls for handling by the corresponding split, the method comprising the steps of:

in response to the individual call overflowing the call queue of the primary split, determining which one of considered ones of the backup splits for the individual call will handle the individual call most expeditiously; and

in response to a determination of the backup split that will handle the individual call most expeditiously, enqueuing the individual call in the call queue of the considered backup split that will handle the individual call most expeditiously.

29. The method of claim 28 wherein:

the step of determining comprises the steps of

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

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

30. The method of claim 28 wherein:

the step of determining comprises the steps of

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

determining a best backup split for the individual call from among the backup splits other than said ones of the backup splits.

31. The method of claim 28 wherein:

the step of determining comprises the step of

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

32. The method of claim 31 wherein:

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

determining an estimated waiting time of the individual call in the queue of a first backup split,

in response to the determined estimated waiting time of the individual call in the queue of the first backup split being more than a predetermined amount of time, determining an estimated waiting time of the individual call in the queue of a second backup split, and

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

the step of enqueuing comprises the steps of

in response to the estimated waiting time of the individual call in the queue of an individual backup split being determined to be no more than a predetermined amount of time, enqueuing the individual call in the call queue of the individual backup split, and

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

33. The method of claim 32 wherein

the step of determining which one of the first and the second backup splits has the shortest determined estimated waiting time determines that the second backup split has the shortest determined estimated waiting time, and

the method further comprises the steps of:

in response to the determination that the second backup split has the shortest determined estimated waiting time, beginning to time a first time interval;

in response to a second individual call overflowing the call queue of the primary split 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 first backup split and determining an estimated waiting time of the second individual call in the queue of the second backup split;

in response to the second individual call overflowing the call queue of the primary split 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 first backup split; and

in response to the determined estimated waiting time of the second individual call in the queue of the first backup split being more than a predetermined amount of time, determining the estimated waiting time of the second individual call in the queue of the second backup split.

34. The method of claim 28 wherein:

the step of determining comprises the step of

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

35. The method of claim 34 wherein:

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

determining an estimated waiting time of the individual call in the queue of a first backup split,

in response to the determined estimated waiting time of the individual call in the queue of the first backup split being more than a predetermined amount of time, determining an estimated waiting time of the individual call in the queue of a second backup split,

in response to the estimated waiting time of the individual call in the queue of a predetermined backup split being determined to be more than the predetermined amount of time, incrementing the estimated waiting time in the queue of the predetermined backup split by a predetermined amount to obtain a weighted estimated waiting time in the queue of the predetermined backup split, and

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

the step of enqueuing comprises the steps of

in response to the estimated waiting time of the individual call in the queue of an individual backup split being determined to be no more than a predetermined amount of time, enqueuing the individual call in the call queue of the individual backup split, and

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

36. The method of claim 35 wherein

the step of determining which one of the first and the second backup splits has the shortest weighted estimated waiting time determines that the second backup split has the shortest weighted estimated waiting time, and

the method further comprises the steps of:

in response to the determination that the second backup split has the shortest weighted estimated waiting time, beginning to time a first time interval;

in response to a second individual call overflowing the call queue of the primary split when timing of the first time interval has been completed, skipping a determining of an estimated waiting time of the second individual call in the queue of the first backup split and determining an estimated waiting time of the second individual call in the queue of the second backup split;

in response to the second individual call overflowing the call queue of the primary split 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 first backup split; and

in response to the determined estimated waiting time of the second individual call in the queue of the first backup split being more than a predetermined amount of time, determining the estimated waiting time of the second individual call in the queue of the second backup split.