Telecommunication switch having a universal API with a single call processing message including user-definable data and response message each having a generic format

• US 6,134,618 A
• Filed: 03/26/1999
• Issued: 10/17/2000
• Est. Priority Date: 11/30/1995
• Status: Expired due to Term

• Current Assignee: Excel Switching Corp. (Enghouse Systems Limited)
• Original Assignee: Excel Switching Corp. (Enghouse Systems Limited)
• Inventors: Hebert, Mark P.
• Primary Examiner(s): Lee, Thomas C.
• Assistant Examiner(s): NGUYEN, TANH Q
• Application Number:
  US09/277,469
• Time in Patent Office: 571 Days
• Field of Search: 709/300, 709/302, 709/230, 710/15, 710/19, 710/62, 710/63, 710/105, 710/129, 710/131, 710/52, 710/72, 370/469, 370/465, 370/466, 370/467, 370/471, 370/473, 370/474, 379/269, 379/93, 379/94, 395/680, 395/682, 395/835, 395/839, 395/882, 395/883, 395/309, 395/311, 395/285, 395/200.61, 395/872, 395/892, 395/200.6
• US Class Current: 710/105
• CPC Class Codes: H04L 69/03 Protocol definition or specification protocol conformance testing H04L1/244
• CPC Class Codes: H04L 69/12 Protocol engines
• CPC Class Codes: H04L 69/32 Architecture of open systems interconnection [OSI] 7-layer type protocol stacks, e.g. the interfaces between the data link level and the physical level
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04Q 11/0414 Details
• CPC Class Codes: H04Q 2213/13003 Constructional details of switching devices
• CPC Class Codes: H04Q 2213/13034 A/D conversion, code compression/expansion
• CPC Class Codes: H04Q 2213/1305 Software aspects
• CPC Class Codes: H04Q 2213/13056 Routines, finite state machines
• CPC Class Codes: H04Q 2213/1309 Apparatus individually associated with a subscriber line, line circuits
• CPC Class Codes: H04Q 2213/13093 Personal computer, PC
• CPC Class Codes: H04Q 2213/13096 Digital apparatus individually associated with a subscriber line, digital line circuits
• CPC Class Codes: H04Q 2213/13103 Memory
• CPC Class Codes: H04Q 2213/13106 Microprocessor, CPU
• CPC Class Codes: H04Q 2213/13176 Common channel signaling, CCS7
• CPC Class Codes: H04Q 2213/13204 Protocols
• CPC Class Codes: H04Q 2213/13216 Code signals, frame structure
• CPC Class Codes: H04Q 2213/1322 PBX
• CPC Class Codes: H04Q 2213/13299 Bus
• CPC Class Codes: H04Q 2213/1332 Logic circuits
• CPC Class Codes: H04Q 2213/1334 : Configuration within the switch
• CPC Class Codes: H04Q 2213/13405 : Dual frequency signaling, DTMF
• CPC Class Codes: H04Q 3/542 : Logic circuits or arrangements therefor
• CPC Class Codes: H04Q 3/54583 : Software development, e.g. procedural, object oriented, software generation, software testing
• CPC Class Codes: H04Q 3/625 : Arrangements in the private branch exchange

Abstract

The present invention is a universal host-to-switch application program interface (API) utilizing a generic message format for performing call control processing and capable of being customized to meet telecommunications application and network signalling protocol requirements. The generic message formats have programmable fields for transmitting commands, status, and data between the host application and the switch. The present invention further comprises a programmable telecommunication switch that provides a user with the ability to define a desired signalling protocol, either "standard" or custom in nature, for performing any desired switching functions. The present invention includes a protocol development environment which enables a user to define a separate finite state machine for each port provided by the switch. Each finite state machine may be independently defined by combining a series of elementary processing steps, called atomic functions, into primitives, which are in turn combined with states and events to define the desired state machine. Such state machines may include atomic functions configured to generate predetermined messages under predetermined conditions and containing predetermined information. Such state machines may further include the ability to respond to state events that include the receipt of generic API messages configured to provide the state machine with information from the host application.

Claims

1. A functionally-layered programmable telecommunications switch having a host associated therewith said telecommunications switch comprising:

controllable-switching means for dynamically connecting or disconnecting communication paths between various ones of a plurality of channels in response to messages generated by a telecommunications services application;

one or more instantiations of a plurality of programmable protocol language (PPL) component state machines, each of which is associated with a PPL component of said telecommunications switch and each said instantiation represents one of a plurality of protocols configured to perform call processing functions with respect to said plurality of channels, wherein said plurality of PPL component state machines are functionally associated with the functional layers of the telecommunications switch including said PPL components;

each of said plurality of PPL component state machines comprising (i) one or more libraries each containing one or more predetermined functions having associated therewith user-specified data, (ii) one or more predetermined logical states which may be user-definable, (iii) at least one predetermined event associated with each said one or more predetermined logical states each said at least one predetermined event uniquely identified relative to each of said plurality of PPI, component state machines, wherein upon an occurrence of one of said at least one predetermined event, a user-definable, predetermined primitive associated with the occurring event is invoked, said primitive comprising a predetermined series of one or more of said predetermined functions; and

a programmable universal applications program interface (API) for transferring standardized user-programmable messages having a generic message format among said functional layers, and between said functional layers and said telecommunications services application, including a first message type having user-programmable functionality for transferring call control processing commands and data from said host to said functional layers of said telecommunications switch and a second message type having user-programmable functionality for transferring call control processing status and data from said functional layers of said telecommunications switch to said host.

2. The telecommunications switch of claim 1, wherein said functional layers of said telecommunication switch comprise:

an application layer comprising said telecommunications service applications configured to operate in conjunction with one or more of said functional layers to perform telecommunications service functions.

3. The telecommunications switch of claim 2, wherein said application layer resides in said telecommunications switch and wherein said universal API defines communications that occur over a bus internal to said telecommunications switch.

4. The telecommunications switch of claim 2, wherein said functional layers further include an application layer residing in a host computer system coupled to said telecommunications switch, and wherein said API defines communications that occur over a communication channel coupling said telecommunications switch and said host device.

5. The telecommunications switch of claim 2, wherein said telecommunications services provided by said telecommunication service application includes toll-free service functions.

6. The telecommunications switch of claim 2, wherein said telecommunications service provided by said telecommunication service application includes voice mail service functions.

7. The telecommunications switch of claim 2, wherein said telecommunications service provided by said telecommunication service application includes automatic call distribution service functions.

8. The telecommunications switch of claim 2, wherein said call processing function performed by said telecommunication service application includes interactive voice-response functions.

9. The telecommunications switch of claim 2, wherein said call processing function performed by said telecommunication service application includes personal communications services functions.

10. The telecommunications switch of claim 2, wherein said call processing function performed by said telecommunication service application includes tone generation functions.

11. The telecommunications switch of claim 2, wherein said call processing function performed by said telecommunication service application includes call conferencing functions.

12. The telecommunications switch of claim 2, wherein said call processing function performed by said telecommunication service application includes call management functions.

13. The telecommunications switch of claim 2, wherein said call processing function performed by said telecommunication service application includes call progress tone control functions.

14. The telecommunications switch of claim 2, wherein said call processing function performed by said telecommunication service application includes inbound call routing and queuing functions.

15. The telecommunications switch of claim 1, wherein said functional layers comprise:

a call management layer for performing centralized call processing functions.

16. The telecommunications switch of claim 15, wherein said centralized call processing functions performed by said call management layer includes recorded announcement control functions for interactive voice response application support.

17. The telecommunications switch of claim 15, wherein said centralized call processing functions performed by said call management layer includes reconnection and transfer functions.

18. The telecommunications switch of claim 15, wherein said centralized call processing functions performed by said call management layer includes the provision of multiple call management features.

19. The telecommunications switch of claim 15, wherein said centralized call processing functions performed by said call management layer includes conferencing connection management functions.

20. The telecommunications switch of claim 1, wherein said functional layers comprise:

a network signaling protocol layer for performing network signaling functions.

21. The telecommunications switch of claim 20, wherein said network signaling functions performed by said network signalling protocol layer includes in- and out-of-band network signalling supervision.

22. The telecommunications switch of claim 20, wherein said network signalling functions performed by said network signalling protocol layer includes network protocol level control of incoming and outgoing calls.

23. The telecommunications switch of claim 1, wherein said functional layers comprise:

a link layer for detecting and transferring network signaling information across a network or line interface.

24. The telecommunications switch of claim 23, wherein said link layer runs on a CPU/matrix card.

25. The telecommunications switch of claim 23, wherein said link layer runs on line cards.

26. The telecommunications switch of claim 23, wherein said functions performed by said link layer include T1 robbed bit signal scanning.

27. The telecommunications switch of claim 23, wherein said functions performed by said link layer include E1 channel associated signaling scanning.

28. The telecommunications switch of claim 23, wherein said functions performed by said link layer include T1/E1 line interface frame alarm control.

29. The telecommunications switch of claim 23, wherein said functions performed by said link layer include DSP tone generation control.

30. The telecommunications switch of claim 23, wherein said functions performed by said link layer include DSP recorded voice announcement control.

31. The telecommunications switch of claim 1, said functional layers comprise:

a physical layer implemented in line cards providing physical and electrical network and line interfaces to the switch.

32. The switch as in claim 1, wherein

said switch further comprises one or more state machine engines, and wherein

each said one or more component state machines comprises one or more libraries of predetermined functions,

wherein said each said one or more component state machines is configured to be interpreted by one or more state machine engines.

33. The switch as in claim 1, wherein each of said one or more state machines is defined by a functional combination of a state/event table and a primitive table, wherein

said state/event table defines one or more predetermined logical states and at least one of said one or more predetermined events associated with each said one or more predetermined logical states, and wherein

said primitive table defines one or more primitives each of which comprises a predetermined series of one or more said predetermined functions.

34. The switch as defined in claim 1, wherein said PPL component state machine transmits a PPL event request message comprising:

a PPL component ID for identifying which of said one or more PPL component state machines is referenced by a particular PPL event request message;

one or more address element fields, each identifying one of said one or more instantiations of said PPL component state machine identified in said PPL component ID field; and

a PPL event ID field containing a user-defined event ID representing an associated event unique to a particular PPL component state machine identified in said PPL component ID field.

35. The switch of claim 34, wherein each said one or more address element fields comprises:

an address element type subfield for referencing components of said switch associated with said state machine instantiation identified in said one or more address element fields; and

an address information subfield provides specific addresses for each of the hierarchical components indicated in said address element type field.

36. The switch of claim 34, wherein said PPL event request message further comprises:

one or more data fields associated with each of said one or more PPL component state machines, for transferring call control processing information from said host to said switch.

37. The switch as defined in claim 1, wherein said PPL component state machine transmits a PPL event indication message, comprising:

a PPL component ID for identifying which of said one or more PPL component state machines is referenced by a particular PPL event indication message;

a PPL component ID field for identifying which of said one or more PPL component state machines is referenced by a particular PPL event indication message;

one or more address element fields, each identifying one or said one or more instantiations of said PPL component state machine which has invoked the function that generates said PPL event indication message; and

a PPL event ID field containing a user-defined event ID representing the occurrence of a specific event in said switch that results in a particular PPL event indication message being generated by said PPL component state machine.

38. The switch of claim 33, wherein said PPL event indication message is generated by one of said one or more functions configured to send the particular PPL event indication message in response to the occurrence of a particular event, and wherein each said one or more address element fields comprises:

an address element type subfield for referencing components of said switch associated with said state machine instantiation identified in said one or more address element fields; and

an address information subfield provides specific addresses for each of the hierarchical components indicated in said address element type field.

39. The switch of claim 37, wherein said PPL event indication message further comprises:

one or more data fields associated with each of said plurality PPL component state machines, for transferring call control processing information between said functional layers, said data blocks defined for each said plurality of PPL components based upon which of said functional layers said PPL component state machine is associated with and the communications protocol supported by that PPL component state machine.

40. A method for developing call-associated protocols for performing call processing functions related to communication paths established between various ones of a plurality of channels in a programmable telecommunications switch, said call processing functions associated with the functions performed by a particular functional layer of said switch, the method comprising the steps of:

(a) providing one or more state/event tables each of which defines, a plurality of predetermined logical states, which may be user-definable, one or more predetermined events associated with each of said plurality of predetermined logical states, said one or more predetermined events including receipt of one or more application program interface (API) messages in a generic format and said messages being user-programmable, said messages generated at the same or different functional layer as said call-associated protocol, and

a user-definable primitive associated with each said one or more predetermined events, wherein said primitive is invoked upon an occurrence of said one or more associated events;

(b) providing one or more primitive tables each of which defines a predetermined series of predetermined layer-dependent functions for each said primitive, one or more of said predetermined functions generating an API message to said functional layer and one or more of said predetermined functions having associated therewith user-specified data; and

(c) providing one or more protocols each of which is represented by a predetermined association of one or more of said state/event tables and one or more of said one or more primitive tables.

41. The method of claim 40, further comprising the steps of:

(d) storing said one or more call-associated protocols stored within said programmable telecommunications switch; and

(e) executing said one or more call-associated protocols within said telecommunications switch.

42. The method as defined in claim 40, wherein each of said one or more protocols is represented by a finite state machine having associated therewith a library containing definitions of said predetermined functions, and configured to be interpreted by a state machine engine.