Universal state machine for use with a concurrent state machine space in a telecommunications network

Abstract

A state machine space for concurrent state machines is provided for use in a telecommunications system. Universal State Machines (USMs) use a universal data structure (representing an event in the telecommunications system) as a way for the system architect to dynamically alter the how the events are handled. The USMs are designed to function concurrently with other USMs without requiring explicit knowledge of other USMs or their functionality. A USM definition (USMD) defines a state machine and contains configuration, states and transitions information. An instantiation of a USM includes a USM definition pointer, a current state indicator, a current event processor indicator, and optional lists of event processors and spawned child state machines (other USMDs). Other state machines may be hooked or referenced by a main state machine in its definition. Upon instantiation of the main state machine, other state machines may be hooked or referenced and processing control is transferred to the hooked or referenced state machines to perform functions.

Claims

What is claimed is:

1. A method for processing in a reactive system, comprising the steps of:

providing a first universal state machine definition defining a first universal state machine, the first universal state machine definition comprising,

an entry state,

a first state,

an exit state, and

transition criteria information;

receiving an event message in response to a first event occurring in the reactive system;

generating an instantiated first universal state machine in response to the event message, the instantiated first universal state machine comprising,

a first reference comprising information identifying or pointing to the first universal state machine definition, and

a second reference comprising information identifying or pointing to a current state of the first universal state machine; and

processing the first universal state machine in accordance with its functionality.

2. The method in accordance with claim 1 wherein the step of processing includes the step of applying a first universal data structure to the first universal state machine.

3. The method in accordance with claim 1 wherein the first state is a reference state.

4. The method in accordance with claim 1 wherein the first state is a hook state.

5. The method in accordance with claim 1 wherein the first universal state machine definition of the first universal state machine further comprises a hook transition from a one state to another state.

6. The method in accordance with claim 1 wherein the universal state machine definition is dynamically programmable.

7. The method in accordance with claim 1 further comprising the step of hooking a first event processor into the first universal state machine.

8. The method in accordance with claim 7 wherein the step of hooking comprises the steps of:

relinquishing processing control to the first event processor;

performing a function; and

returning control to the first universal state machine.

9. The method in accordance with claim 8 wherein the first event processor is a second universal state machine and the function is performed according to the functionality of the second universal state machine.

10. The method in accordance with claim 1 wherein the instantiated first universal state machine further comprises a third reference comprising information identifying or pointing to a second universal state machine, and the method further comprises the steps of:

providing a second universal state machine definition defining the second universal state machine, the second universal state machine definition comprising,

an entry state,

a first state,

an exit state, and

transition criteria information; and

generating an instantiated second universal state machine, the instantiated second universal state machine comprising,

a first reference comprising information identifying or pointing to the second universal state machine definition, and

a second reference comprising information identifying or pointing to a current state of the second universal state machine.

11. The method in accordance with claim 10 wherein the first and second universal state machine definitions are dynamically programmable.

12. The method in accordance with claim 10 further comprising the step of hooking the second universal state machine into the first universal state machine.

13. The method in accordance with claim 12 wherein the step of hooking comprises the steps of.

relinquishing processing control to the second universal state machine;

processing the second universal state machine; and

returning control to the first universal state machine.

14. A method for call control processing in a telecommunications system, comprising the steps of:

providing a first universal state machine definition defining a first universal state machine, the first universal state machine definition comprising,

an entry state,

a first state,

an exit state, and

transition criteria information;

receiving an event message in response to a first event occurring in the telecommunications system;

generating an instantiated first universal state machine in response to the event message, the instantiated first universal state machine comprising,

a first reference comprising information identifying or pointing to the first universal state machine definition, and

a second reference comprising information identifying or pointing to a current state of the first universal state machine; and

processing the first universal state machine in accordance with its functionality in response to one or more universal data structures.

15. The method in accordance with claim 14 further comprising the step of hooking a first event processor into the first universal state-machine upon a transition from one state to another state.

16. The method in accordance with claim 14 further comprising the step of hooking a first event processor into the first universal state machine upon reaching a predetermined state.

17. The method in accordance with claim 14 further comprising the step of spawning a second universal state machine, the second universal state machine running concurrently with the first universal state machine during a period of time.

18. The method in accordance with claim 14 wherein the universal state machine definition is dynamically programmable.

19. An apparatus for call control processing in a reactive system, comprising:

means for storing a universal state machine definition defining a universal state machine, the universal state machine definition including an entry state, a first state, an exit state, and transition criteria information;

means for generating an instantiated universal state machine in response to any one of a predetermined set of events occurring in the reactive system, the instantiated universal state machine having a given functionality and comprising,

first means for pointing to or identifying the universal state machine definition, and

second means for pointing to or identifying a current state of the universal state machine; and

means for processing the universal state machine in accordance with its functionality.

20. The apparatus in accordance with claim 19 further comprising means for hooking a first event processor into the first universal state machine.

21. The apparatus in accordance with claim 19 further comprising means for dynamically programming the universal state machine definition.

22. The apparatus in accordance with claim 19 wherein the reactive system comprises a telecommunications system.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

The following co-pending United States patent applications filed concurrently with this application contain related information and are incorporated herein by reference:

U.S. patent application of Daniel James entitled "A UNIVERSAL DATA STRUCTURE FOR USE WITH A CONCURRENT STATE MACHINE SPACE IN A TELECOMMUNICATIONS NETWORK" Ser. No. 08/969,822 filed of even date herewith; and

U.S. patent application of Daniel James entitled "A UNIVERSAL STATE MACHINE FOR USE WITH A CONCURRENT STATE MACHINE SPACE IN A

TELECOMMUNICATIONS NETWORK" Ser. No. 08/969,373 filed of even date herewith.

A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a processing system in a reactive system and, in particular, to a call control processing system using a concurrent state machine processing system in a telecommunications network.

BACKGROUND

Development of new software architecture and applications programs for program controlled telecommunications systems has historically been a complex and time-consuming task. Current software for a large telecommunications network may contain millions of lines of code. Developing new software requires not only developing functional specifications defining the operation and interaction of new software code (new services, enhancements, modifications, etc.) with existing code, but also the testing of the new code with existing code to ensure compatibility. Such a process may take a significant amount of time, thus delaying the operation of new services and software into the marketplace. Thus, developing new software systems and applications is a very expensive and time-consuming process.

Accordingly, there exists a need for a software architecture in a telecommunications system that allows use, and re-use, of modular software components allowing them to be integrated quickly into the existing software. In addition, there is a need for a software architecture useful in a complex telecommunications environment wherein many separate tasks within a particular call may be most appropriately performed concurrently and without explicit prior knowledge of one another. Such an architecture should provide an interpreted and dynamic environment in which not only data definitions are configurable at run-time and modifiable during run-time, but so is the activation, functionality and interaction of state machines.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided a method for control processing in a reactive system. The method includes providing a first universal state machine definition defining a first universal state machine. The first universal state machine definition having an entry state, a first state, an exit state, and transition criteria information. An event is received in response to a first event occurring in the reactive system. In response to the first event an instantiated first universal state machine is generated having a first reference with information identifying or pointing to the first universal state machine definition and a second reference with information identifying or pointing to a current state of the first universal state machine. The first universal state machine is processed in accordance with its functionality.

In another aspect of the present invention, there is provided another method that includes providing a first universal state machine definition defining a first universal state machine. The first universal state machine definition having an entry state, a first state, an exit state, and transition criteria information. An event is received in response to a first event occurring in the telecommunications system. In response to the event an instantiated first universal state machine is generated having a first reference with information identifying or pointing to the first universal state machine definition and a second reference with information identifying or pointing to a current state of the first universal state machine. The first universal state machine is processed in accordance with its functionality in response to one or more universal data structures.

In yet another aspect of the present invention, an apparatus is provided for call control processing in a telecommunications system. The apparatus stores a universal state machine definition defining a universal state machine, the universal state machine definition including an entry state, a first state, an exit state, and transition criteria information. The apparatus also generates an instantiated universal state machine in response to any one of a predetermined set of events occurring in the telecommunications system. The instantiated universal state machine has a given functionality and points to or identifies the universal state machine definition and a current state of the universal state machine. The apparatus processes the universal state machine in accordance with its functionality.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention, and the advantages thereof, reference is made to the following description taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a block diagram of a telecommunications network utilizing the present invention;

FIG. 2 is a block diagram of a switching intelligent unit in accordance with the present invention;

FIG. 3 is an example of a high-level view of the conversion of events into the UDS format;

FIG. 4 is a graphical example of the contents of, and relationships between, the UDSD and UDS;

FIG. 5a is a graphical example of a generic call model using a hook state;

FIGS. 5b thru 5d illustrate in graphical representation a transition hook;

FIGS. 5e thru 5f illustrate in graphical representation a state hook;

FIG. 6 presents an example of a call model definition (state machine) using a reference state;

FIG. 7a presents a simplified diagram of a 1-800 originating call model state machine example showing transition criteria;

FIG. 7b is a simplified diagram of the example shown in FIG. 7a showing function calls;

FIG. 8 illustrates a USMD containing a hook and three examples of instantiated USMs that correspond to the USMD with different event processors hooked into the USMs;

FIG. 9a illustrates the contents of an instantiated USM;

FIG. 9b is a more detailed logical relational view of an instantiated USM and associated USMD;

FIG. 10 is a block diagram illustrating a concurrent state machine space in accordance with the present invention;

FIG. 11 represents a hierarchial view of the activation mapping definition within a concurrent state machine space definition;

FIGS. 12-14 illustrate operation of the present invention in response to an external origination event;

FIG. 15 illustrates a flow diagram of a typical spawning USM and spawned USM;

FIGS. 16-22 are object diagrams of the software architecture of the present invention;

FIG. 23 is a table illustrating a preferred embodiment of valid criteria flags for the criteria flags in FIG. 19;

FIG. 24 is an activity flow diagram illustrating the creation of a UDS definition;

FIG. 25 is an activity flow diagram illustrating the creation of an event definition; and

FIG. 26 is an activity flow diagram illustrating the addition of a state to a USM definition.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the drawings, like reference characters designate like or similar elements throughout the drawings.

Now referring to FIG. 1, there is illustrated, in accordance with the present invention, a telecommunications network 100 that includes a plurality of local exchange carrier (LEC) switches 102, an interexchange carrier (IEC) switch 104, one or more databases 106, an optional reseller switch 108, one or more users 110, and one or more service applications 112. A network 120 interconnects the components of the telecommunications network 100 and processes information and facilitates call control between these components.

The LEC switches 102 are used in smaller, in-area code regions for local exchange distribution and switching and also provide line-oriented services (call-waiting, 3-way calling, etc.). The IEC switch 104 is used for inter-exchange distribution and switching and provides long-distance services. The database 106 (or databases) typically include data that is used for services such as billing, translation, private service, routing, etc. The reseller switch 108 provides distribution and switching onto the network for a reseller who generally purchases long-distance time from an inter-exchange carrier. The one or more users 110 represent a means by which the processing functions of the network 120 may be modified or altered by a user while the network 120 is running. The one or more service applications 112 include service application programs that process selected calls in accordance with the service requested by the call. Such service applications may be remote to the network 120 or split into local and remote portions.

The network 120 includes switching fabric (SF) units 122, 124, 126, 128 interconnected via inter-machine trunks (IMT). The SF units 122, 124, 126, 128 are also typically connected to the LEC switches 102, the IEC switch 104 and the reseller switch 108 via trunk connections. The SF units 122, 124, 126, 128 provide the switching functions or fabric within the network 120. As will be appreciated, any number of SF units may be utilized in the network 120 depending on design characteristics. Also interconnecting the SF units 122, 124, 126, 128 is a processing system 130.

Within the processing system 130, there exist a plurality of switching intelligent (SI) units 132, 134, 136, 138, a database 140, one or more users 142, and an operator 144. The SI units 132, 134, 136, 138 function as a concurrent station machine processing system that processes a call within the network 100 and controls the SF units 122, 124, 126, 128. The database 140 typically stores data that is used for services such as translation, screening, routing, etc. The one or more users 142 may include third party service providers, network administrators, etc. The operator 144 is generally a typical telephone operator that performs manual connect/disconnect/redirect functions and other processing functions for a call.

Now referring to FIG. 2, there is illustrated the contents of each of the SI units 132, 134, 136, 138 with each unit including an interface 200 providing an interface between the SF unit 122, 124, 126, 128 and the SI unit 132, 134, 136, 138 and its internal components. The SI unit also includes a facility control processor (FCP) 202, a call service processor (CSP) 204, a syntax signalling protocol processor (SPP) 206, a semantics SPP 208, a call topology processor (CTP) 210, a screening processor (SP) 214, a translation processor (TP) 216, a routing processor (RP) 218, a billing operations processor (BOP) 220, and a operational measurement and log processor (OMLP) 222. As will be appreciated, the components of the SI unit 132, 134, 136, 138 are processes, with the exception of interface 200 which may include both hardware and software. These processes are preferably performed by software (or software modules) that are executed within a typical computer system (not shown) that includes one or more general-purpose or special-purpose processors, memory, I/O, etc.

The FCP 202 performs facility-specific call control and voice path control functions. The CSP 204 performs call service control and service interaction functions. The syntax SPP 206 converts the protocol-specific information of a protocol telephony event into a Universal Data Structure (described later). The semantics SPP 208 performs signalling protocol specific call control functions and error checking functions on the received protocol message (representing a telephony event) through examination of the Universal Data Structure created by the syntax SPP 206. Alternatively, the semantics SPP 208 may examine the original protocol message. The CTP 210 performs logical representation and control of voice path functions, the SP 214 performs basic screening functions to determine access rights, the TP 216 handles basic translation functions (i.e., dialed number to route list translation), and the RP 218 performs basic routing functions (i.e., route list to terminal id). In addition, the BOP 220 performs billing operations functions and the OMLP 222 functions to perform operational measurements and logs. It will be understood that the SI units 132, 134, 136, 138 (and their components) are generally implemented using software operating within a computer system (not shown). Such a computer system may be a UNIX workstation or NT-based workstation, for example. The software may be implemented in any language such as C++, Java, Smalltalk, or other language.

A. Concurrent State Machine Space (COSMAS).

The processing system 130 of the present invention utilizes a definitional and operational system identified as a concurrent state machine space (COSMAS). COSMAS is a `space` containing state machines that may run concurrently. COSMAS is useful in a reactive system, and especially useful in a complex telecommunications environment wherein many separate tasks within a particular call may be most appropriately performed concurrently and without explicit prior knowledge of one another. COSMAS provides an interpreted and dynamic environment in which not only data definitions are configurable at run-time and modifiable during run-time, but so is the functionality and interaction of the state machines. This modifiability is useful for system add-ons and modifications.

COSMAS is composed of three major components: (1) Universal Data Structure; (2) Universal State Machine; and (3) COSMAS Sub-Space. The Universal Data Structure (UDS) provides a source of normalized or private call data for use by the SI units 132, 134, 136, 138 within the processing system 130 (see FIG. 2). The Universal State Machine (USM) is a state machine that performs functions and/or processing in response to a telephony event that is represented by a UDS. The COSMAS Sub-Space is a collection of state machines (USMs) that corresponds to a particular set of functionality.

B. Universal Data Structure (UDS).

The Universal Data Structure (UDS) is a dynamic data structure that serves the primary purposes of normalizing call data and representing telephony events. It may also be used to hold data private to particular services, customer-specific protocol features and the like. The UDS comprises normalized data and represents telephony events. The UDS may also contain persistent data (for storage purposes) for components of the telecommunications system.

Telephony events include protocol (SS7, ISDN, etc.) messages, timeouts, and requests/responses for translation, digits, feature information, etc., and the like. Generally, it is assumed that nothing happens in the telecommunications system without the occurrence of some "external" event. For example, assuming that the telecommunications system is a long-distance carrier system, then an originating protocol message from a local carrier would be an event external to the system. FIG. 3 presents an example of a high-level view of the conversion of external events into the UDS format.

As illustrated in FIG. 3, a local exchange carrier (or switch) 102 transmits messages representing telephony events, such as SS7 messages 250 or ISDN (Q.931) messages 252, to the inter-exchange carrier (IEC) (comprising the iEC switch 104 and the processing system 120) in the form of standard protocol data messages. Within the SI units 132, 134, 136, 138 these messages are converted into normalized data structures (referred to as universal data structures (UDS)). Within the processing system 120, the UDS is processed and call control processing occurs in accordance with a predetermined call control flow that may also depend on the information contained within the UDS. It will be understood that any other types of events (including notifications) may be transmitted from the LEC switch 102 to the IEC, as desired. Events within the processing system 120 may also be transmitted to the LEC switch 102 in the standard protocol form (e.g. SS7, ISDN, etc.) after they have been converted from UDS form to the standard protocol form.

Additional telephony events may also be received by the processing system 120 and converted into UDS events, including events such as timer events 254 and operator-type events 256 generated from an operator 260. The timer events 254 are shown occurring internal to the IEC, but may also be external to the IEC. Likewise, operator-type events 256 (may be external or internal to the IEC) such as translation or routing requests may be received by the processing system 120 and converted into a UDS event. In response to the UDS event representing such a translation or routing request event, the processing system 120 may respond with a UDS response that is converted into the proper format for handling by the operator 260.

External events come in varying data formats. An event is converted when an external event is received by COSMAS. Although events differ in format, they do tend to carry the same sort of information. For example, an SS7 IAM message and an ISDN PRI SETUP message both contain a called number (or some form of termination information), information about the call originating facility, and other information for triggering specific features. Some or all of this information is normalized; i.e., the called number may be packed differently into both messages, but for processing, the information should look the same to the telecommunications system (e.g., for translation). Likewise for the messages themselves. Both types of messages represent originating events to originate new a call. Upon entering the COSMAS system, both messages are converted into origination UDS events having the same representation for their respective called numbers (including other normalized data). In this way, the telecommunications system removes protocol specificity from call control. COSMAS provides a means and way to maintain consistent call control without protocol specific knowledge.

The UDS also plays the role of persistent data storage container. This pertains to system-wide information as well as call-specific information. The exact placement of a UDS is within the discretion of the system architect. For example, persistent information pertaining to a particular call or call half may be maintained at a certain location or locations, especially for billing processes. Certain information like caller, callee, charge number, etc. should be identified and stored through the life of the call. This information is maintained by a UDS to coincide with the information carried by the transient events that drive the system.

Differentiation is made between the UDS definitional part and the UDS instantiated part. Definitional information is used to indicate what is valid and what is not valid for the system. Instantiated information indicates a particular instance of a UDS. The definitional part is referred to as the universal data structure definition (UDSD), while the instantiated part is referred to as the UDS. The UDSD and UDS are logical separations and do not have to exist in separate structures. UDSD information is considered globally accessible to all instantiations of the UDS such that the entire system maintains a consistent view of what is valid and invalid. Optionally, version information can be used to ensure that certain versions of the UDS are used only by certain versions of components within the SI units or state machines, etc., and vice-versa.

1. Universal Data Structure Definition (UDSD).

In the present invention, the UDS includes four fields which are defined by the UDSD. Three of these fields include events, component type, and data, while an embedded fourth field includes enums. The event field contains information relating to the telephony events that are defined for a given telecommunications system (such as Origination, Translation Request, Release, etc.). The component type field identifies the types of components in the telecommunications system to and from which telephony events may be passed (such as facilities call control, call segment call controls, translator, etc.). The data field includes call data information (such as called number, calling number, etc.). The enums field includes enumerated type definitions for a call data type identified as `enum`. The following universal data structure definition file format grammar preferably provides an example of the UDSD format in accordance with the present invention:

    UniversalDataStructure:: = EVENTS Events.sub.--
                         COMPONENTS Components.sub.--
                         ENUMS Enums.sub.--
                         DATA Data.sub.--
    Events::             = [ Event   Events .vertline. e
    Event::              = NUMBER STRING ComponentPermissions DataPermissions
    Components::         = [ Component ] Components .vertline. e
    Component::          = NUMBER STRING EventPermissions DataPermissions
    Enums::              = [ Enum ] Enums .vertline. e
    Enum::               = NUMBER STRING ( EnumSymbols )
    EnumSymbols::        = EnumSymbol .vertline.
                         EnumSymbol : EnumSymbols
    EnumSymbol::         = NUMBER STRING
    Data::               = [ Datum ] Data .vertline. e
    Datum::              = NUMBER STRING DataType EventPermissions
    ComponentPermissions
    DataType::           = BOOL .vertline.
                         SCALAR .vertline.
                         ENUM NUMBER .vertline.
                         ARRAY
    PermissionMarker::   = READ .vertline. WRITE .vertline. READWRITE
    Permissions::        = Permission Permissions .vertline. e
    Permission::         = PermissionMarker NUMBER
    EventPermissions::   = Permissions
    ComponentPermissions:: = Permissions
    DataPermissions::    = Permissions
    .COPYRGT. 1997 Northern Telecom Limited

          id          events
          [ 0         "Error"                    ]
          [ 1         "Time Alarm Occurred"      ]
          [ 2         "Message"                  ]
          [ 3         "Interrupt"                ]
          [ 4         "Origination"              ]
          [ 5         "Origination Ack"          ]
          [ 6         "Ringing"                  ]
          [ 7         "Answer"                   ]
          [ 8         "Release"                  ]
          [ 9         "Release Ack"              ]
          [ 10        "Termination"              ]
          [ 11        "Redirect"                 ]
          [ 12        "Set Voice Path"           ]
          [ 13        "Billing"                  ]
          [ 14        "Authorization Request`    ]
          [ 15        "Authorization Response`   ]
          [ 16        "Screening Request"        ]
          [ 17        "Screening Response"       ]
          [ 18        "Translation Request"      ]
          [ 19        "Translation Response"     ]
          [ 20        "Routing Request"          ]
          [ 21        "Routing Response"         ]
          [ 22        "Digits Request"           ]
          [ 23        "Digits Response"          ]
          [ 24        "Creation Request"         ]
          [ 25        "Creation Response"        ]
          [ 26        "Retrieval Request"        ]
          [ 27        "Retrieval Response"       ]
          [ 28        "Generic Processing Response" ]
          [ 29        "Conference Unit Response" ]
          [ 30        "Transfer Units Response"  ]
    .COPYRGT. 1997 Northern Telecom Limited

              id  component
              [ 0 "Invalid"   ]
              [ 1 "Proxy"     ]
              [ 2 "Call"      ]
              [ 3 "Facility"  ]
              [ 4 "Call Segment"     ]
              [ 5 "Call Topology"    ]
              [ 6 "Billing Operations" ]
              [ 7 "Operational Measurement & Logs" ]
              [ 8 "Remote Event Handler"   ]
              [ 9 "Utility"   ]
    .COPYRGT. 1997 Northern Telecom Limited

        id    data
        [ 0   "Unused"                         SCALAR    ]
        [ 1   "NOC"                            SCALAR    ]
        [ 2   "USI"                            ARRAY     ]
        [ 3   "FCI"                            SCALAR    ]
        [ 4   "FCI 2"                          SCALAR    ]
        [ 5   "MFCSI"                          SCALAR    ]
        [ 6   "NSF"                            ARRAY     ]
        [ 7   "SI"                             SCALAR    ]
        [ 8   "Generic Digits"                 ARRAY     ]
        [ 9   "TNS"                            ARRAY     ]
        [ 10  "CPC"                            SCALAR    ]
        [ 11  "ChGNum NOA"                     SCALAR    ]
        [ 12  "ChGNum NPI"                     SCALAR    ]
        [ 13  "REL Cause"                      ARRAY     ]
        [ 14  "Calling Party Category"         ENUM 8    ]
        [ 15  "Information Transfer Capability" ENUM 9    ]
        [ 16  "Coding Standard"                ENUM 10   ]
        [ 17  "Voice Path Information Transfer Rate" ENUM 11   ]
        [ 18  "Voice Path Transfer Mode"       ENUM 12   ]
        [ 19  "Establishment"                  ENUM 13   ]
        [ 20  "Configuration"                  ENUM 14   ]
        [ 21  "Structure"                      ENUM 15   ]
        [ 22  "Dest-Orig Information Transfer Rate" ENUM 11   ]
        [ 23  "Symmetry"                       ENUM 16   ]
        [ 24  "Bearer Capability"              ENUM 26   ]
        [ 25  "Multiplier or Layer ID"         ENUM 18   ]
        [ 26  "User Rate"                      ENUM 19   ]
        [ 27  "Asynchronous"                   BOOL      ]
        [ 28  "Nature of Address"              ENUM 20   ]
        [ 29  "Numbering Plan Indicator"       ENUM 21   ]
        [ 30  "Called Number"                  ARRAY     ]
        [ 31  "Terminating Switch ID"          SCALAR    ]
        [ 32  "Terminating Trunk Group"        SCALAR    ]
        [ 33  "Calling Number"                 ARRAY     ]
        [ 34  "Screening Indicator"            ENUM 22   ]
        [ 35  "Presentation Restriction Indicator" ENUM 23   ]
        [ 36  "Backward Charge Indicator"      ENUM 24   ]
        [ 37  "Backward Called Party Status"   ENUM 25   ]
        [ 38  "Backward Called Party Category" ENUM 26   ]
        [ 39  "Backward End-to-End Method"     ENUM 3    ]
        [ 40  "Backward Interworking Indicator" BOOL      ]
        [ 41  "Backward ISDN User Part"        ENUM 4    ]
        [ 43  "Backward Reverse Holding"       BOOL      ]
        [ 44  "Backward ISDN Access"           ENUM 6    ]
        [ 45  "Forward Call Special Indicator" SCALAR    ]
        [ 46  "Origination Trunk Group"        ARRAY     ]
        [ 47  "Origination Switch ID"          ARRAY     ]
        [ 48  "Time Stamp"                     SCALAR    ]
        [ 49  ""Access Transport"              ARRAY     ]
        [ 50  "Current Call ID"                ARRAY     ]
        [ 51  "Current Nodes Point Code"       ARRAY     ]
        [ 52  "Charge Number"                  ARRAY     ]
        [ 53  "Orig TID"                       SCALAR    ]
        [ 54  "Orig TOD"                       SCALAR    ]
        [ 55  "Answ TOD"                       SCALAR    ]
        [ 56  "Term TOD"                       SCALAR    ]
        [ 57  "TSID TTG Indicator"             BOOL      ]
        [ 58  "Dedicated Termination"          BOOL      ]
        [ 59  "No CLI"                         SCALAR    ]
        [ 60  "MNO"                            BOOL      ]
        [ 61  "Spare Array 10"                 ARRAY     ]
        [ 62  "MCI FSCI"                       ARRAY     ]
        [ 63  "MCI BCSI"                       ARRAY     ]
        [ 64  "Spare Array 13"                 ARRAY     ]
        [ 65  "Spare Array 14"                 ARRAY     ]
        [ 66  "Spare Array 15"                 ARRAY     ]
        [ 67  "Spare Array 16"                 ARRAY     ]
        [ 68  "Spare Array 17"                 ARRAY     ]
        [ 69  "Spare Array 18"                 ARRAY     ]
        [ 70  "Spare Array 19"                 ARRAY     ]
        [ 71  "Spare Array 20"                 ARRAY     ]
        [ 72  "Spare Array 21"                 ARRAY     ]
        [ 73  "Spare Array 22"                 ARRAY     ]
        [ 74  "Spare Array 23"                 ARRAY     ]
        [ 75  "Spare Array 24"                 ARRAY     ]
        [ 76  "Spare Array 25"                 ARRAY     ]
        [ 77  "Spare Array 26"                 ARRAY     ]
        [ 78  "Spare Array 27"                 ARRAY     ]
        [ 79  "Originating Line Info"          ARRAY     ]
        [ 80  "OSID OTG Spare"                 SCALAR    ]
        [ 81  "TCM Spare"                      SCALAR    ]
        [ 82  "Protocol"                       ENUM 24   ]
        [ 83  "Screening Result"               ENUM 25   ]
        [ 84  "Translation Result"             BOOL      ]
        [ 85  "Agent ID"                       SCALAR    ]
        [ 86  "Routing Result"                 ENUM 27   ]
        [ 87  "Creation Result"                BOOL      ]
        [ 88  "Retrieval Result"               BOOL      ]
        [ 89  "Digits"                         ARRAY     ]
        [ 90  "Route Request Type"             ENUM 28   ]
        [ 91  "Auth ID"                        ARRAY     ]
        [ 92  "Auth Passcode"                  ARRAY     ]
        [ 93  "Auth Result"                    ARRAY     ]
        [ 94  "Information Indicator"          SCALAR    ]
        [ 95  "Star Component"                 ENUM 29   ]
        [ 96  "User Assigned ID"               SCALAR    ]
        [ 97  "Generic Cause Value"            ENUM 30   ]
        [ 98  "Signalling Point Code"          ARRAY     ]
        [ 99  "Network Call Identifier"        ARRAY     ]
        [ 100 "Translation Type"               ENUM 31   ]
        [ 101 "Screening Type"                 ENUM 32   ]
        [ 102 "Message Type"                   SCALAR    ]
        [ 103 "Incoming Voice Path State"      ENUM 33   ]
        [ 104 "Outgoing Voice Path State"      ENUM 33   ]
        [ 105 "Generic Processing Response Value" BOOL      ]
        [ 106 "Route List"                     ARRAY     ]
        [ 107 "Conference Unit Port List"      ARRAY     ]
        [ 108 "IP Agent ID"                    SCALAR    ]
        [ 109 "Card Number"                    ARRAY     ]
        [ 110 "Number of Transfer Units"       SCALAR    ]
        [ 111 "Trunk Group"                    SCALAR    ]
        [ 112 "Trunk Group Member"             SCALAR    ]
        [ 113 "IP Called Party Number"         ARRAY     ]
        [ 114 "Customer Number"                SCALAR    ]
    .COPYRGT. 1997 Northern Telecom Limited

        id      enums
        [1      "continuity":
                ( 0 "continuity check not required":
                1 "continuity check required":
                2 "continuity check performed on previous circuit") ]
        [2      "call indicator"
                ( 0 "national call":
                1 "international call") ]
        [3      "end to end method indicator"
                ( 0 "no end to end method available":
                1 "pass along method available":
                2 "SCCP method available":
                3 "both methods available":
        [4      "ISDN UP indicator"
                ( 0 "ISDN UP used all the way":
                1 "ISDN UP not used all the way") ]
        [5      "ISDN UP preference indicator"
                ( 0 "ISDN UP preferred all the way":
                1 "ISDN UP not required all the way":
                2 "ISDN UP required all the way":
        [6      "ISDN access indicator"
                ( 0 "non ISDN access":
                1 "ISDN access") ]
        [7      "SCCP method indicator"
                ( 0 "no indication":
                1 "connectionless method available":
                2 "connection oriented method available":
                3 "both methods available") ]
        [8      "calling party category"
                ( 0 "unknown":
                1 "french operator":
                2 "english operator":
                3 "german operator":
                4 "russian operator":
                5 "spanish operator":
                10 "ordinary call subscriber":
                11 "priority subscriber":
                13 "test call":
                15 "payphone":
                16 "digital data call") ]
        [9      "information transfer capability"
                ( 0 "speech":
                8 "unrestricted digital information":
                9 "restricted digital information":
                16 "3.1 kHz audio":
                24 "7 kHz audio":
                18 "15 kHz audio") ]
        [10     "coding standard"
                ( 0 "CCITT":
                1 "other international":
                2 "national") ]
        [11     "info transfer rate"
                ( 0 "channel size":
                1 "channel size":
                16 "64 kbps":
                19 "384 kbps":
                21 "1536 kbps":
                23 "1920 kbps") ]
        [12     "vp transfer mode"
                ( 0 "circuit mode":
                1 "packet mode") ]
        [13     "establishment"
                ( 0 "on demand":
                1 "permanent":
        [14     "configuration"
                ( 0 "point to point":
                3 "multipoint") ]
        [15     "structure"
                ( 0 "default":
                1 "8 kHz integrity":
                4 "service data unit integrity":
                7 "unstructured") ]
        [16     "symmetry"
                ( 0 "bidirectional symmetric":
                1 "bidirectional asymmetric":
                2 "orig to dest":
                3 "dest to orig":
        [18     "multiplier or layer"
                ( 0 "bearer":
                1 "user info layer 1":
                2 "user info layer 2":
                3 "user info layer 3") ]
        [19     "user rate"
                ( 2 "1.2 kbps":
                3 "2.4 kbps":
                5 "4.8 kbps":
                8 "9.6 kbps":
                11 "19.2 kbps":
                15 "56.0 kbps") ]
        [20     "nature of address"
                ( 1 "subscriber number":
                3 "national number":
                4 "international number":
                6 "abbreviated number":
                113 "operator requested subscriber number":
                114 "operator requested national number":
                115 "operator requested international number":
                116 "operator requested no number":
                117 "cut through to carrier":
                118 "950 call":
                119 "test call":
                120 "mci vnet":
                122 "operator to operator":
                123 "operator to operator outside USA":
                124 "direct termination overflow") ]
        [21     "numbering plan"
                ( 0 "unknown":
                1 "ISDN":
                3 "CCITT data":
                4 "CCITT telex":
                5 "private") ]
        [22     "screening indicator"
                ( 0 "user provided not screened":
                1 "user provided passed screen":
                2 "user provided failed screen":
                3 "network provided") ]
        [23     "address presentation restriction"
                ( 0 "presentation allowed":
                1 "presentation restricted":
                2 "address unavailable") ]
        [24     "protocols"
                ( 0 "Nortel ISUP":
                1 "Nortel PRI") ]
        [25     "screening results"
                ( 0 "complete":
                1 "block":
                2 "invalid calling card":
                3 "invalid debit card") ]
        [26     "bearer capability"
                ( 0 "Speech":
                1 "Unrestricted 64 kps":
                2 "Restricted 64 kps":
                3 "Unrestricted 56 kps":
                4 "3.1 kHz Audio") ]
        [27     "routing results"
                ( 0 "success":
                1 "failure":
                2 "already allocated") ]
        [28     "route request types"
                ( 0 "normal":
                1 "vpn") ]
        [29     "star components"
                ( 0 "invalid":
                1 "proxy":
                2 "star call":
                3 "fop":
                4 "csp":
                5 "ctp":
                6 "bop":
                7 "omlp":
                8 "remote event handler":
                9 "star utility") ]
        [30     "generic cause values"
                ( 0 "normal clearing":
                1 "all routes busy") ]
        [31     "translation types"
                ( 0 "invalid":
                1 "nanp":
                2 "tsid/ttg":
                3 "operator":
                4 "treatment") ]
        [32     "screening types"
                ( 0 "invalid":
                1 "nanp":
                2 "calling card":
                3 "debit card":
                4 "long-distance phone-tag") ]
        [33     "voice path states"
                ( 0 "active":
                1 "inactive":
                3 "no change") ]
    .COPYRGT. 1997 Northern Telecom Limited

    UniversalStateMachine:: = CONFIGURATION Configuration.sub.--
                           STATES States.sub.--
                           TRANSITIONS Transitions.sub.--
    Configuration::        = NAME = STRING .vertline.
                           CSSD = STRING .vertline.
                           ABSORBING = BOOL .vertline.
                           ABSORBABLE = BOOL .vertline.
                           INTERRUPTABLE = BOOL .vertline.
                           REENTRANT = BOOL .vertline.
                           SHARED = BOOL .vertline.
                           PRIVATEADATA = NUMBER DEFAULT .vertline.
                           NUMBER LATEST .vertline.
                           NUMBER VERSION NUMBER NUMBER
    States::               = [ State ] States .vertline. e
    State::                = Stateitem State .vertline. e
    StateItem::            = NUMBER = NUMBER .vertline.
                           LABEL = STRING .vertline.
                           TYPE = StateType .vertline.
                           REENTRY = ACTIVATE NUMBER .vertline.
                           REENTRY = DEACTIVATE NUMBER .vertline.
                           SPAWN = STRING NUMBER .vertline.
                           HOOKCMD = STRING STATE STRING .vertline.
                           HOOKCMD = STRING TRANS STRING .vertline.
                           X = NUMBER .vertline.
                           Y = NUMBER
    StateType::            = NORMAL .vertline. HOOK STRING .vertline. REFERENCE
     STRING
    Transitions::          [ Transition ] Transitions .vertline. e
    Transition::           = TransitionItem Transition .vertline. e
    TransitionItem::       = FROMSTATE = NUMBER .vertline. e
                           TOSTATE = NUMBER .vertline.
                           TYPE = TransitionType .vertline.
                           NUMBER = NUMBER .vertline.
                           REENTRY = ACTIVATE NUMBER .vertline.
                           REENTRY = DEACTIVATE NUMBER .vertline.
                           SPAWN = STRING NUMBER .vertline.
                           HOOKCMD = STRING STATE STRING .vertline.
                           HOOKCMD = STRING TRANS STRING .vertline.
                           LABEL = STRING .vertline.
                           X = NUMBER .vertline.
                           Y = NUMBER .vertline.
                           H = NUMBER .vertline.
                           W = NUMBER .vertline.
                           EVENT = CriteriaMarker NUMBER .vertline.
                           ORIGCOMP = CriteriaMarker NUMBER .vertline.
                           ORIGCOMPID = CriteriaMarker NUMBER .vertline.
                           DATA = { Data } .vertline.
                           FUNCTIONS = { Functions }
    TransitionType::       = NORMAL .vertline. DEFAULT .vertline. NULL
     .vertline. HOOK STRING .vertline.
                           REFERENCE STRING
    Data::                 = [Datum] Data .vertline. e
    Datum::                = NUMBER = DONT_CARE .vertline.
                           NOT_SET .vertline.
                           SET .vertline.
                           EQUAL .vertline.
                           NOTEQUAL .vertline.
                           GREATER .vertline.
                           LESS .vertline.
                           GREATER_EQUAL .vertline.
                           LESS_EQUAL .vertline.
                           e
    DataValue::            = BOOL BOOL .vertline.
                           SCALAR NUMBER .vertline.
                           ENUM NUMBER .vertline.
                           ARRAYLEN NUMBER .vertline.
                           ARRAY (NUMBERLIST)
    Functions::            = [ Function ] functions .vertline. e
    Function::             = NUMBER = ( Function Parameters )
    FunctionParameter::    = FunctionParameter FunctionParameters .vertline. e
    FunctionParameter::    = BOOL NORMAL BOOL .vertline.
                           BOOL DATA Udsld Datald .vertline.
                           STRING NORMAL STRING .vertline.
                           NUMBER NORMAL NUMBER .vertline.
                           NUMBER EVENT_ID Udsld .vertline.
                           NUMBER COMPCLASS Udsid .vertline.
                           NUMBER COMPIID Udsld .vertline.
                           NUMBER DATA Udsld Datald .vertline.
                           NUMBER ARRAY_ITEM Udsld Datald NUMBER .vertline.
                           ARRAY NORMAL (NUMBERLIST) .vertline.
                           ARRAY DATA Udsld Datald
    Udsld::                = NUMBER
    Datald::               = NUMBER
    .COPYRGT. 1997 Northern Telecom Limited

                         USM INTERPRETATION ALGORITHM
    main:
    if currently processing an event
        queue event
    otherwise
        for every state machine in the sub-space
            process event
            if exited
                remove state machine from sub-space
            if event was consumed
                break out of for loop
        perform functions returned from state machines processing event
        process queued events
    process event:
    process reentry transitions
    if no transition
        process hooks and references
        if no transition
            process normal transitions
            if no transition
                process default transitions
    return process return value
    do transition:
    set return value to false
    set process null transitions flag to false
    if transition type is hook or reference
        if get hooked/referenced state machine
            set hooked/referenced state machine as a current state machine
            process hooks and references
            if processing ok
                set current state id to the to-state of the given transition
                set return value to true
            otherwise if exited
                set current state id to the to-state of the given transition
                set return value to true
                set process null transitions flag to true
    otherwise if transition type is normal default or null
        if event possesses transition criteria
            if processing reentry flag is true and to-state of the given
     transition is flagged
            to say in current state
                do not change the current state
            otherwise
                change current state to the to-state of the given transition
            add the given transition's functions to the function list
            set the return value to true
            set the process null transitions flag to true
    if return value is set to true
        if the given transition or new state indicates to activate any reentry
     transitions
            activate the indicated reentry transitions
        if the given transition or new state indicates to spawn any other state
     machines
            spawn the indicated state machines
        if the given transition or new state indicates to hook/reference any
     other state machines
            hook/reference the indicated state machines in the given places
    if process null transitions flag is true
        process null transitions
    return return value
    process default transitions:
    for each default transition from current state
        if do transition
            if at exit state
                return exited
            otherwise
                return processing ok
    return no transition
    process hooks and references:
    if state machine is currently hooked/referenced in
        have that state machine process the current event
        if processing ok
            return processing ok
        if no transition
            release hooked/referenced state machine
            return to current state in this machine
            return to transition
        if exited
            release hooked/referenced state machine
            return to current state in this machine
            process null transitions
            if processing ok or no transition
                return processing ok
            if exited
                return exited
    return no transition
    process normal transitions:
    for all normal transitions from current state
        if do transition
            if at exit state
                return exited
            otherwise
                return processing ok
    return no transition
    process null transitions:
    for all null transitions from current state
        if do transition
            if at exit state
                return exited
            otherwise
                return processing ok
    return no transition
    process reentry transitions:
    set processing reentry flag to true
    for all active reentry transitions
        if do transition
            if at exit state
                set processing reentry flag to false
                return exited
            otherwise
                set processing reentry flag to false
                return processing ok
    set processing reentry flag to false
    return no transition
    .COPYRGT. 1997 Northern Telecom Limited

    CosmasSubSpace ::    = CONFIGURATION Configuration.sub.--
                         USMDS Usmds.sub.--
                         MAPPINGS Mappings.sub.--
    Configuration::      = ConfigurationItem Configuration .vertline.
    Configuration Item :: = NAME = STRING
    Usmds::              = [Usmd] Usmds .vertline. e
    Usmd::               = NUMBER STRING
    Mappings::           = [Mapping] Mappings .vertline. e
    Mapping::            = USMDS = {NUMBERLIST}
                         Hooks
                         EVENTS - {EventCriteria}
                         SETEVENT = {EventSettings}
    Hooks::              = Hook Hooks .vertline. e
    Hook::               = HOOK = NUMBER INTO NUMBER AT
                         TRANS STRING
                         HOOK = NUMBER INTO NUMBER AT
                         STATE STRING
    EventCriteria::      = EventCriterium Event Criteria .vertline. e
    EventCriterium::     = EVENT = NUMBER .vertline.
                         EVENT = ANY .vertline.
                         COMPCLASS = NUMBER .vertline.
                         COMPCLASS = ANY .vertline.
                         COMPIID = NUMBER .vertline.
                         COMPIID = ANY .vertline.
                         DATA = [NUMBER = DataVal] .vertline.
                         DATA = [NUMBER = ANY]
    DataVal::            = BOOL BOOL .vertline.
                         SCALAR NUMBER .vertline.
                         ENUM NUMBER .vertline.
                         ARRAY (NUMBERLIST)
    EventSettings::      = EventSetting EventSetting .vertline. e
    EventSetting::       = EVENT = NUMBER .vertline.
                         COMPCLASS = NUMBER
                         COMPIID = NUMBER
                         DATA = [NUMBER = DataVal]
    .COPYRGT. 1997 Northern Telecom Limited

    get/create full list referring to all possible USMDs for this component
    (sub-space) called USMDS
    get/create full list of hook information called HOOKS
    get result of mapping for given event id
    if success then
        intersect resulting USMD list with USMDS
        intersect resulting hook information list with HOOKS
    get result of mapping for given component type
    if success then
        intersect resulting USMD list with USMDS
        intersect resulting hook information list with HOOKS
    for every data item in the given event, get result of mapping
        if success then
            intersect resulting USMD list with USMDS
            intersect resulting hook information list with HOOKS
    return USMDS and HOOKS
    .COPYRGT. 1997 Northern Telecom Limited

    get/create full list referring to all possible USMDs for the component
    (sub-space) called USMDS
    get/create full list of hook information called HOOKS
    get result of mapping for given event id
    if success then
        intersect resulting USMD list with USMDS
        intersect resulting hook information list with HOOKS
    get result of mapping for given component type
    if success then
        intersect resulting USMD list with USMDS
        intersect resulting hook information list with HOOKS
    get/create empty scope context, containing no data in mappings
    if scope set exists for given event id then
        union mapping context with the set of data mappings that fall
        under the scoping of given event id
    union mapping context with the set of data mappings that are not scoped
    by any event id
    if scope exists for given component type then
        union mapping context with the set of data mappings that fall
        under the scoping of given component type
    for every data item in the given event, get result of mapping in the
     current
    scope context
        if success then
            intersect resulting USMD list with USMDS
            intersect resulting hook information list with HOOKS
    return USMDS and HOOKS
    .COPYRGT. 1997 Northern Telecom Limited

     id   function
      0   UDS_CLEAR                    (uds_id)
      1   UDS_COPY_ALL                 (dest_uds_id, src_uds_id)
      2   UDS_SET_EVENT                (uds_id, event_id)
      3   UDS_SET_DATA                 (uds_id, data_id, dataval)
      4   UDS_SET_ARRAY_DATA           (uds_id, data_id, offset,
                                       data_val)
      5   UDS_RELAY                    (uds_id, component_class,
                                       component_instance_id)
      6   UDS_NEWTEMP                  ( )
     10   SU_DIGITS_COLLECT            (mindigs, maxdigs, timeout)
     11   SU_DIGITS_MONITOR            (digit)
     12   SU_TRANSLATE                 (uds_id)
     13   SU_SCREEN                    (uds_id)
     14   SU_IP-PLAYMESSAGE            (trkmem, user_id, msgnum)
     15   SU_ROUTE                     (uds_id)
     16   SU_IP_COLLECTDIGITS          (trkmem, maxdigs, timeout)
     17   SU_AUTH_VERIFYACCOUNT        (vendor_id, card_number,
                                       calling_number)
     18   SU_AUTH_TRANSFERUNITS        (vendor-id, card_number,
                                       calling_number,
                                       called_number)
     19   SU_IP_PLAYMESSAGE_NUM        (trkmem, user_id, msgnum,
                                       number)
     20   CTP_PARTY_ADD                ( )
     21   CTP_PARTY_HOLD               ( )
     22   CTP_PARTY_REMOVE             ( )
     30   CSP_ASSOCIATE                (agent_id)
     31   CSP_DISASSOCIATE             (agent_id)
     32   CSP_TIMESLARM_SET            (seconds)
     33   CSP_TIMEALARM_CANCEL         ( )
    .COPYRGT. 1997 Northern Telecom Limited

     id   function
      0   UDS_CLEAR                    (uds_id)
      1   UDS_COPY_ALL                 (dest_uds_id, src_uds_id)
      2   UDS_SET_EVENT                (uds_id, event_id)
      3   UDS_SET_DATA                 (uds_id, data_id, data_val)
      4   UDS_SET_ARRAY_DATA           (uds_id, data_id, offset,
                                       data_val)
      5   UDS_RELAY                    (uds_id, component_class,
                                       component_instance_id)
      6   UDS_NEWTEMP                  ( )
     10   SU_PSM_HANDLE_EVENT          (uds_id)
     20   SET_VOICE_PATH               (incoming_vpstate,
                                       outgoing_vpstate)
    .COPYRGT. 1997 Northern Telecom Limited

    id  function
     0  UDS_CLEAR                (uds_id)
     1  UDS_COPY_ALL             (dest_uds_id, src_uds_id)
     2  UDS_SET_EVENT            (uds_id, event_id)
     3  UDS_SET_DATA             (uds_id, data_id, data_val)
     4  UDS_SET_ARRAY_DATA       (uds_id, data_id, offset, data_val)
     5  UDS_RELAY                (uds_id, component_class,
                                 component_instance_id)
     6  UDS_NEWTEMP              ( )
    .COPYRGT. 1997 Northern Telecom Limited

    main:
    if there is no active sub-space
        get sub-space
        if failure
            if there are any inactive sub-spaces
                activate the inactive one with highest priority
        otherwise
            exit main
    (USM Interpretation Algorithm goes here)
    if exited
        remove active sub-space
        if there are any inactive sub-spaces
            activate the inactive one with highest priority
    get sub-space:
    ask sub-space definition for activation mapping information for the given
    event
    if success
        instantiate the indicated state machines
        if there is hook/reference information
            instantiate the state machines to be hooked or referenced
            associate the new state machines with their hooks or references
        if there is event altering information
            set the indicated event information in the given event
        return success
    return failure
    .COPYRGT. 1997 Northern Telecom Limited