Operational test device and method of performing an operational test for a system under test

• US 6,011,830 A
• Filed: 12/09/1997
• Issued: 01/04/2000
• Est. Priority Date: 12/10/1996
• Status: Expired due to Term

• Current Assignee: Optis Wireless Technology, LLC (Brevet Capital)
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Kreuer, Dieter, Sasin, Tiberius, Hermanns, Steffen
• Primary Examiner(s): Kuntz, Curtis A.
• Assistant Examiner(s): NGUYEN, DUC MINH
• Application Number:
  US08/987,765
• Time in Patent Office: 756 Days
• Field of Search: 379/1-2, 379/9-11, 379/14-15, 379/34, 455/423-425, 455/9, 455/67.1, 455/67.4
• US Class Current: 379/10.03
• CPC Class Codes: H04M 3/323 for the arrangements providing the connection (test connection, test call, call simulation)
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements

Abstract

The invention relates to an operational test device and a method of executing an operational test for a test system which can assume a number of operating states. A test case generator (TCG) is provided for generating a number of test cases which are sent via a test device interface (INT) to the system under test (SUT). A test state model of the test system is ascertained by a test state model generator (TSTM-G) from information on the hardware configuration of the test system (SUT), information on the possible operating states of the test system (SUT), information on the test commands necessary for bringing about changes in operating state within the test system (SUT), and from traffic values which indicate transitional probabilities ascertained in the test system'"'"'s real application for the operating states. Test commands are generated on the basis of a Monte-Carlo simulation of this test state model. The operational test device is particularly suitable for use with a Petri net state model for testing a telephone network or in particular a mobile telephone network, such as a GSM network, e.g. for interrupting connection lines therein.

Claims

1. An operational test device for executing an operational test (LT, DT, CT) for a test system (SUT) that has operating states corresponding to a real operating system (SUT-RA) used in a real operating environment, under test conditions, comprising:

a) a test case generator (TCG) for generating a number of test cases (TC) with test commands that are each intended to produce a desired change in operating state within said test system;

b) a test device interface (INT) for receiving said test commands and for outputting corresponding operating signals to the test system (SUT) for bringing about said desired changes in operating state;

c) said test case generator (TCG) comprising;

a test state model generator (TSTS-G, PNM-G) for generating a test state model of the test system (SUT) from information on the hardware configuration of the test system (SUT), information on the possible operating states of said real operating system (SUT-RA), from traffic values that indicate transitional probabilities ascertained during the real application of said operating system (SUT-RA) for said operating states, and from the permitted test commands of the test system (SUT);

a test state model store (TSTM-S, PNM-S) in which said test state model is stored;

a test state model simulator (TSTM-Sim, PNM-Sim) that statistically passes through said test state model and in doing so generates desired operating state transitions; and

a test state model command generator (TSTM-CG, PNM-CG) for successively generating the test commands of said test cases (TC) on the basis of said operating state transitions generated by said test state model simulator.

2. An operational test device according to claim 1, wherein

said test state model command generator (TSTM-CG, PNM-CG) passes through said test state model in a Monte-Carlo simulation in a random manner, but according to natural statistical rules.

3. An operational test device according to claim 2, wherein

said test device interface (INT) receives from said test system (SUT) operating response signals which each indicate a change in operating state executed in said test system as a response to the respective operating signal, and outputs corresponding operating response signals to said test case generator (TCG).

4. An operational test device according to claim 3, wherein

said test case generator (TCG) includes a comparer (CMP), said test state model simulator (TSTM-Sim, PNM-Sim) generating expected operating response signals of said test system (SUT) on the basis of said state model and storing them in a store (buffer B), storing the operating response signals generated by said test system (SUT) in response to the successively transmitted test commands in a store (buffer A), said comparer (CMP) comparing the operating response signals observed by said test system with expected operating response signals generated during simulation, and generating an error output when said stored expected and observed operating response signals do not match.

5. An operational test device according to claim 2, wherein

said test state model generator (TSTM-G) generates a test state model of the test system (SUT) on the basis of a Markow chain model.

6. An operational test device according to claim 2, wherein

said test case generator (TCG) generates test commands that indicate a corresponding operational function to be executed by the test system (SUT) when there is a change in state within said test system.

7. An operational test device according to claim 2, wherein

said test state model generator (PNM-G) generates a test state model of the test system (SUT) on the basis of a Petri net model (PNM).

8. An operational test device according to claim 2, wherein

the test system (SUT) is a telephone network and/or a mobile telephone network.

9. An operational test device according to claim 8, wherein

said test case generator (TCG) transmits test commands for performing a load test (LT) by means of a load test command generator (LT-TCE) to a switching center (MSC) and/or local switching center (BSC) of a mobile telephone network.

10. An operational test device according to claim 8, wherein

said test case generator (TCG) generates test commands for a conformance test (CT) by means of a conformance test command generator (CT-TCE) which controls a series of mobile telephones (MS) and an air interface simulator (AIS), and generates in this manner the user traffic of a mobile telephone network.

11. An operational test device according to claim 8, wherein

said test case generator (TCG) generates test commands for a disturbance test (DT) by means of a disturbance test command generator (DT-TCE) which can systematically interrupt or disrupt lines between the switching centers of a mobile telephone network and/or can render inoperative or disrupt components within a switching center computer.

12. An operational test device according to claim 8, wherein

said mobile telephone network is a GSM mobile telephone network and said telephone network is a conventional public switched telephone network (PSTN).

13. An operational test device according to claim 7, wherein

a) said test state model generator (TSTM-G) executed as a Petri net model generator (PNM-G) writes the generated Petri net state model of the test system (SUT) into a Petri net model store (PNM-S);

b) said test state model simulator (TSTM-Sim, PNM-Sim) is a Petri net model simulator (PNM-Sim) that contains a Petri net marking store (MSt) used to store a current operating state of said Petri net;

c) said Petri net model simulator (PNM-Sim) reads the current state of said Petri net model from said Petri net marking store (MSt) as a current marking of all the places with tokens (

), reads the Petri net state model (PNM) of said test system (SUT) from said Petri net model store (PNM-S), selects in a randomly controlled manner one of the possible state transitions given by the current marking and the structure of said Petri net model, calculates the new marking resulting from this state transition and stores it as a current marking in the marking store (MSt); and

d) said test state model command generator is a Petri net model command generator (PNM-CG) which is informed by said Petri net model simulator (PNM-Sim) about the performed transition, with the result that it loads from said Petri net model store (PNM-S) the corresponding test commands which constitute said generated test case, and passes them on to the test system (SUT).

14. An operational test device according to claim 13, wherein

said test state model store (TSTM-S, PNM-S) is a Petri net model store (PNM-S) which is provided for storing

places (◯

) of said Petri net, said places indicating the possible operating states of individual operating means, services or components of said test system (SUT);

transitions (|) of said Petri net, said transitions describing the possible changes in state within said state model and including the operational function to be executed in the form of actions; and

edges (→

) which connect places to transitions and transitions to edges and which indicate the conditions that have to be satisfied before or after a transition is switched, wherein these conditions are given by that marking of the places connected to the transition via edges which is necessary for said transition and results therefrom; and

an initial marking of the places of said Petri net state model (PNM), comprising tokens (

) that specify the model'"'"'s initial state before starting the simulation or test case generation.

15. An operational test device according to claim 3, wherein

a) said test state model generator (TSTM-G) executed as a Petri net model generator (PNM-G) writes the generated Petri net state model of said test system (SUT) into a Petri net model store (PNM-S);

b) said test state model simulator (TSTM-Sim, PNM-Sim) is a Petri net model simulator (PNM-Sim) that contains a Petri net marking store (MSt) used to store a current operating state of said Petri net;

c) said Petri net model simulator (PNM-Sim) reads the current state of said Petri net model from said Petri net marking store (MSt) as a current marking of all the places with tokens (

), reads the Petri net state model (PNM) of said test system (SUT) from said Petri net model store (PNM-S), selects in a randomly controlled manner one of the possible state transitions given by the current marking and the structure of said Petri net model, calculates the new marking resulting from this state transition and stores it as a current marking in the marking store (MSt);

d) said test state model command generator is a Petri net model command generator (PNM-CG) which is informed by said Petri net model simulator (PNM-Sim) about the performed transition, with the result that it loads from said Petri net model store (PNM-S) the corresponding test commands which constitute said generated test case, and passes them on to the test system (SUT); and

said test case generator (TCG) further comprises;

a signal handler (PNM-SH) for receiving said operating response signals, for detecting a current change in state of the test system (SUT) from said operating response signals, and for outputting a current change in state in the form of tokens to said Petri net marking store (MSt) for synchronizing the current state of said Petri net to the current operating state of said test system (SUT).

16. An operational test device according to claim 15, wherein

said test case generator (TCG) generates test commands that indicate a corresponding operational function to be executed by the test system (SUT) when there is a change in state within said test system;

and

when said operating response signals indicate not only the mere occurrence of a change in state but also an operational function executed when there is a change in state within the test system (SUT) in response to the outputting of said test command, said signal handler (PNM-SH) passes on to said Petri net marking store (MSt) not only the occurrence of a change in state but also a value (colored token) corresponding to said executed operational function for updating the current state for the purpose of synchronization.

17. An operational test device according to claim 14, wherein

said signal handler (PNM-SH) generates from the information on the hardware configuration a number of tokens (

) which each indicate an operating means available within said test system or a state thereof (auto-configuration).

18. An operational test device according to claim 6, wherein

said signal handler (PNM-SH) generates from the information on the hardware configuration a number of tokens (

) which each indicate an operating means available within said test system or a state thereof (auto-configuration); and

said signal handler generates colored tokens (

) which indicate not only the presence of an operating means within said test system but also its identity in the form of a value.

19. An operational test device according to claim 17, wherein

said Petri net model store (PNM-S) comprises a predetermined number of synchronization places (), wherein a transition (|) connected to such a synchronization place () and if necessary to other places (◯

) via input edges can only be fired when said signal handler (PNM-SH) announces a change in state within the test system (SUT) via this synchronization place () within said Petri net state model in that on account of a response operating signal, said signal handler places a token into said synchronization place ().

20. An operational test device according to claim 18, wherein

said Petri net model store (PNM-S) comprises a predetermined number of synchronization places (), wherein a transition (|) connected to such a synchronization place () and if necessary to other places (◯

) via input edges can only be fired when said signal handler (PNM-SH) announces a change in state within the test system (SUT) via this synchronization place () within said Petri net state model in that on account of a response operating signal, said signal handler places a token into said synchronization place (); and

said Petri net model store (PNM-S) comprises a predetermined number of colored synchronization places (), wherein a transition (|) connected to such a colored synchronization site () and other colored sites (◯

) via input edges with edge addresses can only be fired when as a result of a response operating signal said signal handler (PNM-SH) places a colored token into said synchronization place (), the value of which matches that of the tokens in all said colored places (◯

) that are connected via input edges of the same edge address to said transition (|).

21. An operational test device according to claim 14, wherein

said Petri net model store (PNM-S) comprises a predetermined number of synchronization places (), wherein a transition (|) connected to such a synchronization place () and if necessary to other places (◯

) via input edges can only be fired when said signal handler (PNM-SH) announces a change in state within said test system (SUT) via this synchronization place () within said Petri net state model in that on account of a response operating signal, said signal handler places a token into said synchronization place (); and

a place (◯

) or a synchronization place () is provided with a latency (Δ

T) so that a token stored therein is activated only after a delay time (Δ

T) predetermined by the latency expires, wherein the latency comprises a fixed or a random value given by a stochastic distribution and which varies from token to token according to this stochastic distribution, and wherein latencies realize either a real time interval (real time) or a simulated time interval (virtual or simulation time).

22. An operational test device according to claim 13, wherein

a) a reset state store (RSt) is present that can store at least a marking of said Petri net as a reset state (snap shot);

and

b) said Petri net model simulator (PNM-Sim) comprises a reset means (RS) to read a reset state (snap shot) out of said reset store (RSt) and to reset the current state of said Petri net (i.e. the current marking) within said Petri net marking store (MSt) to said read-out reset state.

23. An operational test device according to claim 22, wherein

at least one predetermined reset marking (snap shot) is stored in said reset state store (RSt) and said reset means (RS) sets the current distribution of the tokens in said Petri net marking store (MSt) to said reset distribution of tokens.

24. An operational test device according to claim 22, wherein

said reset state store (RS) stores as reset states said Petri net'"'"'s current markings (snap shots) which the Petri net assumes during simulation.

25. An operational test device according to claim 15, wherein

said test case generator (TCG) generates test commands that indicate a corresponding operational function to be executed by said test system (SUT) when there is a change in state within said test system;

and

when said operating response signals indicate not only the mere occurrence of a change in state but also an operational function executed when there is a change in state within the test system (SUT) in response to the outputting of said test command, said signal handler (PNM-SH) passes on to said Petri net marking store (MSt) not only the occurrence of a change in state but also a value (colored token) corresponding to said executed operational function for updating the current state for the purpose of synchronization;

a) a reset state store (RSt) is present that can store at least a marking of said Petri net as a reset state (snap shot); and

b) said Petri net model simulator (PNM-Sim) comprises a reset means (RS) to read a reset state (snap shot) out of said reset store (RSt) and to reset the current state of said Petri net (i.e. the current marking) within said Petri net marking store (MSt) to said read-out reset state; and

when there is a lack of agreement between the current state of said test system (SUT) and the current state of said Petri net, said reset means (RS) resets the state of said Petri net to a reset state (snap shot) and test commands are simultaneously generated for resetting the test system (SUT) to a state corresponding to said reset state.

26. An operational test device according to claim 8, wherein

said test state model store (TSTM-S, PNM-S) is a Petri net model store (PNM-S) which is provided for storing

places (◯

) of said Petri net, said places indicating the possible operating states of individual operating means, services or components of said test system (SUT);

transitions (|) of said Petri net, said transitions describing the possible changes in state within said state model and including the operational function to be executed in the form of actions; and

edges (→

) which connect places to transitions and transitions to edges and which indicate the conditions that have to be satisfied before or after a transition is switched, wherein these conditions are given by that marking of the places connected to the transition via edges which is necessary for said transition and results therefrom; and

an initial marking of the places of said Petri net state model (PNM), comprising tokens (

) that specify the model'"'"'s initial state before starting the simulation or test case generation; and

a) said tokens (

) represent the subscribers of the telephone network, connections between them, other network services used by them, and/or timers;

b) said places (◯

) indicate the states which can be assumed by said subscribers, connections between said subscribers, telephone network services used by said subscribers, or timers within said test system (SUT); and

c) said transitions (|) represent operational functions by which said subscribers within said net can produce a change in state, or reflect changes in state of the subscribers themselves.

27. An operational test device according to claim 26, wherein

said subscribers are telephones of a conventional telephone network (PSTN) or are mobile telephones of a mobile telephone network.

28. An operational test device according to claim 14, wherein

said transitions can fire with a deterministic priority or a stochastic priority, thus enabling both random and deterministic command sequences to be generated.

29. An operational test device according to claim 21, wherein

latency-encumbered places are used in real time for generating test cases and identifying errors for the test system (SUT) in that the simulation of latencies is performed in real time and delayed state transitions controlled in this manner by latencies in said Petri net model (PN) lead to corresponding delays in the state transitions of the test system (SUT), and the punctual occurrence of state changes in the test system (SUT), which by means of fed-back signals of the test system (SUT) is rendered identifiable in the form of tokens generated in synchronization places, is monitored by means of latency-encumbered places that are switched as timers in said Petri net model (PN).

30. An operational test device according to claim 2, wherein

said test state model is stored permanently or temporarily, i.e. during its simulation, within said test state model store (TSTM-S, PNM-S).

33. An operational test device according to claim 1, wherein

a) the test system (SUT) is formed by a telephone communication device (KV) that contains a plurality of telephones (T₁ to T_n), particularly mobile telephones, a plurality of electrical connection lines, as well as at least one transmission station (UEV) for transmitting signals within said telephone communication device (KV);

and

b) the test device interface (INT) and test case generator (TCG) form a test device (TV) for testing said telephone communication device (KV) in an operative load condition, said test device (TV) comprising;

b1) a central signal processing device (ZV) having

b11) at least one programmable data processing device (S) by which said test commands for testing said telephone communication device (KV) are supplied; and

b12) a converter device (WV) connected to said programmable data processing device (S) and designed to convert digital signals, generated by said programmable data processing device (S) by controlling said test commands, into said operating signals; and

b2) at least one interrupt device (UV) connected to said converter device (WV) and designed to interrupt systematically, in accordance with said operating signals, individual or groups of electrical connection lines for time intervals predetermined by said operating signals of said converter device (WV), wherein

b3) on account of said systematic interruptions in said telephone communication device (KV), signal changes are produced which can be signaled when there is a deviation from the associated reference signal changes.

34. An operational test device according to claim 33, wherein

individual or groups of electrical connection lines arranged within at least said one transmission station (UEV) and/or between different transmission stations (UEV) can be interrupted by said interrupt device (UV).

35. An operational test device according to claim 33, wherein

response signals obtained from said transmission station (UEV) by said converter device (WV) can be converted into digital operating response signals.

36. An operational test device according claim 1, wherein

said converter device (WV) is designed

to control operatively the keypads and microphones of said telephones (T_n) by said programmable data processing device (S) by controlling further test instructions;

and

to convert response signals received from loudspeakers and call devices of said telephones (T_n) into digital operating response signals and to transmit them to said programmable data processing device (S) and to store them there.

37. An operational test device according to claim 1, wherein

said test device (TV) also comprises a connection device through which said converter device (WV) is connected to each of said telephones (T₁ -T_n), and through which said operating signals are transmitted from said converter device (WV) to selected telephones (T_n) and response signals are transmitted from telephones (T_n) dialed by these signals or from said selected telephones (T_n) to said converter device (WV).

38. An operational test device according to claim 37, wherein

said connection device comprises:

an adapter on said telephone connected to the telephone'"'"'s keypad, microphone, loudspeaker and call device; and

a detachable connection line provided between said adapter on said telephone and said converter device.

39. An operational test device according to claim 1, wherein

said converter device (WV) comprises a storage device, and data specific to the telephone and/or specific to the transmission station are stored in configuration files of said memory device of said converter device (WV), thereby adapting said converter device (WV) to different telephones and/or transmission stations (UEV).

40. An operational test device according to claim 1, wherein

said programmable data processing device (S) of said central signal processing device (ZV) is connected via a remote data transmission device (DFV) to a plurality of external programmable data processing devices (C₁ -C_n) and/or data display devices.

41. An operational test device according to claim 40, wherein

a local network (LAN) is provided for remote data transmission.

42. An operational test device according to claim 40, wherein

an internet connection is provided for remote data transmission.

43. An operational test device according to claim 1, wherein

said at least one interrupt device (UV) is arranged between contact strips (KL1) of at least one circuit card (SK) and contact strips (KL2) of a circuit card carrier (ST) of said transmission station (UEV).

44. An operational test device according to claim 43, wherein

a plurality of circuit cards is connected together in series and each comprises its own address, and that said circuit cards can be controlled via a single control line.

45. An operational test device according to claim 33, wherein

said at least one interrupt device (UV) is arranged on the respective front end of said circuit cards (SK) of said transmission station (UEV) connected to a circuit card carrier (ST).

46. An operational test device according to claim 1, wherein

said transmission station (UEV) is a GSM transmission station comprising a mobile services switching center (MSC), a base switching center (BSC) and a base transceiver station (BTS).

31. A method of executing an operational test (LT, DT, CT) for a test system (SUT) which has operating states corresponding to a real operating system (SUT-RA) used in a real operating environment, under test conditions, comprising the following steps:

a) generating a number of test cases (TC) with test commands which each indicate a predetermined change in operating state within said test system, having a test case generator (TCG);

b) receiving said test commands and outputting corresponding operating signals to said test system (SUT) for bringing about said predetermined changes in operating state via a test device interface (INT); and

c1) generating a state model of said test system from information on the hardware configuration of said test system (SUT), information on the possible operating states of said test system in a real application (SUT-RA), information on the test commands needed for bringing about changes in operating state within the test system (SUT), and from traffic values which indicate transitional probabilities ascertained in the test system'"'"'s real application for said operating states, having a test state model generator (TSTM-G, PNM-G);

c2) successively generating randomly controlled state changes according to said transitional probabilities within said test state model (TSTM) having a test state model simulator (TSTM-Sim, PNM-Sim); and

c3) generating test commands of said test cases (TC) on the basis of said state transitions generated by said test state model simulator (TSTM-Sim) and the test commands linked to these state transitions in accordance with said test state model (TSTM, PNM) as a result of a test state model command generator (TSTM-CG, PNM-CG).

32. A method according to claim 31, wherein

said operating signals are outputted as a test device interface (INT) via a device for executing test cases (TCE).

47. A method according to claim 31, wherein

said operational test (LT, DT, CT) is executed to test a test system (SUT) comprising a telephone communication device (KV) in an operative load condition, which contains a plurality of telephones (T₁ -T_n), particularly mobile telephones, a plurality of electrical connection lines and at least one transmission station (UEV) for transmitting signals within said telephone communication device (KV), wherein

said test device interface (INT) and said test case generator (TCG) form a test device (TV) for testing said telephone communication device (KV) in a load condition;

and

said method comprises the following steps;

generating and executing said test commands with a programmable data processing device (S) of a central signal processing device (ZV) of said test device (TV) for testing said telephone communication device (KV);

transmitting digital test signals generated according to said test commands to a converter device (WV) and converting said digital test signals into operating signals for systematically interrupting at least one electrical connection line of said plurality of electrical connection lines;

transmitting said operating signals from said converter device (WV) to an interrupt device (UV) and operationally controlling said interrupt device (UV) according to said operating signals to interrupt at least one electrical connection line for time intervals predetermined by said operating signals,

comparing the actual signal changes produced on account of said systematic interruptions with the associated reference signal changes and

signaling deviations of said actual signal changes from said reference signal changes.

48. A method according to claim 47, wherein the following steps are provided:

operationally controlling the keypads and microphones of said telephones by means of said converter device (WV) by controlling further test commands; and

receiving response signals from loudspeakers and call devices of said telephones and converting said response signals into digital operating signals, and transmitting said digital operating response signals to said programmable data processing device (S).

49. A method according to claim 47, wherein the following steps are provided:

setting up a voice channel between each pair of telephones of a plurality of telephones (T₁ to T_n) in a call involving two parties or a conference call involving three or more participants;

on the basis of said first telephone, repeatedly transmitting with a predetermined frequency via said voice channel a pattern of tone pulses that clearly identifies said first telephone;

having a second telephone participating in the call monitor the reception of said first telephone'"'"'s pattern of tone pulses transmitted via said voice channel;

wherein the transmission of said pattern of tone pulses between said first and second telephones includes voice compression and voice decompression; and

said pattern of tone pulses being selected such that an identification of said first telephone is possible when said pattern of tone pulses is received at said second telephone if voice compression and voice decompression are used.

50. A method according to one of the claims 47, wherein the following steps are provided:

transmitting operating signals from said converter device (WV) to telephones selected according to said test commands via a connection device; and

transmitting response signals of dialed telephones to said converter device via said connection device.

51. A method according to claim 47 wherein

data are transmitted via a remote data transmission device (DFV) between said programmable data processing device (S) of said test device (TV) and a plurality of external programmable data processing devices (C₁ -C_n) and/or data display devices.

52. An operational test device for executing an operational test (LT, DT, CT) for a test system (SUT) that has operating states corresponding to a real operating system (SUT-RA) used in a real operating environment, under test conditions, comprising:

a) a test case generator (TCG) for generating a number of test cases (TC) with test commands that are each intended to produce a desired change in operating state within said test system;

b) a test device interface (INT) for receiving said test commands and for outputting corresponding operating signals to the test system (SUT) for bringing about said desired changes in operating state;

c) said test case generator (TCG) comprising;

a test state model generator (TSTS-G, PNM-G) for generating a test state model of the test system (SUT) from information on the hardware configuration of the test system (SUT), information on the possible operating states of said real operating system (SUT-RA), from traffic values that indicate transitional probabilities ascertained during the real application of said operating system (SUT-RA) for said operating states, and from the permitted test commands of the test system (SUT);

a test state model store (TSTM-S, PNM-S) in which said test state model is stored;

a test state model simulator (TSTM-Sim, PNM-Sim) that statistically passes through said test state model and in doing so generates desired operating state transitions;

a test state model command generator (TSTM-CG, PNM-CG) for successively generating the test commands of said test cases (TC) on the basis of said operating state transitions generated by said test state model simulator; and

d) wherein said test device interface (INT) receives from said test system (SUT) operating response signals which each indicate a change in operating state executed in said test system as a response to the respective operating signal, and outputs corresponding operating response signals to said test case generator (TCG).

53. An operational test device for executing an operational test (LT, DT, CT) for a test system (SUT) that has operating states corresponding to a real operating system (SUT-RA) used in a real operating environment, under test conditions, comprising:

a) a test case generator (TCG) for generating a number of test cases (TC) with test commands that are each intended to produce a desired change in operating state within said test system;

b) a test device interface (INT) for receiving said test commands and for outputting corresponding operating signals to the test system (SUT) for bringing about said desired changes in operating state;

c) said test case generator (TCG) comprising;

a test state model generator (TSTS-G, PNM-G) for generating a test state model of the test system (SUT) from information on the hardware configuration of the test system (SUT), information on the possible operating states of said real operating system (SUT-RA), from traffic values that indicate transitional probabilities ascertained during the real application of said operating system (SUT-RA) for said operating states, and from the permitted test commands of the test system (SUT);

a test state model store (TSTM-S, PNM-S) in which said test state model is stored;

a test state model simulator (TSTM-Sim, PNM-Sim) that statistically passes through said test state model and in doing so generates desired operating state transitions;

a test state model command generator (TSTM-CG, PNM-CG) for successively generating the test commands of said test cases (TC) on the basis of said operating state transitions generated by said test state model simulator;

wherein

d) said test device interface (INT) receives from said test system (SUT) operating response signals which each indicate a change in operating state executed in said test system as a response to the respective operating signal, and outputs corresponding operating response signals to said test case generator (TCG); and

e) said test case generator (TCG) includes a comparer (CMP), said test state model simulator (TSTM-Sim, PNM-Sim) generating expected operating response signals of said test system (SUT) on the basis of said state model and storing them in a store (buffer B), storing the operating response signals generated by said test system (SUT) in response to the successively transmitted test commands in a store (buffer A), said comparer (CMP) comparing the operating response signals observed by said test system with expected operating response signals generated during simulation, and generating an error output when said stored expected and observed operating response signals do not match.

54. An operational test device for executing an operational test (LT, DT, CT) for a test system (SUT) that has operating states corresponding to a real operating system (SUT-RA) used in a real operating environment, under test conditions, comprising:

a) a test case generator (TCG) for generating a number of test cases (TC) with test commands that are each intended to produce a desired change in operating state within said test system;

b) a test device interface (INT) for receiving said test commands and for outputting corresponding operating signals to the test system (SUT) for bringing about said desired changes in operating state;

c) said test case generator (TCG) comprising;

a test state model generator (TSTS-G, PNM-G) for generating a test state model of the test system (SUT) from information on the hardware configuration of the test system (SUT), information on the possible operating states of said real operating system (SUT-RA), from traffic values that indicate transitional probabilities ascertained during the real application of said operating system (SUT-RA) for said operating states, and from the permitted test commands of the test system (SUT);

a test state model store (TSTM-S, PNM-S) in which said test state model is stored;

a test state model simulator (TSTM-Sim, PNM-Sim) that statistically passes through said test state model and in doing so generates desired operating state transitions;

a test state model command generator (TSTM-CG, PNM-CG) for successively generating the test commands of said test cases (TC) on the basis of said operating state transitions generated by said test state model simulator;

wherein

d) said test state model command generator (TSTM-CG, PNM-CG) passes through said test state model in a Monte-Carlo simulation in a random manner, but according to natural statistical rules; and

e) said test state model generator (PNM-G) generates a test state model of the test system (SUT) on the basis of a Petri net model (PNM).

55. An operational test device for executing an operational test (LT, DT, CT) for a test system (SUT) that has operating states corresponding to a real operating system (SUT-RA) used in a real operating environment, under test conditions, comprising:

a) a test case generator (TCG) for generating a number of test cases (TC) with test commands that are each intended to produce a desired change in operating state within said test system;

b) a test device interface (INT) for receiving said test commands and for outputting corresponding operating signals to the test system (SUT) for bringing about said desired changes in operating state;

c) said test case generator (TCG) comprising;

a test state model generator (TSTS-G, PNM-G) for generating a test state model of the test system (SUT) from information on the hardware configuration of the test system (SUT), information on the possible operating states of said real operating system (SUT-RA), from traffic values that indicate transitional probabilities ascertained during the real application of said operating system (SUT-RA) for said operating states, and from the permitted test commands of the test system (SUT);

a test state model store (TSTM-S, PNM-S) in which said test state model is stored;

a test state model simulator (TSTM-Sim, PNM-Sim) that statistically passes through said test state model and in doing so generates desired operating state transitions;

a test state model command generator (TSTM-CG, PNM-CG) for successively generating the test commands of said test cases (TC) on the basis of said operating state transitions generated by said test state model simulator;

wherein

d) said test state model command generator (TSTM-CG, PNM-CG) passes through said test state model in a Monte-Carlo simulation in a random manner, but according to natural statistical rules; and

e) the test system (SUT) is a telephone network and/or a mobile telephone network.

56. An operational test device for executing an operational test (LT, DT, CT) for a test system (SUT) that has operating states corresponding to a real operating system (SUT-RA) used in a real operating environment, under test conditions, comprising:

a) a test case generator (TCG) for generating a number of test cases (TC) with test commands that are each intended to produce a desired change in operating state within said test system;

b) a test device interface (INT) for receiving said test commands and for outputting corresponding operating signals to the test system (SUT) for bringing about said desired changes in operating state;

c) said test case generator (TCG) comprising;

a test state model generator (TSTS-G, PNM-G) for generating a test state model of the test system (SUT) from information on the hardware configuration of the test system (SUT), information on the possible operating states of said real operating system (SUT-RA), from traffic values that indicate transitional probabilities ascertained during the real application of said operating system (SUT-RA) for said operating states, and from the permitted test commands of the test system (SUT);

a test state model store (TSTM-S, PNM-S) in which said test state model is stored;

a test state model simulator (TSTM-Sim, PNM-Sim) that statistically passes through said test state model and in doing so generates desired operating state transitions;

a test state model command generator (TSTM-CG, PNM-CG) for successively generating the test commands of said test cases (TC) on the basis of said operating state transitions generated by said test state model simulator;

wherein

d) said test state model command generator (TSTM-CG, PNM-CG) passes through said test state model in a Monte-Carlo simulation in a random manner, but according to natural statistical rules;

e) the test system (SUT) is a telephone network and/or a mobile telephone network; and

f) said test case generator (TCG) transmits test commands for performing a load test (LT) by means of a load test command generator (LT-TCE) to a switching center (MSC) and/or local switching center (BSC) of a mobile telephone network.

57. An operational test device for executing an operational test (LT, DT, CT) for a test system (SUT) that has operating states corresponding to a real operating system (SUT-RA) used in a real operating environment, under test conditions, comprising:

a) a test case generator (TCG) for generating a number of test cases (TC) with test commands that are each intended to produce a desired change in operating state within said test system;

b) a test device interface (INT) for receiving said test commands and for outputting corresponding operating signals to the test system (SUT) for bringing about said desired changes in operating state;

c) said test case generator (TCG) comprising;

a test state model generator (TSTS-G, PNM-G) for generating a test state model of the test system (SUT) from information on the hardware configuration of the test system (SUT), information on the possible operating states of said real operating system (SUT-RA), from traffic values that indicate transitional probabilities ascertained during the real application of said operating system (SUT-RA) for said operating states, and from the permitted test commands of the test system (SUT);

a test state model store (TSTM-S, PNM-S) in which said test state model is stored;

a test state model simulator (TSTM-Sim, PNM-Sim) that statistically passes through said test state model and in doing so generates desired operating state transitions;

a test state model command generator (TSTM-CG, PNM-CG) for successively generating the test commands of said test cases (TC) on the basis of said operating state transitions generated by said test state model simulator;

wherein

d) said test state model command generator (TSTM-CG, PNM-CG) passes through said test state model in a Monte-Carlo simulation in a random manner, but according to natural statistical rules;

e) the test system (SUT) is a telephone network and/or a mobile telephone network; and

f) said test case generator (TCG) generates test commands for a conformance test (CT) by means of a conformance test command generator (CT-TCE) which controls a series of mobile telephones (MS) and an air interface simulator (AIS), and generates in this manner the user traffic of a mobile telephone network.

58. An operational test device for executing an operational test (LT, DT, CT) for a test system (SUT) that has operating states corresponding to a real operating system (SUT-RA) used in a real operating environment, under test conditions, comprising:

a) a test case generator (TCG) for generating a number of test cases (TC) with test commands that are each intended to produce a desired change in operating state within said test system;

b) a test device interface (INT) for receiving said test commands and for outputting corresponding operating signals to the test system (SUT) for bringing about said desired changes in operating state;

c) said test case generator (TCG) comprising;

a test state model generator (TSTS-G, PNM-G) for generating a test state model of the test system (SUT) from information on the hardware configuration of the test system (SUT), information on the possible operating states of said real operating system (SUT-RA), from traffic values that indicate transitional probabilities ascertained during the real application of said operating system (SUT-RA) for said operating states, and from the permitted test commands of the test system (SUT);

a test state model store (TSTM-S, PNM-S) in which said test state model is stored;

a test state model simulator (TSTM-Sim, PNM-Sim) that statistically passes through said test state model and in doing so generates desired operating state transitions;

a test state model command generator (TSTM-CG, PNM-CG) for successively generating the test commands of said test cases (TC) on the basis of said operating state transitions generated by said test state model simulator;

wherein

d) said test state model command generator (TSTM-CG, PNM-CG) passes through said test state model in a Monte-Carlo simulation in a random manner, but according to natural statistical rules;

e) the test system (SUT) is a telephone network and/or a mobile telephone network; and

f) said test case generator (TCG) generates test commands for a disturbance test (DT) by means of a disturbance test command generator (DT-TCE) which can systematically interrupt or disrupt lines between the switching centers of a mobile telephone network and/or can render inoperative or disrupt components within a switching center computer.

59. An operational test device for executing an operational test (LT, DT, CT) for a test system (SUT) that has operating states corresponding to a real operating system (SUT-RA) used in a real operating environment, under test conditions, comprising:

a) a test case generator (TCG) for generating a number of test cases (TC) with test commands that are each intended to produce a desired change in operating state within said test system;

b) a test device interface (INT) for receiving said test commands and for outputting corresponding operating signals to the test system (SUT) for bringing about said desired changes in operating state;

c) said test case generator (TCG) comprising;

a test state model generator (TSTS-G, PNM-G) for generating a test state model of the test system (SUT) from information on the hardware configuration of the test system (SUT), information on the possible operating states of said real operating system (SUT-RA), from traffic values that indicate transitional probabilities ascertained during the real application of said operating system (SUT-RA) for said operating states, and from the permitted test commands of the test system (SUT);

a test state model store (TSTM-S, PNM-S) in which said test state model is stored;

a test state model simulator (TSTM-Sim, PNM-Sim) that statistically passes through said test state model and in doing so generates desired operating state transitions;

a test state model command generator (TSTM-CG, PNM-CG) for successively generating the test commands of said test cases (TC) on the basis of said operating state transitions generated by said test state model simulator;

wherein

d) said test state model command generator (TSTM-CG, PNM-CG) passes through said test state model in a Monte-Carlo simulation in a random manner, but according to natural statistical rules;

e) said test state model generator (PNM-G) generates a test state model of the test system (SUT) on the basis of a Petri net model (PNM);

f) said test state model generator (TSTM-G) executed as a Petri net model generator (PNM-G) writes the generated Petri net state model of the test system (SUT) into a Petri net model store (PNM-S);

g) said test state model simulator (TSTM-Sim, PNM-Sim) is a Petri net model simulator (PNM-Sim) that contains a Petri net marking store (MSt) used to store a current operating state of said Petri net;

h) said Petri net model simulator (PNM-Sim) reads the current state of said Petri net model from said Petri net marking store (MSt) as a current marking of all the places with tokens (

), reads the Petri net state model (PNM) of said test system (SUT) from said Petri net model store (PNM-S), selects in a randomly controlled manner one of the possible state transitions given by the current marking and the structure of said Petri net model, calculates the new marking resulting from this state transition and stores it as a current marking in the marking store (MSt); and

i) said test state model command generator is a Petri net model command generator (PNM-CG) which is informed by said Petri net model simulator (PNM-Sim) about the performed transition, with the result that it loads from said Petri net model store (PNM-S) the corresponding test commands which constitute said generated test case, and passes them on to the test system (SUT).

60. An operational test device for executing an operational test (LT, DT, CT) for a test system (SUT) that has operating states corresponding to a real operating system (SUT-RA) used in a real operating environment, under test conditions, comprising:

a) a test case generator (TCG) for generating a number of test cases (TC) with test commands that are each intended to produce a desired change in operating state within said test system;

b) a test device interface (INT) for receiving said test commands and for outputting corresponding operating signals to the test system (SUT) for bringing about said desired changes in operating state;

c) said test case generator (TCG) comprising;

a test state model generator (TSTS-G, PNM-G) for generating a test state model of the test system (SUT) from information on the hardware configuration of the test system (SUT), information on the possible operating states of said real operating system (SUT-RA), from traffic values that indicate transitional probabilities ascertained during the real application of said operating system (SUT-RA) for said operating states, and from the permitted test commands of the test system (SUT);

a test state model store (TSTM-S, PNM-S) in which said test state model is stored;

a test state model simulator (TSTM-Sim, PNM-Sim) that statistically passes through said test state model and in doing so generates desired operating state transitions;

a test state model command generator (TSTM-CG, PNM-CG) for successively generating the test commands of said test cases (TC) on the basis of said operating state transitions generated by said test state model simulator;

wherein

d) said test state model command generator (TSTM-CG, PNM-CG) passes through said test state model in a Monte-Carlo simulation in a random manner, but according to natural statistical rules;

e) said test state model generator (PNM-G) generates a test state model of the test system (SUT) on the basis of a Petri net model (PNM);

f) said test state model generator (TSTM-G) executed as a Petri net model generator (PNM-G) writes the generated Petri net state model of the test system (SUT) into a Petri net model store (PNM-S);

g) said test state model simulator (TSTM-Sim, PNM-Sim) is a Petri net model simulator (PNM-Sim) that contains a Petri net marking store (MSt) used to store a current operating state of said Petri net;

h) said Petri net model simulator (PNM-Sim) reads the current state of said Petri net model from said Petri net marking store (MSt) as a current marking of all the places with tokens (

), reads the Petri net state model (PNM) of said test system (SUT) from said Petri net model store (PNM-S), selects in a randomly controlled manner one of the possible state transitions given by the current marking and the structure of said Petri net model, calculates the new marking resulting from this state transition and stores it as a current marking in the marking store (MSt);

i) said test state model command generator is a Petri net model command generator (PNM-CG) which is informed by said Petri net model simulator (PNM-Sim) about the performed transition, with the result that it loads from said Petri net model store (PNM-S) the corresponding test commands which constitute said generated test case, and passes them on to the test system (SUT);

j) said test state model store (TSTM-S, PNM-S) is a Petri net model store (PNM-S) which is provided for storing

places (◯

) of said Petri net, said places indicating the possible operating states of individual operating means, services or components of said test system (SUT);

transitions (|) of said Petri net, said transitions describing the possible changes in state within said state model and including the operational function to be executed in the form of actions; and

edges (→

) which connect places to transitions and transitions to edges and which indicate the conditions that have to be satisfied before or after a transition is switched, wherein these conditions are given by that marking of the places connected to the transition via edges which is necessary for said transition and results therefrom; and

an initial marking of the places of said Petri net state model (PNM), comprising tokens (

) that specify the model'"'"'s initial state before starting the simulation or test case generation.

61. An operational test device for executing an operational test (LT, DT, CT) for a test system (SUT) that has operating states corresponding to a real operating system (SUT-RA) used in a real operating environment, under test conditions, comprising:

a) a test case generator (TCG) for generating a number of test cases (TC) with test commands that are each intended to produce a desired change in operating state within said test system;

b) a test device interface (INT) for receiving said test commands and for outputting corresponding operating signals to the test system (SUT) for bringing about said desired changes in operating state;

c) said test case generator (TCG) comprising;

a test state model generator (TSTS-G, PNM-G) for generating a test state model of the test system (SUT) from information on the hardware configuration of the test system (SUT), information on the possible operating states of said real operating system (SUT-RA), from traffic values that indicate transitional probabilities ascertained during the real application of said operating system (SUT-RA) for said operating states, and from the permitted test commands of the test system (SUT);

a test state model store (TSTM-S, PNM-S) in which said test state model is stored;

a test state model simulator (TSTM-Sim, PNM-Sim) that statistically passes through said test state model and in doing so generates desired operating state transitions;

a test state model command generator (TSTM-CG, PNM-CG) for successively generating the test commands of said test cases (TC) on the basis of said operating state transitions generated by said test state model simulator;

wherein

d) said test state model command generator (TSTM-CG, PNM-CG) passes through said test state model in a Monte-Carlo simulation in a random manner, but according to natural statistical rules;

e) said test device interface (INT) receives from said test system (SUT) operating response signals which each indicate a change in operating state executed in said test system as a response to the respective operating signal, and outputs corresponding operating response signals to said test case generator (TCG);

f) said test state model generator (TSTM-G) executed as a Petri net model generator (PNM-G) writes the generated Petri net state model of said test system (SUT) into a Petri net model store (PNM-S);

g) said test state model simulator (TSTM-Sim, PNM-Sim) is a Petri net model simulator (PNM-Sim) that contains a Petri net marking store (MSt) used to store a current operating state of said Petri net;

h) said Petri net model simulator (PNM-Sim) reads the current state of said Petri net model from said Petri net marking store (MSt) as a current marking of all the places with tokens (

), reads the Petri net state model (PNM) of said test system (SUT) from said Petri net model store (PNM-S), selects in a randomly controlled manner one of the possible state transitions given by the current marking and the structure of said Petri net model, calculates the new marking resulting from this state transition and stores it as a current marking in the marking store (MSt);

i) said test state model command generator is a Petri net model command generator (PNM-CG) which is informed by said Petri net model simulator (PNM-Sim) about the performed transition, with the result that it loads from said Petri net model store (PNM-S) the corresponding test commands which constitute said generated test case, and passes them on to the test system (SUT); and

wherein

said test case generator (TCG) further comprises;

a signal handler (PNM-SH) for receiving said operating response signals, for detecting a current change in state of the test system (SUT) from said operating response signals, and for outputting a current change in state in the form of tokens to said Petri net marking store (MSt) for synchronizing the current state of said Petri net to the current operating state of said test system (SUT).

62. An operational test device for executing an operational test (LT, DT, CT) for a test system (SUT) that has operating states corresponding to a real operating system (SUT-RA) used in a real operating environment, under test conditions, comprising:

a) a test case generator (TCG) for generating a number of test cases (TC) with test commands that are each intended to produce a desired change in operating state within said test system;

b) a test device interface (INT) for receiving said test commands and for outputting corresponding operating signals to the test system (SUT) for bringing about said desired changes in operating state;

c) said test case generator (TCG) comprising;

a test state model generator (TSTS-G, PNM-G) for generating a test state model of the test system (SUT) from information on the hardware configuration of the test system (SUT), information on the possible operating states of said real operating system (SUT-RA), from traffic values that indicate transitional probabilities ascertained during the real application of said operating system (SUT-RA) for said operating states, and from the permitted test commands of the test system (SUT);

a test state model store (TSTM-S, PNM-S) in which said test state model is stored;

a test state model simulator (TSTM-Sim, PNM-Sim) that statistically passes through said test state model and in doing so generates desired operating state transitions;

a test state model command generator (TSTM-CG, PNM-CG) for successively generating the test commands of said test cases (TC) on the basis of said operating state transitions generated by said test state model simulator;

wherein

d) said test state model command generator (TSTM-CG, PNM-CG) passes through said test state model in a Monte-Carlo simulation in a random manner, but according to natural statistical rules;

e) said test state model generator (PNM-G) generates a test state model of the test system (SUT) on the basis of a Petri net model (PNM);

f) said test state model generator (TSTM-G) executed as a Petri net model generator (PNM-G) writes the generated Petri net state model of the test system (SUT) into a Petri net model store (PNM-S);

g) said test state model simulator (TSTM-Sim, PNM-Sim) is a Petri net model simulator (PNM-Sim) that contains a Petri net marking store (MSt) used to store a current operating state of said Petri net;

h) said Petri net model simulator (PNM-Sim) reads the current state of said Petri net model from said Petri net marking store (MSt) as a current marking of all the places with tokens (

), reads the Petri net state model (PNM) of said test system (SUT) from said Petri net model store (PNM-S), selects in a randomly controlled manner one of the possible state transitions given by the current marking and the structure of said Petri net model, calculates the new marking resulting from this state transition and stores it as a current marking in the marking store (MSt);

i) said test state model command generator is a Petri net model command generator (PNM-CG) which is informed by said Petri net model simulator (PNM-Sim) about the performed transition, with the result that it loads from said Petri net model store (PNM-S) the corresponding test commands which constitute said generated test case, and passes them on to the test system (SUT);

j) said test state model store (TSTM-S, PNM-S) is a Petri net model store (PNM-S) which is provided for storing

places (◯

) of said Petri net, said places indicating the possible operating states of individual operating means, services or components of said test system (SUT);

transitions (|) of said Petri net, said transitions describing the possible changes in state within said state model and including the operational function to be executed in the form of actions;

edges (→

) which connect places to transitions and transitions to edges and which indicate the conditions that have to be satisfied before or after a transition is switched, wherein these conditions are given by that marking of the places connected to the transition via edges which is necessary for said transition and results therefrom;

an initial marking of the places of said Petri net state model (PNM), comprising tokens (

) that specify the modells initial state before starting the simulation or test case generation;

k) said signal handler (PNM-SH) generates from the information on the hardware configuration a number of tokens (

) which each indicate an operating means available within said test system or a state thereof (auto-configuration); and

1) said Petri net model store (PNM-S) comprises a predetermined number of synchronization places (), wherein a transition (|) connected to such a synchronization place () and if necessary to other places (◯

) via input edges can only be fired when said signal handler (PNM-SH) announces a change in state within the test system (SUT) via this synchronization place () within said Petri net state model in that on account of a response operating signal, said signal handler places a token into said synchronization place ().

63. An operational test device for executing an operational test (LT, DT, CT) for a test system (SUT) that has operating states corresponding to a real operating system (SUT-RA) used in a real operating environment, under test conditions, comprising:

a) a test case generator (TCG) for generating a number of test cases (TC) with test commands that are each intended to produce a desired change in operating state within said test system;

b) a test device interface (INT) for receiving said test commands and for outputting corresponding operating signals to the test system (SUT) for bringing about said desired changes in operating state;

c) said test case generator (TCG) comprising;

a test state model generator (TSTS-G, PNM-G) for generating a test state model of the test system (SUT) from information on the hardware configuration of the test system (SUT), information on the possible operating states of said real operating system (SUT-RA), from traffic values that indicate transitional probabilities ascertained during the real application of said operating system (SUT-RA) for said operating states, and from the permitted test commands of the test system (SUT);

a test state model store (TSTM-S, PNM-S) in which said test state model is stored;

a test state model simulator (TSTM-Sim, PNM-Sim) that statistically passes through said test state model and in doing so generates desired operating state transitions;

a test state model command generator (TSTM-CG, PNM-CG) for successively generating the test commands of said test cases (TC) on the basis of said operating state transitions generated by said test state model simulator;

wherein

d) said test state model command generator (TSTM-CG, PNM-CG) passes through said test state model in a Monte-Carlo simulation in a random manner, but according to natural statistical rules;

e) the test system (SUT) is a telephone network and/or a mobile telephone network;

f) said test state model store (TSTM-S, PNM-S) is a Petri net model store (PNM-S) which is provided for storing

places (◯

) of said Petri net, said places indicating the possible operating states of individual operating means, services or components of said test system (SUT);

transitions (|) of said Petri net, said transitions describing the possible changes in state within said state model and including the operational function to be executed in the form of actions;

edges (→

) which connect places to transitions and transitions to edges and which indicate the conditions that have to be satisfied before or after a transition is switched, wherein these conditions are given by that marking of the places connected to the transition via edges which is necessary for said transition and results therefrom;

an initial marking of the places of said Petri net state model (PNM), comprising tokens (

) that specify the model'"'"'s initial state before starting the simulation or test case generation;

g) said tokens (

) represent the subscribers of the telephone network, connections between them, other network services used by them, and/or timers;

h) said places (◯

) indicate the states which can be assumed by said subscribers, connections between said subscribers, telephone network services used by said subscribers, or timers within said test system (SUT); and

i) said transitions (|) represent operational functions by which said subscribers within said net can produce a change in state, or reflect changes in state of the subscribers themselves.