JPH09233150A - Sequence chart generating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To generate a sequence chart including a signal state or the like on the way of transmission efficiently by storing a mark to a part at which occurrence of a transmission line fault is predicted onto a normal system sequence chart and inserting a quasi-normal system sequence chart to the position. SOLUTION: A sequence chart is given to an input section 21 to input a normal system in a communication protocol to a description section 22. Data of corresponding protocol description from a charge generating section 24 are read from a database 25. A mark is given to a part where occurrence of a transmission line fault is predicted in the chart described by the normal system protocol and the result is stored in the database 25. When no signal is received due to occurrence of a fault, a quasi-normal system is given to a quasi-normal description section 23. After analysis of protocol logic, when the quasi-normal system is inserted to the normal system, the mark is detected from the chart and the quasi-normal system protocol is inserted to the position. As a result the description of the quasi-normal system is set formally similarly to the case with the normal system.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sequence chart creating device used in the development process of communication software.

[0002]

2. Description of the Related Art In recent years, a computer-aided software development environment has been actively studied in developing communication software, and it is desired to efficiently design a high-quality communication protocol.

Generally, when designing a communication protocol between a center station and a terminal, a designer creates a sequence chart showing the exchange of signals between the center station and the terminal with a sequence chart creating device. The sequence chart is a chart in which the processes that are communication entities and the signals transmitted and received between the processes are expressed over time.

By the way, when the communication system to be designed is, for example, a wireless communication system or a CATV system,
The bit error rate (BER) on the transmission line significantly increases due to noise or rainfall.

In this case, even if a signal is transmitted from the transmitting side, it may not reach the receiving side.

On the receiving side, unless some signal arrives,
It may not be possible to determine whether or not a signal has been transmitted from the transmitting side, and as a result, a state may occur in which the signal disappears on the transmission path. Therefore, even when creating a sequence chart, it is necessary to accurately represent the above-mentioned signal loss on the chart.

However, conventionally, the expression rules of a message sequence chart (MSC) have not standardized the method of describing a quasi-normal system such as signal loss, and for example, it is connected to a certain process P via a transmission line. In order to represent the exchange of signals with the other process Q that has been processed by a sequence chart, for example, as a normal system description, FIG.
As shown in (a), when the signal X is transmitted from the process P to the process Q, the disappearance of the signal X is as shown in FIG.
As shown in (b), the arrow of the signal X from the process P to the process Q is interrupted midway, and an "x" mark is written there.

In this way, the signal X is transmitted from the process P to the process Q, but the expression is such that the signal Q cannot be received by the process Q due to a transmission path failure (signal loss expression).
Is not specified in the expression rules of the MSC, and conventionally, each designer expressed it in an informal form, that is, in an original form of expression.

By the way, when each designer uses the sequence chart creating apparatus, after creating the sequence chart, the description of the graphical sequence chart is automatically converted into the text format to study the protocol, or the source program is used. Often converted to.

Therefore, if the protocol can be described by a general-purpose sequence chart, the designer does not have to be aware of the text format, but the protocol description / verification / verification
Program conversion etc. can be performed.

On the other hand, if even a part of the created sequence chart is described in an informal form, the conversion to the text format is left to the designer himself, and the workload of the designer increases only by that. Not only that, but the design efficiency is also significantly reduced.

Furthermore, the more informal the sequence chart is, the more the expression is different from other designers. As a result, the protocol description is not correctly understood by other designers, and it is based on the sequence chart. The communication protocol may not be designed correctly.

[0013]

As described above, in the conventional sequence chart creating apparatus, when a sequence chart is created, each designer does not give an expression that a signal is lost due to a transmission path failure or the like. Since it was written in the official form, the protocol of the created sequence chart is verified and the sequence chart is given the specified code,
In other words, when converting to the text format, the designer who created the sequence chart must do it by himself, and there is a problem that the work load of the designer increases and the work efficiency significantly decreases.

When a plurality of designers jointly design a protocol, each designer describes in a unique expression form because the expression of a quasi-normal system protocol such as signal loss on a sequence chart is informal. There are also problems that other designers do not correctly understand the protocol description of the sequence chart and that the protocol design is not performed correctly.

Therefore, the present invention has been made in order to solve such a problem. The description of the quasi-normal system protocol is also made into a formal expression form, and the normal system protocol of the communication software, the quasi-normal system protocol, It is possible to efficiently create a sequence chart including signal states during transmission. An object is to provide a sequence chart creation device.

[0016]

In order to solve the above-mentioned problems, the sequence chart creating apparatus according to the first aspect of the invention creates a sequence chart which is a communication procedure of signals exchanged between a plurality of processes. In the sequence chart creating device, there is an input unit for inputting the sequence chart, and a normal system sequence chart described in the normal system protocol and the normal system protocol while the sequence chart is being input by the input unit. Not creating a quasi-normal system sequence chart described in quasi-normal system protocol, and a chart creating means for recording a mark at a position where irregularity is expected to occur on the normal system sequence chart,
A normal system chart storing means for storing a normal system sequence chart created by the sequence chart creating means; a quasi-normal system chart storing means for storing a quasi-normal system sequence chart created by the sequence chart creating means; Mark detection means for reading the normal system sequence chart from the system chart storage means to detect the presence or absence of the mark on the chart, and the semi-normal at the position on the normal system sequence chart where the mark is detected by the marking detection means. And a chart inserting means for inserting the quasi-normal system sequence chart of the system chart storing means.

In the case of the invention according to claim 1, when the sequence chart is input by the sequence chart input means, the normal sequence chart described in the normal protocol and the quasi-normal protocol not present in the normal protocol are described. And the quasi-normal system sequence chart are created and stored in the respective chart storage means. Here, marks are recorded on the normal system sequence chart at positions where irregularities are predicted to occur.

When verifying the sequence chart, when the normal sequence chart is read from the normal chart storing means by the marking detecting means and a mark is detected on the chart, the mark is quasi-normal at that position. A system sequence chart is inserted. Since the quasi-normal system sequence chart is stored in the quasi-normal system chart storing means and the same description can be used any number of times, the description of the quasi-normal system can be unified. Therefore, a sequence chart including a normal protocol and a quasi-normal protocol can be efficiently created.

According to a second aspect of the present invention, there is provided the sequence chart creating apparatus according to the first aspect, wherein the chart creating means uses the transmission line as one process to form the normal sequence chart and the quasi-normal sequence chart. It is characterized by creating.

According to the second aspect of the present invention, since the normal system sequence chart and the quasi-normal system sequence chart are created by using the transmission line as one process, even the state of the signal during transmission is formalized on the sequence chart. Can be described in.

A sequence chart creating apparatus according to a third aspect of the present invention includes a transmission path process setting means for setting a transmission path process between a plurality of processes, and a transmission path process set by the transmission path process setting means. A normal description means for describing a sequence chart between a plurality of processes by a normal system protocol, a transmission path status verification means for verifying the protocol status of the sequence chart described by the normal description means, and a verification result of the transmission path status verification means. When there is a place where a protocol abnormality is predicted to occur, an abnormality description means for describing a sequence chart with a quasi-normal system protocol for that location, and a sequence chart described by the abnormality description means for the normal description means The chart to be inserted at the corresponding position on the sequence chart described by It is characterized by comprising a preparative insertion means.

In the third aspect of the present invention, the transmission line process setting means sets the transmission line process among a plurality of processes. Then, a sequence chart between a plurality of processes via the transmission line process is described by a normal protocol. In the described sequence chart, the protocol status is verified by the transmission path status verification means. As a result of the verification, if there is a place where a protocol abnormality is predicted to occur, a sequence chart is described by the anomaly description means in the quasi-normal system protocol, and this quasi-normal system sequence chart is a normal system by the chart insertion means. It is inserted at the corresponding position on the sequence chart.

Therefore, when designing a communication protocol between a plurality of processes, it is possible to create a total sequence chart including signal states during transmission.

If necessary, a reachability analysis technique or the like is introduced to the sequence chart completed by the protocol description of the normal system and the quasi-normal system, and protocol logic contradiction analysis such as deadlock is performed. It is also possible to generate code automatically.

By this, when there is a possibility that a failure or signal loss will occur on the transmission line, these can be described in a formal form on the sequence chart, and as a result, the protocol description, protocol verification, code generation, etc. can be efficiently performed. It can be carried out.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram showing one embodiment of a sequence chart creating apparatus according to the present invention, and FIG. 2 is a diagram showing each sequence chart created by this sequence chart creating apparatus.

In FIG. 1, 1a is a keyboard as an input means. 1b is a CRT as an output means. A computer body 2 includes a sequence chart input unit 21 for inputting operations from the keyboard 1a as a sequence chart, a normal system description unit 22 for inputting a normal communication protocol through the sequence chart input unit 21, and a sequence chart input unit 21. For example, a quasi-normal description section 23 into which a quasi-normal protocol is input when an expected signal does not come from the other party, and the quasi-normal protocol of the quasi-normal description section 13 is sent to the normal protocol description section of the normal system description section 22 as desired It is composed of a sequence chart creation unit 24 for inserting and creating a sequence chart summarizing the quasi-normal system and the normal system, a database 25 in which protocol data of the quasi-normal description unit 23 and the normal system description unit 22 are stored. .

The operation of this sequence chart creating apparatus will be described below.

In the case of this sequence chart creating device,
When the sequence chart is input to the sequence chart input unit 21 by the operation from the keyboard 1a, the normal system of the communication protocol is input to the normal system description unit 22 from the sequence chart input unit 21. Then, the sequence chart creation unit 24 reads the data of the corresponding protocol description from the database 25 and displays it on the CRT 1b. This is repeated to create a sequence chart. That is, as shown in FIG. 2A, a normal system protocol in which a signal X is transmitted from the process P to the process Q and a response signal A is transmitted from the process Q to the process P between the process P and the process Q. Sequence chart is created.

Here, in the sequence chart described in the normal system protocol, a mark C is attached to a portion where a failure is expected to occur on the transmission path.

The normal system sequence chart created in this manner is stored in the database 25.

Subsequently, when a quasi-normal system input operation is performed from the keyboard 1a when a signal expected from another process does not come due to the occurrence of a transmission path failure or the like, the quasi-normality description section 23 receives the quasi-normality description section 23 and takes action. The data of the protocol description to be read is read from the database 25 and displayed on the CRT 1b. That is, as shown in FIG. 2B, a quasi-normal system process in which the response signal A is not received by the process P on the receiving side, a timeout occurs in the process P, and the signal X is retransmitted to the process Q. Describe. The sequence chart of the quasi-normal system process created in this way is stored in the database 25.

Next, the sequence chart creating section 24 reads the created sequence chart of the normal system from the database 25, and actually uses a reachability analysis to determine whether there is a protocol logic contradiction such as deadlock. To check.

As a result of this check, if an error is detected, the process returns to the sequence chart input section 21 and the input is performed again. All the elements (protocol description data) are stored in the database 25 and read from the database 25.

When a quasi-normal system is inserted into the normal system from the keyboard 1a after the protocol logic inconsistency analysis, the sequence chart creation unit 24 detects the mark C from the sequence chart described in the normal system protocol. Then, as shown in FIG. 2C , the sequence chart of the process C described by the quasi-normal system protocol is inserted at the position of the mark C of the normal system sequence chart. This processing C includes loop processing,
The loop process is a resend process due to a timeout.

As a result, the data of the quasi-normal system protocol is inserted at the place where the occurrence of a transmission path failure or the like is predicted, and the sequence chart with these failures taken into account is completed. That is, the normal system and the quasi-normal system can be described in a formal form on one sequence chart.

As described above, according to the sequence chart creating apparatus of this embodiment, when designing the communication protocol between the processes P and Q, the sequence chart is described by the normal system protocol, and in addition to this, a transmission line failure or the like is caused. By writing a detailed sequence chart of the quasi-normal system and inserting it into the normal system protocol, the description of the quasi-normal system can be officially inserted at the predicted occurrence point (position of mark C) of a transmission line failure. . As a result, the description of the quasi-normal system can be formalized like the normal system, and even a person other than the sequence chart creator can perform subsequent code generation work without misunderstandings or mistakes.

Next, a sequence chart creating apparatus of another embodiment will be described with reference to FIGS. 3 and 4.
FIG. 3 is a diagram showing a configuration in which the sequence chart creating device of the present invention is applied to an actual transmission line fault, and FIG. 4 is a diagram showing an example expressing a case where a signal is lost due to the transmission line fault.

In FIG. 3, reference numeral 31 is a transmission line process setting unit, and when a new process M representing a transmission line is input from the sequence chart input unit 21, processes P and Q are entered.
In the meantime, a new process M is set. Reference numeral 32 is a transmission line state verification unit, which verifies whether or not the state of the transmission line is normal. 3
Reference numeral 3 is a transmission line normality description part, which describes a protocol when the transmission line state verification result is normal. Reference numeral 34 is a transmission line abnormality description part, and when the transmission line state verification result by the transmission line state verification part 32 is abnormal, the sequence chart of that portion is described by a semi-normal protocol. Reference numeral 35 denotes a sequence chart creation unit that creates a sequence chart from the chart data input by the input operation of the keyboard 1a and, if necessary, changes the sequence chart described by the transmission path abnormality description unit 34 to a normal protocol. Insert it in the corresponding part of the described sequence chart.

In the case of this sequence chart creating device,
When the transmission line process setting operation is performed with the keyboard 1a, a request for setting a new process M representing a transmission line is issued from the sequence chart input unit 21 to the transmission line process setting unit 31.
And the process of the transmission line is set between the plurality of processes by the transmission line process setting unit 31.

Subsequently, when chart data is input from the keyboard 1a, the sequence chart creating section 35 describes / creates a sequence chart using a normal protocol. Here, the mark C is recorded at a location where an abnormality has occurred in the normal sequence chart.

When the normal system sequence chart is created, the transmission line state verification unit 32 verifies the transmission line state.

Here, when the state of the transmission path is normal, the transmission path normality description section 33 describes a sequence chart (normal system sequence chart) in which the process of the transmission path is interposed by the normal system protocol.

As a result of the transmission line status verification, the transmission line abnormality description section 3 is used for the place where an abnormality is predicted to occur in the transmission line.
4 describes a sequence chart (quasi-normal system sequence chart) in which a process of a transmission path is interposed by a quasi-normal system protocol.

If necessary, that is, when the sequence chart input unit 21 is operated to insert (synthesize) a chart, the sequence chart creation unit 35 produces the quasi-normal system sequence chart described in the transmission path abnormality description unit 34. , Is inserted at the position of mark C in the normal sequence chart. This makes it possible to describe all the cases where the transmission path is normal or abnormal.

After the sequence chart is actually created in this way, the sequence chart creating section 35 analyzes the logical inconsistency of the protocol such as deadlock by reachability analysis and checks it. If an error is detected here,
The chart is re-input from the sequence chart input unit 21.

Here, a concrete example of the above-mentioned operation, that is, a signal does not reach due to the occurrence of a transmission path failure (signal loss)
The expression in the case will be described.

For example, when the signal X is transmitted from the process P to the process Q, between the process P and the process Q,
A process line M representing a transmission line is set.

First, when the transmission line with no signal loss is normal, as shown in FIG. 4A, the signal X is transmitted from the process P to the process M, and the result of the transmission line state verification is <O.
In the case of K>, the signal X is transmitted from the process M to the process Q, and such a normal system is described.

On the other hand, when there is a transmission line failure and there is a signal loss during transmission, the signal X is transmitted from the process P to the process M as shown in FIG. 4B, but the result of the transmission line state verification is <NG>, process M to process Q
The signal X is not transmitted to, and the description becomes such a quasi-normal system.

An example of communication protocol design in a specific communication system will be described below with reference to FIG. FIG. 5 is an example of communication protocol design for a wireless communication system, a two-way CATV system, or the like.

In this example, when there is an off-hook at the terminal 51, the request signal (Re
q), the vacant channel is allocated in the center station 52, the allocation signal is transmitted from the center station 52 to the terminal 51, and the request signal does not reach the center station 52 in the terminal 51, resulting in the allocation signal. In this example, if the request signal (Req) is not sent from the center station 52, the request signal (Req) is transmitted again from the terminal 51 to the center station 52.

In this case, first, as shown in FIG. 5A, a normal system sequence chart when there is no signal loss will be described.

That is, when the terminal 51 is off-hook, the request signal (Req) is sent from the terminal 51 to the process M.
Send Here, the transmission line state is verified.

In this case, since the verification result is OK, the request signal (Req) from the process M to the center station 52.
Is transmitted and the allocation signal is transmitted from the center station 52 to the terminal 51.

Next, the mark C is recorded after transmitting the request signal (Req) from the terminal 51 to the process M, that is, the part for performing the quasi-normal system process when the allocation signal does not come.

Then, for the quasi-normal system processing within this mark C, after transmitting the request signal (Req) from the terminal 51, a timer is started as shown in FIG. Since the verification result is NG, as a result, the terminal 51 cannot receive the allocation signal, a time-out occurs on the terminal 51 side, the request signal (Req) is transmitted to the process M again, and the timer is started. The sequence chart is described by the transmission path abnormality description unit 34.

Then, when synthesizing the sequence charts, as in the first embodiment, the sequence chart of the quasi-normal system processing described by the transmission path abnormality description unit 34 is added to the portion of the mark C on the sequence chart of FIG. 5A. When inserted, a sequence chart including a sequence chart C of the quasi-normal system process as shown in FIG. 5C is completed. The process of the sequence chart C includes a retransmission process (loop process) due to a timeout, and a symbol "loop" is added.

Also in this case, if the result of the transmission path state verification in the process M is OK, the process M is transferred to the center station 5
2, the request signal (Req) is transmitted, and as a result, the allocation signal is transmitted from the center station 52 to the terminal 51. Hereinafter, the retransmission processing of the allocation signal when the response signal from the terminal 51 to the allocation signal of the center station 52 does not come will be similarly described.

As described above, according to the sequence chart creating apparatus of this embodiment, the process M of the transmission line is set between the processes P and Q, and the process P through the process M
When the transmission state between Q is verified and a transmission error occurs, a sequence chart is described for that location using a quasi-normal protocol, and the sequence chart is inserted into the already created normal system sequence chart so that between processes P and Q. It becomes possible to accurately describe the sequence chart including the case where the transmission abnormality occurs due to the exchange of the signal X.

[0062]

As described above, according to the present invention, a mark is recorded at a position where irregularity is expected to occur on a normal system sequence chart, and the marking detecting means is used when verifying the sequence chart. When the mark is detected by, the quasi-normal system sequence chart is inserted at that position, so that the same quasi-normal system description can be used many times and the quasi-normal system description can be unified. Further, since the normal system sequence chart and the quasi-normal system sequence chart are created by using the transmission path as one process, even the state of a signal during transmission can be described in a formal form on the sequence chart.

As a result, the description of the quasi-normal system protocol can be made formal, and the sequence chart including the normal system protocol of the communication software, the quasi-normal system protocol, the signal state during transmission, etc. can be efficiently created. it can.

[Brief description of drawings]

FIG. 1 is a diagram showing a sequence chart creation device according to an embodiment of the present invention.

FIG. 2A is a diagram showing an example of a sequence chart described in a normal protocol. FIG. 6B is a diagram showing an example of a sequence chart described in a quasi-normal system protocol.
FIG. 6C is a diagram showing an example in which a quasi-normal sequence chart is inserted into a normal sequence chart.

FIG. 3 is a diagram showing a sequence chart creation device according to another embodiment of the present invention.

FIG. 4A is a verification result of the process M on the transmission line, OK.
The figure which shows the sequence chart in the case of. FIG. 9B is a diagram showing a verification result of the process M on the transmission path, and a sequence chart in the case of NG.

FIG. 5A is a diagram showing an example of a normal system sequence chart created by applying it to actual communication. (B) The figure which shows the example of description of the quasi-normal system sequence chart in the mark C. (C) The figure which shows the state which inserted the quasi-normal system sequence chart in the mark C position of a normal system sequence chart.

FIG. 6A is a diagram showing an example of a normal system protocol description by a conventional sequence chart creation device. (B) The figure which shows the quasi-normal system protocol description example by the conventional sequence chart preparation apparatus.

[Explanation of symbols]

1a ... keyboard, 1b ... CRT, 2 ... computer main body, 21 ... sequence chart input section, 22 ... normal system description section, 23 ... quasi-normal description section, 24 ... sequence chart creation section, 25 ... database.

Claims (3)

[Claims] 1. A sequence chart creating apparatus for creating a sequence chart, which is a communication procedure of signals exchanged between a plurality of processes, wherein an input means for inputting the sequence chart, and the sequence chart by the input means. While inputting, create a normal sequence chart described in a normal protocol and a quasi-normal sequence chart described in a quasi-normal system protocol that does not exist in the normal protocol, and add it to the normal sequence chart. A chart creating means for recording a mark at a position where irregularity is expected to occur, a normal system chart storing means for storing a normal system sequence chart created by the sequence chart creating means, and a sequence chart creating means Quasi-normal Quasi-normal system chart storage means for storing a sequence chart, mark detection means for reading out the normal system sequence chart from the normal system chart storage means and detecting the presence or absence of the mark on the chart, and the mark detection means for detecting the mark A sequence chart creating device comprising: a chart inserting unit that inserts a quasi-normal system sequence chart of the quasi-normal system chart storing unit at a position on the normal system sequence chart. 2. The sequence chart creating apparatus according to claim 1, wherein the chart creating means creates the normal sequence chart and the quasi-normal sequence chart using the transmission line as one process. 3. A transmission path process setting means for setting a transmission path process between a plurality of processes, and a sequence chart between the plurality of processes via the transmission path process set by the transmission path process setting means, showing a normal protocol. The normal description means described in 1., the transmission path status verification means for verifying the protocol status of the sequence chart described by the normal description means, the verification result of the transmission path status verification means, and the location where the protocol abnormality is predicted to occur If it exists, the anomaly description means that describes the sequence chart with the quasi-normal system protocol for that location, and the sequence chart described by the anomaly description means to the corresponding location on the sequence chart described by the anomaly description means. And a chart insertion means for inserting the chart. Scan chart creation device.