JPH11215241A - Network communication system and its controlling storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a network communication system and a storage medium to realize the system where communication is restarted as early as possible without aborting normal communication information from a communication destination till the restart of communication after interrupted communication with the communication destination. SOLUTION: This system is provided with a 1st exchange station 50 and a 2nd exchange station 51 that conduct transmission/reception of a signal message and the 1st exchange station 50 and the 2nd exchange station 51 are interconnected by a signal channel 52. The 1st exchange station 50 (2nd exchange station 51) has a SCCP (54) that controls a non-channel corresponding signal, a sub system state denoting whether or not a communication enable signal corresponds to a sub system of an object station and a restart information denoting whether or not communication restart is just finished. At the restart of communication, the restart information is set to denote that the communication has just restarted and a prescribed test signal is sent to each subsystem of all object stations. In the case that a restart flag of the sib system of a corresponding object station is set to be a state of communication restart just finished depending on a reply signal with respect to the test signal, the communication having been made before interruption is restarted for this sub system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a network communication system for transmitting and receiving call information and a control signal for controlling the call information in order to provide each service, and a control storage medium therefor. The present invention relates to a network communication system in which a signal discarded when communication is resumed after being interrupted is reduced, and a control storage medium therefor.

[0002]

2. Description of the Related Art In recent years, in response to a demand for the advancement of a telephone switching network service, an integrated service digital network (Integrated
Services Digital Network: Abbreviated as ISDN. ) Has been realized. ISDN is a communication network constructed by digital technology, and transmits and receives signals between nodes in the communication network in response to various service requests from various terminals accommodated in the communication network. As described above, a common channel signaling system for realizing a service to be provided by transmitting and receiving a signal between nodes in a communication network is indispensable.

[0003] The common channel signaling system is the International Telecommunication Union Telecommunication Standardization Sector (International Telecommunications).
Union-Telecommunication Sector: hereinafter abbreviated as ITU-T. ) Is one of the signaling methods recommended in the above. Among them, a signaling system called “No. 7 common channel signaling system” has been introduced as a basis of the ISDN signaling system.

[0004] FIG. 8 is a block diagram of No. 1 recommended by the ITU-T. 7
1 shows an outline of a functional configuration of a common channel signaling system. No. The 7 common channel signaling system is not only applied to the setting of a communication line between exchanges in a conventional telephone service, but also is divided into functional levels 1 to 4 in order to provide a more advanced network service. The technical conditions are defined as specifications at each level.

"Level 1" signal data link section 10
Defines physical and electrical conditions such as the signal speed and transmission system of mutually connected signal lines. The “level 2” signal link function unit 11 defines transmission and reception of messages on the established signal line, and transfer management procedures such as error detection and flow control. The signal data link unit 10 and the signal link function unit 11 enable mutually reliable message transfer, and both are collectively handled as the signal link unit 12.

The "level 3" signal network function unit 13 selects an optimum route for the message transfer performed by the above-described signal link unit 12 based on the state of the signal network, or switches a route when an error occurs. Such procedures are prescribed. The signal link unit 10 and the signal network function unit 13 enable the transfer of a message based on the signal network address.
Message transfer unit (Message Transfer
Part: Hereinafter, abbreviated as MTP. ) 14.

[0007] The signal connection control section (Signalin
g Connection Control Part: Hereinafter abbreviated as SCCP. ) 15 controls the efficient transfer of non-line-compatible signals, such as a query to a switching center and a database for service provision, which do not correspond to actual message transfer, in a form that captures the functions of the MTP 14. That is, subsystems corresponding to each application of the signaling point are managed, while connection-oriented transfer is enabled. Further, the user units 16 _{1 to} 16 _N handle a signal function for providing each service to be applied to the telephone service and the ISDN. Transaction Capabilities (hereinafter abbreviated as TC)
Reference numeral 17 centrally controls data transmission of maintenance operation information and service processing information between stations using the SCCP 15 irrespective of call control. Application Part 18 ₁ ~18 _M
Can use the TC unit 17 to inquire of operation information and service information, transfer a transaction for an application, and provide a service dependent on an individual application.

FIG. 9 shows an outline of a configuration of a signal network based on such a common channel signaling system. The signaling network has a switching center 20 _1, 20 _2, telephone line 21
Connected by Call information transmitted and received between these switching center 20 _1, 20 ₂ is transferred via the communication line 21. The exchanges 20 ₁ and 20 ₂ have control units 22 ₁ and 22 ₂ , respectively, and transmit and receive control signals to and from each exchange by using call information transmitted and received via the communication line 21. Control for providing a predetermined service can be performed. Transmission and reception of control signals between these exchanges are performed via signaling stations 23 ₁ and 23 ₂ connected to the exchanges 20 ₁ and 20 ₂ , respectively, and signal dedicated lines 24 ₁ and 24 ₂ called signal links. It is connected to the common line signal network 25 via the communication line. As described above, in the common channel signaling system, the transmission and reception of signals between the exchanges is characterized in that a signal network is constituted by signal line dedicated lines 24 ₁ and 24 ₂ called signal links different from the communication line 21. Becomes As a result, it is possible to transfer a signal at a high speed and realize an advanced signal function by abundant signal expression.

In a signal network controlled based on mutual control signals and communication information, such as the common channel signal network described above, if one of the exchanges stops functioning during communication, it is restarted. It is necessary to determine in advance the procedure to be performed. For example, if the receiving side stops the function and the procedure for resuming the function is uncertain, if the communication is resumed at the convenience of the exchanges, the transmitting side continues the communication, and the receiving side receives the data when the function is stopped. There is a problem such as inconsistency in transmission / reception signals that discards an expected signal. The control including such a procedure is performed according to No. 1 shown in FIG.
According to the functional configuration of the 7 common channel signaling system, the "level 4" SCCP 15 that manages each subsystem can be used.

Such a procedure is performed, for example, in a specification description language (Specification and Descriptor) recommended by IDU-T.
By controlling the state of a subsystem (Subsystem: hereinafter, abbreviated as SS), which is a functional part of each exchange, as a procedure for restarting communication, the procedure for restarting communication is controlled by ion language (SDL). doing. That is, the exchanges are all exchanges (ground stations) with which they communicate.
The state of the SS as a communication partner is divided into an “permitted” state and a “prohibited” state according to each response, so that transmission / reception is possible in the “permitted” state and “prohibited”. In the state, transmission and reception are disabled. When the communication is resumed, the following two procedures are known according to the initial setting value of the SS state.

First, in the first procedure, the exchange which has resumed communication sets the stored SS states of all ground stations to "permitted".
In this state, unit data (hereinafter, abbreviated as UDT) signals are transmitted to SSs of all ground stations including these SSs. When the SS of the ground station cannot receive the UDT signal, the SS receives the received UDT signal.
Discard signal and disable subsystem
Prohibited: Hereinafter, an SSP) signal is returned. Then, the exchange which has received the SSP signal as the return signal of the UDT signal sets the SS state corresponding to the ground station to the "prohibited" state so that the communication after the restart is not performed.

[0012] The second procedure is that the exchange which has resumed communication sets the SS state of all the ground stations stored to the "prohibited" state and sends a subsystem to all the ground stations including these SSs. Test (Subsystem Status Test: SS
Abbreviated as T. ) Send the signal. The SS of the ground station is this SS
When the T signal is received and communication has been performed with this exchange, a Subsystem Allowed (hereinafter abbreviated as SSA) signal is returned. If communication has not been established with this exchange, SS
Return the P signal. And SS from the ground station
The exchange which has received the SSA signal as a response signal to the T signal sets the SS state corresponding to the ground station to the "permitted" state so as to perform communication after resumption.

[0013] Regarding such a procedure at the time of resuming communication, in the first procedure, when the SS of the ground station cannot receive the UDT signal, the UDT transmitted from the station which resumed communication is transmitted.
There is a problem that the signal is discarded and this discarding continues unless the SSP signal is returned from the ground station and the SS state corresponding to the ground station is set to the “prohibited” state. On the other hand, in the second procedure, first, the SS state is set to the “permissible” state in response to the return signal from the ground station, and then the U
Since the DT signal is transmitted, the UDT signal is not discarded at the ground station, so it can be said that the UDT signal has high reliability. From such a point, the second procedure is often used. Hereinafter, the second procedure will be described.

Next, the operation of the exchange shown in FIG. 9 will be described based on the second procedure. Switching center 20 _1, 20 ₂ shown in FIG. 9, the same for the signaling network control configuration about the common channel signaling network, in the following described with respect to the mobile switching center 20 _1, the description thereof will be omitted about the switching center 20 _2.
The control unit 22 ₁ includes a central processing unit (not shown) (Central Pr
ocessing Unit: Hereinafter, abbreviated as CPU. ) And its CP
Read-only memory (Read On
ly Memory: hereinafter abbreviated as ROM. ) And a memory for storing intermediate results and processing results of the CPU. CPU
Reads the contents of the ROM in a timely manner and performs processing based on the read control procedure. Further, the memory has a SS table storing SS state corresponding to the SS for all ground stations exchange station 20 ₁ communicates.

Note that the No. 1 shown in FIG. According to the functional configuration of the 7 common channel signaling system, SCCP15 of "level 4" corresponds to the control unit 22 _1.

FIG. 10 shows an outline of the structure of such an SS table. This SS table 26
, Corresponding to the SS for all ground stations exchange station 20 ₁ communicates, each SS state 27 _1, 27 ₂ is adapted to store .... Each of the SS states is either an “allowed” state indicating that communication is possible after the communication is resumed as described above, or a “prohibited” state indicating that communication is not possible after the communication is resumed. Is stored.

The control unit 22 ₁ has a memory which stores such a SS table, performs the signal transmission and reception with an exchange 20 _2, predetermined with respect to the common channel signaling network 25 via the signal station 23 ₁ It sends a signal message in a different format.

FIG. 11 shows an outline of the structure of such a signaling message. This signal message 2
8 includes a common unit 29 and an individual unit 30. The common unit 29 further includes identification information of a destination and a transmission source of a message to be transferred, a signaling point code for identifying a base station, and a subsystem number (Subsystem Number: hereinafter, SSN) for identifying a specific user function of the signaling point. Abbreviated) and a label 31 on which the number of the selected signal link is set,
It is composed of a message code 32 indicating the type of a transfer message such as an SST signal, an SSP signal or an SSA signal. Further, the individual unit 30 stores data 3 representing parameters to be set in the specific message and the message itself.
3. Note that the signal station code for identifying the ground station is a destination signal station code (Destination P code).
oint Code: Hereinafter, abbreviated as DPC. ) And an originating point code (OPC).

Therefore, with the configuration of the signaling message as described above, the type of the received signaling message and the transmission source are identified by the DPC and SSN included in the transmission source information with respect to the signaling message received at each exchange. You can do it.

Next, in the exchange having the above-described configuration, the processing when the communication is resumed after the interruption during the communication and the communication resuming operation according to the response from the SS of the ground station by this processing will be described. I do.

[0021] Figure 12 shows the outline of the exchange station 20 ₁ is process when function stop again after the communication resumption of the control unit 22 ₁ resume communication during the communication. Exchange 20
_{When the} function has to be stopped for some reason or when the communication is restarted after the function has been temporarily stopped due to a forced stop due to maintenance or the like (step S35: Y), the SS shown in FIG. The table is referred to (step S36). The SS table, the switching center 20 ₁ stores the respective SS state in response to the SS of all ground station communicating, identifying deposition signaling point code of the ground station (DP
C) and a subsystem number (SSN) for identifying the SS can be searched.

After referring to this SS table, the SS of the ground station
By setting the stored SS state to the “prohibited” state (step S37), communication restart is not permitted. Then, the SS set to this “prohibited” state
, An SST signal is transmitted (step S38). The process of setting the SS state and transmitting the SST signal is repeated until the process is performed for all SSs stored in the SS table (step S39: N). When similar processing is performed on all SSs stored in the SS table (step S
39: Y), a series of processing ends.

[0023] FIG. 13 is an overview of a process procedure for communication resumption processing by the communication resuming operation of the control unit 22 ₁ of the switching center 20 ₁ after the response of the transmitted SST signals to ground station shown in FIG. 12 Is expressed. As a response to the SST signal transmitted to the SSs of all ground stations when communication is resumed in FIG. 12, when the SSs of all ground stations can communicate,
The SSA signal of the format shown in FIG. Therefore, the exchange which transmitted the SST signal at the time of restarting communication waits for the reception of the SSA signal (step S4).
0: N). If the SSA signal is received (step S40: Y), the source DPC and SSN are extracted from the label of the received SSA signal (step S41).
Then, the SS table is referred to from the extracted DPC and SSN (step S42), and the SS state of the SS of the corresponding ground station is set to be “communicable” and set to “permitted” (step S43), and a series of processing ends. I do.

As described above, when the communication is resumed, the S
The S state is set to the “prohibited” state, and the SST signal is transmitted to the SSs of all ground stations that are communication partners. Only the SS of the ground station that has returned the SSA signal in response to the SST signal is allowed to resume communication after interruption, and the SS state is set to the “permissible” state to continue the communication.

In addition, Japanese Patent Application Laid-Open No. 7-203049 discloses a technique of initializing and restarting network processing when a network communication system stops functioning due to a failure. This is because, when replacing a relatively long control signal arriving from the common channel signaling network with a local reference number for a local link, the means for generating the local reference number always assigns a different number as the local reference number before the communication interruption. It was made. In other words, a local reference number assigned to a certain process before interruption and a local reference number newly assigned to another process after resumption do not overlap. Accordingly, it is not necessary to stop the temporary signal processing immediately after resuming to wait for the completion of the processing to which the local reference number is assigned before the interruption, and it is possible to prevent the occurrence of a new trouble due to the stop of the signal processing.

[0026]

The switching center as described above manages the communication permission state of the communication partner and, when the communication is resumed, temporarily prohibits communication to all communication partners.
In addition to setting a state, the communication partner is set to the communication "permissible" state for transmitting a test signal and returning a predetermined response signal of the test signal to resume communication. Therefore, immediately after the communication is resumed, the SS state of the SSs of the ground stations that are all communication partners is set to the “prohibited” state.
Even if the UDT signal is normally received from the ground station immediately after the restart, communication cannot be restarted, and the UDT signal that should have been received normally is discarded.

In particular, all UDT signals are discarded until the SSA signal from the ground station responding to the SST signal is received, and a retry request is generated in the case of normal communication with the exchange. As a result, when communication is performed with a large number of ground stations at the time of communication interruption, all such normal UDT signals are discarded, and retransmission is frequently performed by a retry request, so that traffic significantly increases. There is also a problem. This is SST
This causes a delay in signal transmission, and causes a vicious cycle in which communication restart is delayed more.

Accordingly, an object of the present invention is to provide a network communication system in which communication is resumed as soon as possible without destroying normal communication information from the communication destination when communication is resumed after interruption during communication with the communication destination. Another object is to provide a storage medium for realizing this system.

[0029]

According to the first aspect of the present invention, (a) the communication with the destination communication station is stopped immediately after the communication is resumed after the communication with the destination communication station is interrupted in advance for each of the destination communication stations. (B) when communication is restarted, the restart information stored in the restart information storing means is set to indicate that the restart information has just been restarted. Test signal transmitting means for transmitting a predetermined test signal to all destination communication stations
(C) reply signal receiving means for receiving a predetermined reply signal returned from the destination communication station in response to the test signal transmitted by the test signal transmitting means, and (d) receiving the reply signal by the reply signal receiving means. Communication restart determining means for determining whether or not the restart information stored in the restart information storage means corresponding to the destination communication station which has returned the reply signal based on the reply signal indicates that communication has just been restarted. When,
(E) The network communication system includes communication means for communicating with the destination communication station when it is determined by the communication restart determination means that the restart information of the destination communication station indicates that communication has just resumed. .

That is, according to the first aspect of the present invention, the restart information indicating that the communication is immediately after the communication restart after the interruption is stored in the restart information storage means for each of the communication stations as the transmission destinations. ing. When the communication is resumed after the interruption in advance, the restart information is set to be immediately after the communication is resumed, and a predetermined test signal is transmitted to all the destination communication stations. When a predetermined reply signal is received in response to this test signal, if the restart information stored in the restart information storage means is set to immediately after the start of communication, the communication with the destination communication station that transmitted this reply signal is interrupted. The previous communication is restarted.

According to the second aspect of the present invention, (a) communication permission information indicating whether or not communication with the destination communication station is permitted for each of the destination communication stations and the destination communication Restart information storage means for storing restart information indicating whether or not communication with the station has been immediately resumed after communication has been interrupted; and (b) when restarting communication, the restart information storage means stores the restart information. Communication permission information corresponding to the destination communication station is set to be not permitted, and the restart information is set to be represented as immediately after the communication is restarted, and the communication is restarted to transmit a predetermined test signal to all the destination communication stations. Setting means; (c) reply signal receiving means for receiving predetermined first and second reply signals returned from the destination communication station in response to the test signal transmitted by the communication restart setting means; Based on the first reply signal received by the reply signal receiving means, the resumption information stored in the resumption information storage means corresponding to the destination communication station that has returned the reply signal indicates that the communication has just been resumed. (E) when a predetermined second reply signal is received by the reply signal receiving means, and when the restart information of the destination communication station is transmitted by the restart determining means immediately after the communication is restarted. When it is determined that the communication permission is stored, the communication permission information stored in the restart information storage means corresponding to the transmission destination communication station that transmitted the reply signal is set as the communication permission. And a communication means for communicating with the destination communication station.

That is, according to the second aspect of the present invention, the communication permission information indicating the communication permission after the communication restart and the communication immediately after the communication restart after the interruption in advance correspond to each communication station as the transmission destination. The restart information and the restart information are stored in the restart information storage means. When the communication is resumed after the interruption of the communication in advance, the resumption information is set as immediately after the communication is resumed, the communication permission signal is set as communication non-permission, and a predetermined test signal is transmitted to all the destination communication stations. I am trying to do it. When a predetermined first reply signal is received in response to the test signal, if the restart information in the restart information storage means corresponding to the destination communication station is set to be immediately after the communication is restarted, this reply is returned. The communication before the interruption is resumed with the destination communication station that transmitted the signal. Further, when the first reply signal is received in response to the test signal, the communication before the interruption is resumed with the destination communication station that transmitted the reply signal.

According to the third aspect of the present invention, (a) communication permission information indicating whether or not communication with the destination communication station is permitted corresponding to each of the destination communication stations, and the destination communication Restart information storage means for storing restart information indicating whether or not communication with a station has just been restarted immediately after communication has been interrupted; and (b) a condition for restarting a predetermined communication corresponding to a destination communication station. A restart condition storage means for storing the restart condition information to be transmitted, and (c) when the communication is restarted, the communication permission information corresponding to the destination communication station stored in the restart information storage means is set as communication non-permission. Communication restart setting means for setting each of the communication signals as immediately after communication restart and transmitting a predetermined test signal to all the destination communication stations; and (d) the test signal transmitted by the communication restart setting means. Reply signal receiving means for receiving predetermined first and second reply signals returned from the transmission destination communication station in response thereto, and (e) the first and second reply signals received by the reply signal receiving means. Condition determining means for determining whether or not a communication restart condition based on restart condition information stored in the restart condition storage means corresponding to the destination communication station which has returned these reply signals is satisfied; When the determination means determines that the first reply signal satisfies the corresponding communication restart condition, the restart information storage means corresponding to the destination communication station that transmitted the reply signal based on the first reply signal is stored in the restart information storage means. A restart determining means for determining whether the stored restart information indicates that the communication has just been restarted, and (g) the condition determining means determines that the second reply signal satisfies the corresponding communication restart condition. Corresponding to the destination communication station that transmitted the reply signal when the resumption determination means determines that the resumption information of the destination communication station indicates that communication has just resumed. The communication permission information stored in the restart information storage means is set as communication permission, and the restart information is set so as to indicate that it is not immediately after the communication restart, and the transmission / reception means for transmitting / receiving the communication with the destination communication station. A network communication system is provided.

That is, according to the third aspect of the present invention, the communication permission information indicating the communication permission after the communication restart and the communication immediately after the communication restart after the interruption in advance correspond to each of the communication stations as the transmission destinations. The restart information and the restart information are stored in the restart information storage means. Further, a predetermined communication restart condition is stored in the restart condition storage means corresponding to the destination communication station. When the communication is resumed after the interruption of the communication in advance, the resumption information is set as immediately after the communication is resumed, the communication permission signal is set as communication non-permission, and a predetermined test signal is transmitted to all the destination communication stations. I am trying to do it. When a predetermined first reply signal is received in response to the test signal, it is determined whether or not the communication restart condition stored in the restart condition storage means is satisfied. When the restart information in the restart information storage means corresponding to the station is set to be immediately after the communication is restarted, the communication before the interruption is resumed with the destination communication station that transmitted the reply signal. Further, when the first reply signal is received for the test signal, it is determined whether or not the communication restart condition stored in the restart condition storage means is satisfied, and if so, the reply signal is transmitted. The communication before the interruption is resumed with the destination communication station.

According to the fourth aspect of the present invention, (a) corresponding to each of the communication stations as the transmission destinations, indicates whether or not the communication with the transmission destination communication station has been interrupted in advance and immediately after the communication restart. A resumption information storage means for storing resumption information is provided in a part of the storage area, and (b) when the communication is resumed, the resumption information stored in the resumption information storage means indicates that the communication has just been resumed. (C) transmitting a predetermined test signal to all the destination communication stations, and (c) returning a response from the destination communication station according to the test signal transmitted in the test signal transmission step. A reply signal receiving step of receiving a predetermined reply signal, and (d) replaying the reply signal corresponding to the destination communication station which has returned the reply signal based on the reply signal received in the reply signal receiving step. A communication restart determination step for determining whether or not the restart information stored in the information storage means indicates that the communication has just been restarted; and And a communication step of performing communication with a destination communication station when it is determined that the communication procedure has just been resumed. It is characterized by:

That is, in the fourth aspect of the present invention, each procedure for performing the control operation of the storage means and the network communication system according to the first aspect of the present invention is stored in a storage medium, whereby a network using this storage medium is stored. The communication system can resume communication without destroying normal communication information even when the communication is resumed.

According to the fifth aspect of the present invention, (a) communication permission information indicating whether or not communication with the destination communication station is permitted corresponding to each of the destination communication stations, and the destination communication (B) providing, in a part of the storage area, restart information storage means for storing restart information indicating whether or not the communication with the station has just been resumed immediately after the communication is restarted;
When the communication is restarted, the communication permission information corresponding to the destination communication station stored in the restart information storage means is set to be not permitted for communication, and the restart information is set to be expressed as immediately after the communication is restarted. A communication restart setting step of transmitting a predetermined test signal to the destination communication station;
(C) The first predetermined response returned from the destination communication station in response to the test signal transmitted in the communication restart setting step.
And a reply signal receiving step of receiving a second reply signal; and (d) restart information corresponding to a destination communication station that has returned the reply signal based on the first reply signal received in the reply signal receiving step. A restart determination step for determining whether the restart information stored in the storage means indicates that the communication has just been restarted, and (e) when a predetermined second reply signal is received by the reply signal receiving step When it is determined in the restart determination step that the restart information of the destination communication station indicates that communication has just been restarted, the restart information is stored in the restart information storage means corresponding to the destination communication station that transmitted the reply signal. The communication permission information is set as communication permission, and the restart information is set as not immediately after the communication is restarted. It is characterized in that it is a network communication system control storage medium storing a communication step at least includes control procedures in other parts of the storage area to be.

That is, in the fifth aspect of the present invention, each procedure for performing the control operation of the storage means and the network communication system according to the second aspect of the present invention is stored in a storage medium, whereby a network using this storage medium is stored. The communication system can resume communication without destroying normal communication information even when the communication is resumed.

According to the sixth aspect of the present invention, (a) communication permission information indicating whether or not communication with the destination communication station is permitted corresponding to each of the destination communication stations, and the destination communication Restart information storage means for storing restart information indicating whether or not communication with a station has just been resumed immediately after communication has been interrupted, and restart conditions indicating predetermined communication restart conditions corresponding to the destination communication station (B) when the communication is restarted, the communication permission information corresponding to the destination communication station stored in the restart information storage means is communicated. (C) a communication restart setting step of setting the restart information to be represented as immediately after communication restart as non-permission and transmitting a predetermined test signal to all destination communication stations;
A return signal receiving step of receiving predetermined first and second return signals returned from the destination communication station in response to the test signal transmitted by the communication restart setting step;
(D) Communication based on the restart condition information stored in the restart condition storage means, in which the first and second reply signals received in the reply signal receiving step correspond to the destination communication station that returned these reply signals. A condition determining step of determining whether or not the restart condition is satisfied; and (e) determining that the first reply signal satisfies the corresponding communication restart step by the condition determining step, A restart determination step for determining whether or not the restart information stored in the restart information storage means corresponding to the transmission destination communication station that has transmitted the reply signal indicates that the communication has just been restarted; And (2) when the condition determination step determines that the second reply signal satisfies the corresponding communication restart condition, When it is determined that the open information indicates that the communication has just been resumed, the communication permission information stored in the restart information storage means corresponding to the destination communication station that transmitted the reply signal is used as the communication permission, and And a communication procedure including at least a communication transmitting / receiving step of performing transmission and reception of the communication with the destination communication station and storing the control procedure in another portion of the storage area. It is characterized by being a storage medium for use.

That is, in the present invention, each procedure for controlling the storage means and the network communication system according to the third aspect of the present invention is stored in a storage medium, whereby a network using this storage medium is stored. The communication system can resume communication without destroying normal communication information even when the communication is resumed.

[0041]

BEST MODE FOR CARRYING OUT THE INVENTION

[0042]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to embodiments.

First Embodiment

FIG. 1 shows an outline of a configuration of a network communication system according to a first embodiment of the present invention. This network communication system comprises a first exchange 50 for transmitting and receiving signaling messages and a second exchange 5
1 and a first exchange 50 and a second exchange 5
1 is connected by a signal line 52. However, since each can be identified by DPC, the first
The operation described below is the same in a configuration in which a plurality of second exchanges 51 are connected to the exchange 50.

The first exchange 50 and the second exchange 51 are equipped with SCCPs 53 and 54, respectively. By managing the SS of each exchange, a database (not shown) for providing an exchange service is provided. Controls non-line compatible signals such as inquiries.

In the following, the first exchange 50 and the second exchange 51 will be described in order to facilitate understanding of the operation in this embodiment.
It is assumed that the configuration regarding the communication restart processing according to the present embodiment is the same. Further, the first exchange 50 and the second exchange 51 assume that the communication function of the first exchange 50 has been temporarily stopped for some reason during the communication, and the direction of the transmission / reception of the communication interrupted during the communication is as follows. Irrelevant. As described above, the first exchange 50 and the second exchange 51 are different only in the transmitting side and the receiving side of the signal communicated via the communication line 52. 1 exchange 50
Will be described, and description of the second exchange 51 will be omitted.

Next, the SCCP 53 which is a main component of the first switching center 50 of the network communication system shown in FIG.
Will be described.

FIG. 2 shows an outline of the configuration of the SCCP 53 which is a main component of the first exchange 50 shown in FIG. The SCCP 53 includes a control unit 55 that performs processing for transmitting / receiving a signaling message and restarting communication, a memory unit 56 for storing SS management information of the ground station, and an interface unit 5 for transmitting / receiving a communication message to / from the ground station.
7 is provided. The control unit 55 includes a CPU 58 and a ROM
The CPU 58 performs communication restart processing by sequentially reading out the communication restart processing procedure from the ROM 59 in which the procedure is stored. The interface unit 57 includes a signal assembling unit 60 and a signal transmitting / receiving unit 61.
The signal assembling unit 60 assembles and extracts the signal format shown in FIG. 11 for a signal to be transmitted and received as a signal message according to an instruction from the control unit 55, and the signal transmitting and receiving unit 61 is configured by the signal assembling unit 60. The transmission of the transmitted signal message and the reception of the signal message from the ground station are performed to the signal assembling section 60.

The memory unit 56 is used as a temporary work memory for processing results during processing based on the processing procedure stored in the ROM 59 as needed, and stores the SS management information of the ground station as described above. . The SS management information stored in the memory unit 56 is stored for each SS of the ground station.
Not only the status but also the restart flag is stored.

FIG. 3 shows an outline of the configuration of the SS management table for storing the SS management information of the ground station stored in the memory unit 56 shown in FIG. The SS management table 62 includes SS management information 63 for each SS of the ground station.
_1, 63 _2, has a ... and each restart flag 64
_1, 64 _2, ..., SS state 65 _1, 65 _2, and a ... and. Each of the restart flags 64 ₁ , 64 ₂ ,... Can store one of two values: an “on” state indicating that communication has been restarted, and an “off” state indicating that communication has not been restarted. The SS states 65 ₁ , 65 ₂ ,.
The state is divided into an “permitted” state and a “prohibited” state, and when the state is “permitted”, the state can be stored as a communicable state.
SS management information 63 ₁ , 6 corresponding to these ground station SSs
3 _2, ... it is adapted to be able to search by DPC and SSN identifying a ground station with respect to SS management table 62.

Next, the SS management information 6 corresponding to the SS of the ground station stored in such an SS management table.
The procedure of the process performed by the SCCP 53 at the time of resuming communication and the procedure of the communication resuming operation after responding by this process will be described using 3 ₁ , 63 ₂ ,.

FIG. 4 shows an outline of a processing procedure at the time of restarting communication of the SCCP 53 in which the first switching center 50 has stopped functioning during communication and restarted communication. When the function of the first exchange 50 has to be stopped for some reason or after the function is temporarily stopped by a forced stop due to maintenance or the like, the SCCP 53 detects whether or not the communication is restarted (step). S70). When the SCCP 53 restarts the communication (step S70: Y), the SCCP 53 refers to the SS management table shown in FIG. 3 (step S71), and when the restart of the communication cannot be detected, the detection is further continued (step S70: N). In the SS management table stored in the memory unit 56, respective restart flags 6 corresponding to the SSs of all ground stations with which the first exchange 50 communicates are stored.
4 _1, 64 _2,... And SS state 65 _1, 65 _2, stores and .... After referring to this SS management table, the S
The restart flag stored for each S is turned on,
S state is set to “prohibited” state (step S
72, S73). Then, an SST signal is transmitted to the SS whose SS state is set to the “prohibited” state (step S74). The setting of the restart flag and the SS state and S
The transmission process of the ST signal is similarly performed for all SSs stored in the SS management table (step S75:
N). Such setting is completed for all SSs stored in the SS management table (step S75: Y).
Then, a series of processing ends.

The SCCP 53 of the first switching center 50 can perform an optimum communication restart operation in response to a response signal to the SST signal transmitted as such a process at the time of restarting communication.

FIG. 5 shows the SCCP 53 of the first exchange 50.
Shows an outline of a procedure of a communication restarting operation performed in response to a response signal to the SST signal transmitted at the time of restarting communication. First, the SCCP 53 of the first switching center 50 that has transmitted the SST signal at the time of restarting communication waits for reception of a response signal from the SS of the ground station to which the SST signal is to be transmitted (step S76). Then, when the SSA signal is received as the response signal (step S76: Y), the reception SSA having the format configuration of the signal message shown in FIG.
DP of the ground station of the first switching center 50 that is the transmission source from the signal
C and its SSN are extracted (step S77). Then, the SS management table is referred to based on the extracted DPC and SSN (step S78), and the SS state of the SS of the corresponding DPC is set as an “permitted” state, and the restart flag is set as an “off” state. Step S7
9, S80). As a result, communication with the SS of the base station that has transmitted the SSA signal in response to the SST signal transmitted by the first switching center 50 when the communication is resumed can be continued even after the communication is resumed.

When the signal message received in step S76 is not an SSA signal (step S76:
In N), it is further determined whether the signal is a UDT signal or an SST signal (step S81). If the received signal message is neither the UDT signal nor the SST signal (step S81: N), it is determined that the received signal message is not a valid signal message for resuming communication, and the reception of the previous SSA signal is waited again. Become. When the received signal message is a UDT signal or an SST signal (step S81: Y), the first switching center 50 serving as a transmission source from the received signal message having the format configuration of the signal message shown in FIG. Ground station DPC
And SSN are extracted (step S82). Then, the SS management table is referred to based on the extracted DPC and SSN (step S83).

Then, it is determined whether or not the resume flag of the SS of the corresponding DPC is in the “on” state (step S).
84). When the restart flag is in the "OFF" state (step S84: N), the second switching center 51 immediately after the communication is restarted.
, Indicates that a normal UDT signal or SST signal has not been transmitted. Therefore, there is no need to perform communication restart continuation processing, and the series of processing ends.
When the restart flag is in the “ON” state (step S84: Y), the second exchange 51 does not recognize that the first exchange 50 has temporarily stopped the communication function immediately after the communication is resumed. Since the normal UDT signal or the SST signal has been transmitted to the base station, the received UDT signal or the SST signal stored in the SS management table is transmitted to the ground station in order to perform the communication resumption continuation process. DP
The SS state of the SS of C is set as the “permitted” state, and the restart flag is set as the “off” state (step S7).
9, S80), and a series of processing ends.

As described above, in the network communication system according to the first embodiment, each switching center has an SS state indicating a communication permission state corresponding to the SSs of all ground stations and a state immediately after communication restart. An SS management table storing the indicated restart flag is provided. Then, after the communication is resumed after the communication is temporarily interrupted, the SS resume flags of all ground stations are set as immediately after the communication is resumed, and the SST
The signal was sent. Thereby, the conventional SST
Not only the SSA signal which is a predetermined response signal of the signal,
Since the own station can identify the SS of the ground station which has transmitted a normal UDT signal or SST signal as usual without recognizing that the communication function has been stopped, it can recognize that it is immediately after the communication is restarted. SS state is “allowed”
By setting the status, communication can be resumed immediately.
Therefore, the overhead at the time of restarting communication as a network communication system can be significantly reduced, and an increase in traffic at the time of restarting communication can be avoided.

Second Embodiment

In the network communication system according to the first embodiment described so far, the SS state corresponding to the SS of the ground station with which the exchange station communicates corresponds to the SS state indicating permission or non-permission of communication, respectively, and immediately after the restart of communication. The resumption flag indicating whether or not is stored in the SS management table. However, when communication is resumed, noise may be recognized as a received signal depending on the electrical conditions and length of the communication line, which is a period during which it is difficult to maintain communication quality reliability.

Therefore, the switching center of the network communication system according to the second embodiment transmits the S
A restart condition table for storing a response signal to the ST signal and the number of times the signal should be received corresponding to the SS of all ground stations is provided. As a result, the SCCP performs communication restart processing based on the storage information in the SS management table shown in FIG. 3 and the restart condition in the restart condition table. More specifically, the response signal returned in response to the SST signal is received a predetermined number of times by the predetermined response signal stored in the restart condition table, and then the communication restart similar to that of the first embodiment is performed. Processing will be performed.

The network communication system according to the second embodiment has the same configuration as the network communication system according to the first embodiment shown in FIG. 1, and illustration and description thereof are omitted. Further, since the same applies to the main components of the network communication system, for example, S
Description of the CCP and SS management tables will be omitted. Therefore, the first exchange 5 will be described below in the same manner as in the first embodiment.
0 will be described.

SCCP in First and Second Embodiments
The difference of 53 is that the memory unit 56 or the ROM 59
Condition table stored in ROM and accompanying ROM 59
In the communication restart operation procedure stored in.

FIG. 6 shows an outline of the configuration of the restart condition table stored in the memory unit 56 or the ROM 59 of the SCCP 53 of the first exchange 50 in the second embodiment. The restart condition table 90 has the same information as the SS management table shown in FIG.
Each S has resumption condition information 91 ₁ , 91 ₂ ,.... The restart condition information 91 ₁ , 91 ₂ ,...
The response signals 92 ₁ , 92 ₂ ,... To the SST signal transmitted at the time of communication restart for each S, and the number of times 93 ₁ ,
93 ₂ ,... Therefore, in order to continue the communication operation with the ground station when the communication is restarted, it is necessary to satisfy the restart condition stored in the restart condition information. This makes it possible to improve the response reliability of the SST signal when resuming communication.

Next, the restart conditions 91 ₁ , 9 corresponding to the SS of the ground station stored in such a restart condition table.
The procedure of the communication restarting operation performed by the SCCP 53 in response to the response from the ground station when the communication is restarted will be described using 1 ₂ ,. When the communication is resumed as shown in FIG.
Since the setting of the SS management information of the SS management table and the transmission of the SST signal performed in correspondence with the SSs of all the ground stations are the same, the description will be omitted.

FIG. 7 shows an outline of a procedure of a communication restart operation performed in response to a response signal to the SST signal transmitted by the SCCP 53 of the first exchange 50 in the second embodiment when the communication is restarted. . First, when communication is resumed, S
SCCP 53 of first switching center 50 that has transmitted the ST signal
Waits for a response signal from the SS of the ground station to which the SST signal is to be transmitted (step S95). When an SSA signal is received as a response signal (step S95:
In Y), the DPC and the SSN of the ground station of the first exchange 50 serving as the transmission source are extracted from the received SSA signal having the format configuration of the signal message shown in FIG. 11 (step S96). Then, based on the extracted DPC and SSN, the resumption condition table shown in FIG. 6 is referred to (step S97), and it is determined whether or not the resumption condition including the response signal and the number of times to receive the response signal is satisfied (S97). Step S98).

For example, the SSA signal is not registered in the restart condition corresponding to the DPC and SSN, or the SSA signal is not registered.
If the number of signals to be received is not satisfied even if the signal is registered (step S98: N), the reception of the response signal of the SST signal is waited again. However, when the SSA signal is registered in the restart condition and it is determined that the number of times to receive the SSA signal has been exceeded (step S98: Y),
With reference to the SS management table (step S99), the SS state of the corresponding DPC SS is set as an “allowed” state, and the restart flag is set as an “off” state (steps S100 and S101). As a result, the SS in response to the SST signal transmitted by the first exchange 50 when communication is resumed.
The communication with the SS of the base station that transmitted the A signal can be continued as it is even after the communication is resumed.

When the signal message received in step S95 is not an SSA signal (step S95:
In N), it is further determined whether the signal is a UDT signal or an SST signal (step S102). If the received signaling message is neither the UDT signal nor the SST signal (step S102: N), it is determined that the received signaling message is not a valid signaling message for resuming communication, and the reception of the previous SSA signal is waited again. Become. When the received signal message is a UDT signal or an SST signal (step S102: Y), the first switching center 50 serving as a transmission source from the received signal message having the format configuration of the signal message shown in FIG. The DPC and SSN of the ground station are extracted (step S103). Then, based on the extracted DPC and SSN, reference is made to the restart condition table shown in FIG. 6 (step S104), and it is determined whether or not the restart condition including the response signal and the number of times to receive it is satisfied (step S104). Step S105).

For example, when the UDT signal or the SST signal is not registered in the restart condition corresponding to the DPC and the SSN, or when the UDT signal or the SST signal is registered but the number of times to receive the signal is not satisfied (step In S105: N), the reception of the response signal of the SST signal is waited again. However, when the UDT signal or the SST signal is registered in the restart condition and it is determined that the number of times of reception is exceeded (step S105: Y), the SS management table is referred to (step S10).
6).

Then, it is determined whether or not the restart flag of the SS of the corresponding DPC is in the “on” state (step S).
107). When the restart flag is in the "OFF" state (step S107: N), it indicates that a normal UDT signal or SST signal was not transmitted from the second exchange 51 immediately after the communication restart. Thus, the series of processing is terminated without performing the communication restart continuation processing. When the restart flag is in the “ON” state (step S107: Y), the second exchange 51 does not recognize that the first exchange 50 has temporarily stopped the communication function immediately after the communication is resumed. Since the normal UDT signal or the SST signal has been transmitted to the base station, the received UDT signal or the SST signal stored in the SS management table is transmitted to the ground station in order to perform the communication resumption continuation process. The SS state of the DPC SS is set to the “permissible” state, and the restart flag is set to the “off” state (steps S100 and S101), and the series of processing ends.

As described above, in the network communication system according to the second embodiment, each switching center has an SS state indicating a communication permission state corresponding to the SSs of all ground stations and a state immediately after communication restart. An SS management table storing the indicated restart flag is provided. Further, a restart condition table is provided for storing a response signal to the SST signal transmitted at the start of communication and the number of times it should be received, corresponding to the SSs of all ground stations. Then, after the communication is temporarily interrupted, after the communication is restarted, the SS restart flags of all the ground stations are set as immediately after the communication restart, and the SST signal is transmitted. As a result, not only the SSA signal, which is a predetermined response signal of the conventional SST signal, but also a normal UD signal without recognizing that the communication function has been stopped.
SS of the ground station that transmitted the T signal or SST signal
On the other hand, since the own station can identify that it is immediately after the communication is resumed, the SS state of the SS management table is set to the “permissible” state, and the communication can be resumed immediately. Further, since the communication restart processing is performed after receiving the predetermined response signal stored in the restart condition table a predetermined number of times, the overhead at the time of restarting the communication as the network communication system is reduced, and the communication quality is reduced. Can be maintained even immediately after resuming communication, which is difficult to maintain.

[0071]

As described above, according to the first aspect of the present invention, the restart information indicating that the communication has just been resumed immediately after the interruption has been previously resumed, corresponding to each of the communication stations as the transmission destinations. The information is stored in the information storage means. Thus, by receiving a reply signal corresponding to the predetermined test signal transmitted immediately after the restart of communication, communication can be restarted regardless of the conventional communication permission state of each subsystem. Therefore, the overhead at the time of restarting communication as a network communication system can be significantly reduced, and unnecessary increase of traffic at the time of restarting communication can be avoided.

According to the second aspect of the present invention, since the communication permission information is also stored for each subsystem of the ground station, the effect of the first aspect of the invention can be obtained. By using a predetermined response signal of the conventional test signal as the second return signal, there is an effect that compatibility with the conventional test signal can be maintained.

According to the third aspect of the present invention, in addition to storing the communication permission information and the restart information for each subsystem of the ground station, a predetermined communication restart condition is stored in the restart condition storage means. I made it. Thus, when a reply signal to the predetermined test signal transmitted immediately after the communication is restarted is received, the communication can be restarted by referring to the restart flag unless the restart condition stored in the restart condition storage means is satisfied. Since it is not possible to avoid erroneous recognition of communication restart due to unpredictable noise during an unstable period at the time of communication restart, reliability can be maintained even if communication restart processing can be started earlier than before. .

Further, according to the present invention, the predetermined storage means and control procedure for avoiding discarding normal communication information at the time of restarting communication in the network communication system as described above are provided. Since the data is stored in the storage medium, the maintainability and flexibility of the system are improved, and the optimum processing of each network communication system can be easily realized.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an outline of a configuration of a network communication system in first and second embodiments of the present invention.

FIG. 2 shows S in the first and second embodiments of the present invention.
FIG. 2 is a block diagram illustrating a main part of a configuration of the CCP.

FIG. 3 is a table configuration diagram showing an outline of a configuration of a subsystem management table in the first embodiment of the present invention.

FIG. 4 is a flowchart showing an outline of a processing procedure at the time of restarting communication in the first and second embodiments of the present invention.

FIG. 5 is a flowchart showing an outline of a procedure of a communication restart operation in the first embodiment of the present invention.

FIG. 6 is a table configuration diagram showing an outline of a configuration of a restart condition table according to a second embodiment of the present invention.

FIG. 7 is a flowchart showing an outline of a procedure of a communication restarting operation in a second embodiment of the present invention.

FIG. 8 is a diagram showing No. 1 recommended by ITU-T. It is explanatory drawing showing the outline | summary of the functional structure of a 7 common line signal system.

FIG. 9 is a schematic diagram showing an outline of a configuration of a signal network based on a conventional common channel signaling method.

FIG. 10 is a table configuration diagram showing an outline of a configuration of a conventional subsystem table.

FIG. 11 is an explanatory diagram showing an outline of a conventional signal message format configuration.

FIG. 12 is a flowchart showing an outline of a processing procedure at the time of resuming communication in a conventional network communication system.

FIG. 13 is a flowchart showing an outline of a procedure of a communication restart operation in a conventional network communication system.

[Description of Signs] 50 First switching station 51 Second switching station 52 Signal lines 53, 54 Signal connection control unit (SCCP) 55 Control unit 56 Memory unit 57 Interface unit 58 CPU 59 ROM 60 Signal assembly unit 61 Signal transmission / reception Department

Claims (6)

[Claims] 1. Restart information storage means for storing restart information corresponding to each of communication stations serving as transmission destinations, indicating whether or not communication with the transmission destination communication station has just been resumed after communication has been interrupted in advance. A test for setting the restart information stored in the restart information storage means to indicate immediately after restarting communication and transmitting a predetermined test signal to all destination communication stations when communication is restarted. A signal transmitting unit, a return signal receiving unit that receives a predetermined return signal returned from a destination communication station in response to the test signal transmitted by the test signal transmitting unit, and a response signal received by the return signal receiving unit. Whether or not the restart information stored in the restart information storage means corresponding to the destination communication station that has returned the reply signal based on the reply signal indicates that communication has just been restarted. Communication restart determining means for determining; and communication means for communicating with the destination communication station when the communication restart determining means determines that the restart information of the destination communication station indicates that communication has just resumed. A network communication system, comprising: 2. Communication permission information indicating whether or not communication with a destination communication station is permitted for each communication station as a destination, and communication with the destination communication station has been interrupted in advance. Resumption information storage means for storing resumption information indicating whether or not communication has just been resumed, and communication permission information corresponding to the destination communication station stored in the resumption information storage means when communication is resumed Communication rejection setting, communication resumption setting means for setting resumption information as immediately after resumption of communication, and transmitting a predetermined test signal to all transmission destination communication stations. Return signal receiving means for receiving predetermined first and second return signals returned from the destination communication station in response to the test signal thus received; And determining whether or not the restart information stored in the restart information storage means corresponding to the destination communication station that has returned the reply signal indicates that the communication has just been restarted based on the first reply signal. Means that when the predetermined second reply signal is received by the reply signal receiving means, and that the restart information of the destination communication station is immediately after communication restart by the restart determining means. When it is determined that the communication is permitted, the communication permission information stored in the restart information storage unit corresponding to the transmission destination communication station that transmitted the reply signal is represented as communication permission, and the restart information is represented as not immediately after communication restart. And a communication means for communicating with the destination communication station. 3. Communication permission information indicating whether or not communication with the destination communication station is permitted for each of the communication stations to be transmitted, and communication with the destination communication station being interrupted in advance. Restart information storage means for storing restart information indicating whether or not the communication has just been restarted later; restart condition storage means for storing restart condition information indicating predetermined communication restart conditions corresponding to the destination communication station When the communication is restarted, the communication permission information corresponding to the destination communication station stored in the restart information storage means is set to be not permitted to communicate, and the restart information is set to be represented as immediately after the communication is restarted. Communication resumption setting means for transmitting a predetermined test signal to all transmission destination communication stations, and a reply from the transmission destination communication station in response to the test signal transmitted by the communication resumption setting means. Reply signal receiving means for receiving predetermined first and second reply signals; and the first and second reply signals received by the reply signal receiving means correspond to a destination communication station which has returned these reply signals. Condition determining means for determining whether or not a communication restart condition based on restart condition information stored in the restart condition storage means is satisfied; and the communication corresponding to the first reply signal by the condition determining means. When it is determined that the restart condition is satisfied, the restart information stored in the restart information storage means corresponding to the destination communication station that has transmitted the reply signal is based on the first reply signal immediately after the communication restart. And a condition determining unit that determines that the second return signal satisfies the corresponding communication restart condition. And when it is determined by the restart determining means that the restart information of the destination communication station indicates that communication has just been restarted, the restart is performed in response to the destination communication station that transmitted the reply signal. Communication permission means for setting communication permission information stored in the information storage means as communication permission, and setting resumption information as not immediately after communication restart, and for transmitting and receiving communication with the destination communication station. A network communication system, comprising: 4. A resumption information storage means for storing resumption information corresponding to each communication station as a transmission destination, the resumption information indicating whether or not communication with the transmission destination communication station has just been resumed after the interruption beforehand. Is provided in a part of the storage area, and when the communication is restarted, the restart information stored in the restart information storage means is set to indicate that the communication has just been restarted. A test signal transmitting step of transmitting a predetermined test signal; a return signal receiving step of receiving a predetermined return signal returned from a destination communication station in response to the test signal transmitted by the test signal transmitting step; Resume information stored in the resume information storage means corresponding to the destination communication station that has returned the reply signal based on the reply signal received in the reply signal receiving step. A communication resumption judging step of judging whether it represents that it is immediately after the communication resumption,
A communication step of performing communication with the destination communication station when it is determined by the communication restart determination step that the restart information of the destination communication station indicates that communication has just resumed. A storage medium for controlling a network communication system, which is stored in another part of a storage area. 5. Communication permission information indicating whether communication with the destination communication station is permitted for each of the communication stations serving as the destination, and communication with the destination communication station being interrupted in advance. A resumption information storage means for storing resumption information indicating whether or not the communication has just been resumed later is provided in a part of the storage area, and the transmission destination stored in the resumption information storage means when the communication is resumed. A communication restart setting step of setting the communication permission information corresponding to the communication station as communication non-permission, setting the restart information to represent each immediately after the communication restart, and transmitting a predetermined test signal to all the destination communication stations; A reply signal receiving step of receiving predetermined first and second reply signals returned from the destination communication station in response to the test signal transmitted in the communication restart setting step. The restart information stored in the restart information storage means corresponding to the destination communication station that has returned the reply signal based on the first reply signal received in the reply signal receiving step is immediately after the communication restart. A restart determination step for determining whether or not the communication destination station is present, and when the predetermined second return signal is received by the return signal receiving step, the restart information of the destination communication station is determined by the restart determination step. When it is determined that this indicates that communication has just been resumed, the communication permission information stored in the restart information storage means corresponding to the destination communication station that transmitted the reply signal is set as communication permission, and the communication is restarted. And setting a communication step for communicating with the destination communication station at least, A storage medium for controlling a network communication system, wherein the control procedure provided is stored in another part of the storage area. 6. Communication permission information indicating whether communication with the destination communication station is permitted for each of the communication stations to be transmitted, and communication with the destination communication station being interrupted in advance. Restart information storage means for storing restart information indicating whether or not the communication has just been restarted later; restart condition storage means for storing restart condition information indicating predetermined communication restart conditions corresponding to the destination communication station Is provided in a part of the storage area, and when the communication is restarted, the communication permission information corresponding to the destination communication station stored in the restart information storage unit is set to the communication non-permission, and the restart information is transmitted immediately after the communication is restarted. , And a communication restart setting step of transmitting a predetermined test signal to all destination communication stations, and the test transmitted by the communication restart setting step. A reply signal receiving step of receiving predetermined first and second reply signals returned from the transmission destination communication station in response to the signal; and the first and second reply signals received by the reply signal receiving step. A condition determining step of determining whether or not a communication restart condition based on restart condition information stored in the restart condition storage means is satisfied in response to a destination communication station that has returned these return signals; and When it is determined that the first reply signal satisfies the corresponding communication restart step, the restart information storage corresponding to the destination communication station that transmitted this reply signal based on the first reply signal A restart determining step of determining whether or not the restart information stored in the means indicates that the communication has just been restarted; and When it is determined that the second reply signal satisfies the corresponding communication restart condition, and when the restart determination step determines that the restart information of the destination communication station indicates that communication has just been restarted. If so, the communication permission information stored in the restart information storage means corresponding to the destination communication station that transmitted the reply signal is set as communication permission, and the restart information is set as not immediately after communication restart. A storage medium for controlling a network communication system, wherein a control procedure including at least a communication transmitting / receiving step of transmitting / receiving a communication with the destination communication station is stored in another part of the storage area.