JP2994068B2 - Communication availability determination method in communication between heterogeneous packet switches - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for judging the availability of communication in a packet switching network constituted by connecting a plurality of packet switches including heterogeneous packet switches by lines.

When a relatively small-scale packet switching network composed of a plurality of packet switches and other similar packet switching networks are connected to form a relatively large-scale packet switching network, each relatively large-scale packet switching network is constructed. A small-scale packet switching network cannot always realize the same communication service (communication function), and depends on the type of communication service that can be realized by the packet switching network included in the connection path from the originating data terminal to the receiving data terminal. In some cases, the communication request by the outgoing data terminal cannot be permitted.

[0003] The relatively small-scale packet switching network described above is also constituted by a plurality of packet switches, and these packet switches cannot always realize the same communication service. Depending on the type of communication service that can be realized by the packet switch included in the connection path from the data terminal to the incoming data terminal, the communication request by the outgoing data terminal may not be allowed.

For this reason, generally, in a packet exchange accommodating a calling data terminal, it is determined whether or not to permit communication based on information stored in a storage device attached to the packet exchange. doing. As the size of the packet switching network increases, the number of packet switches constituting the packet switching network has become enormous. Therefore, the amount of information stored in the storage device to be used for the above determination becomes enormous, which puts a strain on the storage device and limits the original switching processing performance of the packet switch. Need to improve.

[0005] In the specification of the present application, the term "communication service" refers to a CCI such as an incoming charge, a first select, and the like.
TT (International Telegraph and Telephone Advisory Committee) X. 25, various basic services / optional services permitted for the accommodated data terminal specified in X.25, 75 means various optional services.

[0006]

2. Description of the Related Art A conventional communication availability determination method is shown in FIGS.
This will be described with reference to FIG.

[0007] A general packet switch comprises a central processing unit, a storage device, and a line control device, and various programs and necessary data are stored in the storage device. The data used for the call connection process and for determining whether or not to permit a communication request from the calling data terminal include a station control information table and a communication service provision information definition table between packet switches.

As shown in FIG. 7, the station control information table stores information necessary for call connection, such as routing information, corresponding to station numbers which are identification information of all packet switches constituting the packet switching network. It is a set table.

As shown in FIG. 8, the communication service provision information definition table between packet switches includes communication service information on communication services that can be realized when communication is performed between one packet switch and another packet switch. Is a table set for all combinations of two packet switches.

[0010] Then, when a communication request is issued from the originating data terminal, it is determined whether or not the communication request is permitted by performing processing as shown in FIG.

That is, identification information about the packet exchange accommodating the incoming data terminal included in the communication request from the originating data terminal is obtained (step "abbreviated to ST" 1), and the own packet exchange, ie, the originating data The identification information about the packet exchange accommodating the terminal is obtained (ST2). Next, based on both packet exchange identification information, the communication service provision information definition table between the packet exchanges is searched for a communication service that can be provided (ST).
3) It is determined whether or not the communication service requested by the calling data terminal is included in these available communication services (ST4), and if so, communication is permitted;
That is, call connection processing is performed based on the corresponding routing information in the station control information table (ST5). If not included in ST4, the transmission data terminal is notified of the fact and disconnection processing is performed (ST6).

[0012]

As described above, conventionally, it is necessary to hold communication service information that can be provided with respect to all other packet switches constituting a packet switching network including its own packet switch. Not only
It is also necessary to store and maintain communication service information that can be provided with respect to packet switches constituting all the other packet switching networks capable of intercommunication, so that the number of subscribers and the number of constituent packet switches increase. Accordingly, storage devices (main storage device, external storage device) attached to each packet switch.
However, there is a problem in that the original switching processing performance of the packet switch is limited, such as limiting the number of accommodated data terminals and the amount of traffic.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to be used for judging whether communication is possible or not in a packet switching network constituted by a plurality of different types of packet switches. An object of the present invention is to make it possible to reduce the amount of data to be processed and use the storage area effectively and efficiently to improve the original switching processing performance of the packet switch.

[0014]

A description will be given with reference to the principle explanatory diagram of the present invention shown in FIG.

[0015] In a packet switching network constituted by connecting a plurality of packet switches including heterogeneous packet switches different in at least a part of the communication service functions that can be provided by lines, the plurality of packet switches are connected at the same level. Classification is made for each type of packet switch having a communication service function, and each is defined as a subnetwork. And
A station control information table 1 in which information for identifying a corresponding subnetwork is set corresponding to each of all the packet switches, a packet switch classified into one subnetwork, and a packet switch classified into another subnetwork. Communication service function information on communication service functions that can be provided when it is assumed that communication is performed between packet switches,
The communication service provision information definition table 2 set for all combinations of the two sub-networks is stored and held in the storage device of each packet switch. Further, at the time of a communication request from the outgoing data terminal, the packet switch accommodating the outgoing data terminal extracts identification information of a subnetwork involved in communication from the station control information table 1 (ST1), and Based on the identification information, the available communication service function information is extracted from the communication service machine provision information definition table 2 (ST2), and the communication request from the outgoing data terminal is converted to the extracted available communication service function information. In the light of this, it is configured to determine whether or not it is permissible (ST3).

[0016]

According to the present invention, communication service function information (communication service provision availability information) is not stored and held for each packet switch constituting a packet switching network, and communication is performed for each aggregate called a subnetwork. It stores and retains service function information, and the amount of information can be reduced as the number of types of packet switches decreases. Therefore, the storage area in the storage device attached to the packet switch can be used efficiently, and the performance of the packet switch itself can be improved, such as an increase in the number of subscribers accommodated in the packet switch.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is a block diagram showing the configuration of the packet switch in the embodiment of the present invention. This packet switch includes a central processing unit 11, a main storage device 12, and a plurality of line controllers 13. A data terminal or another packet switch is connected to the line controller 13 via a line 14. ing. The main storage device 12 stores and holds various control information and various control programs necessary for realizing the packet switching process.
Executes a corresponding control program while referring to or updating the control information, thereby starting up the corresponding line control device 14 and performing packet exchange with a data terminal or another packet switch. Is done.

By connecting a plurality of packet switches having such a configuration via a line, a packet switching network as shown in FIG. 3 is formed. In this embodiment, as shown in the figure, all the packet switches constituting this packet switching network are classified into the same type of packet switches having the same level of communication service function, and each is defined as a subnetwork. Then, subnetwork identification information (-1 to -3) is given to each subnetwork.

The main storage device 12 of the packet switch stores and holds a station control information table and an inter-subnetwork communication service provision information definition table. As shown in FIG. 4, the station control information table corresponds to station numbers which are identification information of all the packet switches constituting the packet switching network, information necessary for call connection processing such as routing information, and FIG. Is a table in which the subnetwork identification information defined as above is set.

The inter-subnetwork communication service provision information definition table is, as shown in FIG. 5, a case where communication is performed between a packet switch classified into one subnetwork and a packet switch classified into another subnetwork. FIG. 7 is a table in which communication service function information on communication service functions that can be realized is set for all combinations of two sub-networks.

Next, a description will be given, with reference to a flowchart shown in FIG. 6, of a communication availability determination process in the case of performing communication between different types of packet exchanges.

Upon receiving the communication request from the outgoing data terminal, the packet switch accommodating the outgoing data terminal receives the station number, which is the identification information of the packet switch accommodating the incoming data terminal contained in the communication request. Is extracted, and the subnetwork identification information corresponding to the station number identification information is obtained by referring to the station control information table based on the station number (ST1). Next, based on the station number identification information of the own packet switch, that is, the packet switch accommodating the calling data terminal, similarly, the station control information table is referred to, and subnetwork identification information corresponding to the station number identification information is obtained. (ST2).

Then, based on the subnetwork identification information of the packet exchange accommodating the incoming data terminal extracted in ST1 and the subnetwork identification information of the packet exchange accommodating the outgoing data terminal extracted in ST2, The communication service provision information definition table between sub-networks is searched, and the available communication service function information corresponding to these is extracted (ST3). Next, it is determined whether or not the available communication service function information extracted in ST3 includes the communication service function requested by the calling data terminal (S3).
T4) If included, call connection processing is performed based on the corresponding routing information set in the station control information table (ST5). If it is not included in ST4, the transmission data terminal is notified that communication is not possible, and the line is disconnected (ST6).

The size of the inter-subnetwork communication service provision information definition table is proportional to the number of sub-networks constituting the packet switching network. The smaller the number of types of packet switches, the fewer the combinations are. The storage area required for storing and holding the communication service provision information definition table is reduced, and FIG.
The storage area can be significantly reduced as compared with the conventional communication service providing information definition table between packet switches shown in FIG.

In this embodiment, the main storage device 1
2 stores and retains various information such as a station control information table and an inter-subnetwork communication service provision information definition table. However, in the case where these are stored and retained in an external storage device such as a magnetic disk device. Does not hinder the effects of the present invention.

[0027]

As described in detail above, the present invention classifies a plurality of packet switches constituting a packet switching network into the same type of packet switches having the same level of communication service function, and forms each of them as a subnetwork. Since information about the feasible communication service function set for each combination of sub-networks is stored and held,
Compared with the conventional setting for each combination of packet switches, the amount of information can be significantly reduced, and the inherent performance of each packet switch is improved, such as an increase in the number of subscribers accommodated. This has the effect that it becomes possible.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 2 is a block diagram showing a configuration of a packet switch in the embodiment of the present invention.

FIG. 3 is a diagram showing an example of defining a subnetwork of a packet switching network in an embodiment of the present invention.

FIG. 4 is a diagram showing a station control information table in the embodiment of the present invention.

FIG. 5 is a diagram showing an inter-subnetwork communication service provision information definition table in the embodiment of the present invention.

FIG. 6 is a flowchart of communication availability determination processing in the embodiment of the present invention.

FIG. 7 is a diagram showing a station control information table in the related art.

FIG. 8 is a diagram showing a communication service provision information definition table between packet switches in the related art.

FIG. 9 is a flowchart of a communication availability determination process according to the related art.

[Explanation of symbols]

 1 station control information table 2 communication service provision information definition table

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H04L 12/56 H04L 12/28

Claims (1)

(57) [Claims] 1. In a packet switching network in which a plurality of packet switches including different types of packet switches different in at least a part of a communication service function that can be provided are connected by a line, the plurality of packet switches are connected at the same level. A station control information table in which each type of packet switch having a communication service function is classified, each is a subnetwork, and information for identifying a corresponding subnetwork is set corresponding to each of all the packet switches.
(1) and communication service function information on communication service functions that can be provided when it is assumed that communication is performed between a packet switch classified in one subnetwork and a packet switch classified in another subnetwork, The communication service provision information definition table (2) set for each combination of the sub-networks is stored and held in the storage device of each packet switch, and the packet switch accommodating the call data terminal receives the call data from the call data terminal. At the time of a communication request, the identification information of the sub-network involved in the communication is extracted from the station control information table (1) (ST1), and based on the extracted identification information of the sub-network, the communication service provision information definition table (2) (ST2), and extracts the communication request from the outgoing data terminal. Determine whether the communication service is acceptable in light of the available communication service function information (ST3)
A communication availability determination method in communication between different types of packet exchanges, characterized in that: