JPH06188914A - Communication processing system - Google Patents

Abstract

PURPOSE:To perform communication between a packet terminal and non-packet terminals subjected to multipoint connection without providing a special protocol as the high-order layer of CCITT recommendation. CONSTITUTION:A host computer 1 puts a logical channel number and the terminal identification number of a polling destination on a call originating packet to transmit them to a PAD device 3, and they are set in a table in the PAD device 3. The PAD device 3 takes out the terminal identification number from the table and sets a polling flag and adds the terminal identification number to a frame to transmit it to non-packet terminals. Non-packet terminals send data to the PAD device 3, and the PAD device 3 converts the data to a packet and transmits it to the host computer 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication processing system which enables communication between a packet terminal connected to a packet switching network and a non-packet terminal connected in multiple points via a packet assembling / disassembling apparatus.

[0002]

2. Description of the Related Art The packet switching system is a system for transmitting data collectively in packet units. Twenty-five protocols are specified. That is, a logical channel is set between DTEs (data terminal devices) via a network, and when a call request is made, a logical channel number and a DTE address are sent to the network in a call packet. When the connection with the partner terminal is completed, the packet is transmitted to the partner terminal only by specifying the logical channel number.

By the way, there is a communication system in which polling and data transfer are sequentially repeated for a plurality of terminals connected in multipoint. In the above packet switching system, a packet assembling / disassembling device is connected. Non-packet terminals cannot make multipoint connections.

Therefore, as a communication method for terminals capable of multipoint connection via a packet switching network, I
There is a BM LLC protocol. This method uses CCITT Recommendation X.264 as a network layer. Twenty-five protocols are used, a dedicated protocol called QLLC is set as the upper sublayer, and the terminal identifier of the polling partner is transmitted by this QLLC protocol.

[0005]

However, since the above-mentioned QLLC protocol is a dedicated protocol, the packet terminal is limited to a specific one, or it is difficult to apply a general packet terminal. There is.

The object of the present invention is to provide CCITT Recommendation X. 25
It is to provide a communication processing method that enables communication between a packet terminal and a non-packet terminal that is multipoint-connected without providing a special protocol as an upper layer.

[0007]

To achieve the above object, according to the present invention, a packet terminal connected to a packet switching network system and a non-packet terminal multi-point connected via a packet assembling / disassembling apparatus are provided. In the inter-communication processing method, the packet terminal adds the terminal identification information of the polling destination to the calling packet and transmits it to the packet assembling / disassembling apparatus at the time of call setup.

[0008]

When the call is made, the packet terminal puts the terminal identifier of the polling destination in the call packet and transmits it to the packet assembling / disassembling apparatus via the packet switching node. The path is set and its identifier is registered in a table (polling list) for registering a polling destination in the packet assembling / disassembling apparatus. The packet assembling / disassembling apparatus sequentially polls the non-packet terminals and transmits / receives data between the packet terminals and the non-packet terminals according to the polling list.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be specifically described below with reference to the drawings. As mentioned above, CCITT Recommendation X. Two
Reference numeral 5 is provided with an address section for transmitting and receiving a DTE address of a calling packet used at the time of call setup as address information between packet terminals, and a facility section for setting an extended address facility defined as an optional user facility. In addition, the outgoing packet contains
A call user data section is provided to which user information can be added when making a call request, and this area can also be used as a means for transmitting information between packet terminals.

In addition, X. The communication mode of No. 25 is called a virtual call, that is, a method of always setting a logical channel at the time of communication and disconnecting the logical channel at the end of communication is adopted. Then, the address information (DTE
The address) is transmitted only when the virtual call is set up, and after the call is set up, the data packet is transferred on the virtual call.

The present invention relates to the above-mentioned X. Focusing on the 25 protocol, when a packet terminal makes a call to a packet assembling / disassembling apparatus (hereinafter referred to as a PAD apparatus), the corresponding terminal line is specified by the DTE address, and the extended address facility or the call user data section is used to identify the terminal. Send the identifier. This makes it possible to specify the polling destination terminal at the time of call setup and set the logical channel number and the logical path of the polling destination terminal.

In the communication after the call setup, terminal identification is not required between the packet terminal and the terminal under the PAD device, and the packet terminal and the PAD device communicate with each other by the logical channel number, and the PAD device and the PAD device communicate with each other. The non-packet terminals can communicate with each other by using the terminal identifier received from the packet terminal during call setup.

FIG. 1 is a diagram showing the configuration of a network system according to the present invention. In FIG. 1, 1 is a host computer which is a packet terminal, 2 is a packet switching network composed of one or more packet switching nodes and a PAD device 3, and 4 is a non-point connected to the PAD device 3 by multipoint connection. Packet terminals (T1 to Tn) are provided between the host computer 1 and the PAD device 3, and X. Two
The PAD device 3 and the non-packet terminals 4 (T1 to Tn) communicate with each other according to the H.5 protocol, and perform communication according to the HDLC-UNC procedure.

In the present invention, the PAD device 3 and the non-packet terminal 4 have a one-to-n multipoint connection configuration. Therefore, when communication is performed between the host computer 1 and the non-packet terminal 4, a table as shown in FIG. 2 is prepared in the PAD device 3 and the host computer 1 and the non-packet terminal 4 are used by the table. Has set the correspondence between.

That is, in FIG. 2, the table includes logical channel numbers (L1 to Ln) and terminal identifiers (N1 to Nn).
n), a valid / invalid flag (F1 to Fn), and a polling instruction flag (P1 to Pn).

The correspondence between the logical channel numbers (L1 to Ln) and the terminal identifiers (N1 to Nn) is based on the contents of the extended address facility in the calling packet transmitted from the host computer 1 for call setup. It is set every time you do.

FIG. 3 shows the format of a calling packet, which includes a packet header including a logical channel number, D, and the like.
It is composed of a TE address part, an extended address facility part, and a call user data part.

Valid / invalid flags (F1 to F in the table)
n) is a flag indicating whether or not the PAD device 3 polls the terminal 4, and while the call between the host computer 1 and the PAD device 3 is set, it is displayed as valid and the call is released. Inside is displayed invalid.

The polling flag (P1 to Pn)
Indicates that the terminal 4 for which this flag is set is currently being polled, and the flags P1 to Pn are not set at two locations at the same time.

The operation of the present invention will be described below. It is now assumed that T1, T2 and T3 are multipoint connected as the terminal 4 and the host computer 1 polls the terminals T1 and T2. In order to set the logical channel with the terminal T1, the host computer 1 puts the logical channel number L1 and the terminal identification number N1 of the polling destination in the calling packet and transmits it to the PAD device 3, and similarly.
In order to set the logical channel with the terminal T2, the logical channel number L2 and the terminal identification number N2 are carried in the calling packet and transmitted to the PAD device 3.

As a result, in the table of the PAD device 3, L1 and L2 are set as logical channel numbers, and N1 and N2 are set as terminal identification numbers. Therefore, the terminal T3 is not the target of polling, and unnecessary polling is not performed for terminals for which no logical path is set.

Then, the PAD device 3 first extracts the terminal identification number N1 from the table and polls the flag P1.
Flag is set, the terminal identification number N1 is added to the frame, and the frame is transmitted to the terminal T1. If there is data to be transmitted to the terminal T1, the data is transmitted to the PAD device 3. PA
The D device 3 converts the terminal identification number N1 in the received frame into a logical channel number L1, assembles the data into a packet, and transmits it to the host computer 1. When this transmission is completed, the valid / invalid flag F1 is set to invalid and the polling flag P1 is reset.

Next, the PAD device 3 takes out the terminal identification number N2 from the table, sets the flag of the polling flag P2, adds the terminal identification number N2 to the frame and transmits it to the terminal T2, and the terminal receives the data. For example, it is transmitted to the host computer 1 as described above.

When data is transmitted from the host computer 1 to the terminal 4, the host computer 1
PAD the logical channel number, terminal identification number, and data
This is performed by transmitting the data to the device 3, and the PAD device 3 transmits the received terminal identification number and data to the terminal 4.

FIGS. 4A and 4B are diagrams showing the configuration of another embodiment of the present invention, which is the configuration at the time of failure backup. That is, in (a), when a failure occurs in the PAD device 1, the line changeover switch S causes the terminal (T
1-Tn) is an example in which the connection with the PAD device 2 is switched to, and (b) is a case where a failure occurs in the PAD device 1, the PAs are switched by the line changeover switches S1 to Sn.
This is an embodiment in which the connection with the terminals (T1-Tn) is switched from the multipoint connection to the one-to-one connection configuration while switching to the D device 2.

In the above embodiment, the communication protocol between the non-packet terminal and the PAD device is HDLC-UN.
Although the C procedure has been described as an example, the present embodiment is not limited to this, and can also be applied to a basic procedure that takes a multipoint mode or a point-point type communication protocol. As a packet terminal,
It is also applicable to terminals other than the above-mentioned host computer, distributed processing devices, and the like.

[0027]

As described above, according to the present invention, at the time of call setting, the packet terminal adds the terminal identification information of the polling destination to the outgoing call packet and transmits it to the packet assembling / disassembling apparatus. X. It is possible to communicate between a packet terminal and a non-packet terminal that is multipoint-connected without setting a special protocol in the upper layer of 25.

Since the start of polling for the setting destination terminal is determined at the time when the call is set, unnecessary polling is not performed for the terminal for which the logical path has not been set. Furthermore, since the polling destination terminal identifier is set in the table at the time of call setting, the terminal identifier is set to P
There is no need to set it in advance in the AD device, and as a result,
It is possible to easily change the network definition when changing the configuration such as increasing or decreasing terminals or relocating.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a network system of the present invention.

FIG. 2 is a configuration of a table provided in the packet disassembling and assembling apparatus of the present invention.

FIG. 3 is a diagram showing a format of a calling packet.

4A and 4B show the configuration of another embodiment of the present invention.

[Explanation of symbols]

 1 host computer 2 packet switching network 3 packet disassembling and assembling device (PAD device) 4 non-packet terminal

Claims (1)

[Claims] 1. In a communication processing method between a packet terminal connected to a packet switching network system and a non-packet terminal multi-point connected via a packet assembling / disassembling apparatus, at the time of call setup, the packet terminal is: A communication processing method characterized in that terminal identification information of a polling destination is added to a calling packet and transmitted to the packet assembling / disassembling apparatus.