KR100213475B1 - Method of realizing a videotex service for providing an image information - Google Patents

Abstract

The present invention relates to a method for implementing a videotex server. In order to meet expectations, a small information provider can design a server suitable for small machines by storing and retrieving information using a file system of UNIX. .

The server according to the present invention checks whether there is data to be received or data to be transmitted after initialization, and if there is data to be received, receives it, analyzes a channel, determines whether it is data for an application program module, and receives data if it is going to an application program. It transfers the data to the message queue or transmits the corresponding frame after searching the tree. If there is data to be transmitted, it receives the data from the message queue and analyzes the channel and transmits the data to the appropriate port.

Description

Implementation Method of Videotex Server for Image Information

1 is a diagram schematically showing the configuration of a videotex system.

2 is a flowchart illustrating a function performance process of a videotex server according to the present invention.

3 is a view briefly illustrating a data flow in an input / output module constituting a server.

4 is a view showing in detail the data flow in the input processing module.

5 is a view showing in detail the data flow in the output processing module.

6 is a state transition diagram of a videotex server according to the present invention.

7A and 7B show a message symbol table and a state symbol table of a server.

8 shows a state transition table of a server.

9A to 9C show function tables, page tables, and page table indexes, respectively.

* Explanation of symbols for main parts of the drawings

10: Videotex Server 20: Videotexture Terminal

30: telephone network 40: packet network

50: network connection pad 60: protocol converter

70: database

The present invention relates to a method of realizing a function of a videotex server for providing a videotex service. More specifically, the present invention relates to an Intel 80386 or 80486 employing UNIX as an operating system. The present invention relates to a method for providing a videotex service in a system at the same level as the system.

The videotex system has functions similar to the general information providing system, but between them, the general information providing system only provides information in the form of text, while the videotex system uses images, graphics and text forms. There is a difference that can provide a variety of information.

Accordingly, the videotex system can effectively meet the increasing demands of information users compared to the general information providing system.

In addition, the Videotex system provides an environment in which a plurality of users can share various information at the same time by using a database, thereby providing a wide variety of services to users quickly.

However, as the structure of supply and demand of information is becoming more advanced, in the form of information supply, when a specific provider manages all the information intensively, a huge amount of capital is required and it can cope with the supply of rapidly changing information efficiently. There is no situation.

Therefore, there is a need for many small information providers who can supply various information quickly to meet the demand for rapidly changing information.

However, from the standpoint of each small information provider, the amount of information they have is very small compared to the centralized information management system described above, and the capital is also small. Using the Videotex server as it is not only uneconomical, it also causes problems that can't take full advantage of the server's information management capabilities.

Therefore, a small server is essential for a small information provider who is doing business to provide a small videotex service.

An object of the present invention is to provide a method for implementing a videotex server suitable for a small machine.

Another object of the present invention is to manage information about each user so that a plurality of users can be provided with the service at the same time.

It is still another object of the present invention to provide a videotex server implementation method using a UNIX file system for storing and retrieving data.

In order to achieve the above objects, the videotex serving method according to the present invention comprises the steps of initializing and scheduling various tables and queues, whether there is data to be input or whether there is data to be output. Examine the channel, and if there is incoming data, analyze the channel and if the incoming data is found to be delivered to the application program, transfer the data to the message queue, or tree And searching for and transmitting the corresponding frame to the user side, and receiving the data from the message queue if there is outgoing data, analyzing the channel, and transmitting the data to the user side.

A videotex server according to the present invention will now be described with reference to the accompanying drawings.

FIG. 1 shows the overall configuration of a videotex system according to the present invention. The videotex system according to the present invention is based on a 386 or 486 system using UNIX as an operating system, a X.25 server for a telephone network, and a public network. It consists of additional communication devices that support the protocol (Multix 25).

In FIG. 1, reference numeral 10 denotes a videotex server, 20 is a videotex terminal, 30 is a public switched telephone network (PSTN) connected to the videotexterminal 20, 40 Is a packet switched data network (PSDN), 50 is a pad (PAD) connecting the telephone network 30 and the packet network 40, and 60 is a data exchange server 10 and the packet network 40 to exchange data. A protocol converter that adapts the sender's communication protocol to the corresponding part of the receiver's protocol.

Looking at the software structure of the videotex system according to the present invention, there are largely four modules (see FIG. 1), that is, the communication module 11, the information management module 12, the videotex application programming interface ( 13), consisting of an application program module 14, the function of these modules is as follows.

First, the communication module 11 is a part related to the network, and can be connected to the X.25 public network and also supports asynchronous multiple communication. Thus, by connecting with X.25 public network, many users can be provided with information service at the same time, and by providing asynchronous direct communication, it provides environment to connect terminal to Videotex system directly.

In addition, the module provides input / output APIs to support application programs, making it easy to write application programs needed by information providers.

The information management module 12 may use a commercial database 70. However, in this case, since the efficiency (processing speed) of information processing decreases, the information management database of the small videotex system is constructed as a file system of UNIX. It enables to provide the functions required for Videotex Server such as information retrieval quickly.

Unlike normal ASCII data, Videotex handles character information including graphics, so an API that can handle videotex representation codes is required to provide an application program.

Accordingly, the videotex server 10 of the present system provides an API 13 for videotex in the form of a C library so that system operators can easily use NAPLPS (North America Presentation Level Protocol Systax) for application programs.

On the other hand, the API 13 also provides a utility for utilizing the data stored in ASCII form as it is.

In general, the Videotex server can provide many kinds of services. In the Videotex server 10, the X.400 MHS (Message Handling System) is mainly adopted, such as a bulletin board system and an electronic mail. Application programs for message transmission, etc., which are implemented using the API 13 of the present Videotex Server 10.

2 is a flowchart illustrating a function of a videotex server according to the present invention, which will now be described in detail with reference to the videotex service according to the present invention.

In functional terms, the software for building the Videotex server 10 can be divided into three parts, the first part of which is responsible for communication with the outside and the second part of the tree navigation. The last part is the part that connects application programs and external communication modules.

The work performed by the main process of the communication software first initializes the tables and queues to be used and then performs scheduling (S11).

By scheduling, the input processing part and the output processing part are performed alternately. The input processing module receives packets from the tty port of the system and performs processing corresponding to its type, or provides a tree search function, Or it is responsible for the delivery of a predetermined packet to the desired application process (application process), the output processing module is responsible for receiving the packet from the application process and sending it to the tty port. The packet types used by the multi-network X.25 protocol to send and receive data with the server are shown in Table (A) in Figure 7.

Depending on the type of packet, a change of state managed by the main process occurs or data is transferred.

The channel access management state managed by the main process is defined and shown in FIGS. 6 and 8. The state transition table of FIG. 8 shows the state analysis in the data flow diagrams of FIGS. It is included in the F-table (function table) referenced by the routine to manage its state.

Referring to the state transition diagram of FIG. 6, the general data transmission is performed in the connected state, and the busy data is prevented in order to prevent overflow due to a large amount of incoming data than the amount of a channel processing data. Use packets.

When a busy packet is sent to the other party (from X.25 public network to main process, or from main process to X.25 public network), the receiving party retains data to send to the channel until it receives an avail packet. You are holding.

In this videotex system, as shown in Fig. 7b, Local Hold is defined as S2 sending busy packets from the server side, and Remote Hold is sending busy packets from the X.25 multiplex network side. It is defined as (S3).

The state before the connection is terminated or started is defined as an idle state S0. After receiving Call and Call_confirm messages, the state is switched to the connected state S1.

These states exist one for each channel, and the main process manages them in table form.

The tables used by the X.25 public network and the server to exchange data include function tables (F_table), page tables, and page table indexes. Referring to FIGS. 9A to 9C, A detailed description of these functions is as follows.

First, the function table (see Fig. 9a) is a table that defines the function according to the current connection state, and the function routines to be called according to each state are defined.

The page table (see Figure 9b) is used to support tree navigation. The Name item is the name of the logical frame, and the Type item is the property of the page. This item defines the page having general screen information or action pages that should execute external application program.

In this case, when the Type item is an execution page, the content to be included in the name item is the name of the application program.

The Keyword item is used to show the page corresponding to the keyword when the user requests a keyword search. Next and Help items indicate the page to go to when the Next and Help Keys are pressed. The send item (Send [1] .... [9]) indicates the page to go to when the user dials the number and executes the key, and the error item indicates the page to go to when an incorrect entry is made. Finally, CalChoice item defines the page to go to when you press more than 10 times and press the Execute key.

The information contained in one pay table defined as above should include all functions that a single service selected from VAP (Videotex Access Point) should do.

Therefore, since the server can provide various services, the number of page tables existing in the server is equal to the number of services provided by the server.

The page table index (see also 9c) performs the function of providing the address of the page table to be used. In the initial operation, the page table name that defines the services provided by the server is read and the corresponding page table is read. When you create it, it points to the address of the table.

3 schematically shows the data flow between main modules in the main process during scheduling after initializing.

In FIG. 2, steps S13 to S20 show step by step performing the function of the input processing module, and steps S22 to S24 show step by step performing the function of the output processing module.

4 and 5 show the data flow of the input processing module and the data flow of the output processing module in more detail.

When the initialization and scheduling is completed, the get packet routine (GET PACKET routine) reads data from the tty port, and the routine checks whether the data to be read exists in the tty port (S12). If there is data to be read, the data is accepted (S13), when a call request packet is received, the channel of the packet is analyzed, and the user data field item is checked to confirm the VAP (Videotex Access Point). First, it is checked whether the requested service of the user provided by the server is provided by the server, and if the corresponding information is stored in the UCB (User Control Block) for the channel (Page tabel Index) is stored (S14).

Then, it is determined whether the received data packet goes to the application program module (S15), and if it goes to the internal application module, the data packet is transferred to the message queue (S16). (See Figure 4).

If the received data packet does not go to the application program module, a tree search routine is executed (S17).

The tree navigation routine of the input processing module (see FIG. 4) is responsible for displaying graphic information of the screen unit, which is a characteristic of Videotex, and the main functions will be described in detail as follows.

The tree search routine has a Key Pad analysis function that analyzes key values entered by the user, and reads the logical frame names requested by the user keypad, and displays the corresponding physical frames. Frame send function to find and transmit, path saving function to push the path of pages shown by next key, execution key, etc. for each user to stack, and action after specified time It provides a timer function to make this happen.

In addition to the functions described above, a function that calls an external application is also required. This function is provided by an INVOKE CHILD routine.

After the tree search (S17) is completed, it is determined whether the searched page is a program to be executed du (S18), and if it is found to be a program to be executed, the program is executed (S19).

If there is no program to be executed after the tree search (No in step S18), a frame corresponding to the result of the tree search is transmitted to the tty port (S20).

If there is data to go out to the tty port (YES in S21), the data is received from the message queue (S22), the channel is analyzed (S23), and the data received from the message queue is transmitted to the corresponding channel (S24). .

Input processing and output processing of the server as described above continue until an instruction to end (S25).

As described above, the videotex server according to the present invention is designed to be suitable for a small model using a UNIX file system without using a commercial database. The service business can be used, and existing telephone network (PSTN) and packet network (PSDN) can be used as it is, so that multiple users can use it at the same time.

Claims (1)

A method of performing a function of a server in a videotex system for providing image information, the method comprising: initializing and scheduling various tables and queues, whether there is data to be received from a port, and whether there is data to be transmitted to the port. Investigating, if there is data to be received from the port, analyzing the channel after receiving the data, and determining whether the received data is data for an internal application program module, and the received data is the internal application. If it is determined that the data for the program module is transmitted, the received data is transmitted to the message queue, and if it is determined that the data is not determined, the tree search is performed to determine whether the searched page is an external application to be executed, and if the page is the program to be executed. Run it or And transmitting the transmission data to the port after receiving the transmission data from the message queue and analyzing the channel if there is data to be transmitted. Implementation method of Videotex Server.