Computer network capable of accessing file remotely between computer systems

• US 5,239,648 A
• Filed: 09/19/1991
• Issued: 08/24/1993
• Est. Priority Date: 09/21/1990
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Nukui, Harumi
• Primary Examiner(s): Fleming, Michael R.
• Assistant Examiner(s): Ray, Gopal C.
• Application Number:
  US07/762,456
• Time in Patent Office: 705 Days
• Field of Search: 395/725, 395/575, 395/425, 395/200, 395/325, 395/600, 380/4, 380/25, 380/49, 380/23, 235/380, 235/382, 340/825.31, 340/825.34, 379/95
• US Class Current: 707/770
• CPC Class Codes: G06F 21/6236 between heterogeneous systems
• CPC Class Codes: G06F 2221/2141 Access rights, e.g. capability lists, access control lists, access tables, access matrices
• CPC Class Codes: Y10S 707/922 Communications
• CPC Class Codes: Y10S 707/959 Network
• CPC Class Codes: Y10S 707/99942 Manipulating data structure, e.g. compression, compaction, compilation

Abstract

Each computer system of the computer network according to the present invention has a management information storage portion for storing information with respect to an access authority in accordance with an owner ID and a conversion rule storage portion for storing a rule for converting the formats of a user ID and an access authority. Each computer system adds a machine ID to a user ID and sends the resultant ID to another computer system when a remote access request is issued. In addition, the computer system determines whether or not the formats of the user ID and the access authority being received accord with those of a local computer system when a remote access is accepted. The computer system converts the formats of the user ID and the access authority being received into those of the local computer system in accordance with a predetermined conversion rule when the formats of the local computer system are not matched with those on the remote computer system. Thereafter, the computer system compares the user ID and the access authority whose formats have been converted with information of the access authority stored in the access authority storage portion and determines whether or not to execute the remote access.

Claims

1. A computer network, where a plurality of computer systems are connected through a communication medium, each computer system being capable of accessing files of another computer system, each computer system being given a specific machine ID, each computer system having set kinds of file operations per file, each file being given a specific file ID, and a format of the file ID being set per computer system, comprising:

a computer system accessing the file, including

means for adding the machine ID to the file ID of the requested file when access to the file of another computer system is requested; and

means for sending the file ID and the added machine ID to the other computer system; and

a computer system whose the file is accessed, including

a first table storing correspondence relationships between the kinds of file operations in the computer accessing the file, and the kinds of file operations in the computer whose the file is accessed;

a second table storing correspondence relationships between the format of the file ID in the computer accessing the file, and the format of the file ID in the computer whose the file is accessed;

a third table storing the file ID and the kinds of capable operations per file;

means for receiving the file ID and the added machine ID from the computer system accessing the file;

means for discriminating the computer system whose file is accessed based on the machine ID received by the receiving means;

first determination means for determining whether the kinds of file operations of the discriminated computer system coincide with the kinds of file operations of the computer system whose file is accessed;

first conversion means for, when the kinds of the two computer systems do not coincide with each other, converting the kinds of file operations system to the kinds of file operations of the computer system whose file is accessed in accordance with the first table;

second determination means for determining whether the format of the file ID of the discriminated computer system coincides with the format of the file ID of the computer system whose file is accessed;

second conversion means for, when the formats of the two computer systems do not coincide with each other, converting the format of the file ID system to the format of the file ID of the computer system whose file is accessed in accordance with the second table; and

means for judging whether the requested access is allowed based on comparison of the converted file ID and the converted kinds of file operations with the file ID and the kinds of file operation stored int eh third table.

2. The computer system of claim 1, the computer system accessing the file, further including:

means for determining whether the file, to which access is requested, exists in the computer system accessing the file; and

for, when the file does not exist, sending the file ID and the added machine ID to the other computer machine by the sending means.

3. The computer system of claim 1, wherein the kinds of file operations are reading, writing, deleting, moving, and executing a file.

4. The computer system of claim 1, wherein a difference in the format of file ID is a difference in the number of bits per frame.

5. A computer network, where a plurality of computer systems are connected through a communication medium, each computer system being capable of accessing files of another computer system, each computer system being given a specific machine ID, each computer system having set kinds of file operations per file, each file being given a specific file ID, comprising:

a computer system accessing the file, including

means for adding the machine ID to the file ID of the requested file when access to the file of another computer system is requested; and

means for sending the file ID and the added machine ID to the other computer system; and

a computer system whose the file is accessed, including

a first table storing correspondence relationships between the kinds of file operations in the computer accessing the file, and the kinds of file operations in the computer whose file is accessed;

a second table storing the file ID and the kinds of capable operations per file;

means for receiving the file ID and the added machine ID from the computer system accessing the file;

means for discriminating the computer system whose file is accessed based on the machine ID received by the receiving

means for determining whether the kinds of file operations of the discriminated computer system coincide with the kinds of file operations of the computer system whose the file is accessed;

means for, when the kinds of the two computer systems do not coincide with each other, converting the kinds of file operations to the kinds of file operations so the computer system whose file is accessed in a accordance with the first table; and

means for judging whether the requested access is allowed based on comparison of the converted kinds of file operations and the sent file ID with the file ID and the kinds of file operations stored int eh second table.

6. The computer system of claim 5, wherein the computer system accessing the file, further includes

means for determining whether the file, to which access is requested, exists in the computer system accessing the file;

and for, when the file does not exist, sending the file ID and the added machine ID to the other computer machine by the sending means.

7. The computer system of claim 5, wherein the kinds of file operations are reading, writing, deleting, moving, and executing a file.

8. A computer network, where a plurality of computer systems are connected through a communication medium, each computer system being capable of accessing files of another computer system, each computer system being given a specific machine ID, each file being given a specific fie ID, a format of the file ID being set per computer system, comprising:

a computer system accessing the file, including

means for adding the machine ID to the file ID of the requested file when access to the file of another computer system is requested; and

means for sending the file ID and the added machine ID to the other computer system; and

a computer system whose file is accessed, including

a first table storing correspondence relationships between the format of the file ID in the computer accessing the file, and the format of the file ID in the computer whose file is accessed;

a second table sorting the file ID per file;

means for receiving the file ID and the added machine ID from the computer system accessing the file;

means for discriminating the computer system whose file is accessed based on the machine ID received by the receiving means;

means for determining whether the format of the file ID of the discriminated computer system coincides with the format of the file ID of the computer system whose file is accessed;

means for, when the formats of the two computer systems do not coincide with each other, converting the format of the file ID to the format of the file ID of the computer system whose file is accessed in accordance with the first table; and

means for judging whether the requested access is allowed based on comparison of the converted file ID with the file ID stored in the second table.

9. The computer system of claim 8, wherein the computer system accessing the file, further includes

means for determining whether the file, to which access is requested, exists in the computer system accessing the file;

and for, when the file does not exist, sending the file ID and the added machine ID to the other computer machine by the sending means.

10. The computer system of claim 8, wherein a difference in the format of file ID is a difference in the number of bits per frame.

11. A method for accessing a file in a computer network, where a plurality of computer systems are connected through a communication medium, each computer system being capable of accessing files of another computer system, each computer system being given a specific machine ID, each computer system being set kinds of file operations per file, each file being given a specific file ID, a format of the file ID being set per computer system, comprising the steps of:

in the computer system accessing the file,

adding the macing ID to the file ID of the requested file when access to the file of another computer system is requested; and

sending the file ID and the added machine ID to the other computer system; and

in the computer system whose file is accessed, having a first table storing correspondence relationships between the kinds of file operations in the computer accessing the file, and the kinds of file operations in the computer whose file is accessed;

a second table storing correspondence relationships between the format of the file ID in the computer accessing the file, and the format of the file ID in the computer whose file is accessed; and

a third table storing the file ID and the kinds of capable operations per file,

receiving the file ID and the added machine ID from the computer system accessing the file;

discriminating the computer system whose file is accessed based on the machine ID received by the receiving means;

determining whether the kinds of file operations of the discriminated computer system coincide with the kinds of file operations of the computer system whose the file is accessed;

converting the kinds of file operations of the discriminated computer system to the kinds of file operations of the computer system whose file is accessed in accordance with the first table, when the kinds of the two computer systems do not coincide with each other;

determining whether the format of the file ID of the discriminated computer system coincides with the format of the file ID of the computer system whose file is accessed;

converting the format of the file ID system to the format of the file ID of the computer system whose file is accessed in accordance with the second table when the formats of the two computers systems do not coincide with each other; and

judging whether the requested access is allowed based on comparison of the converted file ID and the converted kinds of file operations with the file ID and the kinds of file operations stored in the third table.

12. The method of claim 11, wherein the computer system accessing the file, is the further step of:

determining whether the file, to which access is requested, exists in the computer system accessing the file; and

for, when the file does not exist, sending the file ID and the added machine ID to another computer machine by the sending means.