Network communication system

• US 6,195,366 B1
• Filed: 04/24/1998
• Issued: 02/27/2001
• Est. Priority Date: 04/25/1997
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Katoh, Eri, Kayashima, Makoto, Terada, Masato, Fujiyama, Tatsuya
• Primary Examiner(s): NGO, RICKY QUOC
• Application Number:
  US09/065,416
• Time in Patent Office: 1,040 Days
• Field of Search: 370/254, 370/257, 370/400, 370/401, 370/410, 370/411, 370/475, 709/201, 709/203, 709/217, 709/218, 709/219, 709/220, 709/221, 709/222, 709/227, 709/228, 709/238, 709/242, 709/245
• US Class Current: 370/475
• CPC Class Codes: H04L 2101/663 Transport layer addresses, e.g. aspects of transmission control protocol [TCP] or user datagram protocol [UDP] ports
• CPC Class Codes: H04L 61/5007 Internet protocol [IP] addresses
• CPC Class Codes: H04L 63/0281 Proxies
• CPC Class Codes: H04L 69/164 Adaptation or special uses of UDP protocol
• CPC Class Codes: H04L 69/165 Combined use of TCP and UDP protocols; selection criteria therefor
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]

Abstract

A method of conducting a connectionless communication in a network communication system including a client, a server, and a plurality of proxy servers which are disposed on a transmission path between the client and server. The communication is accomplished by use of specification of a communication address thereof and a port number dynamically assigned by the computer. (a) The server transmits own communication address and own port number to the client. (b) The client transmits own communication address and own port number as well as the communication address and port number of the server to a first adjacent proxy server computer. (c) The N-th (N≧1) proxy server transmits own communication address and own server side port number as well as the communication address and the port number of the server to an (N+1)-st proxy server. (d) step (e) is repeatedly executed by incrementally increasing N until the (N+1)-th proxy server becomes a terminal proxy server. (e) The terminal proxy server transmits its own communication address and its server and client side port numbers to the N-th proxy server. (f) The N-th proxy server sends own communication address and own client side port number and the communication address and the server side port number of the terminal proxy server to the (N−1)-th proxy server when N≧2 or the client when N=1. (g) step (f) is repeatedly executed by incrementally increasing N until N becomes one. (h) The client transmits a communication address and a server side port number of the proxy server to the server. (i) The connectionless communication is commenced after all computers acquire a communication address and an associated port number of each of the computers adjacent thereto.

Claims

1. A method of conducting a connectionless communication in a network communication system including a client computer, a server computer, and a plurality of proxy server computers being disposed on a transmission path between the client and server computers and forming firewalls in which each computer carries out communication with specification of a communication address thereof and a port number dynamically assigned by the computer, comprising:

step (a) that the server computer transmits own communication address and own port number to the client computer;

step (b) that the client computer transmits own communication address and own port number as well as the received communication address and port number of the server computer to a first adjacent proxy server computer;

step (c) that the N-th proxy server computer (N≧

1) transmits own communication address and own server side port number and the received communication address and port number of the serve computer to an (N+1)-th proxy server computer adjacent thereto on the server computer side;

step (d) that step (c) is repeatedly executed while incrementally increasing N until the (N+l)-th proxy server becomes a terminal proxy server computer;

step (e) that the terminal proxy server computer transmits own communication address and own client side port number as well as own communication address and own server side port number to an N-th proxy serve computer adjacent thereto on the client side;

step (f) that the N-th proxy serve computer transmits own communication address and own client side port number as well as a communication address and a server side port number of the terminal proxy server computer to an (N−

1)-th proxy serve computer adjacent thereto on the client side for N≧

2 or the client computer for N=1;

step (g) that step (f) is repeatedly executed while decrementing N until N becomes one;

step (h) that the client computer transmits the communication address and the server side port number of the terminal proxy server computer to the server computer; and

step (i) that a connectionless communication is commenced after all computers acquire computer addresses and associated port numbers of adjacent computers thereof.

2. A connectionless communication method in accordance with claim 1. wherein the steps (a) to (h) are carried out in a connection-oriented communication.

3. A connectionless communication method in accordance with claim 2, wherein:

the network communication system utilizes TCP/IP;

the connection-oriented communication is carried out by use of TCP; and

the connectionless communication is accomplished by using UDP.

4. A connectionless communication method in accordance with claim 3, wherein:

the communication between the client and server computers are conducted by using a TCP control connection.

5. A connectionless communication method in accordance with claim 1, further including the step of

accomplishing mutual authentication when connection is established between adjacent computers of the steps (b) and (c).

6. A connectionless communication method in accordance with claim 5, further including the step of

conducting an access control when the mutual authentication is completed.

7. A method, in a network communication system including a client computer, a server computer, and a plurality of proxy server computers configuring firewalls, for conducting a connectionless communication in each of the proxy server computers comprising the steps of:

(a) receiving from a client side computer a communication address and a server side port number thereof as well as a communication address and a port number of a server computer;

(b) assigning a connectionless communication port number;

(c-1) when own computer is a terminal proxy server computer,

transmitting own communication address and own client side port number as well as own communication address and own server-side port number to a computer adjacent thereto on the client side;

(c-2) when own computer is other than a terminal proxy server computer,

transmitting own communication address and own server side port number as well as a communication address and a port number of a server computer to a proxy server computer adjacent thereto on the server side;

transmitting own communication address and own client side port number as well as a communication address and a server side port number of a terminal proxy server computer to a computer adjacent thereto on the client side;

(d) storing in a table a communication address and an associated port number of each of computers adjacent thereto on both sides; and

(e) relaying connectionless communication data in accordance with information stored in the table.

17. A computer-readable medium containing instructions for causing a server computer to perform connectionless communication in a network communication system including a client computer, a server computer, and a plurality of proxy server computers configuring firewalls therebetween, by the steps (a) to (e) described in claim 7.

8. A method, in a network communication system including a client computer, a server computer, and a plurality of proxy server computers configuring firewalls, for conducting a connectionless communication in the client computer, comprising the steps of:

(a) receiving from a server computer a communication address and a port number of the server computer;

(b) assigning a connectionless communication port number;

(c) transmitting own communication address and own port number and the communication address and the port number received from the server computer to an adjacent proxy server computer;

(d) receiving a communication address and a client side port number of the adjacent proxy computer and a communication address and a server side port number of a terminal proxy server computer;

(e) transmitting the communication address and the server side port number of the terminal proxy server computer to the server computer; and

(f) commencing a connectionless communication in accordance with received information.

18. A computer computer-readable medium containing instructions for causing a server computer to perform connectionless communication in a network communication system including a client computer, a server computer, and a plurality of proxy server computers configuring firewalls therebetween, by the steps (a) to (f) described in claim 8.

9. A method of conducting a connectionless communication in a network communication system including a client computer, a server computer, and a plurality of proxy server computers being disposed on a transmission path between the client and server computers and forming firewalls in which each computer carries out communication with specification of a communication address thereof and a port number dynamically assigned by the computer, comprising:

step (a) that the server computer transmits own communication address and own port number to the client computer;

step (b) that the client computer transmits own communication address and own port number as well as the received communication address and port number of the server computer to a first adjacent proxy server computer;

step (c) that the first proxy server computer transmits own communication address and own client side port number as well as own communication address and own server side port number to the client computer;

step (d) that the client computer transmits the received communication address and the received server side port number of an N-th proxy server computer (N≧

1) as well as the received communication address and the received port number of the server computer to an (N+1)-th proxy server computer;

step (e) that the (N+1)-th proxy server computer transmits own communication address and own server side port number as well as own communication address and own client side port number via the first to N-th proxy server computers to the client computer;

step (f) that steps (d) and (e) are repeatedly executed by incrementally increasing N until the (N+1)-th proxy server computer becomes a terminal proxy server computer;

step (g) that the client computer transmits a communication address and a server side port number of the terminal proxy server computer to the server computer; and

step (h) that a connectionless communication is commenced after all computers acquire a communication address and an associated port number of each of the computers adjacent thereto.

10. A connectionless communication method in accordance with claim 9, wherein the steps (a) to (g) are carried out in a connection-oriented communication.

11. A connectionless communication method in accordance with claim 10, wherein:

the network communication system utilizes TCP/IP;

the connection-oriented communication is conducted by use of TCP; and

the connectionless communication is achieved by using UDP.

12. A connectionless communication method in accordance with claim 11, wherein:

the communication between the client and server computers are conducted by using a TCP control connection.

13. A connectionless communication method in accordance with claim 9, further including the step of

accomplishing mutual authentication when connection is established between the client computer and the proxy server computer of the steps (b) and (d).

14. A connectionless communication method in accordance with claim 13, further including the step of

conducting an access control when the mutual authentication is completed.

15. A method, in a network communication system including a client computer, a server computer, and a plurality of proxy server computers configuring firewalls, for conducting a connectionless communication in each of the proxy server computers, comprising the steps of:

(a) receiving from a client side computer a communication address thereof and a server side port number thereof as well as a communication address and a port number of a server computer;

(b) assigning a connectionless communication port number;

(c) transmitting own communication address and own client side port number as well as own communication address and own server side port number to a computer adjacent thereto on the client side;

(d) when own computer is other than a terminal proxy server computer,

(d1) relaying data sent from the client computer to a proxy server computer adjacent to the own computer on the server side;

(d2) receiving a communication address and a client side port number of an N-th proxy server computer sent from the adjacent proxy server computer on the server side and a communication address and a server side port number of the N-th proxy server computer and transmitting the received communication addresses and port numbers to an adjacent computer on the client side;

(d3) repeatedly executing the steps (d1) and (d2) while incrementally increasing N until the N-th proxy server computer becomes a terminal proxy server computer;

(e) storing in a table a communication address and an associated port number of each of computers adjacent thereto on both sides; and

(f) relaying connectionless communication data in accordance with information stored in the table.

19. A computer computer-readable medium containing instructions for causing a server computer to perform connectionless communication in a network communication system including a client computer, a server computer, and a plurality of proxy server computers configuring firewalls therebetween, by the steps (a) to (f) described in claim 15.

16. A method, in a network communication system including a client computer, a server computer, and a plurality of proxy server computers configuring firewalls, for conducting a connectionless communication in the client computer, comprising the steps of:

(a) receiving from a sever computer a communication address and a port number thereof;

(b) assigning a connectionless communication port number;

(c) transmitting own communication address and own port number as well as the communication address and the port number received from to the server computer to a first proxy server computer adjacent thereto;

(d) receiving a communication address and a server side port number of the first proxy server computer and a communication address and a client side port number of the first proxy server computer;

(e) transmitting the communication address and the server side port number of the first proxy server computer and the communication address and the port number of the server computer to a second proxy server computer;

(f) receiving a communication address and a server side port number of an N-th proxy server computer (N≧

2) and the communication address and a client side port number of the N-th proxy server computer;

(g) transmitting the communication address and the server side port number of the N-th proxy server computer and the communication address and the port number of the server computer to an (N+1)-th proxy server computer;

(h) repeatedly executing the steps (f) and (g) while incrementally increasing N until the (N+1)-th proxy server computer becomes a terminal proxy server computer;

(i) transmitting the communication address and the server side port number of the terminal proxy server computer to the server computer; and

(j) commencing a connectionless communication in accordance with received information.

20. A computer computer-readable medium containing instructions for causing a server computer to perform connectionless communication in a network communication system including a client computer, a server computer, and a plurality of proxy server computers configuring firewalls therebetween, by the steps (a) to (j) described in claim 16.