Data communication terminal, proxy device, data communication system, and data communication method

Abstract

The invention provides a data communication terminal, a proxy device, a data communication system, and a data communication method. A technique for easily realizing data communication without limiting the application layer protocol during data communication while maintaining the proxy function. A mobile communication terminal (2) includes a control protocol processing section (203) which transmits an address request to a proxy device (5) to acquire global address information using the HTTP that is preset so as to be used by the mobile communication terminal (2) and the proxy device (5), a TCP / UDP data transmitter / receiver section (205) which establishes a connection with the proxy device (5), and an application section (201) which transmits data via a communication path between the proxy device (5) and a server device (6) using the global address information as the transmitter address. The control protocol processing section (203) transmits information relating to the connection destination of the server device (6) to the proxy device (5) using the HTTP, and requests a connection between the proxy device (5) and the server device (6) using a predetermined transport layer protocol.

Description

technical field [0001] The present invention relates to a data communication terminal, an agent device, a data communication system and a data communication method. Background technique [0002] Conventionally, in data communication using the Internet or the like, a proxy server is used in order to ensure high-speed access and communication security when connecting an internal network such as a data communication network of a specific communication carrier or an intra-company communication network to the Internet. As such proxy servers, HTTP (Hypertext Transfer Protocol) proxies and FTP (File Transfer Protocol) proxies, etc., which are limited application layer protocols usable between terminals and their communication destinations, are widely used. [0003] In contrast, there is known a data communication device capable of realizing data communication using a plurality of application layer protocols (see Patent Document 1 below). This data communication device has a functi...

AI Technical Summary

Problems solved by technology

[0005] However, in the above-mentioned existing proxy devices, there is a tendency that the application layer protocols that can be used on the terminal are limited, and to cope with multiple application layer protocols, it is necessary to replace the proxy device or add a large number of functions

On the other hand, although direct data communication between a terminal and its communication destination is considered without going through a proxy device, since the proxy device also has a conversion function between a private address and a global address, problems such as exhaustion of global addresses may occur , there will also be a problem of reduced communication security

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