The Design and Implementation of Data Transportation through Telephone Line in Linux
Abstract
The purpose of the design is to control the local MODEM to dial remote terminal by telephone line base on Linux operating system. At the same time,it can make the data transmit between two MODEMs to achieve the purpose of data transportation. the MODEM is connected to the computer through the serial port RS-232. Linux can control the serial port of the computer by POSIX termios interface. That can carry out the setting and data reading/writing of the serial port, the data transmit between computers (DTE) and MODEM (DCE), and the control from the computer to the MODEM, namely, the reading/writing of the serial port from the computer.
The author of this paper accomplishes the setting and reading/writing operation, using the AT commands to control the MODEM dialing, and a transport protocols for files. All of these make two PCs send and receive files from the public telephone line by using the MODEM. The design is intended to make the user who has not installed the network to transmit data with others by telephone lines using the 56k MODEM. Compared with the Internet, the telephone line is safer and widely distributed. The design makes use of the universality and the safety of the telephone line.
