Abstract: A data telecommunications system and method is provided for sending a data stream of characters in distinct data packets between two units of data terminal equipment (which can be either terminals and/or computers) connected over communication lines. A modem is connected between each unit of data terminal equipment and the communication lines, and one initiating modem includes a means for changing the packet size of the data which is transmitted. The receiving modem checks the packets for errors, and if errors are found, the packet is retransmitted. The initiating modem counts the number of transmissions of data packets as well as the number of retransmissions of data packets. A ratio of retransmissions to transmissions is used to determine the optimum packet size. The packet size is continually subject to change as the ratio changes during transmission.

Abstract: A data telecommunications system and method is provided for sending a data stream of characters between two pieces of data terminal equipment (which can be either terminals and/or computers) connected over communication lines. A modem is connected between each piece of data terminal equipment and the communication lines, and at least one of the modems is capable of operating in both a special mode which provides optimized data transmission and a normal mode which provides direct non-optimized data transmission. Upon detection of a special mode indicating character, a modem of the data telecommunication system of the present invention will establish a link under the special mode protocol. In one embodiment, when a second special character is detected by the modem, the modem is caused to operate in a normal mode. In an alternate embodiment, the modem will store characters in a special buffer memory until either the special mode-indicating character is detected or until the buffer fills.

Abstract: Disclosed is a data telecommunications system and method in which at least one modem which, capable of operating at a variety of transmission speeds, selects the proper speed at which to operate. An initiating modem capable of operating at a plurality of operating speeds compares the maximum operating speed of a receiving modem, and if a match is found, operation begins at that operating speed. If no match is found, operation begins at a default transmission speed.