Data telecommunications system and method with universal link establishment

Claim 1

A data telecommunications system for enabling data communications between an initiating unit of data terminal equipment and a receiving unit of data terminal equipment over communication lines, said system including an initiating modem connected between said initiating unit and the communication lines and a receiving modem connected between said receiving unit and the communication lines, said system comprising: a first means for modulating data signals transmitted over said communication lines and a first means for demodulating data signals transmitted over said communication lines, both of said first means included in each of said initiating modem and said receiving modem, said first means allowing said modem to transmit data at a low speed (2400 bps or less); a second means for modulating data signals transmitted over said communication lines and a second means for demodulating data signals transmitted over said communication lines, both of said second means being included in said initiating modem and said receiving modem and being separate from said first means, said second means allowing said modem to transmit data at a high speed (4800 bps or greater); means for initially establishing a physical connection between said initiating modem and said receiving modem at said low speed utilizing said first modulating means and said first demodulating means in each of said modems; means for determining whether said receiving modem is capable of operating under a special optimizing protocol; means for establishing operation between said initiating modem and said receiving modem if said receiving modem is capable of operating under said special optimizing protocol; means for switching said physical connection between said initiating modem and said receiving modem utilizing a link layer to a connection at said high speed under said special optimizing protocol utilizing said second modulating means and said second demodulating means in each of said modems.

Claim 9

A method for establishing a data telecommunications connection between an initiating unit of data terminal equipment and a receiving unit of data terminal equipment, each of the units having an associated modem connected between said unit and communication lines, each of said modems including a means to provide operation at a high speed (4800 bps or above) and a means to provide operation and at a low speed (2400 bps or below), said method comprising the steps of: establishing a physical connection between said initiating modem and said receiving modem at the low speed; determining whether said initiating modem and said receiving modem are capable of operating under a special, optimizing matched protocol that provides error detection in a transmitted data stream and automatic retransmission of said data stream when an error occurs; if said initiating modem and said receiving modem are capable of operating under said matched protocol, establishing a link connection between said initiating modem and said receiving modem under said matched protocal and determining a class of operation under said matched protocol; if said class of operation is a class providing operation at a high speed, utilizing said link connection to establish a physical connection between said initiating modem and said receiving modem at said high speed.

Claim 10

A method for establishing a data telecommunications connection between an initiating unit of data terminal equipment and a receiving unit of data terminal equipment, each of the units having an associated modem connected between said unit and communication lines, each of said modems including a means to provide operation at a high speed (4800 bps or above) and a means to provide operation and at a low speed (2400 bps or below), said method comprising the steps of: establishing a physical connection between said initiating modem and said receiving modem at the low speed; determining whether said initiating modem and said receiving modem are capable of operating under a special, optimizing matched protocol that provides error detection in a transmitted data stream and automatic retransmission of said data stream when an error occurs; if said initiating modem and said receiving modem are capable of operating under said matched protocol, establishing a link connection between said initiating modem and said receiving modem under said matched protocal and determining a class of operation under said matched protocol; if said class of operation is a class providing operation at a high speed, utilizing said link connection to establish a physical connection between said initiating modem and said receiving modem at said high speed.