04771417 is referenced by 30 patents and cites 3 patents.

A modem is disclosed having a data transmission protocol involving lower-speed, full-duplex operation during the connect sequence with a remote modem and an automatic switch to higher-speed, half-duplex operation for data transfer. Further, the modem data transmission involves transparently changing between lower-speed, interactive operation and higher-speed operation based upon transmission demands. The operation is controlled by a processor monitoring the contents of a transmit data buffer and providing a mode control command to the modem transmitter. The modem also adapts its speed to the quality of the telephone line by fallback or fallforward to a different speed based upon predetermined data frame retransmission criteria.

Title
High speed modem
Application Number
6/909012
Publication Number
4771417
Application Date
September 18, 1986
Publication Date
September 13, 1988
Inventor
Fred G Smith
Longwood
FL, US
Venkat Prasad
San Jose
CA, US
Harunori Yoshikawa
Cupertino
CA, US
Karl J Zorzi
Pleasanton
CA, US
Ronald K Maxwell
Palo Alto
CA, US
Agent
Arnold White & Durkee
Assignee
Racal Data Communications
CA, US
IPC
H04J 15/00
H04B 3/12
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