YMODEM

YMODEM is a file transfer protocol. It belongs to a category of protocols that work on top of an already-established connection, typically a modem connection to a BBS.

As far as we can tell, YMODEM was not particularly popular. This may have been because there were several incompatible variants of it, and/or because of the small window of time between it and the introduction of ZMODEM.

Links

 * YMODEM
 * XMODEM/YMODEM Protocol Reference, Edited by Chuck Forsberg
 * 1988-06-18
 * 1987-10-27
 * 1985-10-10