1986 – Telenet funded a project to develop an improved public domain application to application file transfer protocol. This protocol would alleviate the throughput problems their network customers were experiencing with XMODEM and Kermit file transfers. ZMODEM could provide high performance and reliability over packet switched networks while preserving XMODEM’s simplicity. It made XModem and YModem obsolete. This Day in Tech History podcast show notes for October 14 Chuck Yeager flies the speed of sound ARM 250 is released Apple launched the iPhone 4S Google announced Buzz was shutting down.