From mboxrd@z Thu Jan 1 00:00:00 1970 From: jnc@mercury.lcs.mit.edu (Noel Chiappa) Date: Sun, 31 Dec 2017 18:10:22 -0500 (EST) Subject: [TUHS] OT: Grace Hopper, Unix epoch, ARPAnet converted to TCP/IP Message-ID: <20171231231022.CDC7218C09C@mercury.lcs.mit.edu> > From: Dave Horsfall > the ARPAnet got converted from NCP to TCP/IP in 1983; ... have a more > precise date? No, it was Jan 1. It wasn't so much a 'conversion', as that was the date on which, except for a few sites which got special _temporary_ dispensation to finish their preparations, support for NCP was turned off for most ARPANET hosts. Prior to that date, most hosts on the ARPANET had been running both, and after that, only TCP worked. (Non-ARPANET hosts on the then-nascent Internet had always only been using TCP before that date, of course.) Noel