I just finished reading "Where Wizards Stay Up Late - The Origins of the Internet", and the story of the IMP features heavily in that book. And it describes some of the resiliency features too, including the auto restart, and even auto loading of it's software! Cool stuff. I highly recommend it to anyone who wants to hear more about this time period of the early "internet". Good stuff.
Back then, it was spelled "Internet". Frmr VP Al Gore described it as "the information superhighway" while the late Sen. Ted Stevens called it "a series of tubes."
The transition from BBSes (with UUCP and CompuServe) to dial-up ISPs was tedious. Newsgroups (NNTP), IRC chat, FTP servers, and Gopher search clients were as important as web pages.
And placeholder icons, red-on-yellow scrolling marquee Comic Sans, page visit counters, and blink tags abounded. (Oh, and page rings, broken deep links, and capture auto-redirect pages. That was before the era of pop-under popup pages, embedded plugins (SWF Flash, ActiveX, Java Applets (which could be cryptographically-signed) controls, and sensible browser security controls.)
Around 1996, I wrote a shiny-new HTTP/1.0 (!) CGI chat server in Perl with a HTML-JavaScript client using (inefficient) polling. The client exploited HTTP/1.0 to keep the server connection alive almost indefinitely with periodic no-op messages. The server could push new chat messages by writing them to all N clients.
Later on, on LANs, multicast UDP could sometimes deliver a message to multiple listeners.
Multicast, SCTP, UDP lite, and broadcast don't really scale across the series of tubes. UDP is "best effort" and not guaranteed. UDP's advantage is lower latency. IPv6 will take another 30 years to deploy unless a collective of telcos conspire to phase out IPv4.
Edit 3: I believe I worked with someone who worked with Lauren at UCLA.
Edit 4: The first Internet message from UCLA to SRI was "LO".
