When did Memory- and IO Protection Emerge (Esp. in Minis)?

Erik Baigar erik at baigar.de
Tue May 3 12:55:34 CDT 2016

On Tue, 3 May 2016, Paul Koning wrote:
> No, the PDP-11 offered this starting with the 11/45, in 1971.

OK, that is a hint - the 11/45 also had a MMU and obviosly must
have been a great machine for multi-user stuff.

> In larger computers the feature is much older.  Consider the CDC 6600 
> (1964).  While not all the properties you mentioned apply because I/O is 
> in separate peripheral processors, the notion of a privileged mode and 
> address mapping is there.  And even that isn't the oldest example, I

I have been aware, that  bigger machines offered this already
and therefore I explicitly asked for "Minis"... But yes, the CDCs
are very impressive machines!!!

    Thanks for your reply,


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