Page 102 - slides.dvi

If
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we
Some
Operating
files
user
share
share
protection
have
could
memory
Systems
and
access
groups
a
usually
is
and
bounds
—
separate
Protection
relocation
etc
have
one
facilities
easy.
mechanisms
single
of
Protection
control
.
and
.
(for
address
we
checking
supervisor
exchange
list
user
several
management
each
but
hardware
have
in
data
levels
(e.g.
spaces
Sharing
economic
machine
hardware
already
practice
with
we
MULTICS
(application
reasons)
no
come
want
rings)
across:
to:
network
requirement)
connection
in
a
locked
room
then
98