A Statistical Model for Console Behavior in Multiuser Computers
The ability of a computer system to communicate
with the outside world efficiently is as important 
as its ability to perform computations efficiently. 
It is quite difficult to characterize a particular 
user, but rather easy to characterize the entire user community.
 Based on the properties of this community 
we have postulated a hypothetical "virtual console."
 No claim is made that a virtual console behaves 
like any actual console, but the entire collection of
virtual consoles models the collection of actual 
consoles.  Using the model we answer questions like: 
How many processes are suspended waiting for console 
input?  What is the maximum rate at which a process can
execute?  What bounds can be set on overall buffer 
requirements?  Answers to these and similar questions
are needed in certain aspects of operating system 
design.
CACM September, 1968
Denning, P. J.
