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- Process may need to dynamically change access rights while executing
(i.e. switch from one domain to another c.f. OS mode with access to privileged
instructions) - Generally needed for OS procedures
- Use access matrix with domains as objects and enter rights to indicate
domain switch can take place
- Another means of dynamically changing protection is to change access matrix itself :
Owner : can add/remove any access right within the column applying to the owned object
Copy : can copy rights marked with * within the column
Transfer : can transfer rights marked with + within column
Control : applies only to domains - A process in domain D2 can add or remove
access rights within the row applying to D4
![figure64](img4.gif)
Figure: Access Matrix
Omer F Rana
Sun Feb 16 17:49:18 GMT 1997