There are 4 fields in the access control section and they are

Valid (1 bit): this bit is set to 1 if the page currently resides in the main memory. When a program generates an access request for a page whose valid bit is 1, translation continues. If the bit is 0, the whole page must be brought into the main memory before the access can proceed

Protection (4 bits): The protection field specifies the access privileges for programs that access the page

Modified (1 bit): The value of this bit is 1 if there has been a Write operation to the page during its current residency period. This information is necessary when a page is to be removed from the main memory. It determines whether the page must be written back into the secondary storage

Own(5 bits): This field provides additional protection information

 

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