Protection scheme in unix, Operating System

Assignment Help:

Q. Consider a system that holds 5000 users. Presume that you want to allow 4990 of these users to be able to access one file.

a. How would you denote this protection scheme in UNIX?

b. Could you propose another protection scheme that is able to be used more effectively for this purpose than the scheme provided by UNIX?

Answer:

a. There are two processes for achieving this:

1. Create an access control record with the names of all 4990 users.

2. Put these 4990 users in one group as well as set the group access accordingly. This scheme can't forever be implemented since user groups are restricted by the system.

b. The universal access to records applies to every user unless their name appears in the access-control list with different access permission. With this scheme you merely put the names of the remaining ten users in the access control list but with no access privileges allowed.


Related Discussions:- Protection scheme in unix

Kernel, 1. What must a kernel provide for an effective user-level thread im...

1. What must a kernel provide for an effective user-level thread implementation? 2. With respect to the quantum q in a scheduling algorithm, explain and discuss the impact of the

What is the use of system calls, Q. What is the use of system calls? A...

Q. What is the use of system calls? Answer: System calls permit user-level processes to request services of the operating system.

Define local procedure call, Q. What kinds of services does the process man...

Q. What kinds of services does the process manager provide? Define local procedure call? Answer: The process manager offers services for creating and deleting and using proce

Define approaches that require knowledge of the system state, Define approa...

Define approaches that require knowledge of the system state?  Answer: Deadlock detection, Deadlock prevention, Deadlock Avoidance.

Operating systems concepts, The code should be nicely formatted with plenty...

The code should be nicely formatted with plenty of comments. It should be easy to read, properly The summary section should include three parts: (1) Record the running t

Explain how protection is provided for the hardware resource, Explain how p...

Explain how protection is provided for the hardware resources by the operating system. Dual mode operation Sharing system resources needs operating system to make sure

Define page fault, Page fault is a trap to the software gained by the har...

Page fault is a trap to the software gained by the hardware when a process accesses a page that is goes in the virtual address space, but not added in physical memory. In the har

Explain system-wide open-file and per-process open-file, Explain system-wid...

Explain system-wide open-file and per-process open-file The system-wide open-file table have a copy of the FCB of each open file, as well as other information. The per-pr

Multilevel queue scheduling, Explain multilevel queue scheduling and multil...

Explain multilevel queue scheduling and multilevel feedback queue scheduling #Minimum 100 words accepted#

Define lru page replacement algorithm, Define LRU Page Replacement Algorith...

Define LRU Page Replacement Algorithm LRU policy: LRU expands to least currently use. This policy suggests which we re- move a page whose last usage is farthest from current ti

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd