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

Synchronization, As we already know, threadsmust ensure consistency; otherw...

As we already know, threadsmust ensure consistency; otherwise, race conditions (non-deterministic results) might happen. Now consider the "too much milk problem": two people share

Explain the alphabet and string, Explain the Alphabet and String A fini...

Explain the Alphabet and String A finite set of symbols is known as alphabet. An alphabet is frequently denoted by sigma, yet can be given any name. B = {0, 1} says B is an

Explain the benefits of thread over process?, BENEFITS OF THREADS OVER PROC...

BENEFITS OF THREADS OVER PROCESS If implemented correctly after those threads have some advantages of (multi) processes, they take: 1. Less time to create a new thread tha

Explain concept of synchronization, Synchronization In communication am...

Synchronization In communication among processes messages passed may be blocking or nonblocking - also called as synchronous and asynchronous. Blocking send : The sending pr

Describe paging technique used in unix systems, Describe paging technique u...

Describe paging technique used in UNIX systems. When a process begin in UNIX, not every its memory pages are read in from the disk at once. In its place, the kernel loads into

Define logical address and physical address, Define logical address and phy...

Define logical address and physical address. An address formed by the CPU is referred as logical address. An address seen by the memory unit that is the single loaded into the

Producer – consumer process, Step by step displays the content, and the fin...

Step by step displays the content, and the final result of the list ("buffer") of 6 elements as the initial values ??and the following elements which are produced (NEXTP) or consum

Explain swapping, Explain Swapping Swapping is a method of temporarily ...

Explain Swapping Swapping is a method of temporarily removing inactive programs from the memory of computer system.

Requirements to satisfied by the critical section problem, What are the req...

What are the requirements to be satisfied by the critical section problem? Following are the necessities to be satisfied by the critical section problem: a)      Mutual exc

Operating system, What criteria are important in choosing a file organisati...

What criteria are important in choosing a file organisation?

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