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

Multiprogramming, ? FREE ASSOCIATION ASSIGNMENTS of multiprograming

? FREE ASSOCIATION ASSIGNMENTS of multiprograming

Define a layer that is not of an io management module, Define a layer that ...

Define a layer that is not of an IO management module  MCS that is Management Control System is not of an IO management module

What are the operations of a directory, Operations that are to be performed...

Operations that are to be performed on a directory are Search for a file: We are able to find all files whose names match a exact pattern. Create a file: New files requi

How file record length should be chosen, How File record length should be c...

How File record length should be chosen File record length should be selected to match the data characteristics

Evicting pages from physical memory, When do we write a page from physical ...

When do we write a page from physical memory back to the disk? In general, caches have two broad types of writing policies. One approach is a write-through cache. In this case,

Protection, protection in operating system

protection in operating system

What is long-term, What is long-term, medium-term, short-term? In a bat...

What is long-term, medium-term, short-term? In a batch system many processes are submitted than are able to be executed immediately. These processes are reel to a mass storage

Pthreads, A thread is defined as an independent stream of instructions that...

A thread is defined as an independent stream of instructions that can be scheduled to run as such by the operating system. Each program contains a number of threads which can be ru

Compute how many disk input - output operations are required, Q. Consider ...

Q. Consider a file at present consisting of 100 blocks. Presume that the file control block (and the index block in the case of indexed allocation) is already in memory. Compute h

What is the use of FIFOs in client-server applications, What is the use of ...

What is the use of FIFOs in client-server applications

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