Case Study #3

In a multiprogramming and time-sharing environment, several users share the system simultaneously. This situation can result in various security problems. Name at least two of these problems. Can we ensure the same degree of security in a time-share machine as we have in a dedicated machine? Explain your answer.

Internet Cafe CB

A multiprogramming and time-sharing environment is a type of setting where several users share the system simultaneously and a great example of this kind of setting is in Internet Café. First of all most of the Internet Cafés are of time-sharing environment setting because it is frequently requires a single hardware usage from different computers/users, an example for this hardware is the printer, I do believe mostly the printer is placed close to the cashier or Internet Café Clerk or to a computer that is not frequently used by other users. All you have to do in your own unit is to place the file in the shared folder and that’s it. The Clerk can access your file and print it from his/her own computer. Amazing it is, but here lies a very huge and disturbing threat.

It was said that a file was placed in the shared folder and thus it also appeared in the Clerk’s computer thus he/she was able to print it, but what about the other users of the computer in the Internet Café?

Yes, of course your files can also be seen in their own computers! Too disturbing and truth is probably there are more security threats that expose us from the usage of this time-sharing environment setting. 

1. There is no file safe from being copied, edited, duplicated and deleted and the use of certain hardware like printer whether authorized or unauthorized.

• Other users are able to do this since mostly time-sharing environment setting do not need verification or authorization in what to do about the files that has been shared by other users.

2. The computer resources are not properly utilized and might even end up in “deadlock” mode.

• “Deadlock” is defined as a moment in time sharing environments when two or more users are having resources and are just waiting for each other, in this case neither users would be able to make progress in their program, no matter how many time slots they were allocated.

 

Faronics Deep Freeze Logo

Why can we say that dedicated machines are much more secure than time-sharing ones? Yes, it is true that there are programs designed to protect those who are only temporarily using the computers the Faronic’s Deep Freeze tool, a program specifically designed to erase or much more to reset the disks back to its original state thus deleting the files that were temporarily placed in the computer by means of rebooting. A very important tool indeed not only does it erase unwanted left-outs of your personal data but also deletes viruses that may have infected your computer while the Deep Freeze is still enabled, BUT when a computer is subjected to a time-sharing environment this kind of security tool becomes useless because the moment a file is shared there is no stopping who may be able to look, edit, copy and delete the said information/data because the tool requires a reboot and I believe it takes only a matter of second for those unauthorized users to alter with your data. I also strongly believe that the people who are only to edit or alter your data are those authorized by yourself thus a dedicated machine does the job in securing your files to yourself with out being copied by others, you can also assure that the means of copying your data can only be done by a portable storage device or at your exact workplace.

Well the best way to secure data is to narrow-down the ways in how others may be able access your file, in this circumstances choosing a dedicated machine is the best choice.