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Keep Your Files Secure

In these days secure ways of keeping private files in Operating Systems/computers are vivid.People can even store Files in a virtual network.But in the case of standalone computers,keeping files safe is only by softwares,which provide password locking function(winrar or winzip).Even then programs like blockhunter3,xazmick,spanishdildo.exe,passcrack.exe etc can take control of those Files by cracking Operating Systems and applications.After that ,programs like speakup,ventura,masskill,bforce.exe,demonstar,can crack your passwords.Because they follows the bruteforce attack.

Programs like winrar or winzip,not only compresses the files,it gives a password too.But softwares like winrarpasscrack etc can crack those passwords.Cracking and Hacking is a unique way of collecting something without owner's permission.

Major errors in Operating Systems allowing these attacks to carry forward their desired datas.To block these errors we need to know something about the Operating Systems, we are working.It is not basic in any means.It cost much.

Ok.Just for a formal start i am writing a thing about
The basic functions of an operating system.
In technical and systematical way ,i must tell you,
Operating system
controls,shares,activates,allows and connects the hardware among various
applications
for various uses. Operating system acts as resource allocator and manager.There are many conflicts and unauthorized requests in a computer for resources .The operating system must then decide which requests are allocated resources to operating the computer efficiently and fairly. Also Operating System is a control program, which controls the user to prevent errors and improper use of the computer.

So that was just a basic.From these we know Operating System is the one,which creates and controls.

An operating System is running in a physical memory(Known as *RAM).Even then OS(Operating System) uses Virtual memory.Virtual memory is hardware technique where the system appears to have more memory that it actually does. This is done by time-sharing, the physical memory and storage parts of the memory are one disk when they are not actively being used.

To go a little bit further,i must tell you about multitasking, multiprogramming, and multithreading.
Those are certain processes in an OS.Multiprogramming is the technique of running several programs at a time using timesharing. It allows a computer to do several things at the same time.The concept of multiprogramming is that the operating system keeps several jobs in memory simultaneously.With this one,your *CPU never gets idle.Multitasking is the logical extension of multiprogramming .Multitasking is quite similar to multiprogramming but difference is that the switching between processes occurs so frequently that the users can interact with each program while it is running.Multithreading is a bit complicated ,A program typically is implemented as a separate process with several threads of control.To tell you in simple way, In some situations a single application may required to perform several tasks ,for example a web server,it accepts client requests for web pages, images, sound, and so forth. A busy web server may have many clients concurrently accessing it. If the web server ran as a traditional single-threaded process, it would be able to service only one client at a time. The amount of time that a client might have to wait for its request to be serviced could be enormous. So it is efficient to have one process that contains multiple threads to serve the same purpose. This approach would multithread the web-server process, the server would create a separate thread that would listen for client requests when a request was made rather than creating another process it would create another thread to service the request.

Ok that was it.Those are three major processes in a computer.By engaging these processes in a bad way,crackers can access the system.They can take your valuable datas from your *hard disk.Even then crackers can take datas from your cache memory.Cache memory is random access memory (RAM) that a computer microprocessor can access more quickly than it can access regular RAM. As the microprocessor processes data, it looks first in the cache memory ,and it does not have to do the more time-consuming on reading data from larger memory.So if you are selling your computer without your hard disk,have a chance of data lose.Beware of that.

An OS itself Knows the Safe State and the deadlock avoidance.When a program requests an available resource, OS must decide if an immediate allocation leaves the system in a safe state. System is in safe state if there exists a safe sequence of all processes. Deadlock Avoidance, ensure that a system will never enter an unsafe state.


These are those several facts defies a computer into a *complete system.Just making a change in these functions,these cracks enters.We can prevent them to take our datas,by knowing these little facts and working on it.Hope you are happy.Please comment for making it rich more up to you.