Operating System Assignment Example | Topics and Well Written Essays - 750 words

Operating System - Assignment Example Thirdly, it ensures that there is as little as possible the amount of damage that errant programs are likely to cause. Therefore, the protection mechanisms are either tools or procedures for the enforcement of the security policies while protection policies encompass what is allowed and those that are prohibited, while using a computer system (Whitman & Mattord, 2009). An access matrix is a protection security model which contains columns representing varied system resources; and the rows representing varied protection domains. Implementation is executed with reference to: domain, objects and rights entries. The model uses a lock-key mechanism where each resource is linked to a unique lock (bit patterns). Each domain has a specific bit pattern known as a key. Access is only granted if a domain key fits a resource lock. Moreover, modification of its own keys is not allowed. Every column of the table is kept as an access right for the specific object in order to discard blank entries. Every row is maintained as a list of a domains capability (Whitman & Mattord, 2009). The capabilities lists cannot be directly accessed by any user or by the domain because they are protected using a tag and an address space which can further be segmented. Based on Whitman & Mattord (2009) a computer virus is a program-code that attaches itself to an application so as operate concurrently while the application is running. A worm is a program that replicates itself in order to consume the host’s genetic code and mechanism. A virus attaches itself to a particular file or an opened program while a worm exploits the weakness an operating system or an application in order to duplicate itself. A virus relies on user(s) so as to spread the infected programs or files to other computer devices while a worm uses networks to duplicate itself to other computer devices without the help of user interventions. A virus can modify, delete or change the