In a multiprogramming and time-sharing environment, several users share the system simultaneously. This situation can result in various security problems. a) What are two such problems?
1. One user can read the private data of another user - privacy.
2. One user can corrupt the private data of another user - integrity.
3. One user can prevent another user from getting anything done - denail of service.
b) Can we ensure the same degree of security in a time-shared machine as we have in a dedicated machine? Explain your answer.
There are two answers, either one correct.
a. Yes - if we can ensure that the operating system prevents any sharing of data between users, either for reading or writing, and fairly shares the computer, then we can achieve the same level of security.
b. No - we can never be sure that our software doesn't have bugs, so we can never be sure that we prevent all sharing of data and fairly allocate computer resources.

Which of the following is an example of intellectual properly! oa. new version of a novelb. journal of ideasc. pages of a bookood. lines of a poem

File account.java (see previous exercise) contains a definition for a simple bank account class with methods to withdraw, deposit, get the balance and account number, and return a string representation. note that the constructor for this class creates a random account number. save this class to your directory and study it to see how it works. then write the following additional code: 1. suppose the bank wants to keep track of how many accounts exist. a. declare a private static integer variable numaccounts to hold this value. like all instance and static variables, it will be initialized (to 0, since it’s an int) automatically. b. add code to the constructor to increment this variable every time an account is created. c. add a static method getnumaccounts that returns the total number of accounts. think about why this method should be static - its information is not related to any particular account. d. file testaccounts1.java contains a simple program that creates the specified number of bank accounts then uses the getnumaccounts method to find how many accounts were created. save it to your directory, then use it to test your modified account class.

Whose task it is to ensure that the product flows logically from one step to another?