Suppose that the operations of the BLOB object are separated into two categories – public operations that are available to all users and protected operations that are available only to certain named users. State all of the problems involved in ensuring that only the named users can use a protected operation. Supposing that access to a protected operation provides information that should not be revealed to all users, what further problems arise?

What will be an ideal response?

Each request to access a protected operation must include the identity of the user making the request. The problems are:
• defining the identities of the users. Using these identities in the list of users who are allowed to access the protected operations at the implementation of the BLOB object. And in the request messages.
• ensuring that the identity supplied comes from the user it purports to be and not some other user pretending to be that user.
• preventing other users from replaying or tampering with the request messages of legitimate users. Further problems.
• the information returned as the result of a protected operation must be hidden from unauthorised users.
This means that the messages containing the information must be encrypted in case they are intercepted by unauthorised users.

Computer Science & Information Technology

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Answer the following statement true (T) or false (F)

Computer Science & Information Technology

Write an rsync command that copies the backmeup directory from your home directory on the local system to the /tmp directory on guava, preserv- ing file ownership, permissions, and modification times. Write a command that will copy the same directory to your home directory on guava. Do not assume the working directory on the local system is your home directory.

What will be an ideal response?

Computer Science & Information Technology