Computer Science Homework Help

10. If two users share access to a segment, they must do so by the same name. Must their protection rights to it be the same? Why or why not?

11. A problem with either segmented or paged address translation is timing. Suppose a user wants to read some data from an input device into memory. For efficiency during data transfer, often the actual memory address at which the data are to be placed is provided to an I/O device. The real address is passed so that time- consuming address translation does not have to be performed during a very fast data transfer. What security problems does this approach bring?

18. Explain why asynchronous I/O activity is a problem with many memory protection schemes, including base/bounds and paging. Suggest a solution to the problem.