Compare the update semantics of UNIX when accessing local files with those of NFS and AFS.
Under what circumstances might clients become aware of the differences?
What will be an ideal response?
UNIX:strict one-copy update semantics;
NFS:approximation to one-copy update semantics with a delay (~3 seconds) in achieving consistency;
AFS:consistency is achieved only on close. Thus concurrent updates at different clients will result in lost
updates – the last client to close the file wins.
See the solution to Exercise 8.1for a scenario in which the difference between NFS and UNIX update
semantics would matter. The difference between AFS and UNIX is much more visible. Lost updates will occur
whenever two processes at different clients have a file open for writing concurrently.
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The program that is used to create and modify VBA code is called the ____________________.
Fill in the blank(s) with the appropriate word(s).
When you set up a virtual directory, you give it an alias, which is a name to identify it to a Web browser.
Answer the following statement true (T) or false (F)
Why are Layer 2 addresses not needed in point-to-point topologies?
What will be an ideal response?
A Trojan horse is a program that hides itself by deleting a system file and taking on the system file's name.
True