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Mohamed G. Gouda					CS 356
Spring 2018						Exercise 3
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A client u sends a GET-page-x request when (1) the proxy server of
u has the pair (x', T'), where x' is the version of page x that is
last modified at time T', and when (2) the original server of x has
the pair (x", T"), where x" is the version of page x that is last
modified at time T".

What is the response that client u will receive later as a reply to
its request?

Explain your answer.

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Solution
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We need to consider two cases:

Case 1: (T' = T"): In this case, x' = x" and client u will receive
the page version x' or the page version x" (since they are the same).

Case 2: (T' < T"): In this case, client u will receive the page
version x".

Note that in each one of these two cases, client u will receive the
page version x".