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Mohamed G. Gouda					CS 356
Spring 2018						Exercise 2
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Consider a network that consists of one client host x, one 
(corresponding) server host y, and one router r. Router r is
connected only to x (via subnetwork u) and to y (via another
subnetwork v). What are the protocol layers in x, the protocol 
layers in y, and the protocol layers in r.

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Solution:
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The protocol layers in x are:
application.x, transport.x, network.x, and link.x

The protocol layers in y are:
application.y, transport.y, network.y, and link.y

The protocol layers in r are:
network.r, link.u, and link.v