-------------------------------------------------------------------------
Mohamed G. Gouda					CS 356
Spring 2017						Exercise 2
-------------------------------------------------------------------------

Consider two client-server applications that are running on top of the
UDP Transport Layer. The first application consists of one server s1 
(that is hosted in host sh1) and one client c (that is hosted in host 
ch). The second application consists of one server s2 (that is hosted 
in sh2) and client c (that is hosted in ch). 

(a) How many ports are allocated in these two applications?
(b) How many sockets are allocated in these two applications?

-------------------------------------------------------------------------
Solution:
-------------------------------------------------------------------------

(a) These two applications allocate 4 ports: s1 allocates 1 well-known 
low-numbered port i1, s2 allocates 1 well-known low-numbered port i2, and
c allocates 2 arbitrary high-numbered ports j1 and j2.

(b) These two applications allocate 4 sockets: one socket is bound to each
of the 4 ports allocated by the applications.