Suppose users share a 1 mbps link. also suppose each user
requires100
kbps when transmitting, but each user transmits only 10 percent
ofthe time.
(see the discussion packet switching versus circuit switching
insection 1.3).
a. when circuit switching is used, how many users can
besupported?
b. for the remainder of this problem, suppose packetswitching is
used.
find the probability that a given user is transmitting.
c. (suppose that there are 50 users. find the probability that
atany given
time exactly n users are transmitting simultaneously (hint: use
thebinomial
distribution).
d. find the probability that there are 11 or more
userstransmitting
simultaneously. (hint: use the central limit theorem.)
e. solve d for 20 or more users.