James F. Kurose, Keith W. Ross

Problems

Computer Networks And The Internet

6

9780132856201

9

Consider
the discussion in Section 1.3 of packet switching versus circuit
switching in which an example is provided with a 1 Mbps link. Users
are generating data at a rate of 100 kbps when busy, but are busy
generating data only with probability *p
*=
0.1. Suppose that the 1 Mbps link is replaced by a 1 Gbps link.

a.
What is *N,
*the
maximum number of users that can be supported simultaneously under
circuit switching?

b.
Now consider packet switching and a user population of *M
*users.
Give a formula (in terms of *p*,
*M*,
*N*)
for the probability that more than *N
*users
are sending data.

a)

**Number of users (N)=**

So, the maximum number of users that can be supported simultaneously under circuit switching=1000 users

b)

Consider packet switching and a user population of *M *users.

**Formula (in terms of p, M,N) for the probability that more than N users are sending data=**