CIS 331: Network Introduction
Lehman College, City University of New York
Fall 2013
This Homework Is Due By 11:59 PM on September 22, 2013
Given the following IP addresses (In Hexadecimal), identify (a) the Class, (b) the Network
ID, (c) the Host ID of the following IP Addresses, and (d) write each address in dotted
decimal notation:
7648BFDC
D79CAB9D
9A7859E3
C7694F3E
09427EFA
8A7D3C42
594DC3BE
D1792EC3
A6532FDC
Exactly how many class A, B, and C networks can exist? Exactly how many hosts can a
network in each class have? How many possible addresses are possible in each class?
Be careful to allow for broadcast as well as class D and E addresses.
How many IP addresses would be needed to assign a unique IP address to every house in
the USA? The world? Is the IP address space sufficient? (Search the internet for reasonable
numbers of households in the USA and the world).
One common algorithm for managing the ARP cache replaces the least recently used entry
when adding a new one. Under what circumstances can this algorithm produce unnecessary
network traffic?
Suppose machine C receives an ARP request sent from A looking for target B, and suppose
C has the binding for IPB to HWB in its ARP cache. Should C answer the request? Explain.
Please submit the completed assignment on Blackboard as a Microsoft Word file or a PDF file.
No other forms of submission will be accepted.