Homework 2
CS43
5%, due Feb. 29
Use a word processor for the non-programming exercises.
- Write a program which translates an Internet domain name to its
registered IP address. The program should take the domain name as a
command line argument. The program should produce output like this:
abacus:~
% ./lookup www
Official name: keystone.westminster.edu
There are aliases:
www.westminster.edu
IP address(es):
204.171.15.203
abacus:~
% ./lookup westminster-gw.prepnet.com
Official name: westminster-gw.prepnet.com
IP address(es):
129.250.90.2
192.204.20.1
abacus:~
% ./lookup ftp.netscape.com
Official name: ftp20.netscape.com
There are aliases:
ftp.netscape.com
IP address(es):
205.218.156.36
Use gethostbyname(3) to perform the lookup. The layout of
struct hostent was discussed when the homework was handed-out. I will not
be repeating that information.
- Calculate the maximum number of class A, B, and C network IDs. Fetch
the file
nsfnet/statistics/history.netcount using anonymous FTP from
the host
nic.merit.edu. This file contains the number of domestic
and foreign networks announced to the NSFNET infrastructure. Plot these
values with the year on the x-axis and a logarithmic y-axis with the total
number of networks. The maximum value for the y-axis should the maximum
number of network IDs calculated previously. If the data shows a visual
trend, extrapolate the values to estimate when the current addressing
scheme will run out of network IDs.
- Obtain a copy of the Host Requirements RFC (RFC 1122) and look up the
robustness principle that applies to every layer of the TCP/IP
protocol suite. What is the reference for this principle? You will find
RFCs in keystone:/mnt/rfc.
Thomas P. Kelliher
Wed Feb 21 08:47:47 EST 1996
Tom Kelliher