README file for dhcpclient, a DHCP simulation program used to show how
the JDHCP API works. The simulation will interact with the DHCP server
on your network and attempt to act like a DHCP client. To find
out more about the lifecycle of a DHCP client, read RFC 2131. 


To compile dhcpclient.java.

First compile the JDHCP package (see ../README for more info on this)

You need the JDHCP package in your classpath. 

Do this by setting the CLASSPATH variable. In JDK1.1 your CLASSPATH variable 
shoudl be pointing to the classes.zip file that ships with JDK and the
current directory. 

In Unix: 

(tcsh) % setenv CLASSPATH <path-to-JDHCP-1.1.x>/jars/JDHCP.jar:$CLASSPATH
(bash) % set CLASSPATH=<path-to-JDHCP-1.1.x>/jars/JDHCP.jar:$CLASSPATH

In Windows 9x/NT:
% set CLASSPATH=<path-to-JDHCP-1.1.x>\JARS\JDHCP.jar:$CLASSPATH

In JDK1.2, there is no need to set the classpath, the javac -classpath 
parameter will do the correct thing. 


Compiling dhcpclient.java

(JDK1.1 w/ CLASSPATH set)% javac dhcpclient.java

or 

(JDK1.2) % javac -classpath <path-to-JDHCP-1.1.x>\JARS\JDHCP.jar:.

Running dhcpclient

(JDK1.1 w/ CLASSPATH SET) % java dhcpclient <ethernet_addresss> 

(JDK1.2) % java -classpath <path-to-JDHCP-1.1.x>\JARS\JDHCP.jar:. dhcpclient <ethernet_addresss> 

For example:

%java dhcpclient 12:34:56:76:0f:08

If everything works correctly, you will see this message (example only):

********************************************************
* Starting dhcpclient sample application written using *
* JDHCP v1.1.1. Learn more about the JDHCP project at  *
* http://www.eg.bucknell.edu/~jgoldsch/dhcp/           *
* JDHCP is an API for writting Java(tm) applications   *
* that speak the Dynamic Host Configuration Protocol   *
* Note: dhcpclient is merely a simulation of what a    *
* DHCP client does within its lifecycle as specified   *
* in RFC 2131 and 2132. This application and JDHCP was *
* co-authored by Jason Goldschmidt and Nick Stone.     *
********************************************************
Sending DHCPDISCOVER....
12:34:56:76:0f:08 received a DHCPOFFER for 192.168.88.9
12:34:56:76:0f:08 sending DHCPREQUEST for 192.168.88.9
12:34:56:76:0f:08 received an DHCPACK and a leasetime.
Binding to IP address: 192.168.88.9
Goodnight for 1800000 seconds
.
.


If instead you receive this message:
Socket Bind Error: 
Another process is bound to this port
or you do not have access to bind a process to this port

Then you do not have access to run dhcpclient on that machine. 


Send me <jgoldsch@acm.org> bugs, questions, patches and ideas!