Hardare Lock Through Parallel Port For Client-Server Access

[Princy Rohit]

Hello!
This is my first post.
Well,am fairly new to linux and its applications

Presently,I've been assigned a project on Linux(Fedora 6)

The steps of the project are as follows:

Step 1:
Prepare a hardware lock using microcontroller 8051.
The PC's Parallel Port has to read the password,
compare it with the program password and if same should
run the C code else reject and refuse to open the
program----SUCCESSFULLY COMPLETED!!!

Step 2:
While the C code is running, simultaneously a C code should
run on the background every few seconds to check if the hardware
lock is still connected and the password has not been changed.
If either of the two happens,then the running program should
be abruptly stopped.----NOT YET ABLE TO FIND OUT THE SOLUTION!!!

Step 3:
Now one more condition is that,the hardware lock is to be
connected to the server only. The other systems in the LAN
should request access to the server,assuming the harware
is connected and password is correct,the C code thats is to
be executed should be tansferred to the client and the execution
should be carried out,but once the hardware has been either removed
or password has been changed,excution on the client should be abruptly
disabled.There is another catch to this,i.e.,only 15 clients at
a time can access the server at a time,any other requests
should be rejected by the server!----NO CLUE AS TO HOW TO EVEN START
THIS STEP!!!NO IDEA ABOUT TRANSFERRING AN EXECUTABLE FILE TO THE CLIENT
SIDE AND EXECUTING IT!!!CLIENT SERVER!!!

KINDLY REQUEST YOUR HELP!ANY MATERIAL TO READ, OR PSEUDO CODES
WOULD BE GREAT HELP..........
AS OF NOW AM TOTALLY CLUELESS AS TO HOW TO PROCEED.........

[Salem]

Step 2 - read up on timers or threads.

Step 0
http://www.catb.org/~esr/faqs/smart-questions.html#writewell
Drop the excessive CAPS and punctuation.

[wildgoose]

Easy. You have a typicall Server-client situation.

I normally work with Windows not Linux but you have a server that runs a Watchdog application. It establishes the verification, tracks number of authorized connections. Client applications connect to it, it does the authentication up to the threshold set and establishes the connection. It doubles both as a a gateway and as the authentication system.

A Beaver thread maintains the host connection and the heartbeat status inquiries. Due to hacking, etc. The mainline thread and the beaver threads need to do communications so as if the Beaver thread gets hacked or simulated that the application won't just shutdown, it'll slowly disintegrate. (Makes it harder to hack why it fails!) You can also pass down a decryption key to decode sections of the application. Without the connection, the application can't decode the data thus becomes useless! These are just some of the methods available to you!

[Princy Rohit]

Thank you sir for your response. Will do as adviced and 'll update you on the developments.