Setting up a authenication server like thing

i am really bad and no little to nothing about connection to internet with vb

but i have always wanted to know how to add like a auth before using a program.


basicly how it would work is you would enter a code into the program it would connect to the server and verify that its correct then allow the program to be ran.

my problem is that i dont know how to make the server or sending the packet to the server to be verifyed.

i thought of a simpler way is that you have a text file loaded to a ftp and if contents of the file = code then its allows you to connect.

if i can get help on the server thing the if possible i would like it to log ips so i can block them if they are are not allowed with in program.

just a thought i had

if some one could help me with this code i would be over joyed and would learn alot from this.


much thanks :)


PS

this is a side project security really isnt a big thing for me

its more a learning experiance

PS PS

im using vb 2012 express