Building Vpn - How and where to start

I want to code a simpe vpn as a part of my course work. I a开发者_Python百科m looking for ways to start. Will be helpful if you guys could help me with resources

As a basic starting point, you need to be able to write a client/server setup in your language of choice that will transport over IP. Your VPN must also be able to present the operating system with a network interface. If you are using Linux, I suggest the tun/tap system interface. For reference, you could look at the code in qemu which does make use of those OS calls. For the encryption purposes, the OpenSSL library should be able to provide you with all the calls necessary.

I'm not sure what the ultimate requirements of your coursework are. You can build anything from a basic shared-symmetric key setup that can be quickly hacked up to the bottomless pit of trying to build a production worthy VPN system. You should mention your requirements.