Virtual Private Network using JAVA, J2EE

Introduction
A virtual private network (VPN) is a private data network that makes use of the public telecommunication infrastructure, maintaining privacy through the use of a tunneling protocol and security procedures. The idea of the VPN is to give the company the same capabilities at much lower cost by using the shared public infrastructure rather than a private one.
A well-designed VPN can provide great benefits for an organization. It can:
· Extend geographic connectivity.
· Improve security where data lines have not been ciphered.
· Reduce operational costs versus traditional WAN.
· Reduce transit time and transportation costs for remote users.
· Simplify network topology in certain scenarios.
· Provide global networking opportunities.
· Provide telecommuter support.
· Provide broadband networking compatibility.
· Provide faster ROI (return on investment) than traditional carrier leased/owned WAN lines.
· Show a good economy of scale.
· Scale well, when used with a public key infrastructure.
Tunneling

Tunneling is the transmission of data through a public network in such a way that routing nodes in the public network are unaware that the transmission is part of a private network. Tunneling is generally done by encapsulating the private network data and ....