TCP/IP Animation , VPN
VPNVPN (Virtual Private Network) is for remote secure access. It is mainly used between the different LAN of a corporation or between a corporation and its employees.There are some kinds of VPN.1. Internet VPNAt this VPN, after the data is encrypted by security protocol, it is sent through internet area. This way is much cheaper than IP-VPN.IPsec or SSL is used as security protocol for VPN. At IPsec, the data is encrypted with IPsec and added special header. At SSL, the data is encrypted with SSL. The explanation of SSL for VPN is left out here.2. IP-VPNIP-VPN uses the exclusive circuit ISP provides. The trait of this way is that high security is ensured and expensive to contract.MPLS header is added to the data packets at every communication.