Upon completion you will be able to: Understand the difference between an internet and an extranet, understand private, hybrid, and virtual private networks, understand how VPN can guarantee privacy, understand the mechanism of NAT.

Used to connect two private networks together via the Internet Used to connect remote users to a private network via the Internet This could be done by opening your firewall to the LAN networking protocols (NETBIOS, NFS NetWare, AppleTalk)) But… it would also make those protocols available to any one on the Internet and they could come into your LAN at will Effectively make the whole Internet your LAN Exposes all of your data Anyone can easily take advantage of vulnerabilities in your internal hosts No privacy Better solution is to use a VPN in conjunction with your firewall ...

Virtual private networks (VPNs) are another feature that firewalls have quickly adopted. Firewalls, by the very nature of their placement in the network design, represent a natural device to provide termination for LAN-to-LAN and in some cases remote-access VPNs.