VPN
A virtual private network (VPN) is a private
network that interconnects remote (and often geographically separate) networks
through primarily public communication infrastructures such as the Internet.
VPNs provide security through tunneling protocols and security procedures such
as encryption. For example, a VPN could be used to securely connect the branch
offices of an organization to a head office network through the public
Internet. A VPN can also be used to interconnect two similar-type networks over
a dissimilar middle network for example, two IPv6 networks over an IPv4 network.
There are 2 types of VPNS, which are
·
Site-to-Site VPN
·
Remote Access VPN
Site-to-Site
A site-to-site
VPN allows offices in multiple fixed locations to establish secure
connections with each other over a public network such as the Internet.
Site-to-site VPN extends the company's network, making computer resources from
one location available to employees at other locations. An example of a company
that needs a site-to-site VPN is a growing corporation with dozens of branch
offices around the world.
Remote Access
A remote-access
VPN allows individual users to establish secure connections with a remote
computer network. Those users can access the secure resources on that network
as if they were directly plugged in to the network's servers. An example of a
company that needs a remote-access VPN is a large firm with hundreds of
salespeople in the field. Another name for this type of VPN isvirtual
private dial-up network (VPDN), acknowledging that in its
earliest form, a remote-access VPN required dialing in to a server using an
analog telephone system.
References
http://computer.howstuffworks.com/vpn3.htm
