How Does Vpn Work; Ike: Managing And Exchanging Keys - NETGEAR FVM318 Reference Manual

Reference Manual for the Model FVM318 Cable/DSL ProSafe Wireless VPN Security Firewall

How Does VPN Work?

A VPN can be thought of as a secure tunnel passing through the Internet, connecting two devices
such as a PC or router, which form the two tunnel endpoints. At one endpoint, data is encapsulated
and encrypted, then transmitted through the Internet. At the far endpoint, the data is received,
unencapsulated and decrypted. Although the data may pass through several Internet routers
between the endpoints, the encapsulation and encryption forms a virtual "tunnel" for the data.
DATA PACKET
Figure 8-6: VPN overview
The tunnel endpoint device, which encodes or decodes the data, can either be a PC running VPN
client software or a VPN-enabled router or server. Several software standards exist for VPN data
encapsulation and encryption, such as PPTP and IPSec. Your FVM318 firewall uses both PPTP
and IPSec.
To set up a VPN connection, you must configure each endpoint with specific identification and
connection information describing the other endpoint. This set of configuration information
defines a security association (SA) between the two points.

IKE: Managing and Exchanging Keys

IKE (Internet Key Exchange protocol) is the protocol used to perform key exchange between
IPSec devices. In order to initiate communication, the following tasks need to be done:
• Negotiate security protocols, encryption algorithms and keys with all communicating peers
Network, Routing, Firewall, and Wireless Basics
ENCRYPTION AND ENCAPSULATION
INTERNET
TRANSMISSION
VIA INTERNET
UNENCAPSULATION AND DECRYPTION
DATA PACKET
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