Data Confidentiality; Data Integrity; Data Origin Authentication; Vpn Applications - ZyXEL Communications 802.11g ADSL 2+ 4-Port Security Gateway HW-D Series User Manual

P-662H/HW-D Series User's Guide

Figure 125 Encryption and Decryption

15.1.3.2 Data Confidentiality

The IPSec sender can encrypt packets before transmitting them across a network.

15.1.3.3 Data Integrity

The IPSec receiver can validate packets sent by the IPSec sender to ensure that the data has not
been altered during transmission.

15.1.3.4 Data Origin Authentication

The IPSec receiver can verify the source of IPSec packets. This service depends on the data
integrity service.

15.1.4 VPN Applications

The ZyXEL Device supports the following VPN applications.
• Linking Two or More Private Networks Together
Connect branch offices and business partners over the Internet with significant cost
savings and improved performance when compared to leased lines between sites.
• Accessing Network Resources When NAT Is Enabled
When NAT is enabled, remote users are not able to access hosts on the LAN unless the
host is designated a public LAN server for that specific protocol. Since the VPN tunnel
terminates inside the LAN, remote users will be able to access all computers that use
private IP addresses on the LAN.
• Unsupported IP Applications
A VPN tunnel may be created to add support for unsupported emerging IP applications.
See the chapter on Getting to Know Your ZyXEL Device for an example of a VPN
application.
234 Chapter 15 Introduction to IPSec