ZyXEL Communications NBG420N Manual Do Utilizador

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NBG420N User’s Guide
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 15 
IPSec VPN
15.1  IPSec VPN Overview
A virtual private network (VPN) provides secure communications between sites without the 
expense of leased site-to-site lines. A secure VPN is a combination of tunneling, encryption, 
authentication, access control and auditing. It is used to transport traffic over the Internet or 
any insecure network that uses TCP/IP for communication.
Internet Protocol Security (IPSec) is a standards-based VPN that offers flexible solutions for 
secure data communications across a public network like the Internet. IPSec is built around a 
number of standardized cryptographic techniques to provide confidentiality, data integrity and 
authentication at the IP layer.
The following figure provides one perspective of a VPN tunnel.
Figure 102   IPSec VPN: Overview
The VPN tunnel connects the NBG420N (X) and the remote IPSec router (Y). These routers 
then connect the local network (A) and remote network (B).
15.1.1  What You Can Do in the IPSec VPN Screens
Use the General Screen (
) to display and manage the NBG420N’s 
VPN rules (tunnels).
Use the SA Monitor Screen (
) to display and manage active VPN 
connections.