ZyXEL nbg-5715 Guia Do Utilizador

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NBG5715 User’s Guide
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IPSec VPN
18.1  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 75   
IPSec VPN: Overview
The VPN tunnel connects the NBG5715 (X) and the remote IPSec router (Y). These routers then 
connect the local network (A) and remote network (B).
18.2  What You Can Do in this Chapter
• Use  the  General screen to display and manage the NBG5715’s VPN rules (tunnels) (
).
• Use  the  SA Monitor screen to display and manage active VPN connections (
VPN Tunnel
X
Y