Overview - ZyXEL Communications SBG5500-A User Manual

10.1 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.
10.2 What You Can Do in this Chapter
• Use the VPN Status screen to look at the VPN tunnels currently established in the SBG
page 162).
• Use the IPsec VPN screen to display and manage active IPsec VPN connections
page 163).
• Use the PPTP VPN screen to configure the PPTP VPN settings in the
• Use the L2TP VPN screen to configure the SBG's L2TP VPN
• Use the L2TP Client Status screen to view connection details for L2TP clients
185).
10.3 What You Need to Know
IPsec VPN
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.
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H A P T E R
(Section 10.5 on
SBG(Section 10.6 on page
settings(Section 10.7 on page
(Section 10.8 on page
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VPN
(Section 10.4 on
176).
179).