TMS zl Management and Configuration Guide ST.1.1.100430

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Overview

Virtual Private Network (VPN)

The TMS zl Module can act as a VPN gateway. You should use the VPN

functionality when you want to protect traffic from eavesdropping and from

tampering. Typically, such protection is necessary when the traffic passes

through an untrusted network such as the Internet or a wireless network that

does not offer encryption.

You can also create VPNs inside your private network to protect sensitive

information from all but authorized users.

VPN Protocols

The TMS zl Module supports these protocols:

■ IP security (IPsec):

• With Internet Key Exchange (IKE) version 1

• With manual keying

■ Layer 2 Tunneling Protocol (L2TP) over IPsec

■ Generic Routing Encapsulation (GRE) with or without IPsec

IPsec

IPsec secures and encapsulates IP packets with one or both of these two

protocols:

■ Authentication Header (AH)—provides data integrity and optional

encryption

■ Encapsulation Security Payload (ESP)—provides encryption and

optional data integrity

IKE helps the two endpoints of an IPsec VPN tunnel (also called an IPsec

security association [SA]) to negotiate the keys for data integrity and encryp-

tion. IKE is the preferred option, but the TMS zl Module also supports manual

keying.