User`s manual

MICHELANGELO SHDSL VPN Firewall Bridge/Router
Chapter 4: Configuration
74
change encryption keys during the second phase of VPN negotiation. This function will provide better security,
but extends the VPN negotiation time. Diffie-Hellman is a public-key cryptography protocol that allows two
parties to establish a shared secret over an unsecured communication channel (i.e. over the Internet). There
are three modes, MODP 768-bit, MODP 1024-bit and MODP 1536-bit. MODP stands for Modular
Exponentiation Groups.
Pre-shared Key: This is for the Internet Key Exchange (IKE) protocol, a string from 4 to 128 characters. Both
sides should use the same key. IKE is used to establish a shared security policy and authenticated keys for
services (such as IPSec) that require a key. Before any IPSec traffic can be passed, each router must be able
to verify the identity of its peer. This can be done by manually entering the pre-shared key into both sides
(router or hosts).
Select the Apply button to apply your changes.