Billion BiPAC 7404V(G)OX/V(G)PX User Manual page 133

SHA1: A one-way hashing algorithm that produces a 160−bit hash.
Encryption: Select the encryption method from the pull-down menu. There are four options, DES,
3DES, AES and NULL. NULL means it is a tunnel only with no encryption. 3DES and AES are
more powerful but increase latency.
DES: Stands for Data Encryption Standard, it uses 56 bits as an encryption method.
3DES: Stands for Triple Data Encryption Standard, it uses 168 (56*3) bits as an encryption
method.
AES: Stands for Advanced Encryption Standards, it uses 128 bits as an encryption method.
Perfect Forward Secrecy: Choose whether to enable PFS using Diffie-Hellman public-key
cryptography to 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).
Click Edit/Delete to save your changes.
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