MD5: A one-way hashing algorithm that produces a 128−bit hash.

Billion BIPAC-7500G–802.11g ADSL VPN Firewall Router with 3DES Accelerator

not tampered with in transmit. There are three options, Message Digest 5 (MD5), Secure Hash Algorithm (SHA-1) or NONE. SHA-1 is more resistant to brute-force attacks than MD5, however it is slower.

MD5: A one-way hashing algorithm that produces a 128−bit hash.

SHA-1: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 NONE. NONE 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).

Select the Save button to save the setting.

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Chapter 4: Configuration

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Billion Electric Company BIPAC-7500G user manual MD5 A one-way hashing algorithm that produces a 128−bit hash