Billion Electric Company 7500GL Manuale Utente

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myGuard 7500GL 802.11g Security ADSL Router 
 
Chapter 4:Configuration 
 
 
 
Authentication: 
Authentication establishes the integrity of the datagram and ensures it is 
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, DES3DESAES 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). 
 
 
 
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