ZyXEL Communications NBG420N Manual Do Utilizador

 Chapter 15 IPSec VPN

NBG420N User’s Guide

Click the Advanced... button in the Rule Setup screen to open this screen.
Use this screen to configure a VPN rule.

Pre-Shared Key

Type your pre-shared key in this field. A pre-shared key identifies a 

communicating party during a phase 1 IKE negotiation. It is called "pre-shared" 

because you have to share it with another party before you can communicate 

with them over a secure connection. 
Type from 8 to 31 case-sensitive ASCII characters or from 16 to 62 hexadecimal 

("0-9", "A-F") characters. You must precede a hexadecimal key with a "0x” (zero 

x), which is not counted as part of the 16 to 62 character range for the key. For 

example, in "0x0123456789ABCDEF", “0x” denotes that the key is hexadecimal 

and “0123456789ABCDEF” is the key itself.
Both ends of the VPN tunnel must use the same pre-shared key. You will receive 

a “PYLD_MALFORMED” (payload malformed) packet if the same pre-shared key 

is not used on both ends.

Encryption 

Algorithm

Select which key size and encryption algorithm to use for data communications. 

Choices are:
DES - a 56-bit key with the DES encryption algorithm
3DES - a 168-bit key with the DES encryption algorithm
The NBG420N and the remote IPSec router must use the same algorithms and 

key , which can be used to encrypt and decrypt the message or to generate and 

verify a message authentication code. Longer keys require more processing 

power, resulting in increased latency and decreased throughput.

Authentication 

Algorithm

Select which hash algorithm to use to authenticate packet data. Choices are 

SHA1 and MD5. SHA1 is generally considered stronger than MD5, but it is also 

slower.

Advanced...

Click Advanced... to configure more detailed settings of your IKE key 

management. 

Apply

Click Apply to save your changes back to the NBG420N.

Reset

Click Reset to begin configuring this screen afresh.

Cancel

Click Cancel to exit the screen without making any changes.

Table 63   SECURITY > VPN > Rule Setup: IKE (Basic)  (continued)