ZyXEL p-662h-61 Guia Do Utilizador

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Prestige 662HW Series User’s Guide
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Chapter 19 VPN Screens
19.11   IKE Phases
There are two phases to every IKE (Internet Key Exchange) negotiation – phase 1 
(Authentication) and phase 2 (Key Exchange). A phase 1 exchange establishes an IKE SA and 
the second one uses that SA to negotiate SAs for IPSec.
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 DES, 3DESAES or NULL from the drop-down list box. 
When you use one of these encryption algorithms for data communications, both 
the sending device and the receiving device must use the same secret key, which 
can be used to encrypt and decrypt the message or to generate and verify a 
message authentication code. The DES encryption algorithm uses a 56-bit key. 
Triple DES (3DES) is a variation on DES that uses a 168-bit key. As a result, 
3DES is more secure than DES. It also requires more processing power, resulting 
in increased latency and decreased throughput. This implementation of AES uses 
a 128-bit key. AES is faster than 3DES
Select NULL to set up a tunnel without encryption. When you select NULL, you 
do not enter an encryption key.
Authentication 
Algorithm
Select SHA1 or MD5 from the drop-down list box. MD5 (Message Digest 5) and 
SHA1 (Secure Hash Algorithm) are hash algorithms used to authenticate packet 
data. The SHA1 algorithm is generally considered stronger than MD5, but is 
slower. Select MD5 for minimal security and SHA-1 for maximum security. 
Advanced
Click Advanced to configure more detailed settings of your IKE key management. 
Back
Click Back to return to the previous screen.
Apply
Click Apply to save your changes back to the Prestige.
Cancel
Click Cancel to begin configuring this screen afresh.
Delete
Click Delete to delete the current rule.
Table 72   VPN IKE (continued)
LABEL
DESCRIPTION