Ike Phases - ZyXEL Communications Prestige 662H Series User Manual

Prestige 662H/HW Series User's Guide
Table 72 VPN IKE (continued)
LABEL
Pre-Shared Key
Encryption
Algorithm
Authentication
Algorithm
Advanced
Back
Apply
Cancel
Delete

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.
231
DESCRIPTION
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.
Select DES, 3DES, AES 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.
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.
Click Advanced to configure more detailed settings of your IKE key management.
Click Back to return to the previous screen.
Click Apply to save your changes back to the Prestige.
Click Cancel to begin configuring this screen afresh.
Click Delete to delete the current rule.
Chapter 19 VPN Screens