ZyXEL Communications Centralized Network Management Vantage CNM, Руководство пользователя

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Chapter 6 Device Security Settings
Vantage CNM User’s Guide
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6.3.3 VPN Rules (IKE) > Network Policy Add/Edit
In the VPN Rule (IKE) screen, click the Add icon from a gateway policy or click Edit from
an existing network policy to display the Network Policy screen.
Password Enter the corresponding password for the above user name. The password
can be up to 31 case-sensitive ASCII characters, but spaces are not allowed.
IKE Proposal
Negotiation Mode Select Main or Aggressive from the drop-down list box. Multiple SAs
connecting through a secure gateway must have the same negotiation mode.
Encryption Algorithm Select DES , 3DES or AES 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 .
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.
SA Life Time
(Seconds) Define the length of time before an IKE SA automatically renegotiates in this
field. It may range from 180 to 3,000,000 seconds (almost 35 days).
A short SA Life Time increases security by forcing the two VPN gateways to
update the encryption and authentication keys. However, every time the VPN
tunnel renegotiates, all users accessing remote resources are temporarily
disconnected.
Key Group You must choose a key group for phase 1 IKE setup. DH1 (default) refers to
Diffie-Hellman Group 1 a 768 bit random number. DH2 refers to Diffie-
Hellman Group 2 a 1024 bit (1Kb) random number.
Enable Multiple
Proposals Select this check box to allow the device to use any of its phase 1 or phase 2
encryption and authentication algorithms when negotiating an IPSec SA.
When you enable multiple proposals, the device allows the remote IPSec
router to select which encryption and authentication algorithms to use for the
VPN tunnel, even if they are less secure than the ones you configure for the
VPN rule.
Clear this check box to have the device use only the phase 1 or phase 2
encryption and authentication algorithms configured below when negotiating
an IPSec SA.
Apply Click Apply to save your changes back to the device.
Cancel Click Cancel to exit this screen without saving.
Table 48 Device Operation > Device Configuration > Security > VPN > VPN Rules (IKE) >
Gateway Policy Add/Edit
LABEL DESCRIPTION