beautypg.com

7 vpn global setting – ZyXEL Communications Centralized Network Management Vantage CNM User Manual

Page 138

background image

Chapter 6 Device Security Settings

Vantage CNM User’s Guide

138

6.3.7 VPN Global Setting

Select a device, click Device Operation > Device Configuration > Security > VPN >
Global Setting tab to open the screen shown next. Use this screen to change your device’s
global settings.

Encryption Algorithm

Select DES, 3DES or NULL from the drop-down list box.
When you use DES or 3DES, both sender and receiver must know the
Encryption Key, which can be used to encrypt and decrypt the
messages. 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.
Select NULL to set up a tunnel without encryption. When you select
NULL, you do not enter an encryption key.

Authentication Algorithm

When you use SHA1 or MD5, both sender and receiver must know the
Authentication Key, which can be used to generate and verify a
message authentication code. 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.

Encryption Key

This field only applies when you select ESP. With DES, type a unique
key 8 ASCII characters long. With 3DES, type a unique key 24 ASCII
characters long. Any characters may be used, including spaces, but
trailing spaces are truncated.

Authentication Key

Type a unique authentication key to be used by IPSec if applicable.
Enter 16 characters for MD5 authentication or 20 characters for SHA-
1
authentication. Any characters may be used, including spaces, but
trailing spaces are truncated.

Apply

Click Apply to save your changes back to the device.

Cancel

Click Cancel to begin configuring this screen afresh.

Table 52 Device Operation > Device Configuration > Security > VPN > VPN Rules (Manual)

> Add/Edit (continued)

LABEL

DESCRIPTION