ZyXEL Communications Prestige 652H series, Руководство пользователя

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Prestige 652H/HW Series User’s Guide
16-26 VPN Screens
Table 16-9 VPN Manual Setup
LABEL DESCRIPTION
IPSec Protocol Select ESP if you want to use ESP (Encapsulation Security Payload). The ESP
protocol (RFC 2406) provides encryption as well as some of the services offered by
AH . If you select ESP here, you must select options from the Encryption
Algorithm and Authentication Algorithm fields (described next).
Encryption Algorithm Select DES , 3DES or NULL from the drop-down list box.
When DES is used for data communications, both sender and receiver must know
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. Select NULL to set
up a tunnel without encryption. When you select NULL , you do not enter an
encryption key.
Encapsulation Key
(only with ESP)
With DES , type a unique key 8 characters long. With 3DES , type a unique key 24
characters long. Any characters may be used, including spaces, but trailing spaces
are truncated.
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.
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.
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 remove the current rule.
16.15 Viewing SA Monitor
Click VPN and Monitor to open the SA Monitor screen as shown. Use this screen to display and manage
active VPN connections.
A Security Association (SA) is the group of security settings related to a specific VPN tunnel. This screen
displays active VPN connections. Use
Refresh to display active VPN connections. This screen is read-only.
The following table describes the fields in this tab.