ZyXEL Communications P-334 - Manual (Page 179)

Prestige 334 User’s Guide
Chapter 15 VPN Screens 178
15.15 Viewing SA Monitor
In the web configurator, click VPN and the SA Monitor tab. 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 labels in this tab.
Encryption Algorithm Select DES or 3DES from the drop-down list box. The Prestige's encryption
algorithm should be identical to the secure remote gateway. 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. 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.
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.
Encryption 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 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 Prestige.
Reset Click Reset to begin configuring this screen afresh.
Table 53 Rule Setup: Manual
LABEL DESCRIPTION
Note: When there is outbound traffic but no inbound traffic, the
SA times out automatically after two minutes. A tunnel with no
outbound or inbound traffic is "idle" and does not timeout until
the SA lifetime period expires.See
the Keep Alive section to
have the Prestige renegotiate an IPSec SA when the SA
lifetime expires, even if there is no traffic.