ZyXEL Communications USG40 User Manual page 545

Table 209 Configuration > VPN > IPSec VPN > VPN Connection > Add/Edit (continued)
LABEL DESCRIPTION
First DNS Server The Domain Name System (DNS) maps a domain name to an IP address and vice
(optional)
versa. The ZyWALL/USG uses these (in the order you specify here) to resolve domain
names for VPN. Enter a DNS server's IP address.
Second DNS Enter a secondary DNS server's IP address that is checked if the first one is
Server (Optional)
unavailable.
First WINS Server Type the IP address of the WINS (Windows Internet Naming Service) server that you
(Optional)
want to send to the DHCP clients. The WINS server keeps a mapping table of the
computer names on your network and the IP addresses that they are currently using.
Second WINS Enter a secondary WINS server's IP address that is checked if the first one is
Server (Optional)
unavailable.
Phase 2 Settings
SA Life Time Type the maximum number of seconds the IPSec SA can last. Shorter life times
provide better security. The ZyWALL/USG automatically negotiates a new IPSec SA
before the current one expires, if there are users who are accessing remote
resources.
Active Protocol Select which protocol you want to use in the IPSec SA. Choices are:
AH (RFC 2402) - provides integrity, authentication, sequence integrity (replay
resistance), and non-repudiation but not encryption. If you select AH, you must
select an Authentication algorithm.
ESP (RFC 2406) - provides encryption and the same services offered by AH, but its
authentication is weaker. If you select ESP, you must select an Encryption algorithm
and Authentication algorithm.
Both AH and ESP increase processing requirements and latency (delay).
The ZyWALL/USG and remote IPSec router must use the same active protocol.
Encapsulation Select which type of encapsulation the IPSec SA uses. Choices are
Tunnel - this mode encrypts the IP header information and the data.
Transport - this mode only encrypts the data.
The ZyWALL/USG and remote IPSec router must use the same encapsulation.
Proposal Use this section to manage the encryption algorithm and authentication algorithm
pairs the ZyWALL/USG accepts from the remote IPSec router for negotiating the
IPSec SA.
Add Click this to create a new entry.
Edit Select an entry and click this to be able to modify it.
Remove Select an entry and click this to delete it.
# This field is a sequential value, and it is not associated with a specific proposal. The
sequence of proposals should not affect performance significantly.
Chapter 29 IPSec VPN
ZyWALL/USG Series User's Guide
545