ZyWALL 5/35/70 Series User’s Guide
319 Chapter 19 VPN Screens
Server Mode Select Server Mode to have this ZyWALL authenticate extended authentication
clients that request this VPN connection.
You must also configure the extended authentication clients’ usernames and
passwords in the authentication server’s local user database or a RADIUS server
(see
Chapter 21 on page 366).
Click Local User to go to the Local User Database screen where you can view
and/or edit the list of user names and passwords. Click RADIUS to go to the
RADIUS screen where you can configure the ZyWALL to check an external
RADIUS server.
During authentication, if the ZyWALL (in server mode) does not find the extended
authentication clients’ user name in its internal user database and an external
RADIUS server has been enabled, it attempts to authenticate the client through
the RADIUS server.
Client Mode Select Client Mode to have your ZyWALL use a username and password when
initiating this VPN connection to the extended authentication server ZyWALL.
Only a VPN extended authentication client can initiate this VPN connection.
User Name Enter a user name for your ZyWALL to be authenticated by the VPN peer (in
server mode). The user name can be up to 31 case-sensitive ASCII characters,
but spaces are not allowed. You must enter a user name and password when you
select client mode.
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.
Table 101 VPN Rules (IKE): Gateway Policy: Edit (continued)
LABEL DESCRIPTION
