In the console tree of ISA Server Management, click
Virtual Private Networks (VPN).
In the details pane, click the Remote Sites tab, and
then select the applicable IPsec remote site network.
On the Tasks tab, click Edit Selected
Network.
On the Connection tab, click IPsec Settings.
On the Phase I tab, in Encryption algorithm,
select one of the following:
DES, to use the DES algorithm and a single 56-bit
key.
3DES, to use Triple Data Encryption Standard algorithm,
and three unique 56-bit keys. This option offers higher
security.
In Integrity algorithm, select one of the following:
SHA1, to use a 160-bit key (stronger).
MD5, to use a 128-bit key (faster).
In Diffie-Hellman group, select one of the following:
Group 1 (768 bit), to generate 768 bits
of master key keying material.
Group 2 (1024 bit), to generate
1,024 bits of master key keying material (stronger
security).
Group 3 (2048 bit), to generate
2,048 bits of master key keying material (strongest
security).
In Authenticate and generate a new key every, type the
time interval at which the master key should be generated,
triggering reauthentication.
Notes
For more information about VPN, see Solution: Virtual
Private Networking in ISA Server 2006 on the Microsoft
ISA Server TechCenter Web site(http://www.microsoft.com).
To open ISA Server Management, click Start, point to
All Programs, point to Microsoft ISA Server, and then
click ISA Server Management.
For ISA Server 2006 Enterprise Edition, expand
Microsoft Internet Security and Acceleration
Server 2006, expand Arrays, expand
Array_Name, and then click Virtual Private
Networks (VPN).
For ISA Server 2006 Standard Edition, expand Microsoft
Internet Security and Acceleration Server 2006, expand
Server_Name, and then click Virtual Private
Networks (VPN).
Important
When you use a stronger group for the Diffie-Hellman settings,
the secret key derived from Diffie-Hellman exchange has greater
strength. Use Group 2 when required for interoperability with
Microsoft Windows Server 2003, Windows 2000 Server,
and Windows XP.
Get latest ISA Server content at ISA
Server Guidance.
Send
feedback about this page.