3Com OfficeConnect User Manual page 59

but does not apply to PPTP connections. If PPTP only is enabled,
This Router's ID field does not appear.
If you require main mode IPSec connections then this value must
be the public IP address of the Router.
Figure 59 VPN Mode Screen
L2TP Configuration
If you have enabled L2TP over IPSec you must enter the following
items:
In the IPSec Configuration field, enter This Router's ID as an
1
Internet IP address, the DNS address of the unit or the name of
the Router that you are configuring. This value is common across
all IPSec connections but does not apply to PPTP connections. If
PPTP only is enabled, This Router's ID field disappears.
In the Router ID type field, Select one of the following:
2
IP address (default). This should be the public WAN address of
the Router.
The DNS address of this unit.
A name for this unit. Used when it is not possible to use one
of the other modes, for example, if the IP address keeps
changing.
In the L2TP Configuration field, enter:
3
the Domain Name as an IP address. A Domain Name locates a
website on the Internet.
The IPSec Shared Key. This is the key for the connection and
is a combination of letters, numbers and punctuation and can
be up to 64 characters in length. 3Com recommends that the
key and password are not the same. The user will need to
know the IPSec Shared Key to enable connection.
In the Encryption Level field, choose the encryption type from
DES, 3DES or AES. 3DES is more secure than DES but may
take longer to encrypt and decrypt. AES provides the highest
security but will take longer than 3DES to encrypt and
decrypt.
3DES and AES are not shipped with the Router as standard due
to international restrictions on encryption. If your country permits
their use they can be downloaded from the 3Com web site at
http://www.3com.com/
4 To set up the Router for L2TP over IPSec you must allocate IP
addresses from the Router's LAN for use with L2TP over IPSec.
59