Chapter 4
Advanced Configuration
49
10/100 8-Port VPN Router
the Authentication Key will be automatically completed
with zeroes until it has 40 hexadecimal values. Make sure
both ends of the VPN tunnel use the same Authentication
Key.
Advanced
For most users, the settings on the VPN page should suffice;
however, the Router provides advanced IPSec settings for
advanced users using the IKE with Preshared Key mode.
Click
Advanced
to view the Advanced settings.
Advanced
Aggressive Mode
There are two types of Phase 1
exchanges, Main Mode and Aggressive Mode.
Aggressive Mode requires half of the main mode messages
to be exchanged in Phase 1 of the SA exchange. If network
security is preferred, leave the Aggressive Mode check box
unchecked (Main Mode will be used). If network speed is
preferred, select
Aggressive Mode
. If you select one of
the Dynamic IP types for the Remote Security Gateway
Type setting, then Main Mode will be unavailable, so
Aggressive Mode will be used.
Compress (Support IP Payload Compression Protocol
(IP Comp))
IP Payload Compression is a protocol that
reduces the size of IP datagrams. Select this option if you
want the Router to propose compression when it initiates a
connection. If the responders reject this proposal, then the
Router will not implement compression. When the Router
works as a responder, it will always accept compression,
even if compression is not enabled.
Keep-Alive
Keep-Alive helps maintain IPSec VPN tunnel
connections. If a connection is dropped and detected, it
will be re-established immediately. Select this option to
use this feature.
AH Hash Algorithm
The AH (Authentication Header)
protocol describes the packet format and default
standards for packet structure. With the use of AH as the
security protocol, protection is extended forward into the
IP header to verify the integrity of the entire packet by use
of portions of the original IP header in the hashing process.
Select this option to use this feature. Then select
MD5
or
SHA1
. MD5 produces a 128-bit digest to authenticate
packet data. SHA produces a 160-bit digest to authenticate
packet data. Both sides of the tunnel should use the same
algorithm.
NetBIOS Broadcast
Select this option to allow NetBIOS
traffic to pass through the VPN tunnel. By default, the
Router blocks this traffic.
NAT Traversal
Select this option to use this feature.
Both the IPSec initiator and responder must support the
mechanism for detecting the NAT router in the path and
changing to a new port, as defined in RFC 3947.
Dead Peer Detection (DPD)
(This option is available for
VPN tunnels only, not group VPNs.) When DPD is enabled,
the Router will send periodic HELLO/ACK messages to
check the status of the VPN tunnel (this feature can be
used only when both peers or VPN devices of the VPN
tunnel use the DPD mechanism). Once a dead peer has
been detected, the Router will disconnect the tunnel so
the connection can be re-established. Specify the interval
between HELLO/ACK messages (how often you want the
messages to be sent). DPD is enabled by default, and the
default interval is
10
seconds.
Click
Save Settings
to save your changes, or click
Cancel
Changes
to undo them.
VPN > VPN Client Access
The
VPN Client Access
screen allows you to manage access
for Linksys QuickVPN clients. (The Router supports up to
50 Linksys QuickVPN clients free of charge. If the Router
you have only supports up to ten clients, then upgrade
its firmware. Refer to “Appendix F: Firmware Upgrade” for
instructions.)
VPN > VPN Client Access
VPN Client Access
For each QuickVPN client, do the following:
Export a client certificate.
1.
Configure a user name and password.
2.