Perle Systems SCS8C DC User Manual

Page of 460
 242
VPN
VPN
Overview
A Virtual Private Network (VPN) creates a secure, dedicated communications network tunnelled 
through another network.
You can configure the IOLAN for:
z
a host-to-host Virtual Private Network (VPN) connection
z
a host-to-network VPN connection
z
a network-to-network VPN connection
z
or host/network-to-IOLAN VPN connection (allowing serial devices connected to the IOLAN to 
communicate data to a host/network). 
In addition to being able to configure up to 64 IPsec tunnels, you can configure an L2TP/IPsec tunnel 
that will allow hosts to create a VPN tunnel to the IOLAN. The L2TP/IPsec VPN protocol is required 
by the Windows XP
®
 operating system. Later versions of Windows
®
 may support both VPN 
protocols, however check with the Windows
®
 documentation that came with your Windows
®
 pc.
Functionality
The information in this section applies only to setting up IPsec VPN tunnels, not L2TP/IPsec VPN 
tunnels.
The IOLAN can be configured as a VPN gateway using the IPsec protocol. You can configure the 
VPN connection using two IOLANs as the local and remote VPN gateways or the IOLAN as the 
local VPN gateway and a host/server running the VPN software as the remote VPN gateway.
If the VPN tunnel is being configured for an IPv6 network that is going through a router(s), the 
router(s) must have manual IPv6 address entry capability, similar to what Windows Vista
®
 provides.
VPN servers/clients can support various VPN parameters. However, the following parameters are 
REQUIRED to be set to the following values to support a VPN tunnel between the IOLAN and a 
VPN server/client:
perfect forward secrecy: no
protocol: ESP
mode: tunnel (not transport)
opportunistic encryption: no
aggressive mode: no
Common Name
An entry for common name; for example, the host name or fully qualified 
domain name. This field is case sensitive in order to successfully match the 
information in the peer SSL/TLS certificate.
Data Options: Maximum 64 characters 
Email
An entry for an email address; for example, acct@anycompany.com. This field 
is case sensitive in order to successfully match the information in the peer 
SSL/TLS certificate.
Data Options: Maximum 64 characters
Note:
Before you enable/configure any VPN tunnels, you should configure any exceptions or you 
might not be able to access the IOLAN except through a VPN tunnel or the console port. See 
 for more information about exceptions.
Note:
If you are configuring IPsec and/or L2TP/IPsec, you must also enable the IPsec service 
found in 
Security
Services
 navigation tree.