Security issues with a VPN and DSL?

What are the security issues when you set up a VPN on a DSL line? Does DSL support a VPN connection?

Whether you use the DSL line as a user to connect to an Internet VPN-accessible service or as the inbound connection via a connected VPN server, the security issues are essentially the same as with any other TCP/IP transport link. Many T-1 circuits are delivered by service providers today using DSL technology. The issues with DSL connections and VPNs are whether the connections involve fixed or dynamically assigned IP addresses, and how many layers of Network Address Translation (NAT) are involved between the VPN client and the server. Using DSL connections with VPN client software is getting easier as the products mature, but older versions of many products won't support clients using private IP addresses behind firewalls and routers performing NAT. If you want to run a server on your DSL connection, get a fixed static IP address or dynamic DNS services for the server from your service provider so your users can reliably find your host on the network. Again, be careful choosing your VPN package if you need to support clients coming from behind other organizations' firewalls. DSL technology can support VPN connections. Whether the DSL technology available to you can support the VPN connection you need is a question for your service provider.

As a network architect at Change at Work in Houston, Blass understands the strain of developing and managing networks. Send your problems to dr.internet@changeatwork.com

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