Tuesday, December 05, 2006

Windows Routing on VPN Connectivity

Having installed a serious amount of VPN systems (Virtual Private Networks) over the last 6 years, I still get asked about the fact that when some users are connected to the VPN - normal Internet access goes extremely slow to non-existent.

The reason for this is because the default routing tables in Windows sends 'all' traffic down the VPN link and to the remote Internet Gateway. Essentially you are surfing the Internet through the VPN link and via the Internet connection at your office/work!

However, this is simply fixed in Windows by going to the properties of the VPN connection (right click, select Properties).

Now select the Networking Tab from the Top and then double click 'Internet Protocol (TCP/IP)'.

From this next window, select 'Advanced' and simply remove the tick from the box which says 'Use default gateway on remote network'.

Now click on OK to everything until you get back to your desktop and then run your VPN connection again - hey presto, all traffic destined for the remote network will go down the VPN, but everything else will use your normal internet gateway connection.

2 comments:

Benjamin Dyer said...

Hey Carl, have you thought about looking into Cisco VPN concentrators? OK it might be a little over kill for the SME market, but you can configure local traffic to stay local which would solve your speed issues.

cwcrawley said...

Yeah - cheers for that Ben... as you say, most of the requirements I get don't warrant Cisco gear and are usually looking for lower-end solutions (open source etc) - but a valid point nonetheless!