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Documentation from the windows team is here: http://www2.slac.stanford.edu/comp/windows/docs/VPN/VPN.aspx
Why are we changing over to a new VPN system
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There is a fixed timeout of 8 12 hours after which your VPN connection is disconnected. There is also a non-activity timeout of 20 minutes which takes effect if no network traffic passes for 20 minutes.
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