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New Member

How sensitive is VPN to network disruption?

hi guys, hope u can help with a quick question.

Just started with a new company so still finding my feet.

We have 3 remote sites which use IPSEC VPN to connect to our head office where i'm based. Each of the sites has an ADSL line thro our ISP.

Our isp has been having some routing issues. we've found that our remote sites lose connectivity during this disruption. (The guys in the offices phone us up to say theyve lost connection to servers in our head office!)

But our ISP says that the routing issues MIGHT result in some dropped ping packets and a slight slowdown NOT a complete disconnection. they seem to think im exagerating the problem.

my question is, how sensitive is IPSEC VPN traffic to network disruption?

Is it possible that the vpn tunnels get dropped when the isp's routing issues occur?

I am not an expert but i thought vpn traffic would be sensitive to any network disruption as it is supposed to be highly secure?

Please can some experts advise!

New Member

Re: How sensitive is VPN to network disruption?

I would suggest that you put up a Monitoring Server. Big Brother is a good one to use.

I have a few IPSec tunnels that are across the country. The packetloss is typically 3% from the far side, bad ISPs.

IPSec rebuilds fast... when routing is correct. During one of the routing issues, see if you can connect to the remote side. A simple traceroute should tell you where the traffic is dying.