We've set up a host to host VPN tunnel with OpenSwan IPSEC. When we run performance test outside the tunnel (ipsec stopped) we get a bandwidth speed of approximately 800 Mbps. Tested with:
iperf -s on one side
iperf -c IP -t 60 -i 4 on the other side
However, when we start the ipsec tunnel and run exactly the same test we only obtain a speed up to approximately 85 Mbps.
Anyone have an idea if, and how, to configure a bandwidth to be used with an ipsec tunnel?