[Openswan Users] Persistant connections over openswan tunnel

[Chris Picton]

Hi all

I am trying to duplicate an effect I see with openvpn, but using
openswan.

I have two gateway servers running openvpn, with separate networks
behind them being routed through the tunnel.  The server's do not have
static IP addresses, and the IP can be changed (by my ISP) at any time.
This causes the openvpn tunnel to drop and be re-established.

The routing through the tunnel does not drop, however.  If I am
connected from a client on network A via ssh to a machine on network B,
when the server's IP changes, the connection hangs for a few seconds,
but when the tunnel is brought back up, the connection continues - it
does not drop.

As far as I can tell, this is because the openvpn tun device does not go
down, and it keeps the same ip range for the tunnel.

Is this scenario possible with ipsec?  

Any help would be appreciated.

Regards

Chris