Jan Just, According to my experience, for OpenVPN UDP isn't better than TCP in case of bad connection with excessive packet loss. TCP has more sophisticated mechanisms than OpenVPN's --ping and --ping-restart. But the ability of OpenVPN to mask out the disconnect is really remarkable.
On 19.12.2014 13:47, Jan Just Keijser wrote: > Hi, > > On 17/12/14 04:26, Daniel Miller wrote: >> Slightly off-topic - but... >> >> I've noticed that my "normal" or direct ssh connections from my home >> (Windoze) to my office (Linux) can be subject to instability - >> particularly if I simply leave PuTTY connected and idle for a while at >> some point it will get disconnected. However...if I activate my OpenVPN >> tunnel (standard routed UDP), and then ssh to the office via the VPN - I >> can leave it online for days without interruption. It just works. It's >> so reliable it's boring. >> >> This begs the question - how is OpenVPN providing such apparent superior >> connection quality for ssh compared to a direct connection? >> > this is actually one of the great benefits of using OpenVPN over UDP - > it will mask out a flaky wireless or internet connection. > A standard SSH connection is TCP based. If such a connection is > disrupted for some reason (actual TCP disconnect) then the SSH session > can be stopped. OpenVPN over UDP is stateless, hence it does not really > know if the UDP connection is "gone" - it will simply keep sending > packets and wait for answer (for a certain period of time). So, if your > home internet connection drops out for , say, 20 seconds then the > OpenVPN connection remains intact and so will all TCP-based sessions > that are running over it. > > HTH, > > JJK > > > > > ------------------------------------------------------------------------------ > Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server > from Actuate! Instantly Supercharge Your Business Reports and Dashboards > with Interactivity, Sharing, Native Excel Exports, App Integration & more > Get technology previously reserved for billion-dollar corporations, FREE > http://pubads.g.doubleclick.net/gampad/clk?id=164703151&iu=/4140/ostg.clktrk > _______________________________________________ > Openvpn-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/openvpn-users -- Best regards, Pavel ------------------------------------------------------------------------------ Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration & more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=164703151&iu=/4140/ostg.clktrk _______________________________________________ Openvpn-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/openvpn-users
