SSL VPN Performance is horrible using TCP or UDP

Hello Shawn,

this sounds like an MTU problem to me on either both links or at least one of them.

Normally, IPsec tunnels are more likely to have this kind of problem, but we should check this.

The VPN is set to 1300 on both ends

OK, this sounds good. We should exclude that as possible reason.

Did you by chance enable "compression" in SSL global settings?

Yes it is on. We were told not to turn it off.

Yes it is on. We were told not to turn it off.

OK, we found it.

You should turn it off definitely.

And, while working on this, you should check the debug setting to be turned off, as well.

Debug is off, so I guess this means all the users will need to download a new profile again...

I have to wait until we have tested this before I can Verify it as an Answer.  Ich hoffe das es geht :-)

Changing the Debug Mode setting should not result in a need to download a new profile; changing the compression setting will (and I agree with the others, turn that off).

compression is now off, no change in performance at all.  Do I need to reboot the firewalls?

I'm starting to think we should try IPSEC for the users who need it, I've read that it is faster than the SSL.

No reboot should be needed.  

You have an interesting problem there, and I haven't seen a speed issue like this in a while.  Though in the recesses of my mind, I recall a couple of scenarios:

1)  The WAN link on the firewall had a speed / duplex mismatch with the ISP gear -- granted I have not seen this in many moons but I have before.  Causes strange behavior.

2)  I don't see it mentioned here -- have you disabled UDP flood protection?  That can cause issues with UDP streams.

3)  Also, haven't seen it here, have you tried testing, say, from a directly connected link?  There could be some throttling happening at your ISP, the client's ISP, or in between, of that traffic.  YOu can try a different port, etc.

Of course trying IPSEC may work as well -- but more "free" Wi-Fi connections block that usage than others.