I am trying to setup a VPN between 2 sites over 4G using Alcatel L800 dongles connected to the WAN3 port of each router. The router at both sides are 2860's with the latest firmware provided from Draytek (beta_0414, build time Jan 3 2014 - to get the dongle working).

The problem I have is that I can't create a connection between the 2 4G dongles. I can go from 1 4G dongle, to an ADSL connection on the remote side, but cant connect when the remote site is using the 4G dongle. Also, I can't connect from my 2930 Draytek to either router if I try and use the 4G dongles on the 2860's, but if I use an ADSL connection on the 2860's then the VPN link gets created fine.

Has anyone tried this configuration? Can the router receive a VPN connection on WAN3 using this firmware?

Any help would be appreciated.

Thanks,

Martin

Is the ISP providing a proper routed or NATted WAN IP address at each end? If the latter, then it may be interferring. Test with PPTP temporarily (assuming you're using IPSec). Also, try agressive mode for IPSec.

Did you find a solution to this challenge ?

I've been trying to set up a backup route into my home router (2860n+) via a USB dongle on Three. My testing so far is indicating that the default PPTP port, as well as most other common service ports are filtered/blocked for incoming traffic. The only exception I've found is port 5900 (Vnc). However, there seems to be no way to change the PPTP port from the default - at least not via the web interface.

I suspect your problem was the same thing - mobile networks filtering or blocking incoming traffic

The best solution is probably using one of these:

http://aa.net.uk/telecoms-mobile-data.html

"You can send and receive any legacy IP packets regardless of IP with no anti-spoofing or filtering. This includes routing blocks of legacy IP."