Remote Extention UDP Blocked

[djboxny]

Hi all, I currently have a 3cx pbx on a static ip, Firewal check all pass,
i recently sent a Grandstream handytone 502 to the dominican republic, over there i get the internet thru a cable modem with a nat router in the modem, Can someone please advice on wich ports i need to open on the modem/router in the external extention, Current ports for external extention are 9000-9050

Also the grandstream is saying UDP blocked.

 

[mfm]

Hi,

It would be ideal if you tried to use tunnel to avoid any blocked ports and problems with your provider, it will create a direct connection to the PBX.

 

[djboxny]

How can I use the tunnel on a grandstream 502, I know there has to be a workaround. Since I don't want to use the 3rd proxy, the remote extention is sending out data in ports of range of 52000- 55000 no idea why

 

[leejor]

You really shouldn't have to do anything to the router at the far end. I've connected an ATA to many routers with no changes in the router (actually , no access to even make changes in the router) and it has worked well in the majority of cases. That said, there can be some routers that don't play well with VoIP, or, have in-built ATA's that are blocking ports. Some equipment supplied by companies that also provide VoIP services may be set-up to block any other use of VoIP over their equipment (modem/router). It's unfortunate that the router is built into the modem, otherwise you could connect the Grandstream directly to the modem and allow it to pick up a public IP.

Have they tried putting the Grandstream IP into the DMZ in the router?

To use the tunnel, you will either have to use the 3CX softphone on a PC at the far end, or, be running the 3CX proxy server on a PC at the far end, then point the Grandstream to the proxy server.