sundance-communications.com/forum Forums TDM Business Telephone Systems Samsung Telephones & Systems One way voice with VoIP in 7400

Hi all,

First of all this is the first site I came across with so much information on samsung system.
I really need some help with VoIP issues I am having with my 7400 system. I am really getting desparate for this so here is the issue.
We have OS7400 V4.5. This system is behind firewall. Our remote office is using 4 VoIP phones. Initially we had them configure throgh VPN tunnel and everything works fine. Now we planned to move the traffic through outside instead of through VPN tunnel between 2 offices.
We changed IP tpe to public w/private on 830 and 831. Provided the public IP. Natted this public IP to mcp and mgi IP behind firewall. All ports were opened with no restriction on this IP at all. But the issue is we have audio one way. Remote office can hear me but i cannot hear them. Initially thought some firewall issue with remote office so we connected public line directly to phone to avoid firewall but still same. Disabled MPS as suggested on some posts here but still nothing.
I went through all posts here with similar issue and some experts do have solution for this which cannot be posted. SO PLEASE EMAIL OR IM ME.
I really need this help badly now. Again i saw a lot of suggestions for port issues on firewall but I opened up all the ports just not for this IP but for entire network still nothing.

Please HELP.

How about your remote routers are the ports open on them also what type of routers do you have remotely have had problems using some routers

Can you list the natted ports you have and whether they are TCP or UDP Please.

No need to mention IP addresses (for security) just list what ports forward to the MP40 and what forward to the MGI/ OAS card.

Thanks Gerrya and Badger.

On the remote site my ISP line is directly plugged into the phone. So no firewall or router in between. On my side where 7400 system i hava a sonicwall firewall.

Badger, we had opened up 30000-30031 and 9000-9001 for mgi UPP we tried TCP as well. 6000-6100 for mcp. we also tried opening some 5000 series ports as well. Also tried 40000-40127 related to MPS.

Finally we just opened up everything not blocking any ports.

My IP phones have the same issue, they will be half-duplex unless they are connected through VPN.

Can you get a trace from the system end and then the ip phone end? idealy at the same time.
this will tell us whether the packets are getting to the mgi/oas card.

Do you have multiple mgi cards?

Thanks everyone for their help.

Finally figured this out through packet trace. Apparently keeping everything open on firewall doesnt always work. In our firewall we had one public IP forwarding to both MGI and MCP private IP behind firewall. Through trace we realized that incoming voice packets on port 30000 were getting forwarded to MCP IP instead of MGI which handels voice part.

Ended up creating separate rules for MGI and MCP IP's on firewall.

Now for some reason both way voice between IP phones has problem when dialed as extension.

For eg. I have 2 IP phones at remote location. Dialing extension of one IP phone from another, voice doesnt work. Dialing extention from non ip to ip and other way round is not a problem.

are you using dsl at the remote sites?

Forward the MPS (40000-40127 udp) to the oas card will fix your issue, as the ip phones are remote