Is there a way to connect a phone to a UCM in an upstream router?




I’m trying to design a system for a building with 12 apartments using grandstream devices, i’m using gwn7000 as routers, an ucm 6208 central and several grandstream ip phones.

What i’m trying to do is, to conect a single ISP to the building, and with a gwn7000 distribute the ISP bandwidth to the apartments that will have each another gwn7000, giving the freedom to manage different bandwidths, but i’d like to have a centralized phone system into the building, using the UCM… is there a way i can conect the phones that are on an apartment’s network to the UCM that’s on the main building’s network?.

The ucm would be in the same network that the apartment’s routers but i’m not sure if i could configure the router to allow ip phones to connect to the main network without compromizing the security of the main building network and the other apartments, i’d live to avoid connecting 2 utps to each apt.

Thank you in advance for any help.


if you do a double nat you are wrong at the start


Just use one router and supply an vlan ethernet connection to each unit via a suitable poe switch.


You can achieve this in many ways…

Door entry via a GDS3705 device with fobs for each apartment user…1 x GXW4200 series Gateways to cover apartment analogue handsets (cutting down the UTP needs as it is just 1 pair of wires needed), 1 x UCM 6208 to provide the intercom and extension dialling, providing access to the external ISP.

Ideally placing the UCM and gateways into a vlan by themselves and 1 each for every apartment will allow separation as needed.

Any more than the above information for you to use becomes engineering and design which I would suggest to pay for someone locally to perform.

VLan tagging for each apartment, 1 pair from the 4 pair ethernet cable, the centre white blue/blue wire for an analogue device to each apartment.

Else using just VLan tagging to connect the apartments use a CDP style poe switch to allow for protocol separation with auto vlans.