The diagrams below show how to connect your Hosted PBX phones to your office network. Having a proper network configuration is critical to ensuring you're getting the most out of your Hosted PBX service.

  • Internet service providers (ISPs) will provide modems that have built in router capabilities. All ISP provided modems have limited features and tend interfere with the quality of the Hosted PBX service. Intermedia recommends using your own network hardware if at all possible because this allows you more control over your network.
  • If you're having issues with your phone service then Intermedia strongly recommends placing your ISP provided modem into NAT passthrough, or "bridge mode".
    • What does bridging mean? Bridging means that internet traffic is passed uninterrupted through the ISP provided modem to another device, in this case one of our recommended routers.

Scenario #1: Without a network switch

ISP provided modem/router only

xThis configuration is NOT RECOMMENDED.  

ISP provided modem router device

Here are where the cables would be connected to each device in this scenario:

Modem only cable diagram


Why is this configuration not recommended? ISP provided modems severely restrict the configurations available to the end user. They typically have SIP ALG and are programmed to be biased toward their own VoIP solution, MANY Intermedia customers with this configuration experience issues with intermittent phone registration loss, one way audio, dropped calls, transfer failures, and a number of other intermittent and strange problems with this configuration. What's the resolution? Configure your network based on one of our recommended scenarios.

ISP provided modem/router connected to a recommended router

 checkThis configuration is RECOMMENDED.

ISP provided modem/router device bridged to a recommended router

Here are where the cables would be connected to each device in this scenario:


Please note that in this configuration it is critical that the ISP provided modem is in NAT passthrough or bridge mode!
Scenario #2: With a network switch

ISP provided modem/router connected to a network switch

 xThis configuration is NOT RECOMMENDED.

Here are where the cables would be connected to each device in this scenario:


Why is this configuration not recommended? ISP provided modems severely restrict the configurations available to the end user. They typically have SIP ALG and are programmed to be biased toward their own VoIP solution, MANY Intermedia customers with this configuration experience issues with intermittent phone registration loss, one way audio, dropped calls, transfer failures, and a number of other intermittent and strange problems with this configuration. What's the resolution? Configure your network based on one of our recommended scenarios.

ISP provided modem/router connected to a recommended router + network switch

 checkThis configuration is RECOMMENDED.

Here are where the cables would be connected to each device in this scenario:


Please note that in this configuration it is critical that the ISP provided modem is in NAT passthrough or bridge mode!