How do I setup my Zoom ADSL modem (X3,X4,X5) to use an IP Phone on a SIP network such as the Delta3/IConnect network ?

To connect to certain SIP based networks, such as IConnect from Delta3, you will need to create a Virtual Server in the advanced setup of the Zoom ADSL modems and open the following two ports - 5060 TCP and 5060 UDP.

NOTE: This is important as setting up a DMZ will not work.

Virtual Server
Open the Zoom Web Console, click Advanced Setup, and then click the Virtual Server button.

Add the Virtual Server settings for the TCP port by entering:
Public Port: 5060
Private Port: 5060
Port Type: TCP
Host IP Address: 10.0.0.15 (where "15" is your telephony devices IP address)

Next, add the Virtual Server settings for the UDP port by entering:
Public Port: 5060
Private Port: 5060
Port Type: UDP
Host IP Address: 10.0.0.15 (where "15" is your telephony devices IP address)

Once the two entries are set click on Save Settings >> Confirm >> and Reboot.

Finally, make sure your Telephony Device is set with the IP address of 10.0.0.15 and a default Gateway of 10.0.0.2