Configuring a Cox Cisco DPC3829AD Router

The ideal network involves your Internet Service Provider (ISP) connecting onsite to a stand-alone modem that connects to a router, preferably a router recommended to you from Nextiva. If you have more devices on your network than ports on your router, you can connect a switch to your router to expand the number of ports.

NOTE: If SIP ALG is enabled (depending on firmware), it cannot be disabled. This will cause intermittent call failures due to deregistration, as well as problems with phone features. Polycom phones will experience these same issues, and Nextiva recommends using Google DNS servers as a temporary solution.


To Configure Firewall and DNS Server:


  1. Locate the IP address of the router and enter it into the address bar of your web browser with the following credentials:
  • Username: admin
  • Password: admin
  1. Select Security > Firewall.
  2. Uncheck Block Anonymous Internet Requests.
  3. Click Save.
  4. Select Setup > LAN Setup and enter the following required information:
  • LAN 1 Static DNS 1:
  • LAN 1 Static DNS 2:
  • LAN 1 Static DNS 3: Your ISP’s DNS Server. If unknown, your ISP will be a great resource.
  1. Click Save to apply the configuration.


NOTE: It is not recommended that this router is used with Nextiva services. The configuration steps presented above may be a temporary resolution to audio and feature issues. If the router is able to be bridged (dependent on firmware and your Internet Service Provider), connect a router recommended to you from Nextiva to the bridged device. It is always recommended that an experienced Network Administrator make any changes to the network.

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