2Wire manufactures several devices that act as both a modem and a router. Models from this manufacturer have caused several issues with VoIP, and SIP specifically. Cloud9Phone recommends making the following changes to your 2Wire setup in order to best accommodate the necessary traffic.

1. Ensure the computer is connected to the router.

2. Launch a web browser, navigate to

  • Please Note: This is the 2wire’s default IP address. However, the IP address may be or vary by provider.

3. Enter the Username and Password then click “OK”.

  • Default Username: admin
  • Default Password: password.

4. Click “Firewall”.



5. Click “Advanced Settings”.



6. Ensure all boxes under “Attack Detection” are unchecked, then click “Save”.



7. Open a new browser window, navigate to http://gateway.2wire.net/management.

8. Enter the Username and Password,  then click “OK”.

  • Default Username: admin
  • Default Password: password.

9. From the left navigation menu, click “Configure Services”.






If the above process does not resolve dropped call or one-way audio issues, you may need to call your ISP. In the United States, most 2Wires are sent out by AT&T. If this is your ISP, you will need to call their technical support hotline and ask to speak to a Tier 2 technician. When connected, inform the technician that you need to “open up all the ports.” This should allow your phone to being working normally.

If these steps do not work or are not possible, the last option would be to put the device into Bridge Mode.


AT&T’s U-Verse service provides television, internet and phone service in a combined device that incorporates a 2Wire-style modem/router combination. Therefore, these devices typically cannot be put into Bridge Mode due to their support for these other services.