Monday, December 12, 2016

Notes about unlocking a Vonage VDV23 VoIP box

I got a used Vonage VDV23 VoIP box to play with. Vonage seems expensive and limited compared to other VoIP providers like, so I decided to unlock the box for use with other providers. A guide is available, but I ran into various problems trying to follow it, and this was quite an adventure. You can access the guide for free, but need to register at and log in there. The comments here are meant as a supplement to the guide, not a replacement.

Note that buying this device for use with Vonage may be pointless. Vonage will give you a new adapter if you sign up, and may not allow you to use an old one.

Firmware loading via TFTP

Always use the internal phy. It will tell you if autonegotiation worked and you got an Ethernet connection. I never had any success whatsoever when I selected external phy.

Network connectivity from the bootloader sometimes seems terribly unreliable. Pinging the VDV23 only worked once. Other times it at best answered a few pings, often with delays of more than a second. Received pings also spit out error messages to the console. Trying to ping first may even break subsequent TFTP attempts. Don't bother testing the network connection with ping; just try TFTP.

After trying my main PC and router, I ended up using the Ethernet port on this Inspiron 6400 laptop. Also, I was always setting up the network immediately after startup, not later on via the menu. When I did this, TFTP always worked.

The "Board IP Gateway" must exist, because the VDV23 will perform ARP queries for it when starting TFTP. Yes, it will even do this if the address is within the LAN. I just set it to the TFTP server address.

Getting the Admin password

Ignore the password at BF7F0118. Yes, there seems to be a password there, but I could never log in using it. If the password at BF3D00FA is all zeros, you didn't wait long enough for the VDV23 to download the password from Vonage and configure itself. If you wait too long, it will start upgrading firmware.

The first time I couldn't log in with the password from BF3D00FA either. I'm not sure if the "safe" vdv21-3.2.6-na_boot.bin firmware needs to get the password over the Internet from Vonage again. It may also start upgrading firmware if you wait too long. So, you need to disconnect from the Internet and continue with the rest of the guide.

Configuring SIP

I chose to configure via the XML file. First I tried to use an address accessible from the blue WAN port, but I didn't see any HTTP requests. Then I chose the default address and it worked via the yellow Ethernet port.

The device always sends an HTTP request soon after booting, so I was just unplugging it and plugging it back in to change the configuration. Seems like it first configures itself using stored parameters. Then if the XML file has different parameters the phone light will go out for a while as it reconfigures itself. Don't take the phone off hook during that process, because it will be testing the line. You may end up with a blinking phone light and a console complaint about the ringer equivalence number (REN) being too high.

Pay attention to the dialPlan lines. The one in the provided XML isn't enough for some numbers, leading to a fast busy. I couldn't figure out how to support 2 and 3 character * codes except using *xx.T, which waits for a timeout before proceeding with the call. For experimenting, I could reconfigure dialPlan once from the console and see immediate results.

I forwarded port 8660 because it is localPort in the XML, but am not sure if that was necessary. The device is meant to be directly connected to the Internet and act as your gateway, providing NAT while prioritizing VoIP traffic. Since I'm still playing with it, I'm not going to do such a drastic change to my network.

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