| reply to forrestin
Re: Linksys PAP2 change from Vonage to Broadvoice To correct some misunderstandings up above, from a real life network engineer:
I set up a TFTP server on my machine and made sure that ls.tftp.vonage.net is pointing to my machine (192.168.2.1) in my hosts file. The hosts file on the server is irrelevant. The PAP doesn't look at the hosts file on your server.
What I think I'm seeing is that the PAP2 gets a DHCP address, then checks to see what MAC address
ls.tftp.vonage.net has, MAC addresses only matter, and are only visible, on the local ethernet segment. If you go back and look at your traces, you'll probably find that the MAC the Vonage receives for ls.tftp.vonage.com, if any, is the MAC of your router's LAN interface.
The MAC address(es) of the server(s) at vonage.com will not help you at all.
then pings a couple of static addresses, on non-standard ICMP ports, that must be hard coded into the firmware or configuration. Nope. ICMP doesn't have ports, it has types/codes. You can't "ping" with a "non-standard type." In addition, since firewalls and a few ISP's may filter oddball ICMP traffic, this would cause support nightmares for Vonage because a number of users would not be able to connect. There's no reason for them to do anything this goofy.
The Vonage is undoubtedly getting the IP's for ls.tftp.vonage.com from the DNS server address it receives when it gets its DHCP address, probably from your router. The hosts file on your server won't change that. It then arps for that IP. It will receive a proxy arp reply from your router with the router's MAC address. The trace then shows the PAP sending UDP packets to tftp.vonage.com ... almost certainly tftp get requests. It gets no response after 5 tries to each of 3 different server IP's. It then sends a query to 224.0.0.251, which is multicast DNS, looking for a multicast address for tftp.vonage.com. This fails, because you don't have a multicast DNS server on your local network.
Long story short ... all this trace shows is the PAP trying to phone home, getting valid server IP's from DNS, failing to get a response from any of the tftp servers at Vonage, and giving up.
To try this sort of methodology to break these boxes, you need to set up a completely isolated network, with a DNS server on your local network to give the IP of a local tftp server to the PAP's DNS query. If you wanted to get fancy, you could even put one of the valid server IP's on your own server, give the PAP an address in the same subnet as the valid IP, and dish out that IP from DNS.
But all of that is (relatively) easy. You'd then need a file on your tftp server which is acceptably formatted so that the PAP will swallow it, that sets the password to something you know, or resets the device to non-Vonage factory defaults. Making that file would be very, very hard, I'd think.
Since these PAP's are currently free after $50 rebate at Staples, I sure wish I had a way to use them!
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