My ISP is Orange Internet, I have recently ditched my crummy "livebox" and moved to a more stable BT Business Hub with the firmware flashed back to the original SingTel ROM. The thing works great apart from one problem: I'm unable to get my VOIP line to work.
I called Orange and apparently their VOIP service is tied to a specific MAC address which they are unable to change; they just enter the serial number of the livebox and it looks like their WAN-side MAC is hidden. My SingTel router allows changing the MAC address, but I'm unable to get the external MAC address of the livebox in order to spoof the correct one.
So we arrive at my question: How do I find the external MAC address of a black-box ADSL router which connects over PPPoE?
I'm thinking that if I had an ADSL modem with GNU/Linux drivers, I may be able to plug the router into the modem and record the traffic it sends using Wireshark. As the oE in PPPoE stands for "over Ethernet", I'm guessing Wireshark should have no problems finding the MAC address of my router this way. I don't actually have one though, so before I go out and buy one:
- Are my assumptions sound?
- Will I need a special sort of cable or will the link layer work with a standard modem cable?
- Is there a better way to do this?