[lcotton]

Hi

I am currently using virgin media broadband, have put the modem (Hub 3.0) into modem mode and hooked up a wireless router (currently a Belkin).

All this has been working fine for a while, but I'd like to change the router I am using and when I do so I do not get assigned a WAN address.

I have not had a chance to dig deeply in to this, but I am trying to work out what has to happen to get the address assigned.

I assume the router sends a dhcp request out of the WAN interface to the ISP dhcp server which eventually responds with a leased WAN address for the router.

Is that correct ? Or does the modem itself somehow get involved (till now I've been assuming that in modem mode all layer three comms comes from the router and simply gets forwarded to the coax interface, but I guess that could be an invalid assumption).

I'm trying to work out:

how the ISP server to send the request to is specified, or if it needs to be specified at all (router config, modem config ?)

if the dhcp server address does not need to be specified how does the virgin media dhcp server know the request is for it (and conversely other dhcp servers know to ignore it) ?

how virgin identifies me as a user - does it use the mac address of the router, mac address of modem or something else entirely ?

and how do I configure things such that the correct 'userId' is included in the dhcp request ?


Does anyone know where I can find an overview (sequence diagram ?) of how the wan ip address is assigned to the router for virgin broadband ?