stupid networking question -- cable modem

[ncage]

Ok here goes. I know its a stupid question but ive never really attached on directly to a computer. It has always been attached to a router. Anyways don't cable modems have a dhcp server inside? I am in the process of building a OpenBSD firewall and i noticed that when i plug the cable modem directly into a network card and try to get a dhcp address from it...it fails. If they don't have internal dhcp servers how does the router know what ip address to use for the cable modem side of things?

thanks,
Brent

 

[bsobel]

Originally posted by: ncage
Ok here goes. I know its a stupid question but ive never really attached on directly to a computer. It has always been attached to a router. Anyways don't cable modems have a dhcp server inside? I am in the process of building a OpenBSD firewall and i noticed that when i plug the cable modem directly into a network card and try to get a dhcp address from it...it fails. If they don't have internal dhcp servers how does the router know what ip address to use for the cable modem side of things? thanks, Brent

The typically have a dhcp client in them to get their address (which may on a different network than what you see). They pass thru your dhcp requests to the network which runs a normal dhcp server.

Dumb question, are you using a cross over cable when you do the direct connection?

Bill

 

[JackMDS]

The DHCP server is at the ISP's central system, the modem is just a "Dumb" Bridge like unit.

You might have a MAC authentication problem, http://www.ezlan.net/broadband.html

 

[JackMDS]

oops!