[ale] Modem/router config for Comcast

[JD]

On 07/29/2012 01:35 PM, Jim Lynch wrote:
> I have purchased a modem and router to replace the Comcast supplied 
> equipment and am wondering how to configure same.  I read in a recent 
> thread about asking the company to configure the modem as a pass-through 
> device.  That's what I'm currently doing with the existing DSL service, 
> letting the router do the PPPoE authentication.  Since I haven't gotten 
> any user/pw info I'm making a wild guess that cable modems don't use 
> PPPoE??   This is a residential installation.

Cable uses DOCSIS with network identifier (like a MAC) tied to the physical
modem, not PPOE. You will need to call Comcast, tell them you have a new modem
and want to use it.  They will talk you through the process. It is a hassle, but
it is their network and they will control the modem.

There is no userid/password needed to connect to the network. Those are needed
just to access your ISP settings and email, not the network.

Did you get 1 device or 2?  It is unclear.
* modem device + router device or
* combined modem+router in a single device?

I hope it is DOCSISv3. The specific make + model would be helpful.

> 1. So the questions are, can I get the drones supporting a residential 
> installation to configure my modem as a pass-through?
> If I do, what's the connection type?
> Is there an authentication mechanism I'll need a user/pass for?

Every single purpose DOCSIS modem I've had was in bridge mode.  Only those
modem+router combo devices do more.

> 2. Or am I going to have to leave the modem alone and  get an IP from 
> the modem via DHCP?

Your public IP will be DHCP, but in my experience, the public IP on residential
service only changed 4 times in 12 years.  Your internal LAN IPs don't come from
a standalone modem. That is what a router does or some other DHCP server that
you run on your network. Your choice.

> I'd rather not have two DHCP servers between me and the network, if 
> that's possible.

The comcast public DHCP has nothing do to with your DHCP for your NAT network.
It isn't like DHCP leases expire every 10 minutes.  For your internal network
you can control the lease time completely.

> I know how DSL works but I haven't had any experience with cable to 
> date.  I googled for info but all I could come up with was how to 
> accomplish #2.

Service from both DSL and Cable companies can disappoint, but I've had much
fewer issues than I hear from my friends using DSL.  When I have had issues and
it wasn't corrected for the entire area, it was due to old COAX in the ground
and long runs from the street.  Having thick and fresh RJ-6 installed rocks.
Whenever the chipmunks start eating into the cable every 8 yrs or so, I get a
new line dropped.