Very odd, but dumb cable modem/router question

[Tact1C]

Hello

I have comcast cable with a Motorola SB4200 Surfboard cable modem. You can plug it up with either USB or Ethernet. I have it using usb, and it works perfectly fine. However, when i hook up a ethernet ( needed for my router [ linksys ] ) my internet does not work. The modem still has all of the lights on, and my computer ( running windows xp pro ) reciginizes when you put the ethernet in/out of the lan card in the back of my computer.

I have never hooked up a router, and I finally got one, and I really wish I could get it to work

ANY info that might help would be greatly appreciated.

Thanks for your time, and have a nice day.

 

[nordlaw]

Tact1C, I may be missing your question entirely, first you should have the modem connected to the WAN port of your router, then the computer to the router's LAN port. The router's primary purpose it to facilate communication between two networks - in this case, the WAN (ISP's network/Internet) and your LAN (just your computer at this point, I gather).

The router may require some extra configuration depending on whether your are on a PPoE network (not common on cable ISPs, I believe) or just have a direct connect. Also, if you have a static IP, you may have to set that as well. Your ISP can help you with this info.

But, assuming everything is assigned dynamically, with no PPoE involved, just hooking everything up the way I described might do it.

Hope that helps a little.

 

[Thoreau]

If Comcast is anything like Cox HSI, there is one more step that will come into play
Reboot the cable modem =)

If Comcast uses the MAC address of the computer connected on the modem's ethernet port, then a reboot should tell the modem to release that information and look for it again. This is how some ISP's handle setups where it is possible to purchase additionl IP addresses. The modem is configured to dish out access to the first X MAC addresses it see's after booting up. (Where X = the number of IP's you have from your ISP, usually just one.)

Anyway, rebooting the cable modem will allow it to reset and see the new MAC address of your router, which should help get things rolling along.

I would say that you could try cloning your computer's MAC address to the router, but since it was normally connected via USB, I don't think it would actually have one.

Of course, if all else fails, pray that your ISP has decent tech support. =)

 

[nordlaw]

Good point, Thoreau. Thanks.

 

[JackMDS]

If it is Cable Intrenet you probably need to clone the MAC number.

Connetion should look like this.

Diagram of Broadband Connection with Cable/DSL Router.

And reading the Router's manual should help too.

 

[Kadarin]

JackMDS: Comcast, at least in my area (San Jose, CA) does not require cloning the MAC. Once the modem's activated, you can connect it to anything. However, mine is an SB3100 that does not have a USB interface. (I specifically requested this.)

 

[JackMDS]

Quote: "JackMDS: Comcast, at least in my area (San Jose, CA) does not require cloning the MAC.".

Yeah, Comcast is "schizo" in some places they use MAC numbers in other thye do not.

Howver they do not publish the info. that is why I use the word "Probably".

 

[gunrunnerjohn]

I think Comcast has been moving away from using anything but the modem's MAC address. Since they are running around the country buying up little cable operations, they frequently have a number of schemes in active use at any one time...