Having trouble with the ethernet connection i can get online but when i connect the 360 to the modem it doesnt recognize the ip address or modem i have tried the reset factory defaults i have tried resseting the modem an i even called comcast

Most Cable Internet Service Providers (ISPs) use Media Access Control (MAC) Address authentication to establish Internet connection for end-users. MAC address is a unique identifier assigned to the network adapter/s of the computer.
To set up your Linksys router to work with a Cable ISP, you have to enable the MAC Clone feature of the router. MAC Cloning is a procedure which enables a router to copy the MAC address of the computer registered with the ISP.
To set up a Linksys router with Cable connection, you need to perform four steps using the computer that's been registered with the ISP:
i. Verifying Internet Connection
ii. Connecting the Devices Together
iii. Checking the Router's LEDs
iv. Setting Up a Linksys Router for Cable Internet Connection

Verifying Internet Connection
Connect the computer to the Broadband modem using an Ethernet cable without the router installed. If you cannot get online, contact your ISP. If it's online, use the computer to set up the router.
NOTE: Some cable modems use the USB port. If the physical connection is via USB port, you may not be able to go online via Ethernet connection. Contact your ISP to have the Ethernet port of the modem configured.

NOTE: The image may vary depending on the computer and modem you're using.
Connecting the Devices Together
After confirming the Internet connection through the modem, connect the modem to the Internet port of the router; connect the computer to any of the four Ethernet ports at the back of the router. For instructions, click here.
Checking the Router's LEDs
After connecting the devices together, check the lights on the front panel of the router. Ensure that the Internet light, as well as numbered light corresponding to the Ethernet port where the computer is connected, is lit. For further instructions, click here.
Setting Up a Linksys Router for Cable Internet Connection

Step 1:
Access the router's web-based setup page. For instructions, click here.

NOTE: If you are using a Mac computer to access the router's web-based setup page, click here.

Step 2:
On the Setup tab, click the MAC Address Clone sub-tab.

Step 3:
Select Enabled then click Clone My PC's MAC.

Step 4:
Click Save Settings.

Step 5:
Click the Status tab.

Step 6:
Check the Internet IP Address. If the Internet IP Address has numbers, this means the router has been properly configured. You should now be able to access the Internet. If you're still unable to access the Internet, powercycle the modem, the router and then restart the computer.

NOTE: If the IP address is still 0.0.0.0, click IP Address Release then, click IP Address Renew. If this does not change the IP Address, powercycle the modem, the router and then restart the computer.

After you have the Ethernet cable from your modem plugged into your PS3 press and hold the reset button on the back of the modem for about 5-10 seconds. This will reset the modem so that it will recognize the connect to your PS3. Once your done using your PS3 and reconnect the Ethernet cable back to your computer you will have to reset the modem again. Any time you move the Ethernet cable from one device to another you need to reset it after you have the cable connected to what ever device you want to get online with at that time. If you do not want to keep resetting your modem all the time a router will allow for you to have more then one device online at a time. The router will connect to your modem and then your devices will connect to your router.

I am not that much clear whether you can change your Ip adress, but any queries regarding Ip-detais can be solved here, http://www.ip-details.com/

if your using a modem its possible that it doesnt have a Ethernet port....Check the back of your modem and you should see a port that says ethernet near it. Plug your ethernet cable to the port in the back of the modem where it says ethernet. With the other end you plug it into the back of your Xbox 360 (its located in back to the far left....it looks like a phone line jack). You should then have xbox live

When the SurfBoard modem is powered up and connects to the internet on the WAN interface, it automatically gets an IP address from your ISP. When another machine is powered up and is connected to the modem via a USB cable, it is automatically using the WAN IP address to communicate with the world. If it is connected via the Ethernet connection, the modem automatically issues it its own IP address for use on the internal network via DHCP. The modem's internal Ethernet connection is 192.168.0.1. The next machine powered on will normally get an IP address of 192.168.0.2.

Make sure your physical connection is correct. From the modem, the ethernet cable should plugged in to the Internet/WAN port of the router. And your computer to port 1. Access the setup page of the router again and Enable the MAC Address Clone setting. Clone the MAC Address of your PC there then power cycle the router and modem. You should be all set.

First i want to know how is your xbox 360 connected to the internet? For example ( Modem Connection?, Router Connection?, Or Wireless Connection?

Here are some steps that you need to try:

1. Turn off your cosole wait for 20 seconds and then turn it back on, then test your xbox live connection

2. Go to your network settings

3. Select restore to factory defaults and test your xbox live connection

is it wireless connection or ethernet? Zoom routers have a firewall and when you have something connected that the firewall doesnt like (Xbox 360 or Gaming) it will drop the connection. goto zoom.com/x6 and it will give you instruction on how to by-pass the firewall using an different IP address.

In order to connect your XBOX 360 to your laptop (if the laptop is connected via dial-up), you'll need a cross-over ethernet cable. It's a special type of ethernet cable, which is typically the same price as a regular ethernet cable, but it allows two devices (in your case) to communicate with each other. Then, you'll need to configure your laptop to allow incoming connections via your Control Panel -> Internet Connections preferences.

Hope this help!
Robert W.

I think the Ethernet cable needs to run directly to your router/modem, you can't bypass it through a laptop (as far as I know!)