Cable Modem Install

Perryg114

Senior member
Jan 22, 2001
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If I remember correctly you have to register the modem with the internet provider by giving them the MAC address of the modem. I also remember having to set up the router so that it spoofed the MAC address of the NIC that my PC had in it when the modem was originally setup. Is this last step not required anymore? I am having trouble with my Mediacom internet. They are not at all helpful.

Perry
 

Perryg114

Senior member
Jan 22, 2001
768
4
81
So how do I tell the modem what the router MAC address is? The modem instructions mention nothing about modem to router/Nic communication.


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Fardringle

Diamond Member
Oct 23, 2000
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The router tells the modem what the router's MAC address is. You shouldn't have to spoof the address there unless you are replacing the router as well and your ISP only allows a connection from a specific MAC address (some do, but most don't any more). If you are replacing the router and need to spoof the MAC address, you will do that on the configuration page of the router.
 

boomhower

Diamond Member
Sep 13, 2007
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I've changed the router out on mine without any issues. TWC internet FWIW.
 

Cabletek

Member
Sep 30, 2011
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If I remember correctly you have to register the modem with the internet provider by giving them the MAC address of the modem. I also remember having to set up the router so that it spoofed the MAC address of the NIC that my PC had in it when the modem was originally setup. Is this last step not required anymore? I am having trouble with my Mediacom internet. They are not at all helpful.

Perry

You give the mac and the model information so they can send a BOOT file and config file for that modem, and provision it to their cmts.


I do not understand why spoofing a mac is needed and fear this stems from more confusion. The modem will remember the first mac is connects with and not talk to another one unless you reset it by simply pulling the power plug out and putting it back in with a new device connected. Spoofing a mac is a round about way of beating that, but its really not that hard to just power cycle the device.
 

Fardringle

Diamond Member
Oct 23, 2000
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Some ISPs still only allow connections from specific authorized MAC addresses. In those cases, you have to spoof the authorized MAC address to the router in order to establish a connection. Most ISPs don't do it any more, but it's worth trying if other normal troubleshooting steps don't work.
 

ch33zw1z

Lifer
Nov 4, 2004
38,816
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This really varies with provider. When I originally installed Comcast just over ten years ago, the first MAC their system saw was bound to the account, so when you set it up with your PC it locked it in and you then had to spoof your PC's MAC on the router when you set it up.

This is not the case IMXP with Comcast anymore. When I swap out the router, I just make sure to fully power cycle the modem, disconnect power, coax, and ethernet.

So, with Mediacom, it's best to ask. If Level 1 isn't helpful, demand escalation.

What exactly is the problem you're having OP?

If you replace the modem, then you have to provide them with the serial number and a couple other numbers off the back, don't remember what they're called off hand, basically hardware identifiers.
 
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Perryg114

Senior member
Jan 22, 2001
768
4
81
From talking to motorola last night this modem will connect to any MAC address unlike the old one. Problem seems to be with the signals not being right. I probably did not need a new modem but the other one was over 10 yrs old.


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