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Is a DOCSIS modem only authenticated by the CMTS by a MAC address or are there any other AAA techniques? In that case, how do I prevent other customers from spoofing my modem's MAC address?

  • Cable Modem Initialization Wallchart published by Cisco in 2005:


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up vote 0 down vote accepted

MAC address spoofing is possible, but a) requires knowledge of existing, valid, not used MAC address b) tools - not that widely available for cable modems as for ethernet routers.

Certificate based authentication and encryption is available (Baseline Privacy Inteface Plus - DOCSIS 1.1 and DOCSIS 2.0, Security in DOCSIS 3.0) - see for some more details.

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