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VLAN IDs for DOCSIS cable modems

Can somebody point us at the right direction, documentation about VLAN IDs for DOCSIS cable modems? How should the config files be done, how to configure the CMTS, the switch, the router, the host etc? We have uBR 924 cable modems.

We want to be able to separate broadcast domains for different group of customers, L2VPN services etc.

Any help appreciated,



Re: VLAN IDs for DOCSIS cable modems

The 802.1Q TLS feature provides the means to create L2VPNs between multiple sites, similar to the Private Leased Lines, Frame Relay, ISDN, ATM, SMDS, and the like that are offered by the Telcos.

In many cases, TLS can be viewed as a Frame-Relay-like service. It can accommodate many traffic patterns, such as point-to-point, point-to-multipoint, or fully meshed.

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Re: VLAN IDs for DOCSIS cable modems

We have read somewhere there are three ways you can what we want to do (separate the users broadcast domains, offer L2VPNs etc):

- by maping the cable modem?s MAC address to an VLAN, so that all the traffic from that CM gets tagged by that VLAN?s ID;

- assaigning an modem to an VLAN with the settings on it?s configuration file and

- by tagging the frames at the CPE level.

Does anybody have experience on this, can this be done on Cisco CMTSs and/or CMs? If yes, how?

Any help appreciated,


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