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Ignitionnet · 07-02-2010, 11:07

No, it's not VLANing really, the closest to that you find on the cable network is frequency division multiplexing. For example My DOCSIS 3 cable modem runs on 4 downstreams, 299, 307, 315, 323MHz. A DOCSIS 1.1 cable modem can go onto any one of those and not share downstream capacity with other DOCSIS 1.1 modems on other channels.

The cable network really isn't that smart, think of an old BNC thicknet and you're about there.

The combining of DOCSIS 3 network over multiple nodes was as much as anything else VM being cheap and wanting to save cash on line cards. You should be mindful of the distinction between physical segmentation, how many homes are connected to a node and therefore on the same physical broadcast domain, and logical segmentation, such as taking the DOCSIS 3 output and splitting it to feed multiple physical nodes.

07-02-2010, 11:07	#12
Ignitionnet Inactive Join Date: Jun 2008 Location: Leeds, West Yorkshire Age: 47 Posts: 13,995	Re: Mac address daily limit No, it's not VLANing really, the closest to that you find on the cable network is frequency division multiplexing. For example My DOCSIS 3 cable modem runs on 4 downstreams, 299, 307, 315, 323MHz. A DOCSIS 1.1 cable modem can go onto any one of those and not share downstream capacity with other DOCSIS 1.1 modems on other channels. The cable network really isn't that smart, think of an old BNC thicknet and you're about there. The combining of DOCSIS 3 network over multiple nodes was as much as anything else VM being cheap and wanting to save cash on line cards. You should be mindful of the distinction between physical segmentation, how many homes are connected to a node and therefore on the same physical broadcast domain, and logical segmentation, such as taking the DOCSIS 3 output and splitting it to feed multiple physical nodes.