nanog mailing list archives
Re: DOCSIS 3.0 and Multicast
From: Scott Helms <khelms () zcorum com>
Date: Fri, 29 Nov 2013 09:58:30 -0500
Keep in mind that in the cable world the node itself is a layer 1 device, basically it converts between fiber and coax signaling, and so it doesn't take part in any IP transactions. Now, if your CMTS supports multicast and the modems on the same node are on the same downstream AND multicast is enabled on the CMTS then the devices behind the modem (which is a bridge) can use the same stream. A device behind the modem could actually be an embedded device on the modem, but in the DOCSIS world the modem itself (usually) has its own MAC address and each integrated device will have its own so a home gateway product (video, MOCA, voice, router, and WIFI) will often have 5+ MAC addresses, one for each of the devices and often each one has its own configuration. This tutorial may help some: http://www.nanog.org/meetings/nanog48/presentations/Sunday/Riddel_VDOC_N48.pdf Scott Helms Vice President of Technology ZCorum (678) 507-5000 -------------------------------- http://twitter.com/kscotthelms -------------------------------- On Fri, Nov 29, 2013 at 9:32 AM, mr. s <sigasecure () gmail com> wrote:
To Those Who Do DOCSIS3.0, I can't seem to find a simple answer to this, possibly because it is self evident to those actually using Multicast over DOCSIS. Which we are not currently. Multicast over DOCSIS 3.0, to 3.0 CM, can the CM share the same media stream on their node? In example, 2 Cable Modems in the same node (no splitting, same US/DS channels/ports, CMTS..), each have a customer watching ESPN. Is there one or two media streams worth of content on the plant, channels, node? We now how this operates in other worlds, GPON, xDSL and AE. Just haven't seen it specifically mentioned out right in DOCSIS literature. Thanks for any direction you have.
Current thread:
- DOCSIS 3.0 and Multicast mr. s (Nov 29)
- Re: DOCSIS 3.0 and Multicast Scott Helms (Nov 29)
- Re: DOCSIS 3.0 and Multicast Phil Bedard (Nov 29)
- Re: DOCSIS 3.0 and Multicast Phil Karn (Nov 29)
- RE: DOCSIS 3.0 and Multicast Frank Bulk (Nov 29)
- Re: DOCSIS 3.0 and Multicast Phil Karn (Nov 29)
- Re: DOCSIS 3.0 and Multicast Scott Helms (Nov 29)
- Re: DOCSIS 3.0 and Multicast Phil Karn (Nov 29)
- Re: DOCSIS 3.0 and Multicast Jay Ashworth (Nov 29)
- Re: DOCSIS 3.0 and Multicast Phil Karn (Nov 29)
- Re: DOCSIS 3.0 and Multicast Phil Karn (Nov 29)
- Re: DOCSIS 3.0 and Multicast Victor Kuarsingh (Nov 29)