On Mon, Feb 11, 2013 at 10:05 PM, Tim Durack <tdurack@gmail.com> wrote:
Multicast is dead. Feel free to disagree. :-)
Tim:>
I really wish I could agree! It would have saved me some time dealing with it. There is the argument of alternative bit rates, compression, etc., but HD streams are assumed[1] at 15 Mbps. At 100Gbps, I can do max 6826 streams of HD streaming. Multicast deployments laugh at this pathetically low number of viewers. At an upstream aggregation point, I can easily serve ~128K subs (7 slots, 8 ports per slot, 3 ports per $ACCESS, 8K[3] users per $ACCESS, 1 slot for upstream). I now assume 2.5 STBs per sub[2]. This results in, more or less, 320,000 STBs. To me, the math says its not dead and we'll need a couple of orders of magnitude (to accommodate the core) in speed improvements to get the same delivery unicast. [1] http://www.cablelabs.com/specifications/OC-SP-CEP3.0-I04-121210.pdf Lists 15Mbps as safe harbor value for HD [2] http://www.aceee.org/files/proceedings/2012/data/papers/0193-000294.pdf Has some stat (good or bad) wrt STBs/household [3] uBR10K (my $ACCESS comparison) specs out for max 64K CPE. One of my guys indicates to me that the actual number might be closer to 15-25K CPE on a given node. Please make adjustments as necessary. (required note: employer is Cisco. Views are my own.) -- William McCall