[opendtv] Re: Punching Above Its Weight, Upstart Netflix Pokes at HBO - NYTimes.com

  • From: Craig Birkmaier <craig@xxxxxxxxxxxxx>
  • To: "opendtv@xxxxxxxxxxxxx" <opendtv@xxxxxxxxxxxxx>
  • Date: Mon, 24 Feb 2014 09:38:10 -0500

On Feb 23, 2014, at 6:47 PM, "Manfredi, Albert E" 
<albert.e.manfredi@xxxxxxxxxx> wrote:
> I guess to put it more succinctly, I would not expect a new VOD source to 
> require more network bandwidth? VOD is by its nature a one-to-one 
> proposition. A subscriber is unlikely to be watching more simultaneous VOD 
> streams, just because a new VOD option is added.
> I would expect more VOD to involve more server capacity. Not sure what you 
> mean by "The video asset it trucked from the VOD farm (where the assets are 
> stored) to the pumps sites, ..." Are these "pumps sites" edge storage?

Not in the Internet sense. Most cable VOD is delivered over the QAM portion of 
the plant. Because of this bandwidth on the customer node can be an issue, if 
too many homes on that node request a VOD event. Remember, most of the system 
bandwidth is used to deliver hundreds of live channels, and much of the rest is 
now used for ISP service.

Traditionally the big Cable MSOs have centralized the creation of the streams 
that are delivered as VOD. Depending on how they get an asset, they may need to 
encode it using MPEG-2, after inserting any pre/post roll ads or promos, and in 
some cases ads within the program. These encoded asserts are then sent yo each 
head end and loaded on the playout servers. I believe Jim was talking about the 
use of the Internet to move finished assets from the centralized servers to the 
playout servers at the head ends. 

In listening to the Comcast rep on the Streaming Media panel, it sounds like 
they made the decision in 2008 to start moving their VOD services to IP 
delivery. They have six regional hubs where IP streams are hosted - it was not 
clear from his presentation if they are adding edge servers in each market, but 
this would clearly make sense as more traffic moves from the "live" QAM side of 
the plant to IP VOD side.

> For a service like this hypothetical Netflix-to-in-home-TWC-STB, I would 
> expect it would be entirely VOD regardless. The Netflix scheme doesn't 
> include live streams, right? So they wouldn't be using the "live video" 
> bandwidth, aka MPEG-2 TS broadcast streams, *unless* TWC only offers VOD by 
> means of in-home PVRs. I doubt they do that.

They offer VOD as on demand QAM streams. They are highly constrained with 
respect to the number of titles available and they typically cannot insert 
commercials dynamically into these VOD streams, as they are pre produced at the 
central location.

> So, whatever bandwidth TWC uses for their own existing VOD service is the 
> same bandwidth a Netflix VOD service would use.

No. They are currently on different sides of the plant.

> I assume that even the legacy TWC VOD service is provided by servers at the 
> edges of their walled garden network (don't know if it uses IP or other).


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