Broadcast television in an IP world

Wed Nov 22 19:04:39 UTC 2017

Of potential interest to NANOG members, a key element of the new digital TV OTA standard, ATSC 3.0 (besides improved efficiency/flexibility of modulation, 4K, HEVC video coding, AC-4 immersive audio, high dynamic range/wide color gamut), is the expectation that it will be typically be viewed on an Internet connected TV, thus allowing for a composition of OTA content with interactive & personalized Internet-delivered services.

This hybrid OTA/OTT concept has already been trialed in parts of Europe using the “HbbTV” (hybrid broadband-broadcast TV) standard.  This URL describes some of the potential capabilities of ATSC 3.0 in this area:

https://nabpilot.org/next-generation-tv-home-gateway/

ATSC 3.0 will be deployed early next year in Phoenix, AZ as a test market, with 10 stations participating, including affiliates of the four largest TV networks.

At the same time, many live local television station broadcasts are already available via OTT.  This can be done either directly by a network & affiliates, such as CBS All Access, or through a distributor (which we call a Digital MVPD or “DMVPD”) which now include Sling TV, Playstation Vue, DirecTV Now, YouTube TV, Hulu with Live TV, and Fubo TV.

To aid in achieving the scale required for mass OTT, I’d like to point out two efforts by the Streaming Video Alliance.  The first is the Open Caching initiative.  As you may know, some large OTT content distributors have offered to deploy content caches in end-user ISPs (such as Google Global Cache or Netflix Open Connect), but to date they have been proprietary to that distributor.  Open Caching from the SVA establishes the basic architectural guidelines for implementation of a non-proprietary, open caching system:

https://www.streamingvideoalliance.org/technical-work/working-groups/open-caching/

Another effort is Multicast ABR. This is generally imagined as the use of multicast within an end-user ISP.  There was recently a PoC to demonstrate live 4K streaming using the CableLabs Multicast ABR architecture based on RFC 5740 NORM (NACK-Oriented Reliable Multicast).  This utilizes the home gateway to receive the live multicast stream, and “convert” the stream to unicast HTTP for last-foot delivery.

https://www.streamingvideoalliance.org/2017/07/31/multicast-abr-poc/
https://apps.cablelabs.com/specification/ip-multicast-adaptive-bit-rate-architecture-technical-report

-Thomas

--
Thomas Edwards
FOX Networks Engineering & Operations
VP Engineering & Development
thomas.edwards at fox.com
10201 W Pico Blvd
Los Angeles, CA 90035