PRINCETON, N.J.—Mark Corl, Triveni Digital’s senior vice president of emergent technology development, will take part in a panel discussion on NextGen TV interactivity during the ATSC 3.0 Summit taking place during Future’s Tech Leadership Series. Corl will use his experience of developing ATSC 1.0 and 3.0 solutions to discuss ATSC 3.0’s hybrid broadcast and IP architecture.

"With ATSC 3.0, broadcasters have the power to take traditional linear viewing to engaging new levels," said Corl. "At the Summit, I'll discuss the interactive layer of ATSC 3.0, which leverages the connection between broadcast and broadband to enhance the user experience, enabling personalized content delivery and increased revenue opportunities for broadcasters."

Joining Corl on the panel will be Greg Jarvis, executive vice president and general manager at Fincons, and Richard Glosser, head of business development at Verance.

With technical deployments of NextGen TV scaling rapidly across the country, the opportunity to define breakthrough products/services and prioritize viable go-to-market business models is timely and tangible, and this ATSC 3.0 Summit will be a conversation center for all of it.

The ATSC 3.0 Summit panel discussion on Interactivity will take place on March 25 from 3:25-4 p.m. ET. For the full schedule or to register, visit the ATSC 3.0 Summit website. 

Part One 

The IEEE Broadcast Technology Society (BTS) focused its attention on ATSC 3.0 Single Frequency Networks and virtualization during four sessions that kicked off its IEEE BTS Pulse online conference.

The session block examined the basics of ATSC 3.0 SFNs, virtualization of 3.0 broadcast gateways, extending the function of 3.0 SFNs by leveraging stream multiplexing to reach transmitter sites and the broadcast core network.

“ATSC 3 Single Frequency Networks and Virtualization,” chaired by Merrill Weiss, consultant and owner of Merrill Weiss Group, also included Benoit Bui Do, technical leader for terrestrial solutions at ENENSYS Technologies; Mark Corl, Triveni Digital senior vice president of Emergent Technology Development; and Ali Dernaika, solution architect at HPE America, addresses gateways, stream multiplexing and the core network, respectively. The session block was moderated by Joel Walsh, director of Education at SMPTE.

THE FUNDAMENTALS 

Weiss kicked off the event by examining the fundamentals of ATSC 3.0 and how SFNs can be used, including an explanation of the 3.0 physical layer, framing and the bootstrap, as well as several 3.0 SFN-related technologies and techniques.

Weiss then explained how the transmission characteristics of 3.0 are “about the best there are in the world in terms of the range and the proximity” to the Shannon limit—the theoretical maximum error-free data throughput for a given amount of noise on a channel.

Next he reviewed 3.0 Physical Layer Pipes, which are “essentially combinations of a number of carriers,” and times in a 3.0 subframe. “So, every one of these intersections of frequency and time, you can think of as a cell … [that] carries a certain amount of information,” he said.

The cells can be organized in different ways, enabling frequency division multiplexing, time division multiplexing, a combination of frequency and time division multiplexing and layered division multiplexing (LDM). Putting different levels of power into different layers makes it possible for LDM layers to have their own modulation encoding.

“Depending on how you choose to set the modulation encoding, you can have more or less robustness and more or less data capacity,” he said.

Weiss then discussed data sources entering a 3.0 system via the “Data Source Protocol,” which are packed into ATSC 3 Link Layer Packets (ALP) and transferred to the Broadcast Gateway where the Scheduler packs the ALP packets into PLPs. This ensures packets use available PLP space efficiently, he said.

Three transport protocols are used to get data to the transmitter—DSTP, ALPTP and STLTP (Studio-to-Transmitter Link Transport Protocol)—to enable data to be transferred between layers and guard against what’s known as “layer violations,” said Weiss. In the case of DSTP and ALPTP, this is accomplished with information available in an information header that precedes the packet. For the STLTP, this is done with an RTP (Real-time Transfer Protocol) header.

All of these protocols provide for tunneling, which enables a number of multiplex streams to be carried inside another stream. In the case of ATSC 3’s studio-to-transmitter link, there can be up to 67 different streams, all of which are treated as one stream as part of the common tunneling protocol (CTP), he said.

CTP provides for additional services like forward-error correction and security to prevent “man-in-the-middle” attacks, similar to the “Captain Midnight” attack on HBO’s delivery of its signal to cable headends several decades ago, he added. ATSC 3.0 provides for authentication and encryption to guard against such attacks.

Two types of time are provided for in ATSC 3.0. For upstream of the broadcast gateway, UTC (Coordinated Universal Time) is used. Atomic time also is used for synchronization of time and frequency and as a parameter in the security system, Weiss explained.

Having discussed 3.0 fundamentals, Weiss turned to SFNs, which consist of multiple transmitters delivering the same signal on the same frequency to a given service area. “In order to do that,” Weiss said, “the frequencies have to be matched and the emission times have to be precisely adjusted.”

All transmitters must have the same reference bootstrap emission time, but they may be offset to shape network signal delivery, he added.

Weis also examined one way to localize datacasting in an SFN. It involves having a “normal” SFN deliver “mostly the same data on the same frequency into the overall service area but to allow certain PLPs to carry different data.” 

These specific PLPs are the same for every transmitter to ensure they transmit during the same transmission period to specific areas. Because different data is placed on different cells during given PLP periods and on the same PLP frequency, the cells will interfere with one another where coverage from SFN sites overlaps, Weiss said. 

“Doing this becomes an exercise in carefully adjusting the properties of the transmission. … [B]y making good choices of what the parameters are, that interference can be minimized, and these smaller service areas can be enlarged to the maximum extent possible [to enable localized data delivery],” he said.

EXTENDING SFN FUNCTIONALITY

Triveni’s Corl examined the use of 3.0 SFNs as a statewide network. For the presentation, Corl looked at a hypothetical network with a broadcast studio—in some cases multiple regionalized studios across the state—connected to a set of transmitters. Some may be connected via microwave, by fiber through a switch and even an SFN at the edge.

“In the ATSC 1 world, that [the described network] wasn’t a problem, but in the ATSC 3 world there’s a lot of signing and authentication going on,” said Corl. “[S]ending the same stream to all the transmitters is somewhat problematic because all that signaling and interactive content and all the things you might want at these different transmitters has to be signed.”

Having private keys “floating around” at the transmitter sites where there may be no one to attend to them isn’t a good idea. “So, you can’t actually regionalize things unless you have multiple STLs—separated all the information out into multiple STLTP streams,” he said.

This would be necessary because at the exciter level it’s not possible to “crack open” the STLTP and “tear things apart or add things,” Corl explained.

Another consideration is that in many statewide networks, especially those of public broadcasters, most of the data is redundant. There are some primary channels and occasionally some tertiary channels, but the broadcaster might want to do region-specific, ancillary text crawls, he said.  

Bandwidth restrictions in the network can be a problem. “Sending a couple—maybe three or four—STLTPs to transmitters over fiber is no big deal … [where] they typically have a gig of bandwidth,” he said. “But when … the connections are only, say, 10BASE-T … you really have to start paying attention to the network’s capabilities.”

Before laying out the statewide SFN network solution in detail, Corl reviewed basic ATSC 3.0 transport concepts, illustrated with a diagram that started on the right with Data Source Packets and ended on the left at the exciter. 

In between was a visual representation of the Common Tunneling Protocol (CTP) and Data Source Transport Protocol packets feeding the ALP Encapsulator. The CTP uses SMPTE ST 2022, which enables use of forward error correction and a fixed packet size. “They’re all RTP, UDP IP multicast packets, but they are completely opaque to what they are carrying,” said Corl.

One important quality of the DSTP—which carries receiver-destined packets—is that the packet address space is hidden. This is important because it allows duplicate Data Source Packets to be sent without conflicting with one another or needing a receiver to understand there are differences, he explained.

The ALP Encapsulator processes the DSTP packet tunnel and strips out everything and puts the internal packets carried through the tunnel into “out packets,” which are data packets with a particular header that use the ATSC Link Layer Protocol (ALP). This allows the packets to be hidden on the receiver side and in the Scheduler. At this point, ALP Encapsulator maps Data Source Packets to PLPs—one ALPTP to one PLP. The encapsulator then sends ALP packets to the Scheduler, he said.

It, in turn, processes the ALPTP packet tunnel, inserts PLP ALP packets into baseband packets, adds the preamble, timing and management packets and turns them into STLTP packets, which carry the preamble, baseband and time and management packets to the exciter. In each phase, packets are signed, he added.

Corl emphasized that ATSC 3.0 is IP-based, which means the stream doesn’t simply need to be data intended for receivers—audio, video and closed captioning data, but it is also possible to put other data into the stream that’s not intended for regular off-the-shelf receivers, he said.

Corl laid out different scenarios supporting the hypothetical statewide SFN, beginning with in-band distribution to individual SFN transmitter sites. “Essentially what you’re doing is carrying a backhaul for the SFN,” he said. “You’re carrying the STLTP in the actual broadcast.”

The STLTP carriage can be in a separate PLP. LDM may be used, announced as a private data stream in the low level signaling (LLS). A dedicated antenna tuned to receive this signal from the source transmitter is used. This setup also provides a redundancy mechanism if the network is lost. “The exciter doesn't actually have to be connected to a network or as well, it can be connected to the network and actually see this other STLTP carriage as a backup,” he explained.

The second scenario leverages regionalized PLPs. Here ALPTP is sent over the broadcast with common AV services, such as SD and HD, and some NRT (non-real time) data carrying configuration data. There is also a regional AV service in a secondary PLP. Receivers in the broadcast coverage area won’t know what to do with the secondary streams and ignore it.

At the SFN receive site, the configuration data will be used to program two functions that “essentially are equivalent to a Broadcast Gateway,” said Corl. This approach enables ALPTP streams and NRT to be privately signaled and carried in another PLP. Another ALPTP stream could be carried to supply a PLP to remove ALP encapsulation.

A third scenario allows for regionalized PLPs, but focuses on the content. “In each stage … we’re basically taking and carrying different aspects and different control information to the point where we can fine tune it down to the point where we have different signaling for each of the transmitters,” he said, adding that the signal doesn’t need to be signed at the regional SFN transmitter because it was signed at the studio and passed to the SFN transmitters.

“We can actually have very specific transmitters and essentially build an entirely new broadcast at each stage simply by taking very selective IP streams out of the network and carrying this information,” he added.

In all three scenarios, everything coming over the air can be signed and validated to make sure a nefarious actor is not replacing content or changing any of the signaling. Additionally, with physical security in place at SFN sites—locks on transmitter buildings—there is no need for a private key for the entire network at these remote sites. “You just need it to be able to decode whatever’s coming in,” he said.

Finally, Corl laid out a backup plan to reach all SFN sites, which is already in place with the 3.0 SFN deployment. 

“Backup information could be running all of the time, and you could be sending out the information all of the time, even though your networks were there,” he said. “So failure of the network or even partial failure of the network would easily be just switching over to the other mechanisms and carriage.”

(Editor’s note: Part two will examine the Broadcast Gateway and Core Network presentations.)

WASHINGTON—Three industry executives have been elected to the ATSC Board of Directors: Mark Aitken, Mark Corl and Jon Fairhurst. All three will serve three-year terms set to begin in January 2021.

Aitken, vice president of Advanced Technology at Sinclair Broadcast Group, was elected to the board for the first time. Corl, from Triveni Digital, and Fairhurst, from Samsung, were both re-elected.

Also joining the board as the Institute of Electrical and Electronics Engineers’ (IEEE) 2021 ATSC board representative is Dr. Yiyan Wu of the Communications Research Centre.

Craig Todd, who is set to retire from Dolby, will end his time on the board in 2020. As will Wayne Luplow, former ATSC Board chairman and a retired Zenith executive, who most recently represented IEEE on the board.

The new board members will join a group with Lynn Claudy, NAB; Jim DeChant, News-Press & Gazette Company; Richard Friedel, Fox Television Stations; Ira Goldstone, Cobalt Digital; Dr. Jong Kim, LG Electronics; Brian Markwalter, CTA; Anne Schelle, Pearl TV; Andy Scott, NCTA—The Internet and Television Association; Glenn Reitmeier, GlennReitmeierTV LLC; Dave Siegler, SMPTE; and Pete Sockett, Capitol Broadcasting.

On the agenda for the first meeting in 2021 will be the election of a new chairman, as Claudy’s time in the position will conclude in 2020.

“ATSC is fortunate to have Directors who bring a wide range of skills, backgrounds and expertise to the board,” said Madeleine Noland, ATSC president. “I feel privileged to be able to work with this outstanding group of people as we guide the organization forward in 2021, which promises to be a critical year for next-generation broadcasting in the United States and around the world.”

LAS VEGAS—In addition to the setup that it will have at its booth for the 2019 NAB Show, Triveni Digital will share its expertise as part of the Broadcast Engineering and Information Technology Conference at the show. Specifically, company executives Mark Carol, senior vice president of emergent technology development, and Dave Catapano, senior vice president engineering, will be speaking about the interactivity and security requirements of ATSC 3.0.

Corl is scheduled to give two presentations during BEITC. “ATSC 3.0 Interactive AEA Enhancement Toolkit” is the first and gives an overview of the ATSC 3.0 standards in regards to emergency notifications and the aspects of deploying a broadcaster workflow to support it, as well as how broadcasters can use software tools to customize and optimize an AEA enhancement workflow to their environment. This talk will be held April 6 from 3:20-4:40 p.m. in room N260B of the Las Vegas Convention Center.

On April 7, Corl will present “Practical Aspects of ATSC 3.0 Interactive Content Development. In this presentation, Corl will examine the A/344 standard, with a focus on practical aspects of deploying interactive broadcaster applications to ATSC 3.0 receivers. It will also cover the features that the A/344 standard provides and how new platforms can simplify these interfaces via software development kits. This talk will go from 1:50-2:10 p.m. in N256.

Catapano, meanwhile, is giving a talk titled “Requirements and Workflow for Creating a Secure ATSC 3.0 Broadcast.” This session will look into new security requirements involved with creating and transmitting ATSC 3.0 broadcast streams, which require a chain of trust for both core signaling and enhanced content. Catapano’s talk is set for April 6 from 1:30-2:50 in N260D.

At Triveni Digital’s booth, N3908, the company will feature its metadata generation, transport stream analysis, monitoring and troubleshooting systems.

The BEITC will run in conjunction with the 2019 NAB show from April 6-11. To register for the NAB Show, visit www.nabshow.com.

WASHINGTON—Elections for three spots on the ATSC Board of Directors recently took place with the results putting Craig Todd, senior vice president at Dolby Laboratories, Mark Corl, senior vice president at Triveni Digital, and Jon Fairhurst, principal standards engineer for Samsung, on the board for three-year terms.

Corl and Fairhurst are both newly-elected members to the board. Corl works with emergent technology development at Triveni, focusing on new technologies that impact digital TV distribution, specifically IP-delivered content. Corl has previously worked with the ATSC as a chair for two ad hoc groups and served as vice chairman of the Personalization and Interactivity Implementation team. Fairhurst brings more than 30 years of experience working on projects related to digital television, including 10 years at Grass Valley and 20 years at Sharp Laboratories of America. With ATSC, Fairhurst has served as the vice chairman and editor of ATSC Video ad hoc group.

Re-elected to the board, Todd has been involved with the ATSC for 25 years. He served on the board in from 2007-2013 and 2015-2017. He has also been active in other standards and industry organizations, including ITU-R, DVB, UHDA, CTA, MPEG, SMPTE, AES, SCTE, IEC and NABA.

The three newly elected board members will join current board members whose terms continue into 2018: Lynn Claudy, NAB; Richard Friedel, Fox; Dr. Paul J. Hearty, Sony Electronics; Brett Jenkins, Nexstar Media Group; Dr. Jong Kim, LG Electronics; Howard Lukk, SMPTE; Brian Markwalter, CTA; Glenn Reitmeir, NBC Universal; Anne Schelle, Pearl TV; and Andy Scott, NCTA – The Internet and Television Association. In addition, Zenith’s Wayne Luplow has been appointed to the 2018 ATSC board by the Institute of Electrical and Electronics Engineers.

Board members whose terms will expire at the end of 2017 include Christopher Homer, who has retired from PBS; David Siegler, Cox Media Group; and Dr. Yian Wu, Communications Research Center, who represented IEEE for 2017. Friedel’s term as board chairman is also set to expire at the end of 2017; the 2018 chairman will be elected at the first meeting of the new year.

Corl, Fairhurst and Todd’s three-year terms will officially begin in January 2018.

For a comprehensive list of TV Technology’s ATSC 3.0 coverage, see our ATSC3 silo.

PRINCETON, N.J.—The 2017 HPA Tech Retreat is scheduled to host a panel on the interactive layer of ATSC 3.0, which according to a recent press release will be led by Triveni Digital’s Mark Corl, senior vice president of emergent technology development.

Mark Corl

The panel will feature participants discussing how ATSC 3.0 provides an expansive environment for W3C-based interactive content delivered over broadcast or from the internet, as well as how content providers can enhance their offerings for a more engaging and personalized experience for consumers. The panelists will include Guy Hadland, CTO at UniSoft; Azita Manson, president of OpenZNet; Pete Van Peenen, senior consultant for Pearl TV; and Joe Winograd, EVP, CTO and founder of Verance.

Corl, in addition to his work at Triveni Digital, is the chair of the ATSC 3.0 Ad-Hoc Group on Interactive Content (S34-4) and the vice chair of the ATSC Personalization and Interactivity Implementation Team.

The ATSC 3.0 panel is scheduled to take place on Feb. 20 at 2:50 p.m. The 2017 HPA Tech Retreat runs from Feb. 20-24 in Indian Wells, Calif.