Video Over IP: Bright New Future Or Pandora's Box?

Broadcast television is all about timing, says Kevin Salvidge. Terrestrial and satellite programmes still have to be played out on schedule even though internet-based second-screen and catch-up services are free from the dictates of the clock.

Most critical of all is the timing of the actual video signals and any transitions. So it is ironic that the brave new world of IP based delivery is beset with timing issues.

SMPTE-2110 is the crucial reference for broadcasters keen to make the most of the consumer-off-the-shelf IP technology that heralds this brave new dawn. The first video-over-IP deployments have followed the broadcast industry's tried-and-trusted method of applying this new technology with a familiar existing workflow.

When file-based content management was first introduced, manufacturers extolled the benefits of collaborative workflow which allowed pre-transmission operations to be carried out in parallel rather than sequentially. Many broadcasters replicated the linear workflows and retained them for many years before finally enjoying the full benefits of file-based parallel working.

Video-over-IP is following the same well worn path. The initial video-over-IP deployments are using the SMPTE-2022 standards that have simply replicated the SDI movement of video but have this time replaced coaxial cable with Ethernet cables and round BNC connectors with square RJ-45 connectors. Let us not knock these pioneers; without their visionary approach, the industry would not be where it is today.

The real benefit of video-over-IP comes in the next standard: SMPTE-2110. Having proved that we can move broadcast-quality uncompressed video across IP networks, we can now exploit the benefits of processing the video, audio and ancillary data separately and at different locations, before the signals are re-united and placed in the delivery chain.

SMPTE-2110/10/20/30 with VSF-TR04 forms the backbone of this revolutionary step, at least in the IP world. VSF-TR03 is the timing portion that SMPTE-2110/30 & 50 is based on. This combination has the unenviable task of trying to unify several well established and widely deployed standards.

For those of us old enough to remember analogue video, the audio was always separate from the video and lip-sync timing errors were the bane of every broadcast technician's life. Embedding audio with the video solved the majority of lip-sync errors and reduced the amount of cable that had to be ducted around a broadcast facility.

SMPTE-2110/40 is where the development gets really interesting. Instead of broadcasting all the ancillary date for every frame, some very innovative algorithms have been developed to increase bandwidth efficiencies and only broadcast the essential ancillary data.

So the future looks bright, all these workflow efficiencies and the benefits of cost savings too. What could possible be holding up this nirvana? Well, remember at the beginning of this article I mentioned how important timing is to the broadcast industry. You guessed it; timing is the big stumbling block in the finalisation of the SMPTE-2110 standard.

Analogue black and burst have been around since the mid 1920s when John Logie Baird and his contemporaries were developing early forms of television. With the advent of high-definition (all things are relative), broadcasters were introduced to tri-level sync.

Meanwhile, the audio brigade who are usually forgotten about until the sound channels go absent without leave, have quietly been moving ahead with audio-over-IP using a precision timing protocol (PTP). That too has an established standard in the shape of IEEE-1588.

The challenge now is to unify all of these timing protocols into a single standard that satisfies all requirements. At this year's annual National Association of Broadcasters convention in Las Vegas, the majority of broadcasters who arrived at the show had draft RFP's for SMPTE-2110 compliant multi-vendor solutions still sitting in their draft folders. That's where we still are with video-over-ip and SMPTE-2110.

Many NAB Show exhibitors ran the now obligatory interoperability demonstrations where multiple vendors, following much consultation, achieved limited interoperability to a draft standard.

Many manufacturers who were early adopters of the SMPTE-2022 standards are now confident that they will be launching SMPTE-2110 qualified products later this year. But will the 10 Gbit/s Ethernet interface they are currently employing be what is eventually used? General consensus within the broadcast industry is that 25 Gbit/s or 40 Gbit/s will be used instead. If they have planned ahead, they will simply need to exchange their SFPs. If the timing piece of this jigsaw cannot be resolved, the true benefits of video-over-IP will remain tantalising just out of reach.

So, what are the alternatives?

Sony has managed to demonstrate an end to end IP based solution with its IP Live (Network Media Interface NMI), but its partner base is nowhere near as large as the AIMs partner list. Sony has in fact joined AIMs and at this year's NAB demonstrated SMPTE-2110-qualified products. Sony’s IP-Live solution offers an end-to-end solution that is deliverable today and also contains the capabilities to be upgraded to support SMPTE-2110 once the standard is ratified.

Some broadcasters have been using the tried and tested SDI to move UHDTV signals around their facilities. This has the benefit of implementing existing SDI infrastructure but it does reduce a facility's capacity as each UHD feed demands four 3G-SDI channels. We are back to analogue video issues, having to ensure the four 3G-SDI signals are exactly in sync with each other.

For those stuck not prepared to gamble on video-over-IP yet, there is 12G-SDI. At last year's NAB show, several manufactures refused to consider 12G-SDI. This led to a number of American outside broadcast companies signing an open letter asking manufacturers not to ignore 12G-SDI.

The request appears to have been heeded as 12G-SDI product announcements did trickle through at this year's NAB. Information on actual product availability and was difficult to obtain. Some manufacturers who have launched 12G-SDI products are now starting to indicate that video-over-IP hybrid operation will be possible when the timing issues relating to SMPTE-2110 are finalised.

A concluding question: Are broadcasters ready for the security issues that video-over-IP brings? Gone are the days of the chief of security being the commissioner standing at the door and keeping unwanted riffraff out of the hallowed halls, or the grumpy gatehouse man trying to keep you out of the car park at Television Centre. If NASA, the Pentagon and the Holiday Inn chain of hotels can be hacked by a teenage loner sitting in his bedroom in London, imagine the potential for cyber attacks from hackers demanding a ransom not to take your channel off the air during your most popular programmes. Don't say it won't happen. France has already experienced such an attack on one of its major broadcasters.

Kevin Salvidge is Managing Director of Hatstands Broadcast and Media Productions Limited.

www.hatstandsbroadcast.com

This article is also available to read in the latest edition of Broadcast Film & Video here, page 29.

(JP/LM)