Print Page
McAdams On: The Role of SDNs in the Virtual Media Facility

QUANTUM, ENTANGLEMENT — The era of the physical facility is rapidly evolving. I won’t use the term “declining” just yet, because ESPN has just built a new 193,000-square-foot facility in Bristol, Conn. This seems to counter a migration toward full virtualization, when the media “facility” as we once knew it becomes a tightly managed streams of electrons.

At the heart of this migration, I’m told, is the software-defined network. The SDN, as opposed to the current packet-switched network, is basically a “smart” infrastructure that can self-adjust to bandwidth demands. A software-defined network can configure and reconfigure itself, while packet-switched networks require manual intervention.

The present environment is one where the network switches are tightly coupled to their internal control systems,” said Clyde Smith, senior vice president of New Technology at the Fox Network Center. “To provision a service that needs multiple protocols across many ports and through many individual switches is a very manual process where the operator configures the system, switch by switch. This means we need many staff members working in concert to rapidly provision or make changes.”

Whereas, with an SDN, “network topography and configuration can be constructed and ready for deployment in less than 15 minutes,” according to a white paper from Alcatel-Lucent.

Larry Kaplan goes deeper. Kaplan is founder of Software Defined Video Infrastructure, or SDVI Corp., a virtual media infrastructure startup in Menlo Park, Calif.

“The essence of a software-defined network is control and configuration of each data path in the IP network by an external application,” said Kaplan, who cofounded Omneon, which is now a part of Harmonic. “Today, this control and configuration is buried in the IP switch firmware. The SDN approach has very significant benefits including 1) extremely fast network reconfiguration on a path-by-path basis, so I could set up a 4K redundant path in near real time with something that looks like an Apple app.”

Further, Kaplan said, SDNs are basically data agnostic, so moving to higher resolution content such as HD to 4K to 8K and whatever comes after that, is a matter of using the network configuration app, for example.

What this all boils down to isn’t so much the end of the physical facility, though that is a potential outcome in theory. Certainly, the physical footprint can be reduced dramatically through virtualization. (Think of virtual set. There still has to be a place to hang the green screen.)

The greater promise of media facility virtualization is the ability not only to reconfigure networks on the fly, but to do so with cognitive automation that anticipates whatever new device, display size, flavor of operating system and distribution mode comes down the pike. The hundreds of new viewing platforms that cropped up in just the last few years alone have made content distribution more bespoke than prêt-à-porter, and media facilities already are challenged to meet the demand.

Fox’s Smith says the switch-based network infrastructure “simply will not scale in the future, and even worse, try to extend this model to remote private clouds—how many VLANs can you manage?—and in public clouds, it will not work at all.”

Antonio Liotta, professor of network engineering at the Eindhoven University of Technology in the Netherlands, makes a similar observation about the packet-switched infrastructure beyond the media facility.

“It’s already struggling to cope with the data being generated by ever-more-popular online activities, including video streaming, voice conferencing, and social gaming,” Liotta wrote in IEEE Spectrum. “Major Internet service providers around the world are now reporting global latencies greater than 120 milli­seconds, which is about as much as a VoIP connection can handle. Just imagine how slowly traffic would move if console gamers and cable television ­watchers, who now consume hundreds of exabytes of data off-line, suddenly migrated to cloud-based services.”

Within media facilities, the data explosion is being propelled by the demand for content to be delivered anytime anywhere, on anything. Nearly every screen type requires a level of customized data such that programs, which are actually files, each trail mini-files—in the form of metadata—like meteor dust. This file proliferation puts ever greater demands on networks that weren’t designed with such demands in mind.

E.g., one hour of uncompressed HD video is about 4.4  GB. An average “library” has between 1,000 to 2,000 such files, according to my server guy. Each of these files are made of “dozens to hundreds” of video and audio elements, each with metadata describing  what it is, who shot it, where it goes in the edit sequence and so forth. Still more metadata describes the file size, type, format, length, where it’s stored, when it was created, when it was modified, etc. Further metadata is associated with rights management, scheduling, sales and tracking, for example. Different systems manage these different types of metadata, though not always in tandem, in which case, the library is closed.

Here’s Lieven Vermaele co-founder and CEO of SDNsquare, an IP-networking startup in Gent, Belgium. “I always had one problem when I worked in the media industry with VRT and then the EBU—routing was never optimal for media, and networks go down,” he told TVBEurope after IBC this year. “In the post environment, we had bigger files going round and the traditional answer of the industry was always over-provision. We have to get the jams away from media networks, and that is what we have done with the software-defined network.”

The question now revolves around the migration path from hardware and packet-switched networks to virtual machines and SDNs. The TV industry is almost universally dependent on SDI video over coax, which in turn is largely dependent on purpose-built hardware, my server guy tells me.

“Yet once you move away from SDI—which seems to be gradual but continuous—then you have no choice but to put this on a network,” he said. “Then, the ability to reconfigure a service, operation or subsystem rapidly in order to address the dynamics of a changing business need, policy or even ownership change… it should become much easier to do if you let SDN handle this instead of having to call the IT guy and remap a network from the physical layer standpoint.”

Virtualization. The next great Digital Transition.
  Print Page