Networked media in the facility - Part 1

Much of the conversation and presentations on Tuesday were devoted to the networked facility. Jan Eveleens, CEO of Axon in the Netherlands, discussed the IEEE Ethernet AVB (Audio Video Bridging) technology and standards. More specifically, Eveleens promoted the benefits of an AVB Network. "Ethernet AVB is based on existing and open standards from IEEE," he says. "It’s one framework for reliable, time-synchronized, real-time transport of video/audio/data. It’s proven technology that’s out there now. With the AVnu alliance (which is growing 20+ percent a year), interoperability will be there as well. It’s plug-and-play (no IP addresses); it’s foolproof (the network is self-managing and doesn’t require engineers) and it can co-exist with other networks." How real is AVB? According to Eveleens, standrds are finished and published. "Ethernet AVB switches are shipping and several AVB Pro Audio products are on the market from multiple vendors," he says. "And the first broadcast quality AVB video products have started shipping."

IP Networks in live broadcasts was addressed by Grass Valley's Ken Buttle and Sony Corporations's Toshiaki Kojima. Buttles ticked off the reasons to evolve to a packet-switched networks rather than deterministic for live-broadcast: Physical simplicity, flexibility, commoditization and scalability. "Many of the needs for real-time IP media streaming are already here," he says. But much still remains to be done. Buttles named some of them, including gateways between SDI and IP realms, definition of latency levels with respect to real-time requirements; bridges between media processing equipment across the latency levels; and interchangeable protocols at OSI layers 3 and up Kojima examined a practical approach to IP live production. "Why apply IP to live production now?" he asked. "IP Is not a new technology. Live production may be the last challenge for IP because it requires real-time operations with minimum latency, synchronous processing and video stream switching without picture disruption. Technology improvements are now resolving these challenges, with a rapid increase of available network bandwidth and other factors."

He advised that "the current operational practice should not be changed." "Use existing and emerging standards wherever possible," he said. "Use standard IT-Technology, especially generic Ethernet switches. In order to maximize the benefits, use only functions supported. Network synchronization should be able to achiever sub-microsecond accuracy since it is required over the IP network for some applications such as clean video switching." Nevion USA's senior solutions architect Dr. Chen Chye Koh spoke about IP's adoption for content contribution and production, which has been more difficult than IP's adoption for content distribution. The bandwidth needed to carry high-quality content seems incompatible with "today's need for real-time, no-downtime content transport." Koh asked how to increase and accelerate acceptance. His answer was to increase reliability (protect the content and monitor it in real-time), increase familiarity (consider production requirements, timing synchronization, clean switching and visual monitoring and push button connections and salvos), and lastly and most important, to consider a hybrid network. Koh discussed practical methods of protecting media over IP, looking at Encoder Partner Protection (EPP), cross-strap master and slave with Ethernet connection and RTP synchronization.