Production and broadcast facilities continue their adaptation to the semi-seamless integration of file-based workflows. With the dependency on videotape reducing, interchange and archive may remain the last holdouts for tape; but that too is diminishing as requirements for conventional videotape transports dwindle. Collaborative workflow changes are driving the production chain toward a unified high-speed, high-bandwidth infrastructure based on IT platforms. And with it comes new and different challenges.
Besides the impact on videotape, the interchange transport between production subsystems is losing its dependence on coaxial cabling. Files are exchanged between devices on networks over Unshielded Twisted Pair copper wires or via fiber-optic media. Coaxial cable remains geared for real-time live transport of baseband digital data over standard interfaces (i.e., SMPTE 259M and SMPTE 292M), but coax has less value in the file-based domain. Coaxial cable interfaces placed finite constraints on bandwidth, bit-rates and distance. The advent of nonlinear editors, servers and the like have back burned finite bandwidth platforms, forcing the move to an all network-based exchange and accelerating advances in the file-based toolsets.
TRANSPORT CHANGES OVER TIME
At the dawn of disk-based video storage the principle means for moving video between production systems was through real-time play-out over coax to switchers, DVEs and other recording transports (videotape and disk)—much of which remains today. Computer graphics, one of the first platforms to deliver frame-based elements to disk drives, converted data to Y-U-V images for recording as baseband video frames. Play-out to tape was in real time; however, the transport of the image data could be at any rate, dependent upon the devices that created and transported those files. Network architectures were a distant blip on the radar screen at that time.
Fast forward to the new millennium where dozens of file formats are now wrapped and transported for interchange between data storage devices, production systems and contribution networks. Now the environment depending on a network for the success of its operations and less on the generic transport of video through video-routers and over coaxial cable.
Operationally, we now look at network traffic management for the efficient transport of files and for the metering of data interchanges between devices. As a growing requirement at the system level, new toolsets allow the facility better control of the overall system through its network, which in turn manages how these services will carry its data. Early file-based exchanges could easily connect on simplified flat networks tailored only to localized needs. Such examples included point-to-point connections between one video server platform and another, growing to FTP-based file transfers between devices and eventually to geographically separated entities.
Soon more processes lead to more data being exchanged, more connections to be made, and the need to segment traffic into sections based upon operational requirements emerged. The local media network was born, soon followed by requirements for fatter pipes, more security and better connections. Today, architectures must be optimized for highly responsive real-time interchanges of files using a multitude of codecs. Both SD and HD native structures supporting P2 and XDCAM in formats such as XDCAM-HD, AVC-Intraframe, Avid DNxHD (VC-3) and even HDV must all coexist on the same network.
A GROWING CONCERN
Server technologies are the enablers of content interchange for media and entertainment, including production and broadcasters. By definition, a server (when part of a client/server architecture) is that application or a device that performs certain services for those connected clients. Server components may be integrated into the transport device, as part of the broadcast or news server, or incorporated into media caches that perform transcoding and wrapping tasks. Regardless of its actual location, the server remains the element that stores, manages and provides services to the network and its associated peripherals.
On the other side of the equation is the network whose success is in its ability to securely and efficiently move its content around the overall system. Managing these sets of subsystems, especially for media content, is becoming a growing industry concern. No longer does a flat network appeal to even the smallest of facilities. Segmenting systems into VLANs (virtual networks) was once a viable solution, but they failed to control the traffic during peak times or to make beneficial use of high throughput devices during slower periods of the day. So, what we’re finding, which was more evident at NAB this year than in the past, are companies that build toolsets to handle the growing issues of managing digital media at the enterprise level.
(click thumbnail)Fig. 1 shows a data and a management layer, with agents that control, meter and report to the core.Enter the world of “digital media management.” A relatively new term or at least now with a different connotation, DMM describes the processes and manipulation of both the network and the facility data workflow to mitigate bottle necks, improve delivery throughput through acceleration and reduce latency. Beyond just getting the files to the proper systems, DMM also uses agents that report, manage, track and control edge elements while monitoring security, access, certified delivery, automation and usage. The central management “core” then allows the network manager to adjust parameters throughout the workflow process and throughout the network (see Fig. 1).
WHAT DMM CAN DO
A DMM system may be employed locally, i.e., within the boundaries of the facility, or it may be deployed globally for the exchange and transport of data between geographic locations worldwide (distant users). This technology is becoming more important as work collaboration forces the interchange of files across the room or across the continent. Driven by increased requirements for legal approvals prior to air, consolidated processing and preparation of content from a central location and minimizing requirements for travel between locations—file-based infrastructures need this DMM layer.
DMM can also reduce media asset transport and interchange costs. Once the leading inhibitor for centralized operations for broadcasters, the long line carrier charges made it difficult to justify interconnecting facilities over DS3—this is in part because they had little control of the quality of service, but also because users couldn’t realize the full potential of the bandwidth because of other uncontrollable restrictions.
As IP-based telecommunications matures those “best-effort” management principles will no longer be sufficient to sustain business services, regardless of how high the bit-rate may be. Slow file transfers result in business delays and lost productivity. Employing a DMM solution will reduce the numerous network and storage constraints that heretofore have limited the speed, reliability and scalability of current content delivery systems. DMM is a viable solution as network traffic and dependency on files escalates—replacing inflexible legacy FTP-based solutions.
DMM solutions are available for direct integration with video server and other storage platforms, or as suites of modules that are layered into the overall facility on a needs basis. DMM packages can be used for in-house local storage and workflow management, or as interconnect applications that accelerate the WAN on a global scale. Expect to see a lot more of this activity in the coming years as file-based workflows become mainstream in the industry.
