Archiving for Asset Management
One of the elements in an end-to-end digital asset management system includes how long-term and near-term storage of media will be handled. As the broadcast facility moves further away from video-only technology toward data management, a more advanced set of tools becomes necessary to effectively and efficiently deal with elements on a networked, video file-based platform.
(click thumbnail)Archive data flow and system managementOne of the background functions the video server has provided is a rather simple approach to asset management--the rudimentary tracking of the content from when it was ingested, through storage and finally to play-out.
The database for tracking these assets was simple. It sometimes either relied on or employed second-level applications, such as facility automation, as the interface between traffic and master control operations. Many different asset management components are available from facility automation vendors, but when it came to managing the long-term offline or secondary storage, the archive manager application became the interface between servers and secondary storage of all formats.
The key to the end-to-end digital asset management system is its database. Since traditional databases have seldom been suitable for managing video content, there's been a need for an application that goes beyond the fundamentals of the facility automation system or the video server's internal database. This application is generally described as the "digital- or media-asset manager" (DAM or MAM), and by its very definition, it can be both specific and ambiguous. This installment will not attempt to deal with this broad definition, but instead will focus on one of the operational segments of the overall solution--the archive.
ARCHIVE MANAGER
The component of an asset management process aimed at handling long-term and short-term lookup, file movement, storage management and archiving is referred to as the "archive manager." Archive systems, which are made up of software, servers and control interfaces, help to support the easy transport of assets between and among storage and server subsystems. The archive system is in turn leveraged so that multiple uses may be achieved by multiple users.
Digital media assets can be comprised of unstructured and unconnected content--video, audio, images and text. As such, the archive system will be expected to interface with a large set of existing and anticipated station subsystems. These include station automation systems, video servers and archive peripheral storage devices--whether optical or magnetic disk, or linear digital tape. For the broadcaster, the archive solution must directly interface with asset management components and with delivery platforms that extend beyond the domain of real-time video and audio content distribution.
Today, material may be stored in video servers, intermediary RAID cache and data libraries. The physical material (tapes, disks or combinations) may be kept on shelves, off-site vaults or at remote disaster recovery sites. These various locations extend the structure of the archive beyond the local and traditional electronic media domain that we've been used to over the past couple of decades.
The archive manager is the traffic cop that continually tracks all assets as they move in and out of physical storage. The archive manager must be configured so that assets are accessible on demand for play-out or other purposes. This data movement process should be transparent, as close to automatic as possible, and tied closely to the facility's workflow procedures.
To support the management of these assets, a centralized archive database may be employed. Such a database is structured around established, well-known products such as SQL or Oracle, and must be future-proofed so it can be extensible to solutions the facility may have not yet identified.
INTERFACING
The archive manager's interfaces for both current and future subsystems will need to include broadcast automation, video servers, inexpensive disk storage, optical, tape and other high-capacity data libraries. Support for control of these subsystems must include industry standard control protocols, and allow for customized applications or middleware, which may be added or updated in the future.
To control the movement of content data between subsystems, the archive manager will employ a server that should be able to communicate with devices over industry standard protocols including: VDCP (Video Disk Control Protocol), VACP (Video Archive Control Protocol), and NDCP (Network Device Control Protocol). Depending on the vendor, these control protocols can be expected to be found in most media server architectures and associated peripheral transport systems. The archive server may actually communicate with datatape, disks, DVD or other optical media via other native protocols (e.g., SCSI or other like systems); but that interface should always be transparent.
Archive management systems should further have an open architecture application program interface that third-party developers can customize. The current trend uses XML, an established computer-centric language rapidly becoming the baseline communications language of choice, providing for extensibility as well as uniform system access to data structures and control schemes for various third-party middleware developers.
The centralized archive database should operate in real time, in turn giving an active picture of the location and status of all the assets it manages. Because movement of all media must be tracked--whether stored on video servers, intermediary cache, or data libraries--the archive database should include capabilities that allow active "looks" into all other primary and secondary databases for the various component of the system. These looks can provide secondary protection so inadvertent activities do not damage the integrity of the entire system.
Asset management systems now provide Web-accessible control, viewing, and manipulation of the material and associated metadata. The ideal archive manager should easily interface and extend directly into the asset manager systems. Because these systems integrate functions that supervise the ingest of material, the modification and tagging of related metadata, the development of low bit-rate proxies and in some instances, the digital rights management of that content through a single unified operator and system interface--harmony is extremely important.
Broadcasters transitioning to digital must further deal with issues associated with the migration to multiformat, multichannel broadcasting. Of course, this means that all new asset and archive management systems will require flexibility, as these material assets will be expected to include an entire gamut of video, audio, graphics and textual data. An archive systems' database must therefore be capable of identifying multiple formats of the same asset, such as an SD version with aspect ratios in 4:3 and 16:9; an HD version, classified by its appropriate scanning standard, and a proxy browse version with possible MPEG-2, MPEG-4 or other advanced coding structure.
Systems also will be expected to manage and track various conversion processes that will become more common as content repurposing increases. Low-res proxy and MPEG transcoding will extend beyond just localized browsing and searching. Looking at the advent of mobile handheld media and the ever increasing publication of content on the Web, expect to see yet another unique set of requirements that incorporate additional levels of transcoding as well--all of which must be tracked and managed online and offline.
Without question, the metadata associated with content becomes increasingly more dynamic as the multitude of formats increases. Portions of the metadata libraries will require continual adjustment based on how the metadata is associated with each asset. Asset management systems must be able to adjust to a hierarchy of data structures and convey those properly to the archive manager. The database must be capable of expansion at any point in time, with no negative impact on the end-to-end solution. Systems must also allow for facility processes and workflow functions to change, and for facility-specific syntax or terminology to be altered without constraints on how these changes occur.
Facilities routinely define their own metadata fields, so dynamic adjustments must be administered at one level and passed appropriately onto another. Even after a very large number of assets have been ingested and stored, adding new fields to the database must not be encumbered. When new fields are added, an update process should be capable of incremental and global updates to previous and new records throughout the entire database.
The archive management system becomes a tool set that helps maximize the amount of storage. By integrating high-capacity tape, spinning disks, and/or optical-data libraries, the asset and archive management system becomes an extensible and scalable solution for the growth expected in data storage and distribution. Thus, a properly selected, configured and administered asset and archive management solution can effectively extend the video server's storage capacity using recent advances in inexpensive disk storage.
Archive managers, while previously thought of as just the data movers in the overall digital media solution, are becoming increasingly important as more data is created, and storage management gets more complex. When looking at asset management systems, never sell short the archive manager component of the end to end solution.
Get the TV Tech Newsletter
The professional video industry's #1 source for news, trends and product and tech information. Sign up below.
Karl Paulsen recently retired as a CTO and has regularly contributed to TV Tech on topics related to media, networking, workflow, cloud and systemization for the media and entertainment industry. He is a SMPTE Fellow with more than 50 years of engineering and managerial experience in commercial TV and radio broadcasting. For over 25 years he has written on featured topics in TV Tech magazine—penning the magazine’s “Storage and Media Technologies” and “Cloudspotter’s Journal” columns.