Television Broadcast - June 1999
NAB 99 - The Year of the
By Sheldon Liebman
Walking around this year's NAB, it seemed that every booth was offering products that were called servers. There were video servers, video file servers, streaming media servers, broadcast servers, and more. In some cases, different types of servers offered similar features. In others, different features were available from products that were referred to as the same "type" of server.
We've been covering servers for a number of years, but there still isn't a single accepted definition of the term. This month, we'll try to sort out the issues involved in defining servers, although we really can't offer the final and correct meaning of the term. That's a decision that only you can make, based on the exact needs of your facility.
Sorting Through the Possibilities
Back when computers and video spoke completely different languages, video servers were basically library systems that used control software to access videotapes and play their content through one or more inputs to a routing system. If the router was part of a television station, the output went on the air. In a production facility, it might go to the edit room. In a corporation, it could be piped to a closed circuit network.
Today, there are many different pieces in the video server puzzle. Instead of videotapes, most servers are using disk-based storage to provide digital information. In some cases, all of the server storage is disk-based and available on-line. In other cases, on-line storage is linked to a videotape-based library system and material is constantly shifted between on-line and archive storage. It probably doesn't matter which method is being used, as long as the system can be considered scaleable. This requirement comes from a simple truth - no matter how much storage you have available today, you need more tomorrow. Any product that wants to be called a server must have a way to expand in the future.
Redundancy is an issue that usually goes along with scalability. As a system grows over time, it's important that your information is protected. Many companies have learned the hard way about the problems of old videotape, but digital storage is not immune to problems. Some servers are designed for short-term storage and may not include any type of extra data protection. Others incorporate RAID (redundant array of independent disks) technology in one form or another to rebuild data that may become corrupted. How important this is for your facility depends on what kind of information you are serving and whether there is any type of independent backup system in place.
Another issue is the format of the stored material. In the previous paragraphs, it's easy to assume that the server creates a video signal. But what type of video signal does it create? Is it analog NTSC or PAL, CCIR601 or one of the new DTV formats? Is only one type of video signal enough, or does a "real" server need to support multiple formats (either one at a time or simultaneously)? What about compression? Which form(s) of MPEG can be used or do we want to require our servers to store and playback uncompressed video streams. The issues of resolution and compression alone can fill an entire article.
Some products called servers don't even get into these issues. Instead, they provide information as data files, creating a whole new set of problems. As early adopters of video compression systems learned, all data files are not created equal. If System A is used to create and store a file, System B might not be able to play it back. Universal translation may be a reality in the world of "Star Trek," but 20th century Earth needs a little more help.
Although "full resolution" video is typically what we try to achieve, multimedia formats as small as 160x120 pixels can be "served" as well. This has become more important with the growth of the Internet and corporate intranets. Do we need or want video at all?
In my office, for example, I have a number of computers that are connected through a Fast Ethernet (100 Megabits per second) network. If one of these machines contains low resolution, Apple QuickTime movies and the other machines play these movies at various times of the day, it can be argued that the source computer is acting as a video server.
If the files are on a disk array attached to that computer instead of on the machine itself, is the array the server or is it still the machine? Does the fact that these are low resolution files affect whether we call this a video server? Shouldn't we call it a MultiMedia Server or maybe just a file server?
Finally, in this example we aren't actually turning the movies into a traditional video signal. Does this mean we aren't serving video or is it enough to know that the original material was created in a video format? What if the material is 3D animation that was rendered directly to the QuickTime format and has never been recorded onto videotape? Does this affect whether we have a video server?
Fast disks, fast computers and fast networks can be used to "serve" video across Local Area Networks (LANs) and even across Wide Area Networks (WANs) without having a single traditional video connection. The source is a file and the destination is a computer screen.
Things get a little more confusing if you actually create a video signal as part of this loop. For example, if one of the computers viewing the movie is equipped with a video-compatible display card, the display adapter itself can turn the movie into a composite or component video signal. If it wasn't a video server system before, does this turn it into one? Now, we can make the movie available as an input to a router and send it over a traditional video network. What if we use a scan converter instead of a video-compatible display adapter? Does this affect how we refer to the system?
Next we can look at the area of how the equipment is being controlled. In the examples above, the system looks and acts like a computer network. If we call something a video server, are we implying that it should be controlled by video equipment? Does it need to interface to a station automation system or look like a traditional VTR to other video equipment?
Digital Disk Recorder technology has grown by leaps and bounds over the past few years and devices that used to store seconds or minutes of material are now capable of storing many hours of information. In a really large configuration, a DDR system can even replace a traditional library system. Does this turn a DDR into a video server?
Once we move into equipment that can be controlled by video equipment, do we need to require that it support recording as well as playback functionality? With computer-based systems, we can obtain video data from a number of sources. One of these is through video capture, but this is not the only one. Do we need to capture video directly onto a system in order to call it a video server?
A Little of This, A Little of That
Now that we've looked at the areas that can be used to define the term video server, we can look at some of the companies that create products addressing these issues. Depending on where your personal definition fits, the list of suppliers could include virtually every computer and storage manufacturer on the planet. Since we don't have enough space to list them all, here is a small sample of the companies and products that were shown at NAB.
Ciprico offers a number of UltraSCSI and Fibre Channel disk arrays that support compressed and uncompressed video playback with bandwidth up to hundreds of MegaBytes per second (MBps). Ciprico disk arrays can be configured from a few GigaBytes (GB) up to over a TeraByte (TB) of storage and can be combined for larger storage and/or higher bandwidth requirements.
Eurologic is a company with an OEM focus on the film and video markets. Recently, they introduced their own brand, the Voyager series of storage solutions. Voyager solutions are based on high-speed disk arrays with performance of up to 200 MegaBytes per second (MBps) and are compatible with Mac, Windows and SGI environments. Storage capacity ranges from 18 GigaBytes (GB) to multiple TeraBytes (TB).
HP's MediaStream family of products includes the MediaStream Broadcast Server, MediaStream Disk Recorder and MediaStream Connect software. Using these products, broadcasters can create disk-based solutions for spot insertion, multi-channel broadcasting, network delay, program playback and archiving and Near-Video-On-Demand (NVOD). MediaStream products utilize MPEG-2 compression and Fibre Channel connectivity and are compatible with automation software from a wide variety of companies. A single MediaStream server can have over 100 hours of on-line storage and networked solutions can support over 1000 hours of on-line storage.
At NAB 99, Leitch introduced the VR400 MPEG-2 server, a high-end product featuring Fibre Channel storage, software RAID technology and multi-format codec technology. The product is expected to ship beginning next month and existing ASC VR300 systems can be upgraded to this new technology. The VR400 provides bi-directional video channels for recording and playback, eliminating the need to configure dedicated encoders and decoders. It also supports simultaneous recording, storage and playback of MPEG-2 4:2:2 and MPEG-2 4:2:0 formats. Leitch announced at NAB that the product will support DVCPRO25 and DVCPRO50 in the future.
Omneon Video Networks
Exhibiting at NAB for the first time, Omneon Video Networks is a new company that has developed an open, scalable system they call the Video Area Network. It enables customers to route, store and share digital audio, video and data and the company provides the switches, network interfaces, storage systems and software that are used to create the network. A wide variety of formats are supported as part of the Video Area Network structure, including uncompressed component digital video, DV, MPEG, compressed HD and even Internet Protocol (IP) data. The Omneon concept encompasses LANs, WANs and SANs as part of the Video Area Network structure.
If you want to serve up DVCPRO video, Panasonic offers two products that might fit the bill. The AJ-DR7000 is based on the Windows NT platform and offers four physical I/O ports and an internal bandwidth equal to seven DVCPRO streams. It can also record at 4X normal speed when connected to the Panasonic AJ-D780 VTR. With optional interface cards, the AJ-DR7000 also supports SDTI, SDI and analog video formats. Panasonic's other new offering, the AV-SS500 Video Production Server, is an eight-channel DVCPRO server that can record and/or play up to eight video streams simultaneously and offers up to 20 hours of internal storage.
Pinnacle has entered the video server market with their new Thunder and iThunder products. Thunder features four video (4:2:2:4) and audio channels with support for MPEG-2 and DV storage formats. It also includes an asset management system and a downstream keyer on each channel for live compositing. The system looks like a BVW-75 VTR to most video products to allow seamless integration into facilities and broadcast stations. iThunder is a companion product that allows viewers to access and see video proxies via standard streaming technologies on the Internet.
Pluto currently offers two product lines in the Digital Disk Recorder category and also has a Video Server product. Their VideoSPACE Digital Video Recorder offer 8- or 10-bit uncompressed video recording and playback. The newer HyperSPACE and HyperSPACE HDCAM Digital Video Recorders provides either 3 hours of HDTV capability or 4 hours of SDTV. The company also offers the AirSPACE and AirSPACE HD Multi-Channel Broadcast Servers, which can provide any combination of 10 Serial Digital or Fibre Channel networked streams and supports DV compression at either 25 Megabits per second (Mbps) or 50 Mbps. Last October, Pluto announced a deal with Sony Electronics in which Sony will integrate the HyperSPACE HDCAM into high definition applications and systems.
NAB 99 marked the U.S. debut for Quantel's new Inspiration integrated news and sports production system. Inspiration handles everything from editing through playout of finished video. The company also markets the Clipbox video server, featuring up to 160 hours of online storage and the ability to edit material within the server with no copying, transfers or bottlenecks. Quantel's Cachebox offers a new eight port configuration, 100 hours of DVCPRO storage and the ability to upgrade to HD at a later date.
SeaChange offers the Broadcast MediaCluster product line in two configurations, the 1200 Series and the 800 Series. The main difference between the two is that the 1200 Series includes 12 disk drives per node and the 800 series features 8 drives per node for reduced cost. According to SeaChange, the Broadcast MediaCluster product line offers full fault resiliency without mirroring the entire system. This is accomplished by striping across multiple nodes of disks, a technique they call RAID SQUARED. The result is that a SeaChange system can tolerate up to three points of failure without losing information, compared with other systems that can tolerate only a single point of failure.
Sierra Design Labs
Sierra Design offers a number of products that provide uncompressed video storage and playback in a standalone or networked environment. QuickFrame offers up to 120 minutes of 4:2:2:8 or 10-bit video. DiskCovery is smaller and lighter than QuickFrame, but offers similar features. SCSIFramer is a department-level video server that uses 2 or 4 buffered UltraSCSI ports to concurrently serve multiple workstations with high-performance video.
SGI's Origin servers combine industry-standard digital video interfaces with high-speed networking, guaranteed-rate I/O and media management software from SGI and third party providers. These combinations can be used to create systems that support multi-format, multi-channel playout as well as video-on-demand and news applications.
Sony offers a wide variety of configurations for video storage and multi-channel output. Newsroom servers and On-Air playout systems can be custom designed to meet the needs of small, medium and large facilities. As mentioned above, Sony is partnering with Pluto Technologies to incorporate Pluto's products into Sony's server systems.
The Profile family of products now includes over 13,000 server channels around the world and over 50 application developer partners. The newest product, the PDR400, supports the DVCPRO format and joins the PDR300 MPEG Video Server and PDR200 JPEG Video Server products.
As part of their digital news systems, Vibrint offers the Vibrint VideoServer, a computer-based video server and VCR replacement designed for capturing, sorting and playing out video. The product acts as a bridge technology between legacy broadcast infrastructures and computer-based networks. For compatibility with a variety of environments, the VideoServer supports industry standard protocols including Sony BVW-75, Odetics and Louth VDCP.
Are We Being Served?
As mentioned above, the number of products that can be classified as video servers depends heavily on the definition you choose to accept for this term. This year's NAB helped us to see the range of possibilities, but didn't move us toward a single definition of this term. So, if you're looking for a video server and a company claims they have one, be sure to ask a lot of questions.
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