Ten Tips for Choosing a Streaming Server

This article first appeared in February 2005 in the 2005 Streaming Media Sourcebook.The founders of the Academy of Motion Picture Arts and Sciences chose their name well. And, like the world of motion pictures, streaming media is both art and science. Choosing a great server involves weighing many sometimes contradictory performance and pricing options. Fortunately, with a few shrewd strategic moves, we can make it more science and less art.

Even if your organization doesn’t currently employ streaming media, administrators and end users need to know in advance that their infrastructure—networks, workstations, and servers—all are streaming media-ready. Unlike common office automation tasks, streaming media demands significantly better performance and capability from the infrastructure.

Fortunately, two pieces of the infrastructure puzzle—networks and workstations—have improved greatly over the last five to six years. A typical 100BaseT Ethernet network can support about 90Mbps of throughput or more than 300 typical streaming media sessions. (It could even handle up to nine 10Mbps MPEG-2 streams if you really wanted to push its limits.) If you are lucky, you may have Gigabit Ethernet installed at various workstations, which theoretically has ten times the capacity of 100BaseT and hence, support for ten times the number of streams.

For remote users, broadband connections represent more than half of the connections in the U.S. (It’s even higher in other countries.) So we can assume that a higher-quality, 500-700Mbps video stream would be the target on either system for our new media service.

We should say up front that we are discussing actual streaming content (on-demand or broadcast) and not a download or progressive download server scenario. The "download then play" approach more closely resembles traditional networking of data files, albeit rather large ones. The challenge of streaming content is latency—the need to keep the stream going so there is no interruption in the video or audio portion. In the download scenario, the file doesn’t play until it is all there, so there is no latency to worry about. Even if a large number of users requests content, each will eventually get that content, albeit very slowly.

Next, we are assuming that you are planning on streaming both audio and video content or just video—i.e., in one way or another, video is part of the mix. An audio-only system won’t be limited by contemporary servers, networks, or workstations. (OK, there’s always the potential for delays on the public Internet to cause audio reception to break off the stream, but that is far less common now than it was in the past.) For example, one test of audio streaming done a few years back showed that a dual Intel Pentium III Xeon 700MHz system with 256MB RAM on 100BaseT Ethernet could support more than 4,000 simultaneous stereo audio streams, with each stream averaging about 24Kbps.

Also, almost every contemporary workstation sold over the last five to six years will support streaming media. That is, pretty much anything that runs Windows 98SE up to Windows XP, Mac OS X, and Linux workstations will do fine.

So the discussion shifts to the server and how to make it ready for streaming. What follows are ten tips to help get you up and running.

Tip One
Here’s Tip One for choosing a server: Don’t.

What I mean is, if you don’t need to, don’t host the service yourself. Have a competent streaming hosting service do it for you. Let them properly configure a server to meet your external demand rather than trying to configure an in-house system yourself.

Naturally, the temptation is to take advantage of an existing, on-site, high-speed Internet connection to handle streaming in-house. While that may appear to be a cost-effective way to provide video services versus the $200-$300 a month fee that a service provider might charge, it too often isn’t.

Outsourcing provides a number of advantages. First, it avoids the need for designing, purchasing, and installing a new media server. Second, it eliminates problems with trying to adapt an existing system to include streaming. Trying to incorporate video streaming on existing servers could easily create bottlenecks and degrade current services. Remember, most enterprise or campus servers are geared towards small requests from many users, not large requests from many users. So caching and configuration parameters are often tightly focused on those needs rather than video content.)

Next, outsourcing eliminates a serious, often-overlooked single point of failure: staffing. In most enterprises, there’s just one person who is fully qualified to run the streaming media server. Should that person be "off-lined" (through accident, sickness, or just a well-deserved vacation), the company is left exposed to all manner of problems should the server go down. Having a good hosting service means there’s a qualified staff of engineers to run the streaming media server, not just an individual.

Equally critical, a hosting service will have several points of access to the Internet backbone. Should one link go down, the service is prepared to switch the streaming load over to the alternate(s). Compare this with most campus or business networks, where there is only a single telecom provider for Internet access.

A good hosting service will have a hot spare ready to provide failover service in case the primary media server dies. Whether you intend to charge people to view content or to pay people to view content in a corporate environment, the last thing you want is to cut those viewers off due to a hardware failure.

Finally, the hosting service also has far more bandwidth available to it than the average company or campus. So if there’s an unusual demand for content, the service can temporarily (or permanently) upgrade your connection to satisfy the demand. If demand soars at a company site, however, it might take weeks or months to upgrade the Internet connection and/or add more servers. This can be fatal if you need to support a for-profit on-demand streaming site.

One suggestion for choosing a potential host: see how quickly the company responds to your emailed request for information. If it takes more than 24 hours, you should consider another host. After all, if they are slow to respond to sales questions, imagine what might happen with support ones.