Commentary: Mamas, Don't Let Your OVPs Grow Up to be CDNs
"Mamas, don't let your babies grow up to be cowboys," lamented Willie Nelson (and a variety of other cover artists). "Let them be doctors and lawyers and such."
Along with Flash, HTML5, and HTTP streaming—all very popular topics on StreamingMedia.com—one other topic continues to receive significant buzz: online video platforms (OVPs).
With great interest often comes great confusion, however, so I'm going to use this brief article to highlight the primary differences I see between OVPs and their content delivery network (CDN) siblings.
The reason I lump both OVPs and CDNs into the same family is fairly simple: Depending on your perspective, an OVP is either just a grown-up CDN or a CDN-wannabe that hasn't reached full potential.
OVPs: CDN Wannabes?
The "OVP as CDN aspirant" view essentially sees the OVP as a poor-man's CDN aspiring to leverage its video service into that of a large-scale CDN. After all, the argument goes, CDNs can do such more, as they are based around the idea of delivering large files.
Many CDNs deliver software updates and a variety of other large, non-video files, so CDN proponents view delivery of on-demand, progressive-download videos as just another type of large-file delivery.
Since CDNs deliver large files over via generic HTTP servers, it's not surprising that CDNs would look to leverage that infrastructure to meet the rising demand for HTTP streaming. While it is certainly true that the majority of on-demand "streamed" files are actually delivered as progressive-download videos, it is equally true that HTTP streaming allows for lower delivery costs and easier maintenance-failover-fallback than it does from specialized streaming servers.
True on-demand streaming video, whether via a specialized streaming server or generic HTTP server, is an infrastructure that a CDN can build out alongside its core large-file delivery. A fair number of CDNs also do true live streaming in which a video is delayed slightly—typically 6-8 seconds—distributed on an as-needed basis in a highly time-sensitive manner, consumed on the viewer's computer or playback device and then abandoned directly after viewing.
Given the number of HTTP servers that a CDN has on hand, it's also likely that CDNs will continue push their core file-delivery expertise into generic HTTP video delivery. HTTP not only delays delivery slightly but also simultaneously fragments files into 2-10 second chunks in a variety of bitrates and resolutions. This means that on-demand and live streaming solutions from Apple and Microsoft leverage the native server operating system's inclusion of Apache and IIS HTTP servers, respectively, to create a one-stop compress, chunk, and stream solution.
Based on all of this, the common wisdom goes, it's an easy stretch for a CDN to play in the OVP space, but much harder for an OVP to reach the level of a CDN.
Except that most OVPs aren't looking to become CDNs. After all, surrounded by 800-pound gorilla infrastructures from key CDNs, why would OVPs even want to compete with CDNs from a significant size disadvantage?
Interestingly, most OVPs don't view themselves as competing against CDNs. Rather, they leverage nimbleness and technology alongside focused specialization on video delivery to differentiate video delivery from any other type of file delivery.
Even more interestingly, this singular focus is becoming attractive to CDNs that might want to quickly and cost-effectively diversify into the OVP space.
So what are the basic elements of an OVP? In a nutshell, there are four basic elements.
Most OVPs are housed in data centers, often with redundancy across multiple data centers, just like a CDN. High availability is key to delivery robustness, as are fairly wide pipes: Most upper-end CDNs and OVPs have 10GigE (Gigabit Ethernet) connections at their data center, complete with peering arrangements with multiple data transport companies, resulting in limited "hops" from the data center to the end user.
Often the OVP will have a self-provisioning feature, allowing a customer to set up an account and post content online in less than 30 minutes time. Older CDNs, or larger ones, often require a significantly lengthy sign-up process and credit check, where OVPs and smaller CDNs offer instant sign-up via a credit card. Another key element of this is the commitment length: Some require a year or longer commitment while others offer a month-to-month service.
While the ability to keep the data center delivery up and running is a given, what we mean here by 2/47 availability is the ability to do round-the-clock streaming of a live feed. This is important for customers who might have particular events that last over the course of several days or weeks. When looking for an OVP that offers 24/7 streaming availability, be sure to check for those who not only know how to set up a 24/7 video stream but also those who are adept at maintaining the stream for days or weeks on end.
Customized video players
While most CDNs will offer a single Flash or Silverlight player, a few will require the CDN subscriber to roll their own player and serve it up separately from the file delivery that the CDN excels in. An OVP, by contrast, often provides customizable players that can be skinned (or overlaid with various custom graphics) and controlled via on-screen, pop-up, or hidden controls.
A few extra features, added on for good measure, include automated playlist creation, which allow the content creator—or even a more traditional television programmer—to build up a TV channel of sorts that plays content back-to-back. Some OVPs allow these playlist channels to be played back in a 24/7 setup that plays regardless of the number of viewers, while other OVPs even allow the playlists to cut between live and on-demand content, in much the same way that a television news show has live and pre-recorded elements.
A final feature that some OVPs offer is a pre-built advertising server to monetize ad-driven content.
From CDN to OVP?
So what about the view of an OVP as the natural maturation of a CDN?
I personally think this is the more accurate view, as OVPs tend to offer the same features as a CDN plus some additional key features.
Not only do OVPs offer on-demand, progressive download and live streaming, they often offer automated encoding and transcoding (to allow the live or on-demand files to be viewed on desktops, laptops, mobile phones, and TV set-top boxes).
The one thing that sets mature CDNs apart from newer OVPs is their ability to handle high-profile streaming experiences. But the growth of OVPs, which focus exclusively on video delivery and customized playback, means that OVPs are increasingly adding high-profile event video delivery to their repertoire.
Of course, in the end, we may find that CDNs move more toward video delivery, becoming OVPs of sorts, which is beginning to happen with some of the more nimble CDNs. This course of action is much more likely than OVPs wanting to become CDNs—or even cowboys—when they grow up.