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Limelight Networks takes on the Olympics

The Olympics often serve as a forum to announce the arrival of a nation onto the world stage. This summer, the games also will herald the arrival of Internet television as an important video distribution medium worldwide.

The on MSN Web site is providing 2200 hours of live and 3000 hours of on-demand video content of the games to Web viewers in the United States. Delivering that content to Web viewers at home and at work is Limelight Networks in Tempe, AZ.

Relying on its own fiber-optic network, petabytes of computer storage and delivery centers sitting on the edge of nearly 900 last-mile networks, Limelight Networks is anticipating the 2008 Beijing Olympics will herald the mainstreaming of Internet-delivered video.

This week, IPTV Update speaks with Limelight Networks spokesman Paul Alfieri about the massive project.

IPTV Update: Limelight Networks is the primary CDN for all video content for the “ on MSN” Web site. Can you give me the lay of the land in terms of the traffic you are expecting, the bit rates being offered?

Paul Alfieri: We’re not directly giving traffic or bit-rate projections, but there are a lot of details I can talk about. First, Limelight Networks has been involved with some of the largest Internet broadcast events. Just within the last six months, there was the Oprah Winfrey Book Club, which had more than 525,000 online viewers. There was Disney’s debut online with the movie “Camp Rock,” with more than 860,000 plays in a 24-hour period in June.

We believe the Olympics have the potential to break all of those records, and we’ve been preparing with that in mind.

IPTV Update: How are the delivery centers being provisioned?

Paul Alfieri: The unique thing about Limelight Networks is that we operate a second-generation content delivery network architecture.

The first-generation CDNs were born around 10 years ago, when the Internet was full of static objects like graphics or HTML pages. What those CDNs did was build out an architecture that could efficiently deliver a static Web page into the last mile.

When we were founded seven years ago, we recognized the Web was becoming a rich media, entertainment platform. So we took a radically different approach to building a CDN, which is what enables us to handle an event like the Olympics.

We start off with Petabytes of storage. When I say Petabytes, we’re approaching 5PB in our network, so Petabytes of storage that are directly positioned to deliver content right into last-mile networks. We have direct connections from these servers to almost 900 last-mile broadband networks around the world.

What that means is we can serve content from anywhere using these servers, and we’ve got the capacity to store and serve entire libraries of content directly into the last mile without the content having to traverse the public Internet.

IPTV Update: How does the content get to the server? What if a piece of content that a viewer on a given last-mile network wants to see isn’t on that network?

Paul Alfieri: This is one of our unique differentiators. We interconnect all of those servers with our own media-grade optical network. So, rather than having to move content through the Internet to position it at the edge for the last mile, we can move it at the speed of light to anywhere in the world across our own private network.

What that means is a few things. As we move that content, it is not subjected to the congestion on the public Internet, so there is a lot more certainty for us as we deliver the content because we know that as the first bit is delivered, the second bit is going to be right behind it. That enables us to offer a high degree of efficiency in delivering content, whether it is live or on-demand, that we can turn around and deliver into the last mile.

Specific for the Olympics, will be making 3600 hours of total content available. What our network enables us to do is to deliver those bits of live or on-demand programming directly into the last mile, essentially bypassing much, if not all, of the public Internet congestion that might be occurring in the U.S. at the time. Additionally, for the on-demand events, we can have the files stored and positioned in our servers right at the edge of the last-mile broadband networks. This means the viewer is only one or maybe two router hops away from the content that they want to see. That enables a great user experience because the video won’t buffer, it won’t stutter, there won’t be a “waiting room,” and it will play in its highest fidelity as soon as the user clicks to watch it.

IPTV Update: Obviously, a major thrust of NBC’s presentation of the Olympics on television is high definition. There are some strictly defined characteristics of high definition for playback on television. Will Limelight be presenting a high-def Internet presentation of the Olympics, and what exactly does HD mean when it comes to the Internet?

Paul Alfieri: We at Limelight Networks believe that “high definition” is a statement of resolution. If you look at the formats, you have 720p and 1080i or p. That’s what we fundamentally believe is the definition of high definition. In the Internet realm, you will hear a lot of people define a high-definition file using a file size or a maximum bit rate. We believe those are secondary factors to the primary definition of high definition, which goes back to the resolution of the image.

Delivering a high-resolution file requires a certain amount of bandwidth versus delivering a standard-definition file. In cases such as the Olympics, we work with our customers to dedicate a certain amount of our egress capacity on our network specifically to ensure we can delivery the content to all users in the quality the publisher wants, based on their projected audience size. We’ll look at our model to be sure we have enough reserve bandwidth to preserve that high-fidelity stream that is going to the end user.

The other piece for the Olympics is that NBC is delivering using Microsoft Silverlight 2.0 technology, which offers an adaptive bit-rate codec that can help maintain a great-looking picture by dynamically adjusting the stream to the variations that occur in the last-mile network or the home network.

IPTV Update: What unique requirements do live streaming of an event and on-demand replays pose?

Paul Alfieri: There are two challenges when delivering any type of content over the Internet. The first is delivering one piece of content to a million people. We believe that while that is a very difficult problem, a larger challenge is delivering to a million audiences of one.

On the Internet, you have live and on-demand streams, and every single user is able to access any particular piece of long-tail content that is available. Now, each one is a valuable eyeball that the content publisher wants to monetize. In order for the publisher to monetize that, the experience has to be just right.

If the video stutters, if it doesn’t play right, if it doesn’t look right on the screen, if the user gets stuck in a “waiting room,” all of those things could impede the viewer from continuing to watch, and therefore the publisher won’t generate revenue on that viewer.

So, when it comes to something like the Olympics, the challenge of delivering live streams is making sure the content is always available and the experience is always great, regardless of where or when the viewer wants to watch. We have seven years of experience in doing this. Now, Limelight can’t see inside the last 10ft network, whether it’s a home network or an office network, and sometimes if the configuration is not right, or a home router isn’t set up right, that could impede viewing a bit.

What we try to do with our approach is eliminate as many of the quality barriers that happen in the public Internet. So, as I said before, eliminating the router hops, making sure we have enough storage to position the entire library of Internet content at the last mile so that it’s right there and ready to stream.

Those are the challenges, and whether it’s live or on-demand, they are the same. In fact, in the case of the Olympics, while we are streaming live down to the end user, we are also capturing and making available immediately on demand so you will be able to rewind something almost instantly if you liked it, essentially going from live mode to on-demand mode instantly. From our perspective, the challenges are the same, and when it comes to the Olympics, we have to account for both at the same time.

IPTV Update: I was wondering if you were familiar with the FCC’s decision to slap Comcast’s wrist when it came to network management measures it had taken to impede the use of certain applications, namely BitTorrent, that could compete with Comcast VOD offerings. As a content delivery network, do you run into other last-mile providers who use means like deep packet identification to discriminate in terms of the support offered?

Paul Alfieri: I’m only familiar with the case from what I’ve read in the news. I’m not really in a position to comment on the specifics.

IPTV Update: Is there anything else you’d like to add about the Olympics endeavor?

Paul Alfieri: The one thing I would add is that in addition to working with Microsoft and NBC on the Olympics, we do work with all the large content publishers on a variety of different projects. Our work with these large-scale customers has to continue even while a large-scale event like the Olympics is going on. That’s a technical challenge that goes above and beyond the feat of getting the Olympics delivered, and it’s something that I’d say if you are an engineer, it’s something you would appreciate and also understand. It’s not just about the single big event; it’s about maintaining the scale of the business.

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