began as a simple concept: Use dedicated networks to send data more quickly
from a website to end users. Then about 17 years ago
came the first streaming video, which changed everything. The challenge for content delivery networks became greater and far more
Today, because of an avalanche of portable
Internet technology, we expect to be able to view all of our video at any time,
in any place and on any device. The breadth of platforms includes the home
television set, desktop and laptop computers, gaming systems, tablets and
smartphones. This trend of mobile communications has
spawned companies that specialize in providing all or a few of the estimated 30
discrete functions needed to make video programming instantly available on a
range of devices around the globe.
We haven’t achieved
this huge shift in mobile technology without a lot of significant change
occurring in a short period of time. It was at the NAB
Show in 1995 that Seattle-based Progressive Networks, led by Rob Glaser,
introduced RealAudio, the first technology to “stream” audio media over the
A little later that year, on Sept. 5, 1995,
Progressive made history when it broadcast a baseball game between the New York
Yankees and Seattle Mariners over the Internet using RealAudio. Within two years the company had changed its name to
RealNetworks and Glaser announced RealVideo, the first streaming video service.
The era of streaming media took off. By 2000, more than 85 percent of streaming
content on the Internet was in the Real format.
Glaser launched a media-specific network called RBN, for Real Broadcast
Network. It was the first content delivery network configured specifically for
streaming media. Despite RealNetworks’ early success,
the company could not hold onto its lead. The company’s primary business model
was based on the sale of its streaming media server software. In a competitive
end run, both Microsoft and Apple began giving away their own streaming media
technology. The free services dealt an economic blow to Real’s pioneering
The events that took place on Sept. 11, 2001,
affected the course of content delivery network development. The terrorist
attacks on New York City’s World Trade Center and other locations that day
overloaded the Internet as people tried to get news from a few primary sites.
The attack led to severe caching problems and revealed a flaw in the Internet’s
One of the victims of the
attack, Daniel Lewin, was a co-founder and chief technology officer of Akamai Technologies. He was
flying on company business in one of the jets targeted at the World Trade
Center. Coincidentally, Lewin happened to be an expert on the Internet overload
that occurred when he died.
At first, Akamai execs were
unsure whether the company could remain viable without Lewin. In an ironic
twist, however, it was the tragic loss of its leader that helped turn the
company around. After the attack, Web traffic for Akamai’s global network of
clients, especially major news media sites, surged by a factor of five. Lewin’s
technology had managed the spike handily, and his death had helped highlight
What Lewin and co-founder Tom
Leighton had invented with Akamai was a mathematical scheme called “consistent
hashing,” which distributed requests more efficiently among a changing
population of Web servers, resulting in greater speed. The system could also scale, meaning that it could expand as more people used it.
Lewin’s technology allowed millions of users to watch streaming video
simultaneously. It also ensured news web sites would stay online during global
crises that caused huge traffic spikes as people swarmed to sites for updates.
The September 11 attacks spurred greater investment in
expanding CDNs to provide greater Internet stability.
was with the rapid success of Apple’s iPhone in the summer of 2007 that the
idea of portable media consumption began to take hold. Apple followed up the
blockbuster iPhone launch with the unveiling of the iPad in the spring of 2010.
With these two devices, the concept of “media anywhere, anytime, on any device”
really took off.
In the past five years, as average
connection speeds to the Internet have increased, streaming media has evolved
into a genuine alternative distribution system for television and motion
picture programming. This evolution has driven the development of content
delivery networks even further.
A content delivery
network is essentially a string of web servers distributed across different
data centers in different geographical regions. Its goal is to serve content to
users with high availability and high performance, resulting in faster and more
CDNs are able to significantly boost
performance because of their large distributed server infrastructure, or
multiple points of presence. Servers store identical copies of content and apply
a mechanism that provides data to the origin servers. Today’s CDNs have many
data centers in different geographical regions. They deliver multimedia content
to end users from servers located closest to the user.
CDNs also incorporate cloud computing. A cloud infrastructure essentially
means that content providers no longer host their content on their own servers
at a fixed location, but instead give it to a provider, which places it on a
network of redundant servers located throughout the world. The cloud is
cheaper, works faster and eliminates a major operational and maintenance task
for content providers.
CDNs and their associated smaller
companies are growing. Cisco projected that its business grew between 40 and 45
percent last year and predicts the complete market will grow from $6 billion to
$12 billion by 2015.
Akamai is the leading CDN, based on
its global footprint (the company’s distributed cloud optimization platform
claims more than 147,000 servers in 92 countries within more than 1,200
networks), while Level 3 and Limelight follow. Verizon has acquired EdgeCast, a
leading CDN network, to enhance its portfolio of cloud and web services. The
telecom says EdgeCast will move into Verizon’s Digital Media Services unit when
the deal is completed this year.
content delivery expertise and a network of Internet content servers to Verizon
Digital Media, which is interested in improving and extending video delivery.
EdgeCast operates thousands of content servers in 30 Internet hubs around the
On a tier below the primary players that own and
operate their own networks is a larger group of niche companies that serve as
middlemen, providing specialist hardware and software services to clients such
as broadcasters and all types of video content providers. Virtually all connect
to one of the larger CDNs for distribution.
companies say they offer virtually every service to their clients, so figuring
out the strengths and weaknesses of each can be a significant challenge.
Edgardo Nazario, vice president of product management at
Limelight Networks, says his company offers every one of the functions needed
by content providers for distribution from any location to any device, at any
“You ask why there are so many players,” says
Nazario. “I would answer that there are a lot of wannabe players.”
Nazario, who began his career at Progressive Networks with Rob
Glaser, says Limelight’s clients want his company to manage their assets,
allowing them to focus on their core businesses. “That’s our value
proposition,” he says.
He says 50 to 60 versions of a
client’s content have to be created (transcoded) in order for that content to
be available to all the viewing devices throughout the world. Adaptive bit-rate
streaming allows video to be optimized for play on every device regardless of
the speed and condition of the network.
infrastructure of Level 3, another top-tier CDN, is called Vyvx. Vyvx is headed
by Derek Anderson, a senior director at Level 3. The company’s CDN began more
than 25 years ago, before streaming media, with the goal of helping move
traditional broadcast signals from satellites to fiber networks.
“We are unique because we deliver all types of content on an
end-to-end basis,” Anderson said. “We have connections to all the professional
sports stadiums in the States and can take terrestrial broadcast signals and
convert them simultaneously for delivery to Internet devices anywhere in the
One of the major trends identified by Level 3 is
the continual movement of television content from satellites to fiber networks.
One of the reasons is lower cost as the number of high-definition channels
continues to grow. Where bandwidth can be an issue on satellites, he said, his
networks can easily handle 4K resolution and above.
to compress a video signal more for use on a satellite does not compare well to
less or no compression on fiber,” Anderson said. “Better quality input equates
to better quality output and delivery.”
company targeting a variety of markets that want to distribute video, although
not a CDN itself, is Unified Video Technologies (UNIV), which has introduced a new
front-end interface for its white label uVOD video-on-demand service. The
technology enables subscribers to view real-time linear TV as well as on-demand
and VOD programming.
Edgar Moyano, business development
manager for Unified, says a broadcaster has to find a vendor for each of 30
pieces for any over-the-top solution. For each of those 30 pieces, he says
there are four to five options from other vendors.
company, he says, resells Akamai’s CDN, but supplies broadcasters with all the
pieces needed to transmit programming to the Internet. “We put their content on
our cloud, we define the workflows for the client, and they tell us the kind of
users they want,” he says. “We monetize the content and experience.”
He says his company acts like a systems integrator in creating
the service for the broadcaster and then nurtures the service in the future.
“We take the R&D risk,” he says. “We have the roadmap for the 30 pieces.”
He notes that his company’s close relationship with Akamai
benefits Unified’s customers. “We get new features Akamai is developing first
and can offer it to our customers,” says Mayano.
specialist company is Nevion of Norway, whose offering fills a niche not
covered by the major CDN players.
Janne T. Morstøl,
Nevion’s chief production and development officer, says her company specializes
in helping broadcasters get signals from sport arenas, events spaces and
government buildings. “We do the part that brings the content to the
broadcaster,” she says.
Nevion provides the hardware and
software required for media transport. It services both broadcasters and
service providers. She says Nevion’s competitors are Cisco, MediaLink and
“Our software is defined to make it
easy to manage both traditional and IP-based media networks. We make it easy
for broadcasters to set up a connection. Our clients don’t have to do a lot of
thinking. They can use non-trained people to set up the connections. They have
an overview of the system and are able to monitor the network. That’s what
makes us unique,” Morstøl says.
The demand for online
video content is increasing so quickly, it’s almost impossible to keep up with
it. Consumption of online video by consumers is exploding mainly due to the
increasing number of low-cost portable digital viewing devices and the
availability of higher bandwidth at lower cost. A maze
of functions that includes back office software, cloud storage, transcoding,
content delivery and customer monitoring opens the door to specialties from a
range of companies. Many are now staking out their niche in this rapidly