Content
Delivery Networks: A New Opportunity
By Jim Ray*
INTRODUCTION:
While some “dot coms” are falling by the wayside
due to anemic revenue and funding, most infrastructure companies are
enjoying strong revenue growth and a healthy bank account. The reason? Without optimal
infrastructure, B2B and B2C applications will not work. Physical evidence
of the infrastructure build-out is everywhere, from crews laying fiber
along major highways to telco and cable trucks locally upgrading central
office and head-end equipment.
What is less obvious, but sure to be equally compelling, is the
activity of satellite service providers expanding and re-purposing their
traditional broadcast capacity to cash in on the Internet content
distribution and delivery (CDD) opportunity.
The Internet is essentially a federation of
decentralized networks making a best effort at delivering content. While
networking technology is improving at a rapid rate, the average request
for a Web page still traverses about 17 terrestrial network exchange
points, each of which has a propensity for delaying transmission or losing
packets during transmission.
Using satellite rather than terrestrial transmission reduces the
number of exchange points and improves network reliability and
performance. Recognizing
this, satellite service providers and operators plan on winning big in
what Jupiter Communications predicts will soon be a $6 billion Content
Delivery Network (CDN) market.
SATELLITE
SERVICE PROVIDERS – Distributing and Delivering Content to Multiple
Locations
Satellite technology is an ideal match for the CDN
market. CDNs replicate and distribute Web content to multiple facilities
in dispersed locations. When
that content is requested by users, it is served locally, rather than from
an origin server which may be a great distance away. Because satellite networks
are inherently multicast enabled, they achieve significant economies of
scale when distributing content to multiple locations simultaneously. Multicasting, however, is not an
inherent capability of the terrestrial Internet, which puts terrestrial
CDNs at a cost disadvantage in distributing content to thousands of
locations .
Early adopters in the satellite CDN market are
aligning with content distribution and delivery (CDD) infrastructure solution
partners and rapidly deploying equipment in large quantities. The best CDD
infrastructure solutions include:
Popularity based caching –
Caching appliances increase network performance and reliability and
conserve upstream bandwidth.
Every downlink facility or point of presence (PoP) will be equipped
with network caches that locally store popular Web objects as they are
requested by end users. There are many caching vendors on the market, but
most lack necessary multicasting capabilities. Multicast-enabled caches
are essential for satellite networks to complete the multicast “push” of
content. Look for caches that can operate via one-way IP over satellite
with an asymmetrical terrestrial return link, and via two-way IP over VSAT
for the most flexibility. When employing two-way connectivity, look for
cache providers that provide HTTP acceleration techniques to mitigate the
impact of satellite round trip latency on the TCP protocol.
Scalable and reliable
streaming media delivery - Today’s streaming solutions
are being sized to distribute up to 100,000 simultaneous broadband streams
from the downlink facility or other downstream node to end users. For
maximum flexibility today, CDNs should support all major formats including
Windows Media, Real G2, QuickTime, MP-3, MPEG-1. While on-demand streaming is
forecasted to comprise the lion’s share of the streaming market going
forward, live streaming is crucial to particular applications like
real-time sporting events, live corporate addresses and others. Also, live streaming is a core
competency of satellite service providers; content must be sourced from
its origin, yet satellite networks avoid the majority of bottlenecks in
terrestrial networks. The ability to translate live multicast streams to
unicast in real-time is an essential feature for satellite CDNs. Today, some streaming
infrastructure vendors offer full streaming server functionality at the
edge while others limit their offerings to a subset of these
capabilities. Analysts
believe next-generation applications will require complete server
functionality at the edge.
Traffic
management – Directing both global and
local traffic to optimal nodes is essential for a satellite service
provider focused on quality. Locally, switches and load balancers use a
variety of techniques to spread the workload evenly among available
servers or to direct particular traffic types (HTTP, active server pages,
transactions) to the appropriate device for optimal handling. Optimal load
balancing for streaming media applications is a more complicated algorithm
and is being addressed by a handful of vendors. Without this feature,
streaming infrastructure will not generate its highest capacity. Globally,
end users requesting content are directed to the node in the service
provider’s network that can best serve the request quickly and
reliably. While this can be
highly dependent on geographic location, other deciding factors include
the current workload on each node, and the traffic congestion between each
node and the end user.
Intelligent content
distribution and management – This component orchestrates
the centralized distribution of content to remote nodes and is essential
to the satellite service provider’s value proposition: the efficient
distribution of content to many locations. The ability to logically group
specific nodes is essential for customized content distribution. Advanced offerings also
incorporate reliable multicast techniques and forward error correction to
guarantee the quality of distributed content. Combining this intelligent
multicast content “push” with the unicast content “pull” derived from end
user requests provides the opportunity to create tiered services through
local content hosting and insures high quality of service and
differentiation in the marketplace.
Content-oriented features -
These capabilities, like
user authentication, targeted advertisement insertion, real-time hit
forwarding and billing integration, are essential for all service
providers looking to monetize their access customers’ eyeballs. Complete solutions that offer all
of these functions generally consist of a number of technology partners
working together with network infrastructure providers.
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CONCLUSION
The best solutions are modular and allow the
service provider to upgrade gradually as the business expands. Starting
with full-function caching and using the cache as the foundation for the
entire solution will allow for a more manageable deployment.
While today’s Internet is primarily a terrestrial
network, many satellite service providers and operators appreciate they
have a distinct advantage over current terrestrial
networks. They are moving quickly to capitalize on this opportunity. When deploying CDD infrastructure
solutions choose your partner / vendor wisely. When possible, it is faster
to work with a vendor that supplies a broad product portfolio of
field-tested CDD components as opposed to identifying unique vendors for
each component.
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*Jim Ray is a product marketing manager at InfoLibria, where he is responsible for industry analysis, product positioning, and solutions marketing. He can be reached at jray@infolibria.com.
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