Streaming audio and video initially emerged as a consumer medium used
for entertainment purposes such as music, news, sports, and movie
trailers. Now it is becoming a delivery platform for businesses,
universities, and government agencies, leveraging on-demand streaming for
global access to training and general enterprise communications.
One hot application for corporate streaming is e-learning, projected by
Gartner Group to become a $34 billion market in 2005, up from $2.1 billion
in 2001. Video streaming is an important component of e-learning since
people show greater attention and retention through visual experiences.
Supporting this premise, UCLA professor Albert Mehrabian has authored
several books that recognize body language as the most effective tool that
generates knowledge retention, followed by voice tone and word choice.
Perhaps this is why high-quality, video-based e-learning is superior to
static initiatives which often fail to have a significant and lasting
impact on students.
Combined with the Internet, video-based e-learning can leverage the
familiar user interface of a Web browser and the ubiquitous access of the
Internet, making training available virtually everywhere, at anytime. This
allows organizations to reach every target student and offers an
effective, self-paced learning mechanism -- providing consistency in
course content and the ability to measure completion rates and retention.
Success Depends On Two Factors
The success of a video-based e-learning solution depends on two primarily
factors: compelling, effective content and the ability for the user to
access content efficiently with consistently high-quality service. The
overall solution must also scale to meet anticipated enrollment and usage
patterns. Important questions to ask before determining the best streaming
solution needed: Will tens, hundreds, or thousands of students access the
system during peak usage periods? Are these users geographically dispersed
in a home-type environment, or are they clustered in groups such as branch
campuses or remote offices? Do users have LAN access, broadband access, or
dial-up access to the learning management system (LMS)?
Compelling Content
State-of-the-art production tools and high-performance PCs allow for
quick in-house production of high-quality video content. Depending upon
the size of the organization and training purpose, this can be as simple
as capturing a classroom lecture with an accompanying slide presentation,
or it can be a studio-quality production with role playing created by
professional actors and courseware designers. Training material that is
company specific -- such as new product launches -- will require custom
courseware development, whereas "soft skills" training -- like
sales skills and customer support -- may be purchased from experts in the
field and then augmented with company-specific content.
Whichever creation path is chosen, material that is too general or
dated will have limited long-term value. Course material that is specific
and concise keeps audience attention and leads to higher course completion
rates and knowledge retention -- 30 minute topics are much more effective
than 3 hour lectures. Also, by providing the user access to on-demand
features such as rewind, pause, and jump, the user can control his
experience and learning pace.
User Access
If there are concerns about video e-learning, the biggest comes from the
IT department required to support high-volume streaming within the current
infrastructure. While most text, Web pages, and pictures can be downloaded
fairly efficiently, video streaming requires that a constant bandwidth
connection be maintained between the client and the server during the
entire streaming experience. This concern in understandable, considering
that five concurrent users pulling 300 Kbps streams fully consume a single
T1 line.
There is no disputing that the combination of compelling content, high
course completion rates, and broad organizational acceptance of video e-learning
will result in higher utilization of the IT infrastructure, but remember,
this is an indicator of a successful training initiative. The increased
load is manageable. Decisions regarding how the increased load is handled
should be based on the ROI expected from the training initiative while
taking into consideration the concerns of the IT department -- not the
other way around.
Delivery options associated with e-learning content are detailed in the
chart below. The chart shows the recurring monthly WAN charges that are
required to support streaming clients in WAN and LAN environments.
| |
T1
WAN |
T3
WAN |
100
Mbps LAN |
Gigabit
LAN |
| Concurrent
Users |
5 |
150 |
> 300 |
> 600 |
| Monthly
WAN Cost |
$1,000 (estimate) |
$10,000 (estimate) |
N/A |
N/A |
| Monthly
WAN Cost Per User |
$200.00 |
$67.00 |
$0.00 |
$0.00 |
It is important to notice that once the content is on the LAN, hundreds
of concurrent users can be supported locally without further impacting WAN
bandwidth. Through the use of hierarchical network design and LAN
switching technologies, even larger numbers of clients can be supported
locally without impacting other LAN-based applications.
Building A Streaming Delivery Network
There are several methods for delivering training content to a broader
audience; the proper one for a given deployment requires a balance between
cost, ROI, and utilization. The fundamental choice is between expanding
the centralized streaming capacity or migrating to a distributed,
edge-streaming environment. Other alternatives include an outsourced or
hosted model, or a hybrid approach combining elements of centralized and
distributed environments.
When opting to increase capacity in a centralized model, the T1
interface can be upgraded to a T3 connection. With this approach, the
number of concurrent users jumps by a factor of 30 times the original user
count, with the monthly WAN cost per user decreasing by 65 percent. While
the monthly WAN expense increased from $1,000 to $10,000, this may be the
preferred and most economical approach when many remote locations with few
users must be supported. Other services are available between T1 and T3
rates which may better balance bandwidth and expenses.
Another option is to maintain the current WAN infrastructure and deploy
edge-streaming devices at branch campuses and remote locations. The remote
locations will then be able to support hundreds of users locally while
sharing the same T1 interface. Streaming content is pulled over the WAN
only once, and is then delivered as needed to the local users. With
capital costs for the devices less than $20,000 and monthly savings of
$9,000 versus upgrading to a T3, payback is achieved in about two months.
This approach is ideal for locations that require concurrent training
access to 10 or more students.
Whichever method is used, other factors need to be considered when
building a streaming delivery network, such as server protocol support and
full interoperability with other server and client software. This is
generally assured through vendor certification processes. The server
product must be fully interoperable with the target content format,
whether it is Microsoft Windows Media, RealMedia, QuickTime or MPEG.
The server must also be able to scale to support the anticipated
workload. Factors to consider include on-demand performance needs, storage
requirements, and the ability to deliver the highest levels of quality of
service.
Conclusion
Streaming has clearly moved beyond the phase of consumer novelty.
Organizations such as Samsung Electronics, M.I.T., and the U.S. General
Services Administration have all embraced streaming to support core
operations in commercial, educational, and government sectors.
These enterprises use streaming because the benefits are clear:
Streaming provides much greater speed and agility when compared to
obsolete training methods like CD-ROM distribution. Streaming also
provides broad access to distributed users and allows the training
experience to be controlled based on a user's schedule and learning pace.
Most importantly, streaming provides for efficient communications that
assure organizational alignment and training effectiveness.
Eric Kraieski is vice president of marketing for Vividon.
Vividon builds streaming appliances that radically improve the economics
of delivering audio and video over networks. The Vividon SDA device is
suitable for centralized and distributed streaming applications in
enterprise, edge and service provider environments. Supporting a wide
range of applications including broadcast audio, large file downloads and
full video-on-demand, the SDA appliance has been independently tested for
interoperability by Microsoft and RealNetworks.
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