Computer: Video Streams into the MainstreamDocument Transcript
for creating CD-based video applications.
Video Streams It is still widely used for this purpose.
However, QuickTime did not initially
support streaming. Users had to down-
load entire files before viewing them,
into the thereby restricting online video to die-
hard hobbyists with either fast Internet
connections or a lot of free time.
Several years later, companies began
Mainstream releasing commercial streaming-video
technologies. Some of the early vendors
included VDOnet (which stopped selling
its software earlier this year), VxTreme
George Lawton (since acquired by Microsoft), and
Progressive Networks (which changed its
name to RealNetworks).
The most important technological
he widespread adoption of advance that enabled streaming video
streaming video on the Internet was the development of technology for
appears ready to become the buffering and managing the ﬂow of data
next major frontier for online as it arrives on the client. Now, the client
multimedia. sets up a TCP or UDP connection with
Graphics, animation, and audio tech- the server and requests that content be
nologies have already proliferated on the streamed into the client’s buffer. The con-
Internet. However, streaming video—in tent is then managed by the player and
which viewers can begin watching con- streamed from the buffer.
tent almost as soon as it starts down- This permits streaming-video servers to
loading—is only now developing as a send compressed ﬁles in a continuous
mainstream technology. stream over the Internet, an intranet, or
“In the past 18 months,” said Alex an extranet. The user views content in a
Benik, an analyst with the Yankee Group, with [asymmetric digital subscriber lines player, which decompresses streaming ﬁles
a market research ﬁrm, “streaming video (ADSL) service] and cable modems.” and sends video data to the visual display
has evolved from being a toy to some- People are also using broadband ﬁxed- and audio data to the speakers. There are
thing that service providers of all kinds wireless and satellite technologies for stand-alone players and those that users
can hope to generate revenue from.” Internet access. can integrate into a browser as a plug-in.
The Gartner Group, a market research In addition to spurring consumer appli- QuickTime, RealPlayer, and Windows
firm, estimates that the portion of US cations, streaming video also promises to Media can work both ways.
companies using streaming media has fuel corporate applications over intranets Servers can distribute streaming video
almost doubled, from 9 to 17 percent, and extranets to support distance learn- on demand from prerecorded ﬁles or as
since last year. ing and training, corporate communica- a live broadcast feed. With live video,
Benik said two of the key factors dri- tions, marketing, and advertising. servers must be multicast-enabled so that
ving this trend are the increasing adop- In fact, said analyst Cushing Anderson they can efﬁciently send content to mul-
tion of broadband services that speed of IDC, a market research ﬁrm, stream- tiple viewers at the same time. Figure 1
Internet access for users and the devel- ing video will help drive sales of distance- shows how this works.
opment of backbone networks that speed learning applications from $1.1 billion A typical 56-Kbps modem connection
the delivery of content by providers. in 1999 to $7.1 billion in 2002. can provide only the traditional small
In the past, video has been too data A number of companies provide video window because it doesn’t have
intensive for most users. However, the streaming-video technologies, but the enough bandwidth to support the amount
growing use of broadband technologies major players are Apple’s QuickTime, of data necessary to ﬁll a larger screen.
has spurred the rapid growth of stream- Microsoft’s Windows Media, and Real- However, broadband Internet-access
ing media, according to Martin French, Networks’ RealVideo. products and better compression/decom-
vice president at MeTV.com, a streaming- pression (codec) technologies will let users
video content provider. “A year ago,” he VIDEO-OVER-IP BASICS take advantage of the newer streaming-
said, “the only people with fast Internet Apple pioneered digital video technol- video approaches that deliver full-screen
access were with companies with T1 lines. ogy in 1991 with the development of video at 500 Kbps and even higher qual-
Now we are seeing an awful lot of people QuickTime, which was originally designed ity video at 1 Mbps.
By and large, only users with T1 or
fiber connections can currently take Sender’s
advantage of these technologies. local
Theoretically, cable modems offer a
maximum transmission speed of 10 Server
Mbps, while DSL modems offer up to 1.5
Mbps. But in practice, consumers typi- Internet
cally receive only 200 to 300 Kbps of sus-
tained throughput, so they generally can’t
make full use of the new streaming-video
technologies, according to Ben Rotholtz, Network
RealNetworks’ general manager of prod-
ucts and systems. However, he said, cable
and DSL carriers are expected to deliver Network Network
600 to 900 Kbps as they upgrade their router router
Subscriber’s Subscriber’s Subscriber’s Subscriber’s
KEY PRODUCTS local local local local
The three most popular streaming-video router router router router
products are Apple’s QuickTime 4 (which
has been integrated into the MacOS but
which can also be downloaded separately),
Microsoft’s Windows Media 7 (which has
been integrated into Windows but which PC Laptop Television PC
can also be downloaded separately), and
RealNetworks’ RealVideo 8 (which runs Figure 1. A live streaming-video feed uses multicasting to send ﬁles to multiple viewers at the
on the company’s RealPlayer). same time. The camera shooting the live scene sends its video and audio feeds to a server,
The basic clients are free, although which then distributes the data as a single stream into the Internet. With multicasting, the data
Apple and RealNetworks also sell en- is maintained as a single stream until it gets close to the recipients, at which point it is copied
hanced clients. and redistributed. This avoids the bandwidth consumption that would occur if a different data
Microsoft also sells NetShow Theater stream had to be sent from the server to each recipient. Multicasting also helps with scaling.
Server, a high-end product that delivers
full-screen, broadcast-quality video over
high-bandwidth networks. NetShow is Both technologies’ clients support all Windows Media also includes digital-
primarily designed for use over high- major platforms. rights management technology, which
speed LANs and intranets, and its con- The Windows Media server runs only protects content providers’ intellectual
tent can be run on a standard Windows on Windows, while the client supports property. The technology lets content
Media player. only the Macintosh and Windows plat- owners prevent recipients from distrib-
Users can access small-screen, lower forms. uting material without the author’s per-
quality video from all three streaming- mission.
video products with 56-Kbps and even Advantage to QuickTime Content producers are concerned
slower modems. However, users who QuickTime is the oldest of the online about unauthorized distribution of their
want high-quality video must be able to video technologies. According to Frank material. Therefore, streaming-media
access the Internet at 500 Kbps for Casanova, Apple’s director of QuickTime companies want to convince producers
RealVideo 8, 700 Kbps for QuickTime, product marketing, the product is sup- that it’s safe to provide quality content
720 Kbps for Windows Media 7, and up ported by more applications, including for Windows Media.
to 8 Mbps for NetShow. The difference even Microsoft Word and Excel, than
in access requirements is based on the competing technologies. Advantage to RealVideo
products’ different codec algorithms. An advantage of RealVideo is that con-
Advantage to Windows Media tent providers can encode ﬁles so that
Platform support One advantage of Windows Media is clients can access them at different speeds.
The QuickTime streaming server sup- that it is integrated with other Windows- The client can then select the best access
ports the FreeBSD, Linux, MacOS, Solar- based technologies. This makes it sim- rate based on the available bandwidth.
is, and Windows operating systems. The pler to implement and utilize for some
RealVideo server supports the Linux, Windows users, especially those without BATTLE IN THE MARKETPLACE
Solaris, and Windows operating systems. signiﬁcant technical experience. The streaming-video market pits Real-
July 2000 13
I n d u s t r y Tr e n d s
Media Broadband Jumpstart coalition to ment at the Internet’s edge. The servers
encourage increased adoption and im- accept a video stream from a content
provement of video and audio over high- provider’s master server and duplicate it
speed connections via Windows Media. for recipients closer to the source.
Percent of US Internet users
About 100 streaming-media-related com- In addition, telecommunications com-
Unique users (millions)
panies have joined the coalition. panies such as AT&T, GTE, and Sprint
15 Meanwhile, Apple and Microsoft have Communications have let RealNetworks
recently licensed QuickTime and Win- deploy its own edge servers throughout
dows Media for free to RealNetworks. If their networks. Apple has launched a
RealNetworks supports the technologies, similar infrastructure for QuickTime on
this could encourage content providers to top of Akamai Technologies’ large con-
5 develop more material for QuickTime tent-distribution network.
and Windows Media because the content Meanwhile, some content providers
could then also be shown on RealPlayer. distribute their material via multicasting,
0 The Yankee Group’s Benik said that which transmits one stream of data that
RealPlayer Windows QuickTime
although RealNetworks is the market is copied and redistributed close to the
leader, the company is at a crossroads multiple recipients. This avoids some of
and must decide if it wants to be a tech- the problems caused by the increased
nology innovator, a multiservice Web bandwidth consumption that accompa-
Figure 2. Of the major commercial streaming- portal designed to attract visitors and nies growing streaming-video usage.
media technologies, RealNetworks’ Real- advertising, or a broadcast services Sometimes, providers can’t avoid con-
Player has the biggest US market share by far, provider. He said, “I don’t think they will gestion. Burst.com has an application
followed by Microsoft’s Windows Media and be successful going in all three direc- called Burstware that sends video data
Apple’s QuickTime. tions.” across the backbone in quick, large
bursts for storage in a cache, which then
Networks, a company whose only busi- STREAMING INTO THE FUTURE buffers the material. If a data transmis-
ness is media, against Apple and Micro- Streaming video faces several key tech- sion is delayed over the network, the user
soft, which have other business interests. nical and business challenges. can play content from the cache.
As shown in Figure 2, RealPlayer has Interoperability. Streaming-video tech-
23.5 million unique users, representing Technical issues nology will need more standardization
29.41 percent of the 80 million US The key technical issues facing stream- to become truly widespread. Currently,
Internet users; Windows Media Player ing video include Internet congestion, all the major streaming-video players
has 9.4 million users, representing 11.75 interoperability, and compression. support QuickTime.
percent of users; and QuickTime has 7.2 Internet congestion. Currently, online Microsoft’s Active Streaming Format
million users, representing 8.98 percent video is subject to transmission inter- (ASF) is a low-overhead, open ﬁle format
of users, according to a survey conducted ruptions because of Internet congestion, for storing streaming-multimedia con-
this year by Nielsen//NetRatings, a com- particularly for users with lower band- tent. The company designed ASF to opti-
pany whose activities include the mea- width connections. mize content delivery and to integrate
surement of Internet-related audiences. Several network service providers— and synchronize different media types.
To advance their positions, Microsoft such as AboveNet Communications, For example, ASF enables the synchro-
and RealNetworks have purchased and Digital Island, and Exodus Communi- nization of images with an audio track.
invested in other streaming-video com- cations—are selling access to their high- RealNetworks supports ASF. However,
panies. And both companies, as well as bandwith networks to streaming-media Microsoft does not support RealVideo.
Apple, are working with providers to content distributors. This lets distribu- These types of practices force some devel-
develop compelling content for their tors bypass most Net congestion. In addi- opers to either design content in one for-
technologies. tion, some service providers, such as mat, thereby losing audiences that use
Microsoft is concentrating on devel- iBeam Broadcasting, have developed other formats, or spend additional time
oping Windows Media technology and satellite distribution networks, which and money to develop, store, and serve
integrating it into Windows. Apple and broadcast streaming-video signals to the content in multiple formats.
RealNetworks, on the other hand, are edges of the Internet, again avoiding Compression. Data-compression algo-
trying to increase marketplace support most Net congestion. rithms are critical to providing quality
for their products with a multipronged Some providers avoid congestion by video at lower transmission speeds, so
approach that includes media-publishing using other schemes to send transmissions work is continuing on better codec tech-
and consulting services. from the Internet’s edge to recipients. For nologies.
Last September, Microsoft promoted its example, vendors such as GMV Network Currently, Microsoft uses a slight vari-
technology by forming the Windows have developed proxy servers for deploy- ant of the MPEG-4 codec algorithm. In
fact, Windows Media is the only stream- ﬁrst quarter of this year. The company as brief news clips and short ﬁlms. Most
ing-video player that uses the MPEG-4 also reported profits for the last two providers give away their content, leav-
standard, said Leonardo Chiariglione, quarters of 1999. ing them with only such revenue sources
convener of the Moving Picture Experts Apple spokesperson Vanessa Rios as advertising.
Group, a standards organization for would not provide figures but did say A few providers, however, such as
digital-media codec technology. that the company is making money from Kanakaris Communications (http://www.
Nielsen//NetRatings analyst Jarvis its QuickTime technology. kkrs.net) and MeTV.com are developing
Mak said RealNetworks’ two-pass en- Microsoft did not return calls for libraries of pay-per-view content. In fact,
coding is currently the best compression information about whether its stream- MeTV.com has developed a converter
technology. According to Mak, this tech- ing-media operations are proﬁtable. box that lets a computer wirelessly send
nology analyzes an entire video before Technology vendors. One way that audio and video to a television. MeTV.
encoding it to determine how best to Apple and RealNetworks hope to make com’s French said, “Streaming video will
compress the video on the second pass. money is by selling servers and services. not take the place of TV, but companies
This reduces the final video file size, Microsoft, on the other hand, would like like ours need to pump [content] to the
RealNetworks’ Rotholtz said, but the to sell more of the NT servers required to TV to get people to watch it.”
two passes require 15 to 20 percent more stream Windows Media content. In However, streaming-video content
time to carry out than a single pass. addition, increased use of Windows itself will have to be compelling for user
Media could contribute to the increased interest in the technology to grow. “In
Business issues use of the Windows OS, Microsoft’s core the last six months, there has been a huge
As is the case with many technologies, product. proliferation in the number of sites with
vendors are trying to ﬁgure out how to Content providers. Content providers video. The problem has been that no one
make money from streaming video. also must determine how to make has offered the kind of content that con-
Earlier this year, RealNetworks an- money with streaming media. Most sumers want,” said Gartner Group ana-
nounced proﬁts of $8.75 million for the streaming video consists of content such lyst Sujata Ramnarayan.
July 2000 15
I n d u s t r y Tr e n d s
According to French, companies will
have to alleviate content providers’ fears Streaming Video with Java This approach has several advan-
about piracy and distribution control tages, according to John Graham,
In most streaming-video technolo-
before they make more popular content founder of Graham Technology Solu-
gies, users have to download plug-in
available. tions (http://www.graham.com), which
or stand-alone clients that play con-
tent that must be compatible with the makes a Java applet and server used
LOOKING AHEAD client platform. However, a number of for streaming content from such
Industry observers question whether sources as live events, scientiﬁc instru-
companies, such as the Geo Interac-
Microsoft will overtake RealNetworks. ments, and satellites. For example, he
tive Media Group (www.emblaze.
They wonder whether the situation will said, there is no plug-in to install or
com), are taking a different approach
turn out like the browser market, in which update.
by developing Java applets for stream-
Microsoft’s Internet Explorer caught and In addition, because the applets use
passed longtime leader Netscape Navi- Java, they can work with content
When downloading content that
gator, or like the Internet service provider developed on almost any platform,
works via a Java applet, a user with a
market, in which Microsoft’s MSN said Jarvis Mak, an analyst with
Java-enabled browser also downloads
hasn’t come close to catching the front- Nielsen//NetRatings, a company that
the applet. The content is then streamed
runner, America Online. measures Internet-related audiences
through and viewed on the applet, which
MeTV.com’s French said the stream- and activities.
is then cached on the user’s machine.
ing-media marketplace battle will take
place primarily between Microsoft,
which wants a role in the media-inten-
sive Internet world of the future, and be as important a player and will appeal Other vendors have tried to play an
RealNetworks, whose sole business is primarily to Macintosh users and graph- important role in the streaming-video bat-
multimedia. He said QuickTime will not ics designers. tle but have failed because the three major
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players have not left room for another
leading competitor in the market.
The Gartner Group’s Ramnarayan
said RealNetworks is the market leader
in part because it has developed a kind
of ecosystem for its technology. It has a
large consumer base for its players, a
large content base, and a large set of
tools, with each element feeding the oth-
ers, she explained.
However, said Rob Enderle, a vice
president and research leader with the
Giga Information Group, a market
research ﬁrm, Windows Media is catch-
ing up with RealNetworks’ technology.
Moreover, he said, Windows Media is
part of the integrated Windows platform,
which means it is less complex and thus
more attractive to users.
As for the technology itself, MPEG’s
Chiariglione said he expects it to remain
largely the same in the near future, except
perhaps for widespread adoption of dig-
French predicted that researchers will
develop better compression encoding
technologies during the next two or three
years, which will improve video quality. Complete the online application
A growing trend is the use of Java applets
for streaming media. (See the sidebar and
“Streaming Video with Java.”)
Eventually, Enderle said, a range of
machines, including Walkman-like de- • Get immediate online access
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French said, “Streaming media is the
future and is coming fast. We saw music • Sign up for a FREE e-mail alias
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July 2000 17