Please find below the submission of Marc Kaufman and Mark Simpson
representing Adobe Systems Inc.
        Steve Zilles, W3C Advisory Committee

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Adobe Systems is currently actively engaged in research and development of
real-time multimedia systems, and we are very interested in collaborating
with others as the work on web support for these technologies progresses
from
architecture to full deployment.

Adobe believes that it is important for a web multimedia system to include
the capability for description and rendering of geometric graphics and
typography, not just digital video and images.  The set of graphic elements
supported should be rich enough to encompass the capabilities of Java2D.
Issues such as rendering time prediction need to be addressed to enable
intelligent downgrading strategies.  Analogously, we believe that audio
capabilities must go beyond the ability to deliver and play sound samples.

The resources available during viewing will vary depending on static issues
such as installed devices and networks, and on dynamic properties such as
network and server load.  Screen resolutions will vary widely, as will
maximum available bandwidth.  Any web-based multimedia system must be
scalable across a wide range of quality levels and must allow for
intelligent downgrade in response to dynamic conditions. Adobe believes that
the ability to specify downgrade strategies in the authoring phase is
important.  An obvious example is choosing between delivering less
resolution or a lower frame rate in the face of bandwidth limitations.
Tradeoffs between audio and video are also possible.  It should be possible
for these choices to be made by the authors of content, not forced by the
system, and a rich environment for the specification of degradation
approaches is key.

Some of the features that Adobe imagines in a web-based multimedia system
would require substantial back channel control in the underlying real-time
protocols. For example, it should be possible to do panning in response to
user actions in a video game, and have the appropriate portions of
background video data retrieved.  As was the case in the development of the
byte serving protocol for web servers, we believe that Adobe can contribute
significantly to the discussion of requirements for the low-level protocols
underlying a real-time web-based multimedia system.

Adobe is highly interested in discussions of requirements and architecture
as a web multimedia system takes shapes.  Given our technical expertise and
current focus on related areas, we think that Adobe can bring a unique and
important perspective to these discussions.
*******************

Marc Kaufman
Adobe Systems
Mail W.15
345 Park Avenue
San Jose, CA 95110-2704
408-536-4777
marckauf@adobe.com

Mark Simpson
Adobe Systems
Mail M.7
411 First Avenue South
Seattle, WA  98104
206-470-7561
msimpson@adobe.com

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Stephen N. Zilles             |  e-mail: szilles@adobe.com   |
Adobe Systems Inc.            |                              |
P.O. Box 7900                 |  tel: (work)  (415) 962-4766 |
1545 Charleston Road          |       (Admin) (415) 962-4751 |
Mountain View, CA 94039-7900  |  fax:         (415) 962-6063 |
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