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Vidyo, Inc 2006 - Confidential

A Ready Market - 8

increased bandwidth needs associated with high definition further stress the requirements for

network resiliency and efficient multipoint processing.

Image Format

Pixel Resolution

Megapixels per Image

SQCIF

128 x 96

0.012

QCIF

176 x 144

0.025

SIF

352 x 240 (NTSC)

0.084

CIF

352 x 288

0.101

4CIF

704 x 576

0.406

4SIF

704 x 480 (NTSC)

0.338

D1

720 x 480 (NTSC)

0.346

D1

720 x 576 (PAL)

0.415

HDTV

1280 x 720

0.922

VGA

640 x 480

0.307

XGA

1024 x 768

0.786

Figure 1 Pixel resolution for different image standards

Scalability

When enterprise managers talk about scalability of videoconferencing, they are referring to

the need to support large numbers of information worker desktops with a wide range of CPU

and memory resources connected over IP networks with varying network loads. The

heterogeneous nature of receivers makes it difficult to deliver a single video stream to all

with acceptable quality. The concerns are even more poignant on the part of service

providers attempting to support hundreds of thousands or even millions of consumers using

broadband connections to the home.

Scalability also involves support for multipoint conferences ? conferences involving more

than two endpoints. Multipoint chat sessions have introduced many consumers to the value

of such calls, and videoconferencing users have long demanded such capabilities in their

systems. Multipoint requirements however significantly raise the challenges for call

reliability and fault tolerance because multipoint calls often connect endpoints with very

different capabilities on networks with different performance levels into a single conference.

Ease of Use

Enterprise workers have long been disappointed with the ease of use of desktop

videoconferencing. Products have not been able to support ad-hoc calling or multipoint

conferences, and desktop solutions for video have not generally been able to support the call

answering, call forwarding, hold and transfer, and voice mail functionality that most

information workers expect. The result has been lack of acceptance and a stagnant market.

This is all in the process of changing however, as major enterprise vendors like Avaya, IBM,