Chapter 26 -- How Intranet Whiteboard Applications Work





Chapter 26
How Intranet Whiteboard Applications
Work


CONTENTS


How Intranet Whiteboard Applications Work




Increasingly, people's work is done not with pen and paper-it's
done with computers. That means that one traditional way that
people collaborate-by sitting down with pen and pencil and marking
up each other's work-is no longer possible.

Online mark-up started with word processing programs offering
simple "strikeout" and "redline" styles. Changes,
however, were done sequentially, one person at a time. This often
caused great delays in document production. It was also difficult
to make annotations in documents, although "comment"
styles were possible. Another difficulty was keeping track of
who made which changes or remarks. This was improved upon by the
introduction of color coding revisions by authors. Despite these
advances, it was still cumbersome and time consuming for a group
to work online on documents. Furthermore, while these features
rapidly become common in word processing, other applications like
spreadsheets didn't offer similar controls. One other problem
was that all the people working on the document usually needed
to have the same version of the software to work collaboratively
at all.

True document collaborative possibilities emerged when someone
recognized that whiteboards-a board on which special markers are
used that can easily be wiped off-provided the concept that could
help move online mark-up into the realm of the actually useful.
These whiteboards are not physical objects set up in rooms. Instead,
the whiteboard software resides on the client's desktop. Every
computer screen has the ability to become a whiteboard. In addition
to writing on a blank whiteboard, people can "write"
directly to the documents by writing on their computer screens.

What they write is immediately visible to the other people viewing
the document on their screens. People can mark up the budget by
circling or otherwise marking items, each using a different color
to help identify the author. Different programs also provide a
variety of tools, such as erasers and spray cans. Participants
can also discuss the comments as they make them.

The next generation of whiteboard applications will allow participants
not only to mark up what is on each other's screens, but also
to actually change the data as well. Presently, only the originator
of the document conference can physically change the data. In
the future, however, no doubt there will be controls that allow
or restrict the changes that people participating in a whiteboard
session can make. Participants will be able to talk about a budget,
change the figures on the spot, and perform a "what-if"
analysis. Moreover, participants will be able to do this even
if they do not have the software for the file on the whiteboard.
For example, if they were working on an Excel spreadsheet, they
would not have to have Excel on their own computer.

How Intranet Whiteboard Applications Work

A whiteboard application refers to software which
allows people to simultaneously view and annotate a document on
their computer screens. Each participant would have a different
color assigned so that the authorship of changes is easily visible.
The participants in a whiteboard conference can also talk to each
other while they are circling or otherwise pointing to the section
of the document they reference in the discussion. Document conferencing
by whiteboard applications allows for truly collaborative working.
There are a number of companies developing this type of software.
This illustration is based on how the CU-See-Me whiteboard works.

The CU-See-Me whiteboard works in concert with its videoconferencing
software. (See Chapter 25 for more information about how videoconferencing
works.) The software works on a client/server model. People run
the CU-See-Me client on their computer and they log into a special
server called a reflector. When you log into a reflector,
you can join any whiteboard conference found there. When someone
is logged into a reflector, a signal goes out regularly from the
person's computer to the reflector, telling everyone connected
to the reflector that the person is logged in and available for
a conference.
In a whiteboard conference, you can see what is on other people's
computer screens, and they can see what is on your screen. You
can also mark up what is on your screen or their screens by using
your mouse or stylus as a drawing tool. In the same way, they
can mark up what is on your screen. People participating
in a whiteboard conference can see multiple screens on their computer
at once-so that they can be participating in marking up several
screens at the same time. People can decide to only view the markings
of certain people in a whiteboard session-they can "turn
off" the markings of some people.
When you participate in a whiteboard conference, a special
protocol is used for sending data packets. The protocol allows
data to be sent to many people at once, instead of having to specify
sending it to an individual-that is, to multicast. The
packet is sent to the reflector, which multicasts it. However,
the protocol also works similarly to TCP: It checks to see whether
every packet in the data has been sent. If every packet hasn't
been sent, the protocol re-sends the packet until every packet
is received.
The protocol has been designed so that it can keep resending
data to those people who haven't received all the packets, but
not resend to those who have received the packets. For example,
if four people are participating in a whiteboard conference, and
only one person hasn't received all the packets, the reflector
will re-send the packets only to the individual who hasn't received
all the packets.
The multicast protocol used by CU-See-Me allows for the whiteboard
session to be broadcast to a large number of people simultaneously,
and any one of those people can choose to participate in the whiteboard
conference. It is also possible to participate in whiteboard sessions
without having to go through a reflector. However, when reflectors
aren't used, intranet administrators are not allowed to do things
such as control the bandwidth used for whiteboard sessions. See
Chapter 25 on videoconferencing for information about how intranet
administrators can use reflectors to regulate sessions.
In the future, whiteboard applications will allow people not
merely to mark up documents, but to work together on the document,
even if they don't have the application that created it on their
own computer. People would be able to put in new figures in a
spreadsheet, for example, and engage in group "what-if"
scenarios, without everyone having to have the application that
created the data on their own computers.