Pattern-Based Tool Design for Shared Knowledge Construction - Collaborative Technologies and Applications for Interactive Information Design - page 27

Figure 2. CURE abstractions

shows the abstractions that are offered by CURE .
Users enter the cooperative working/learning en-
vironment via an entry room that is called Hall .
Rooms can contain pages, communication chan-
nels, e.g. chat, threaded mail, and users. Users,
who are in the same room at the same time, can
communicate by means of a synchronous com-
munication channel, i.e. by using the chat that
is automatically established between all users in
the R o o m . They can also access all pages that are
contained in the R o o m . Changes of these pages
are visible to all members in the R o o m .

The concept of a virtual key is used to express
access permissions of the key holder on R o o m s .
Each key distinguishes three different classes of
rights (J. M. Haake, Haake, Schümmer, Bourimi,
& Landgraf, 2004): key-rights defining what the
user can do with the key, room-rights defining
whether or not a user can enter a R o o m or change
the R o o m structure, and interaction-rights speci-
fying what the user can do in the R o o m . R o o m s
with public keys are accessible by all registered
users of the system.
Users can enter a R o o m to access the com-
munication channels of the room and participate
in collaborative activities. Users can also create
and edit pages in the R o o m . Pages may either be
directly edited using a simple wiki-like syntax
(Leuf & Cunningham, 2001), or they may contain
binary documents or artifacts, e.g. JPEG images,
Microsoft Word documents etc. In particular, the
syntax supports links to other pages, other R o o m s ,
external URLs or mail addresses. The server stores
all artifacts to support collaborative access. When
users leave the R o o m , the content stays there to
allow users to come back later and continue their
work on the R o o m ' s pages.
Figure 3 shows a typical R o o m in CURE . The
numbers in the figure refer to details explained
in the following paragraphs. A R o o m (1) contains
documents (cf. C e n t R a l i z e d o b j e C t s ) that can be
edited by those users, who have sufficient edit

R o o m

Problem : Users use different tools for commu-
nication, file transfer, application sharing,
and other tasks that are needed in group
interaction. In most cases, these tools are
used together. However, setting up the
tools is difficult and time-consuming.
Solution : Model a virtual place for collaboration
as a room that can hold documents and par-
ticipants. Ensure that users who are in the
same room can communicate by means of
a communication channel that is automati-
cally established between all the users in
the room. Make sure that all users can ac-
cess all documents that are in the room and
make these documents persistent. Changes
to the documents should be visible to ev-
eryone in the room.