# Designing a Collaborative Virtual Conference Application: Challenges, Requirements and Guidelines
## 2 Related Works
### HCI and Collaboration  
Human-Computer Interaction (HCI) research has focused on computer systems that have a group impact, mainly on Computer-Supported Cooperative Work (CSCW). CSCW is based on how groups work together and how technology affects group behavior [8]. A groupware is a set of software tools that support a group of people working together. Different theories have been created to combine the cooperative work of people through hardware, software, and networking. One of the theories that have been created is the CSCW matrix theory. The time space matrix is used in CSCW matrix theory to categorize groupware [9]. The first dimension is concerned with whether the interaction can be performed at the same time (synchronous) or at different times (asynchronous). The second dimension is considered when the individuals are located at the same location (collocated) or at different locations (remote). Combining these two-dimensions has resulted in four categories of groupware for CSCW: co-located and synchronous, remote and synchronous, collocated and asynchronous, and finally remote and asynchronous. Figure 1 shows the different example applications being categorized in the time space matrix.  
Figure 1: The time space matrix for CSCW: (**a**) The interface of Video Conferences for different location same time Tabletop System matrix [10]; (**b**) Example of different location and time using email application [11]. (**c**) Tabletop System for same location and time matrix [12]; (**d**) Kiosk System for same location different time matrix [13].  
Referring to Figure 1, each of the quadrants has its own set of advantages and disadvantages. For example, quadrant 1 is doing collaborative tasks at the same time and same location. This benefits tasks that are performed directly face-to-face. There is no input and output delay between users, as they can collaborate quickly without the use of the internet. However, performing collaborative work at the same place and time requires a larger space for users to move around and a bigger system for it to collaborate effectively. Collaborative Multi-Mobile System (CMMS) is an example of CSCW with the same time and location, where users can place multiple mobile devices on the table in a collocated manner to create a large surface for collaborative activity [14; 15]. Quadrant 2 is carrying out the tasks at different times but at the same location, such as the kiosk. The benefit is that information can be shared at any time without the need for the parties to meet. However, users must return to the same place to retrieve the information required. Quadrant 3 has the advantage of performing collaboration at different locations at the same time without meeting face-to-face. However, the downside is that it requires a higher bandwidth to stream videos over the distance. Depending on the internet quality, the streaming can sometimes be delayed by a few seconds. In collaborative works, users want to make quick changes but the delay in real time application can cause frustrations. Finally, quadrant 4 collaborates at different locations and times. Although there are no delays with this method, users are rarely able to perform any real time-based activities for quick actions and changes.  
This paper focuses on synchronous collaborative interaction groupware in quadrant 3 of the time space matrix. Examples of groupware that support synchronous collaborative interaction groupware are virtual conference applications, remote desktop applications, instance messaging, and multiuser text editing [16]. The research has mainly focused on the current video conference or telecommunication used by current users to communicate at a distance and at the same time using text, audio, and video.