# Survey on Quality of Experience Evaluation for Cloud-Based Interactive Applications
## 3 Categories of CIAs
### Remote Desktops  
A remote desktop is a CIA that allows users to connect from a local computer to a remote one as if they were sitting in front of the remote computer. The local computer may have low computing resources, and it is called a thin client. The remote computer is usually a virtual machine running on a shared server, although it can also be a dedicated computer. In this CIA, the thin client captures the mouse movements, clicks, and keystrokes to be sent to the remote computer where the application is running. These interactions can prompt screen updates that are then sent back from the remote computer to the thin client. The thin client is only a kind of forwarder of user actions. Remote desktops allow mobility for users (the remote computer can be accessed from any device and at any place) and reduce management and maintenance costs. Some remote desktop applications specialise in performing remote assistance functions, such as TeamViewer [59] and Google Remote Desktop [60]. Other solutions are designed for continuous use, such as Windows Remote Desktop [61], VMware View [62], and Citrix [63]. Remote desktop solutions based on the deployment of remote computers on virtual machines are referred to as virtual desktop infrastructure (VDI) solutions. Amazon Inc. provides this type of infrastructure through a public cloud with the Amazon Workspaces service [64]. The use of remote desktops increased drastically due to the pandemic situation in 2020-2021. For example, in the information technology sector, the increase in remote desktop deployments was 258% in 2022, with more than three-quarters of employees using remote desktops [65; 66]. The percentage of companies offering remote work, and therefore, remote desktop solutions, increased from 51% at the start of 2023 to 62% in 2024 [67; 68]. In this type of CIA, the user wants to control a remote computer as if it were a local computer, without any noticeable delay or loss in image quality. For example, by clicking to close a window, the user expects the window to close immediately. Two main human perceptions can influence the final QoE. The first is interactivity or responsiveness. The lag between user interactions (keyboard or mouse) and the screen updating as a result of these interactions can affect user experience. For example, clicking a window and moving it around the desktop. The user is accustomed to a local environment. The shared virtualisation server and access network in remote desktops can increase the response time to user actions, with a serious impact on QoE. In most remote desktop services, the server sends the screen updates as it generates them. For example, Sun Ray [69] and Lap Link [70] prepare and send screen updates using this method. In other cases, such as Citrix or Windows Remote Desktop, the server bundles multiple intermediate screen updates to send only a single relevant screen. The client may also send a display update request to the server instead of waiting for a triggered update. The VNC protocol [71] specifies that the \begin{table}
\begin{tabular}{c c c} \hline \hline
**Remote Desktops** & \
\begin{tabular}{c} **Cloud Gaming** \\ **Services** \\ \end{tabular} &
\begin{tabular}{c} **Interactive Web** \\ **Applications** \\ \end{tabular} \\ \hline [PERSON] et al. [33], [PERSON] et al. [34], [PERSON] et al. in [37], [PERSON] et al. [38], [PERSON] et al. [41], [PERSON] et al. [42], & [PERSON] et al. [35], [PERSON] et al. [39], & [PERSON] et al. [36], [PERSON] et al. [40], \\ [PERSON] et al. [41], [PERSON] et al. [42], & [PERSON] [43], & [PERSON] et al. [44], \\ [PERSON] [45], & [PERSON] et al. [46], & [PERSON] et al. [47], \\ [PERSON] et al [31], & [PERSON] et al. [48] & [PERSON] et al. [31] \\ [PERSON] et al. [49] & [PERSON] et al. [50] & \\ \hline [PERSON] et al. [51] & \\ \[PERSON] et al. [52], & \\ [PERSON] et al. [53], & \\ [PERSON] et al. [54], & \\ [PERSON] et al. [9], & \\ Leo Bodnar Electronics [55], & \\ Leo Bodnar Electronics [56], & \\ [PERSON] [57], & \\ NVIDIA [58] & \\ \hline \hline \end{tabular}
\end{table}