## 3 System Model and Assumptions  
Our system model is represented by video streaming over HetNet. The HetNet is mainly composed of two components; macrocells and femtocells (cf. Figure 1), where the former provides mobility capability while the latter tries to extend coverage and capacity. The mobile device can be connected to the HetNet first, then the Internet, and finally the cloud computing where video streaming services are located. We assume a centralized Mobile Cloud Computing paradigm as it is the most conventional. The macrocell is controlled by the MBS, which is responsible for regulating traffic in the macrocell, while the small cells are operated by FBSs. Here, a distinction between user equipment, which is connected to MBS as they are called MUEs or Macrocell User Equipment, and the users who are connected to small cells, which are called FUEs or Small User Equipment, is essential [23]. \begin{table}
\begin{tabular}{l l} \hline
**Acronym** & **Meaning** \\ \hline MBS & Macrocell Base Station \\ MCS & Modulation and Coding Scheme \\ MIMO & Multi-Input Multioutput \\ ML & Machine Learning \\ MOS & Mean Opinion Score \\ MUE & Macrocell User Equipment \\ OFDMA & Orthogonal Frequency Division Multiple Access \\ PA & Power Allocation \\ PLC3 DCS & Playback Length Changeable 3D Video Data Chunk Segmentation \\ PLR & Packet Loss Ratio \\ PSNR & Peak Signal-to-Noise Ratio \\ OoE & Quality of Experience \\ QoS & Quality of Service \\ RAN & Radio Access Network \\ RB & Resource Block \\ RSS & Received Signal Strength \\ SDN & Software Defined Network \\ SDQA & Streamlined DP-based Quality-level Allocator \\ SINR & Signal to Interference Noise Ratio \\ SVC & Scalable Video Coding \\ TCP & Transmission Control Protocol \\ TDD & Time Division Duplex \\ UL & Uplink \\ WLAN & Wireless Local Area Network \\ WQUAD & Wireless Quality Adaptation \\ \hline \end{tabular}
\end{table} 
Table 1: _Cont._  
Figure 1: Video streaming system architecture with HetNet. Video streaming over wireless networks faces many challenges due to the nature of the wireless channel, which is time varying and has limited resources in terms of bandwidth, making it hard to guarantee any specific video QoS. However, when considering the context of HetNet, the main problem can be represented by the interference, which influences the quality of video delivered by the network (Table 2 describes all the symbols used in the article with their meaning). In this structure, \(I\) MUEs are uniformly distributed within the MBS coverage area and they are not allowed to access femtocell \(F_{I}\), \((l=1,...,L)\) during their mobile tour, i.e., all the outdoor users are non-CSG users for \(F_{I}\) operators. An \(F_{I}\) covers \(J\) randomly distributed FUEs. The MUEs and FUEs use a common frequency band divided into k RBs with OFDMA-based transmissions. We also assume that the macrocell M is full up and cannot provide any intra-channel allocation to mitigate the probable interference caused to MUEs users. Both M and FBSs need a periodical report as Channel Quality Indicator (CQI). in terms of SINR to check the signal quality of their UEs and provide the resource allocation of their RBs. The receiver DL SINR of a given \(MUE_{i}\), \((i=1,...,I)\) related with M on resource block \(k\) can be defined as: