# Highest Cost First-Based QoS Mapping Scheme for Fiber Wireless Architecture
## 5 Simulation Setup and Results  
We have developed a testbed based on XGPON and the pre-existing fifth generation Wi-Fi (802.11 ac) module using the INET 4.2 framework and OMNET++5.5 following References [22; 43]. The simulation comprises a single OLT, one splitter, and eight ONUs at 20 km with 10 Gbps US and 10 Gbps DS, as shown in Figure 7. The PON acts as the optical back-end, wherein a 1:1 integrand of ONUs with wireless access points (WAPs) is designed through Ethernet links of 1.2 Gbps line rate. The wireless access points are equipped with both wired and radio interfaces. STAs are connected to the WAP to create single-hop communication, where each STA generates different wireless traffic (i.e., video, voice, best effort, and background) with UDP to the WAP for FiWi traffic. Both WAP and STA use the 40 MHz channel model of Task Group n (TGn) at a 5 GHz frequency band with eight numbers of the spatial stream (NSS). The physical data rate of STA is 1.2 Gbps at the wireless side. STA nodes are randomly distributed in an area of 3000 \(\times\) 3000 m. Table 3 summarizes the numerical simulation parameters for the proposed FiWi access network. Figure 6: Functional flowchart of proposed FiWi access network. The wireless station generates UDP traffic using Poisson distribution. We use an exponential function for generating the Poisson distribution-based traffic for all WLAN stations. Equation (6) \begin{table}
\begin{tabular}{c c} \hline \hline
**Simulation Parameters** & **Values** \\ \hline IEEE 802.11 ac MAC Mode & DCF and EDCA \\ Operating Frequency & 5 GHz \\ Channel Bandwidth & 40 MHz \\ Bitrate & 1.2 Gbps \\ Traffic Model & Poisson Distribution \\ Modulation (Tx and Rx) & QAM-16 \\ Forward Error Correction FEC coding rate & 3/4 \\ Power Tx and Rx & 4 mW \\ Rx SNIR Threshold & 10 dB \\ WLAN & Rx Sensitivity & -86 dBm \\ BlockAck Supported & True in EDCA \\ Queue Size & 1000 packets \\ Max MPDU & 65,535 Octets \\ RTS Threshold & 100 Bytes(B) \\ Message Length (BE, BK, VI, and VO) & Uniform (64 B, 1472 B), Uniform (128 B, 1024 B), 1024 B), and 160 B \\ Transport Protocol & User Datagram Protocol (UDP) \\ CWmin and CWmax & 3 and 1023 \\ SlotTime and SifsTime & 9 and 16 μs \\ Number of AP: STA & 8:8 \\ \hline \multirow{7}{*}{XGPON} & Number of OLT:ONU \\  & TCONT-1 Bandwidth \\ \cline{1-1}  & TCONT-2 Bandwidth \\ \cline{1-1}  & TCONT-3 Bandwidth Assured \\ \cline{1-1}  & TCONT-3 Bandwidth Surplus \\ \cline{1-1}  & TCONT-4 Bandwidth \\ \cline{1-1}  & ONU Queue Size & 2 MB \\ \cline{1-1}  & DBA Scheme \\ \cline{1-1}  & DBA Cycle Time \\ \cline{1-1}  & US and DS Line rate & 10 Gbps \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Simulation parameters. Figure 7: Simulation setup for FiWi network in OMNET++. shows the traffic arrival rate (\(\lambda\)) computation for the traffic generator configured for each ONU. Where, the physical WLAN data rate (WRate) with the set value of 1.2 Gbps is converted into bytes and then divided by framerate (\(\sigma\)) to yield the number of frames for US transmission in the FiWi access network. Framerate (\(\sigma\)) is the average value of message length in bytes and has a distinct value for each of 04 classes. Traffic-load varies from 0.1 to 1.0. Since OMNET is a discrete event simulator, the sending interval (SI) event, inter-arrival time, is controlled by a timer and is computed using Equation (7) [44]. \[\lambda=((\text{WRate/8})/\sigma)\times\text{Traffic-Load} \tag{6}\]  
\[\text{SI}=\text{e}^{-1/\lambda} \tag{7}\]  
End-to-End Delay (\(\text{EE}_{\text{Delay}}\)) is an overall delay time that \(\text{n}^{\text{th}}\) packets encounter from wireless STA to a server, given in Equation (8), where \(\text{AT}_{\text{N}}\) is the arrival time of \(\text{n}^{\text{th}}\) packet at the destination, GTN is generating time of the \(\text{n}^{\text{th}}\) packet, and \(\text{TT}_{\text{N}}\) is the transmitting time of the \(\text{n}^{\text{th}}\) packet at STA.