# First Request First Service Entanglement Routing Scheme for Quantum Networks
## 5 Evaluation Results
### Evaluation on T/W-DM Networks  
The FRFS routing scheme is first evaluated on the topology which originates from the SECOQC QKD network and the Tokyo QKD network and is shown in Figure 5. The entangled photon source (S) is connected to a WSS or DWDM (R\({}_{1}\)). They play the role of quantum server, which assigns the available wavelength channel to users when they request the \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**B** & \(\mathbf{t_{\text{CC}}}\) & \(\mathbf{\eta^{t_{\text{CC}}}}\) & \(\mathbf{e^{pol}}\) & **DCR** & \(\mathbf{loss_{\text{user}}}\) \\ \hline \(5\times 10^{8}\)cps & 300 ps & 0.761 & 1.81\% & 300 cps & 3 dB \\ \hline \hline \end{tabular}
\end{table} 
Table 1: The parameters used in our evaluations. B is the brightness of the entanglement source. \(t_{\text{CC}}\) is the coincidence window and \(\eta^{t_{\text{CC}}}\) is the coincidence-window dependent detection efficiency. \(e^{pol}\) is the individual polarization error probability. DCR is the dark count rate. \(loss_{\text{user}}\) is the internal optical device loss of each user. channel resources. \(\mathrm{R_{2},R_{3},R_{4},R_{5}}\) are four forwarding nodes and the numbers around the node represent the port of the device. A, B, C, and D are users. The current entanglement distribution networks with dynamic topology mainly adopt the time division multiplexing (TDM) technology and wavelength division multiplexing (WDM) technology. In this article, we mainly simulate the TDM network and the TDM \(+\) WDM network by deploying different devices on \(\mathrm{R_{1},R_{2},R_{3},R_{4},R_{5}}\). The detailed configurations of each device are shown in Table 2. The assigned wavelength channels for A and B are CH33 and CH35 respectively. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Case**} & **Network Type** & \multirow{2}{*}{\(\mathbf{R_{1}}\)} & \multirow{2}{*}{\(\mathbf{R_{2}}\)} & \multirow{2}{*}{\(\mathbf{R_{3}}\)} & \multirow{2}{*}{\(\mathbf{R_{4}}\)} & \multirow{2}{*}{\(\mathbf{R_{5}}\)} \\ \hline
1 & TDM & 5 ports & 2\(\times\) 2 & 2\(\times\) 2 & 2\(\times\) 2 & 2\(\times\) 2 \\  & WSS & AOS & AOS & AOS & AOS \\ \hline
2 & TDM & 5 ports & OS\((1/4\)in, & OS\((1/4\)in, & OS\((1/2\)in, & OS\((1/2\)in, \\  & WSS & 2/3 out) & 2/3 out) & 3/4 out) & 3/4 out) \\ \hline
3 & TDM + WDM & 5 ports & 5 ports & 5 ports & 5 ports & 5 ports \\  & WSS & WSS & WSS & WSS & WSS \\ \hline
4 & TDM + WDM & 5 ports & 5 ports & OS\((1/4\)in, & 2\(\times\) 2 & 2\(\times\) 2 \\  & WSS & WSS & 2/3 out) & AOS & AOS \\ \hline
5 & TDM + WDM & \(1\times 4\) & \(1\times 4\) & \(2\times 2\) & \(2\times 2\) & 2\(\times\) 2 \\  & DWDM & DWDM & AOS & AOS & AOS \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Parameters of the forwarding devices in Figure 5 for different configurations. Case 1 and case 2 are TDM networks that are implemented by AOS and OS respectively. Cases 3, 4 and 5 are TDM+WDM networks and adapt the AOS to achieve TDM. The WDM in cases 3 and 4 is implemented by the WSS. In case 3, all devices support the active WDM. In case 4, partial devices (only WSS) support WDM. In case 5, the passive WDM with fixed divided channels is implemented by DWDM. (1/2 in, 3/4 out) indicates that ports 1 and 2 of the device are import ports, and ports 3 and 4 are output ports. The insertion losses of OS, AOS, DWDM and WSS are 0.5 dB, 1 dB, 1.5 dB and 5 dB respectively. The 5 ports WSS can support 16 channels which contains CH26, CH27, \(\cdots\), CH41, CH42. Port 1 of the \(1\times 4\) DWDM (\(\mathrm{R_{1}}\)) is the multiplexing port, and ports 2 to port 5 are demultiplexing ports that support CH32, CH33, CH35, and CH36 respectively. Port 2 of the \(1\times 4\) DWDM (\(\mathrm{R_{2}}\)) is the multiplexing port, and ports 1, ports 4, ports 3 are demultiplexing ports that support CH32, CH33, CH35 respectively. Figure 5: The experimental topology of T/W-DM networks. The entangled photon source (S) is connected to a WSS (\(\mathrm{R_{1}}\)). They play the role of quantum server.