# Intelligent Traffic Engineering for 6G Heterogeneous Transport Networks
## 6 Discussion and Findings
### DL and UL Use Case Results: Transport Assignment Process  
3.1 The Performance of the Cluster-Transport Assignment in Scenario 1 (Dedicated Transport Network to a Single Node in a Service Area)  
This study improved the traffic load proportioning process into multiple transport network types to determine the most efficient assignment. The process was achieved by clustering the traffic based on the UE type or use cases. A similar approach was also applied to this process (see Figure 5). Table 7 displays the proportions of use cases for the UL stream in the dedicated resources of the transport network. Each traffic was grouped based on its classifications and was then assigned using the MILP method. From Table 7, DL and UL traffic sizes are generated within the available link's resources. Similar to the observation from Table 3, PDB and PER values produce values higher and lower than the link's RTT and PER, respectively, thus producing very low scoring to the performance matrix. The high DL traffic is fully assigned to the optical network originating from the eMBB use case traffic type. In contrast, the maximum list of UL traffic from every instance is distributed to two transport network types (optical network and DOCSIS cable). The highly generated upload traffic based on the nature of the mMTC use case results in assignment to the optical network (48.33%), with satellite network handling a minimal percentage of mMTC traffic types (3.33%). On the other hand, the list of minimum UL traffic is assigned to the optical network (see Table 8). \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**No** & **Traffic Type** & **Optical Network: TR1** & **Satellite Network: TR2** & **DOCSIS cable: TR3** \\ \hline
1 & Max DL & 17\% & 77\% & 7\% \\ \hline
2 & Min DL & 47\% & 23\% & 30\% \\ \hline
3 & Max UL & 7\% & 85\% & 8\% \\ \hline
4 & Min UL & 33\% & 15\% & 52\% \\ \hline \hline \end{tabular}
\end{table} 
Table 6: The composition of DL and UL traffic size to the transport network: Scenario 2. \begin{table}
\begin{tabular}{c l c c c} \hline \hline
**No** & \multicolumn{2}{c}{**Clustering Based on Use Cases (eMBB, mMTC, and**} & \multirow{2}{*}{**Performance Matrix**} & \multirow{2}{*}{**DL**} & \multirow{2}{*}{**UL**} \\  & **URLLC) against the Assigned Transport Types** & & & \\ \hline
1 & Total traffic size vs. link capacity & Cluster BW \textless{} Tr Capacity & 100\% & 100\% \\ \hline
2 & Maximum PDB vs. link RTT & Cluster PDB \textless{} Tr RTT & 0\% & 0\% \\ \hline
3 & Minimum PER vs. link PER & Cluster PER \textgreater{} Tr PER & 0\% & 33\% \\ \hline \hline \end{tabular}
\end{table} 
Table 7: The performance of the clustering process (use case): Scenario 1. 3.2 The Performance of the Cluster-Transport Assignment in Scenario 2 (A Shared Transport Network in an Area with Multiple Service Nodes)  
Table 9 depicts the use case transport assignment for UL streams containing shared transport resources, in which the net available optical network is used to accommodate traffic from other nodes. Nonetheless, each cluster formed from the use cases shows traffic size within the available resources except in 13% of the total instances where clusters produced higher UL traffic size than the link's capacity. The time parameters show full compliance within the full round-trip time of links. Notably, Table 10 explains the assignment of high DL traffic shifting towards the next highest link's capacity because a low and exhaustive capacity of the optical network was observed in several instances. The eMBB and mMTC generated high and low UL traffic and the assignment to the satellite network and DOCSIS cable transport options, respectively. Elaborating on UL traffic from Table 10, a shift from assigning the mMTC and URLLC traffic across all available transport options can be observed. This finding was attributed to the satellite network capacity consumed by most of the UL traffic from both maximum and minimum lists of UL values.