## 1 Introduction
### FiWi Network Architecture  
A hierarchical clustering method using a topology-type tree will be used in this paper. This method is a fundamental operation in the deployment of SMs [33; 34]. The paper from [35] stated that an optimal conformation of the clusters is determinant in order to minimize the end to end delays of each cluster. The knowledge of the end to end delays in a wireless network can be used to deduce the available bandwidth. There are some techniques based on the observation of the delays to detect the point at which the delays begin to increase and, in this way, to determine the bandwidth. The results show that it is feasible to obtain reliable estimates under certain circumstances, such as: different packet sizes, wireless link speeds and channel noise [36; 37; 38]. Therefore, in the present paper, the bandwidth is considered through the delays, not as a restriction of the problem, but as a parameter that can be calculated to size the equipment and achieve a robust wireless communication network that guarantees the transmission of the information in a safe and reliable way. Finally, the required bandwidth depends on: the packets transmitted from a source node to a destination node, the traffic they generate, the frequency at which they are transmitted, the point-to-point distance and the number of jumps. Therefore, the maximum data transfer range of a physical communication link is proportional to its bandwidth [39; 40]. There are two types of hierarchical groupings: binder and divisive [41; 42]. The binder method starts by placing each object in its respective cluster and then merging the groups into larger clusters, until all the objects are in a unique cluster or certain conditions are met. The divisive hierarchical grouping method is not limited to grouping into a balanced cluster or into a cluster of the same length, as some conventional methods do. Some of these conventional clustering methods are k-means, k-medoids and mean-shift [43]. In the present paper, we will form clusters using the binder method. This is a method that allows us to balance the length of the clusters and minimize certain parameters of a communications network such as: end to end delay, FSPL and the ability to link. In the clustering techniques, the SMs are organized into groups. The regular SMs are called cluster members, and a head is selected from the group tagged as the Universal Data Aggregation Point (UDAP). There are three types of generated traffic: intra-cluster, inter-cluster and the existing traffic generated by base stations (BS) toward the central office [29; 44; 45; 46]. These are illustrated in Figure 1 through the use of optical fiber. The members of a cluster cannot send data directly to the BSs, since the UDAP receives data from the SMs members of the cluster, eliminates redundant data and merges the data with the objective of transmitting to the respective BSs. This paper considers a FiWi network [47] in two stages: The first stage describes a wireless hybrid network [48; 49] that articulates cellular technology and WiFi to transport the information from the SMs to the BSs passing by a node of transition UDAP capable of supporting both technologies. This will ensure efficient and effective two-way communications within standardized parameters for the communication [47; 50; 51; 52]. In the second stage, data are merged in the BSs using optical fiber. Following that, a backhaul will be added to transmit the information to the central offices or information management centers. The properties of the UDAP allow receiving data from the SM members of the conglomerate. Following that, it merges the data and transmits the added information to the BSs. A UDAP is an SM with double availability for cellular and WiFi wireless access. In summary, we make the following contributions in this paper: (1) the proposed heuristic focuses on minimizing the data aggregation cost. This heuristic uses a hierarchical topology capable of reducing transmission delays, contributing directly to minimizing link capacity [53].