## 4 Simulation Setup and Experimental Results
### Discussion  
The important parameters that determine the impact of our proposal are node efficient energy utilization, network lifetime and packet transmission reliability, and secured communication among nodes. With respect to power consumption, it is worth considering that this paper was developed in an agribusiness context where sensors might be operated by a single battery or aided by solar power charging cycles. This context is so particular that the nodes are not distributed with homogeneity in a perfectly isolated area. For defined areas, or plots, where sensors are deployed to collect information about the state of the environment and the crop, for each plot, or for each specified area, we can have a set of nodes. The distribution in farms can be such that we can find different factors such as nodes of other farmers, shadow zones in communications due to adverse weather phenomena, recalibration of any of the sensor nodes due to hostile conditions in which the nodes are deployed, etc. These are, in short, circumstances that invite reconsideration of the dynamic re-election of a head-end (CH) node not only when it drains all its energy. In addition, the possibility of collision with nodes from other plots suggests the use of the proposed cryptographic method to avoid data contamination, together with the reduced power consumption. Finally, an extension to the method based on DLT and IPFS will be proposed to federate sensors into two levels. We will use this technique to guarantee the minimum packet loss in transmissions [32; 41]. Regarding energy: we evaluated the evolution in the draining of energy as long as the algorithm evolves over time. The transmissions from node to node are fixed and the conditions are defined in Table 1. Sensor nodes operating in the field are optimized to gather data and even to synthetize by comprising it into a series. Furthermore, the communication rate is constant, as well as the size of the packet. The amount of energy required to transmit a packet depends on the routing strategy and the packet size. We propose a first approach where nodes are clustered using modified LEACH with a dynamically elected CH and a second proposal where nodes are grouped into two layers: the first one where sensor nodes are light nodes of a DLT and the CH is the one that keeps the log of the DLT; the second one grouping all the CH into a different DLT (second layer of trust where all the logs are shared and the smart contracts are executed for the sake of the packet transmission reliability). Regarding network lifetime, we can consider that the network has expired its lifetime when the CH node has wasted all of its potential energy to transmit data packets or even to receive small control packets. Even though it still has power, we consider it wasted if the operative threshold (oTh) is not met. It is also worth noting that the simulation presented above is applied to a two-dimensional space where the surfaces where nodes are placed are relatively flat. For a surface where there are obstructions and an uneven surface level, a three-model might have sufficed. Packet transmission reliability concerns the number of times that a packet is not acknowledged at its destination or fails to hit its target node over the network. Packet loss in an IoT transmission can be due to a myriad of issues, from farm machinery operating near the nodes in the 2.4 GHz band to DoS attacks preventing nodes from sending data to the CHs. In all cases, packet loss impacts node power consumption. Since as with all radio transmissions (and we do not act on these parameters as it is not the scope of the proposal we present), power is increased if the link is lost. If nodes come under attack, it is easy for an attacker to identify the CH (since it is the destination of all transmissions from nodes in the area) and try to assemble it to bring down the network.