# An Internet of Things-Based Low-Power Integrated Beekeeping Safety and Conditions Monitoring System
## 2 Related Work on Internet of Things (IoT) Beehive Incident Response and Management Systems
### IBSMC Communication Protocols  
IoT communication protocols in agriculture utilize a minimum three OSI model layer logic. That is, a perception layer than implements the sensors-transponder (end node logic), on top of this a network layer responsible for machine-to-machine communication and node-to-concentrator coordination and the application layer maintaining the M2M communication protocols [3]. Other IoT protocols, such as ZigBee [39] or IEEE 802.15.4 [48] use a more complex communication model that utilizes separate network (IPv6) and transport layers. Such wireless devices can either communicate with a central concentrator node, or router or getaway, or even with each other following a mesh network communication approach [13]. Multi-layer architectures can scale and perform well in city environments, where an uninterruptible power supply is available and dense sensor placement is maintained. In agricultural environments where the energy consumption is a critical factor, and there is a sparse sensors placement, simplified communication strategies and three-layer strategies are preferred. Focusing on the IBSMC system proposed in this paper, the three-layer OSI model has been used. Transfer of hives condition data and alerts of security-critical conditions from the automated beehives to the central hive are performed using a two-fold wireless sensor technology. The first part includes the short-range communication of the beehives to the central hive point of control and the second part includes long-range data uplinks with feedback control of the concentrated beehive array data from the central hive via the LoRaWAN gateway to the ISMCA system. Within the proposed IBSMC system, the most efficient close-range technology has been selected among the transceivers 2.4 GHz ZigBee, BLE and 433 MHz RFM12B and RFM69 transponders, having in mind the requirements of close range (less than 50 m all hives from the central hive), low throughput (no more than 50 Bytes of payload) and low energy consumption - low transponder-transmitted power (0-3 dBm), so as to ensure both bees' healthy RF interference environment and beehives' battery long life. According to the previous requirements, a relative RF technology evaluation has been issued by the author of Reference [49] and the RFM12B 433 MHz transponders have been selected [31] for the communication between the automated beehives and the central hive. In case of higher distances (no more than 200 m distance between beehives and the central beehive), the 13 dBm RFM69 FSK modules can be used, using the same payload structure. The protocol selected for as a MAC communication protocol was the JeeLabs library and RF-MAC protocol [50]. Specifically, the IBSMC communication protocols involve three types of M2M communication and data exchange:  
**Type 1: Communication between each automated beehive and the central beehive. ** Beehives sensory data are being transmitted using the beehive sensors application protocol implemented on top of JeeLabs library MAC frames [50] with similar functionality and states to the RF-Tania SDTP protocol. The RF-Tania protocols are comprised of three layers (physical, data-link, application), according to the OSI model. The physical layer includes a Frequency-Shift Keying (FSK) data transmission (RF12B transponders). The Data link layer consists of the JeeLabs MAC layer frames. The application layer includes a frame structure similar to the RF-Tania application protocol for sensory data transmissions and critical incidents transmissions for RF12 transponders [51; 52]. The beehive sensors application protocol is illustrated in Figure 3. Beehive sensory data transmissions are sent to the central hive without acknowledgements for energy conservation purposes, unless there is a notification or alert incident trigger. In such cases, the frames sent to the central hive request frame reception acknowledgements, and if no ACK is received, a six-times frame retransmission process initiates.