## 1 Introduction  
Modern closed heinhouses mostly adopt a multilayer cage rearing system with a high breeding density. Besides relying on technological advances in breeding and rearing, modern heinhouses impose high requirements on the henhouse environment. Of all the parameters, temperature, humidity, CO\({}_{2}\) concentration and NH\({}_{3}\) concentration are especially important for chicken health [1]. Modern monitoring technologies can provide a scientific management basis for henhouse managers and help to raise management efficiency and lower production costs [2].  
The Internet of Things (IoT) is a new information technology and the network of things that are connected to the Internet through corresponding sensing devices to enable data acquisition, fusion and processing and allow intelligent identification and management at the operating terminal. IoT is widely applied in fields like modern greenhouse environmental monitoring [3,4], agricultural product tracing [5], smart city [6], livestock and poultry farm environmental monitoring. For livestock and poultry farm environmental monitoring, [7] reported that AVR controllers were used to monitor the temperature, humidity, CO\({}_{2}\) concentration and NH\({}_{3}\) concentration inside a henhouse, the configuration software LabVIEW was used to design visual application software, and fuzzy control was used to regulate the temperature, humidity, CO\({}_{2}\) concentration and NH\({}_{3}\) concentration inside the henhouse. It is documented that for the structure of traditional heinhouses, a remote environmental monitoring system was developed based on ARM and Zigbee technologies in [8]. As a result, labor intensity was lowered and work efficiency was raised. It was reported in [9] that temperature inside heinhouses was monitored and GPRS technology was used to realize overlimit short-message warning. In [10], CC2430 was used to design a wireless sensor network to collect data of temperature, humidity and CO\({}_{2}\) concentration inside a poultry house. Consequently, wireless data acquisition was realized and system cost and maintenance difficulty were lowered compared with wired data acquisition.  
In summary, henhouse environmental monitoring systems based on IoT technology are popular among users because it is networking with no need of wiring and it is of low updating and maintenance costs [11,12]. However, previous studies mainly focused on system design with little attention paid to the reliable transmission of wireless data. In fact, equipment like hencoops of steel-frame structure in heinhouses cause great interference to the wireless data transmission of multiple sensors such as data duplicated and data missed. What is more, henhouse environmental monitoring systems based on IoT are yet to be widely applied [13,14]. In this study, a wireless transport protocol based on a loss recovery strategy was proposed to address the issue of data packet dropout during wireless transmission so that the practicability and reliability of such henhouse monitoring systems can be enhanced. In addition, duplicated data auto-filtering and missing data online filling were achieved. In view of the requirement of remote mobile monitoring, a Web remote monitoring system was designed. Authorized users could access the monitoring information through a PC or a mobile smart terminal. Remote monitoring and management of the henhouse environment were thus realized through a simple and friendly interactive interface, and with higher management efficiency.