\section{Related Work}\label{related}

Wireless sensor and actor networks are crucial elements of today's effort to support and implement \textit{Industry 4.0} architectures and modern manufacturing processes.
Small programmable logic controllers (PLC) and cloud computing are enabler but also drivers of these new manufacturing paradigms \cite{Nigappa:2016eb}.
Thus, the networked interconnection of everyday objects, the automation of home appliances and environmental metering and monitoring based on sensor and actor networks controlled by ESP-based chipsets are subject of current research.
In \cite{DiNisio:2015fg} a low-cost multipurpose wireless sensor network using \textit{ESP8266} PLCs is introduced.
The usage of \textit{ESP8266} PLCs for sensor networks is discussed in \cite{Thaker:2016fi}.
The article \cite{Kodali:2016hc} presents a home automation solution based on a \textit{MQTT} message queue with \textit{ESP8266}-based sensors and actors.
The control of smart bulbs with PLCs is summarized in \cite{Walia:2016bj}.
Unfortunately, software update mechanisms are not addressed in these publications.
Generic approaches of decentralized software updates in IoT environments are introduced in \cite{Weisbach:2016bs} and \cite{Ruckebusch:2016vo}.
The \textit{Over the Air} programming capabilities of the \textit{ESP8266} PLCs are described in \cite{Gore:2016ue}.