# A Review of Industry 4.0 Manufacturing Process Security Risks
## 1 Introduction  
Since the dawn of the first industrial revolution in the eighteenth century, there has been continual development in all areas of the manufacturing industry. The first industrial revolution stemmed from the first innovations in industrial machinery (such as the steam engine) that enabled large-scale manufacturing and mechanization. The second industrial revolution followed. With the invention of electricity that could be utilized to develop new infrastructure that could further expand upon industrial capacity, the second industrial revolution occurred during the late nineteenth century to the early twentieth. The third industrial revolution was caused by the invention of computers in the 1950s. The introduction of computers in the industrial context led to many new possibilities in terms of process automation and optimization [1; 2]. Although these past revolutions had enormous ramifications in the industrial sector, we have now arrived at what is arguably the most prominent and disruptive phase of the manufacturing industry that has ever taken place. Industry 4.0, denoting this new phase as the \"fourth industrial revolution\", has already become a buzzword in industrial manufacturing circles. This new phase in the manufacturing industry is rapidly expanding, with the introduction of new and innovative technologies designed to provide more cost-effective, robust and efficient solutions to manufacturing paradigms [1]. One of the most prominent of these new technologies is 3D printing. As an additive manufacturing process, 3D printing has made it possible for manufacturers to produce complex products at a fraction of the manufacturing cost that conventional manufacturing methods would entail. At the same time, 3D printing offers a production efficiency that is orders of magnitude higher than conventional manufacturing processes [1; 3]. Another driving force of Industry 4.0 is the Internet of Things (IoT) movement, which involves interconnecting various digital and electronic devices and platforms through communications networks, particularly through the Internet. This method of interconnecting various technological platforms presents the ability to interface with manufacturing equipment located anywhere in the world, from anywhere in the world. As a result, product designers are able to send product designs for manufacturing to an ever-growing list of possible manufacturing houses, causing a transformation of the manufacturing industry where a more flexible yet optimized production environment is presented. In a study conducted between April 2012 and January 2014, titled Project SHINE (short for \"SHodan INtelligence Extraction\"), the number of manufacturing devices deployed in control systems environments connected to the Internet (either intentionally or unintentionally) were already in excess of 500,000. At a reported average rate of 2000 to 8000 new devices detected on a daily basis, one can only imagine the sheer magnitude of Internet-connected devices that are present in these environments today [3; 4]. In fact, according to a press release by Gartner, the number of IoT devices in use around the world is estimated to reach in excess of 20.4 billion devices in 2020 [5]. As a result of this growing trend, some industries and government bodies have already started acting towards exploring, researching and developing new strategies and technologies to address the needs of such a trend. For example, a resolution on developing an integrated industrial digitalization strategy for the European Union (EU) was already adopted by the European Parliament in June 2017 [6]. As disruptive and innovative as 3D printing in Industry 4.0 is, there is paramount concern about the cyber-security aspects involved. Industries around the world are all too familiar with the risks involved if proper digital security measures are not in place. For example, industrial espionage and industrial sabotage are very real concerns for industries where sensitive and proprietary data could be exposed or even destroyed.