# The Shared Bicycle and Its Network--Internet of Shared Bicycle (IoSB): A Review and Survey
## 2 Background  
### History  
The shared bicycle, also called bicycle-sharing in some references [11; 17; 18; 19], is about 55 years old and has four generations as far as we know. Especially in recent years, the shared bicycle are flourishing in smart cities, and most of them are successful. Table 2 shows the progress of shared bicycle. \begin{table}
\begin{tabular}{c c} \hline \hline
**Transport Method** & **Carbon Emission (gCO2/Km/One Person)** \\ \hline Private Car & 501 \\ Taxi & 167 \\ Metro & 60 \\ Bus & 20 \\ Shared Bicycle & 0 \\ Walk & 0 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Carbon emissions of different transport methods [14; 15]. Figure 3: Comparison among different transport methods in urban area [11]. The first generation shared bicycle was firstly introduced in 1965, which provided free bicycles to borrow and return from any location [11]. However, since the fact that the shared bicycle were often stolen or damaged by users, it seemed the safety became a big problem to shared bicycle, which would prevent the further development and raise the maintenance cost obviously [18]. In 1995, the second generation shared bicycle was born in Copenhagen (called Bycyklen or City Bikes [11]) with many improvements over the previous generation. The bicycle consisted of solid rubber tires and wheels, and could be borrowed and returned from any self-service bicycle station throughout the city with coin or smart cards access [17]. The bicycles of this generation were equipped with a docking station, which is the prototype of the modern public bicycles. Shared bicycle of the third generation appeared in 2006. In this generation, Global Positioning System (GPS) was utilized to provide the reasonable locations, which was helpful for better tracking of bikes [17]. Another innovation was recording the riding time and provide it to users at specific station with the help of the new network and information service [11; 24]. In addition, combined with Geographic Information System (GIS) [21], the distribution of bicycle can be analyzed and the plan of bicycle scheduling could be simpler. With the possibility of networking and information service, this generation alleviated or solved some problems. For example, it was possible to get users' information before lending the bicycles, and some related companies were able to check the user's historical transaction. In 2009, some operators used a networked bicycle station and RFID technology to monitor the geographical location of shared bicycles (New York City Department of City Planning, 2009) [11]. With the introducing of many new technologies, the shared bicycle of the fourth generation, which is considered to be one type of intelligent hardware, developed so quickly in recent years. Especially with the emergence of sharing economy like Uber in 2010 [31], the public bicycle, which had not been developed smoothly in many cities these years, was becoming popular in a new mode called bicycle-sharing. In April 2016, Mobike launched its smart bike sharing service in Shanghai, which is an attempt to extend the mobile payments to shared bicycle [32]. It is easy to unlock the shared bicycle using QR-code for citizens. In July 2017, another bicycle-sharing brand OFO, along with China telecom and Huawei, launched their smart lock equipped with an Narrow Band Internet of Things (NB-IoT) module [33]. The introduction of NB-IoT technology [34] is expected to greatly reduce the energy consumption of bicycle-sharing system. In addition, there are also some related works on the analysis of big data generated by bicycle cycling. For example, the authors in [35] used crowdsourced data from bicycle-sharing system to analyze the relationship between different cycling purposes and air pollution exposure. The results shows that cyclists riding for recreation and other purposes tend