## 4 Implementation of the BBSM Concept in the Virtual Environment
### Design of the BBSM Virtual Environment  
The BBSM concept in the virtual environment was mapped by implementing the five main properties of the BBSM system that distinguish it from any other blockchain-based system or manufacturing mode. **Service-oriented manufacturing:** The BBSM system involves service-oriented manufacturing in which individual APUs offer their unused resources on the market to increase the utilization of their capacities [1]. In the developed game, these unused capacities are mapped in the form of services offered by APUs on the market (Figure 2). The APUs, which are represented by the players, can offer their service to other players with a certain frequency (\(\hat{f}_{service}\)). The offer is defined by the type of service offered by the provider, the price set for the service, and the time required to perform the service. Figure 1: Methodology employed for the analysis. Services are exchanged in the form of a free market where prices are self-regulated by the sellers' response to a customer's demand [54]. The medium of exchange is virtual money that is equally distributed at the beginning of the game. All services that are bought by other players in the implemented system are executed automatically due to the simplification of the system. In the BBSM concept, virtualized manufacturing resources are connected with the social representation of the APUs on the market. In this analysis, an assumption is made that all manufacturing resources are already available in the virtual layer of the system due to the simplification of the system. In this virtual implementation of the system, physical activities are modeled only by production time. **Prosumers:** The operational model of BBSM permits individuals and enterprises to act as both providers and consumers of services, becoming prosumers [1]. There are three types of services in the game (services A, B, and C), one of which is predetermined to each APU. The APUs can provide their service and consume other services on the market that are not of the same type as the one they are providing. Examples of types of services are provided to the players for each service type for better understanding of the game. The divided groups of players (three types) represent a group of companies that are specialized in the field of mechanical engineering, electrical engineering, and IT engineering. An assumption is made that all companies of the same type have the same knowledge of the field of service they are offering (e.g., all mechanical engineers are equally good or close to equally good at mechanical services). Therefore, manufacturers within each group do not require services from other companies to improve their manufacturing services. However, by purchasing other types of services, they can increase their manufacturing capabilities. The presented analysis is focused on the effects of the scalability limitations of blockchain technology on the BBSM. Therefore, the observed phenomenon is congestion of the blockchain network (i.e., the network is not capable of processing new transactions with the same frequency as they are created). Congestion of the blockchain network in the BBSM system can occur if the frequency of the service exchange surpasses the frequency of transaction confirmation. One of the possible scenarios in which such a situation would occur in reality the case of increasing customer demand, which is an open issue addressed by global manufacturing systems. In the implemented system, growing customer demand was incurred through an incentive scheme in which the primary criteria for determining the winner was the development of the production system. To fulfill increasing customer  
Figure 2: Online game implementation of BBSM system. demand, additional manufacturers in the system or more optimized utilization of existing capacities is required.