# Smart Factory Web--A Blueprint Architecture for Open Marketplaces for Industrial Production
## 5 Smart Factory Web Approach
### Search for Production Capabilities
#### 5.4.2 Search for Factories and Factory Combinations (Supply Chains)  
The search for capabilities, production and process steps (Bill of Process BOP) is becoming increasingly important for industrial production marketplaces. Complex, mostly in-house production processes could thus be planned and coordinated across factory boundaries. In addition, collaboration along the entire value chain can be improved and optimized.  
The SFW platform provides a web service interface for searching for factories and factory combinations (supply chains) for the required production process.  
Figure 8 shows the search flow between a requester, a broker and a provider. Service requesters submit a search request to the SFW platform via the GUI or via web service. The SFW platform processes the request and sends the search result back to the service requester. The goal of the search is to find all factories and factory combinations (supply  
Figure 7: Basic CPN for computer mouse manufacture.  
chains) that offer the required capabilities/production steps. The result can be individual factories or factory combinations (supply chains) that fulfill the entire production process. JSON is used to define the search query and the search result. The search query is specified in Figure 9 and is based on the defined data model in Figure 5.  
The search query enables the search for capabilities and therefore also for production and process steps.  
* Capability (of an asset) is described in terms of its input and output products and their respective properties, and/or in terms of how the product can be produced. The capability concept enables the modeling of process steps (BOP Bill of Process, e.g., manufacturing processes for the production of a product). The capability description is comprised of the three sections covering (1) the properties of the production process itself, (2) the input products and their properties and (3) the output products and their properties.
* Product: The product structure (BOM Bill of Material) for both input and output products.  
Figure 8: Search interface of the Smart Factory Web platform.  
Figure 9: Search query specification.  
Property: The property concept is used to describe capabilities and products in more detail.  
The search is started via the SFW search interface by submitting a search query. The search looks for all factories and factory combinations (supply chains) that fulfill the capabilities/production steps defined in the search query. The search procedure is conducted in three steps as follows:  
1. Search for factories that possess the requested capabilities: For each capability or process step searched, a list of all factories is generated that possess this capability, including constraints regarding properties and input/output products, or that can execute the production step.
2. Generate Cartesian product: Then, the Cartesian product of these factory sets is generated to obtain all possible factory combinations (supply chains).
3. Merge factory combinations: In the last step, these supply chains are merged once again. Thereby, factories with several capabilities are identified and the supply chain is simplified (see Figure 10).