## 3 Blockchain for Supply Chain: Fundamentals  
### Supply Chain Process Management  
We can view a supply chain as an organized and systematic network between a company and its suppliers to manufacture and sell a particular product to the final customer, aimed at reducing costs and being competitive in the market. It consists of different processes, data and information flows, people, entities, and other resources. Simply, supply chain covers all the stages and entities involved in delivering a product from its original state to the final customer, starting from supplying and transforming raw materials into a manufactured product, moving the product in the market, and distributing them to the final customer. Overall, supply chain processes rotate in-between five entities including suppliers, manufacturer, distributors, Retailers, and consumers, as shown in Figure 2. Every entity in the supply chain delivers items to another entity against the agreed terms and payments. In modern supply-chain management systems, these agreements, payments, and deliveries are facilitated by blockchains.  
Effective management is crucial to realize optimized supply chain processes, achieving reduced costs and a rapid production cycle. Supply chain management consists of wide range of functions, covering numerous areas. Several supply chain management models exist in the market, varying the number of functions offered. Supply Chain Council developed one of the widely used and more effective model, called Supply chain operations reference (SCOR) model [7], with the help of top-seventy manufacturing firms across the world. SCOR effectively guides managers to tackle, refine, and disseminate supply chain management practices using five primary stages, including plan, source, make, deliver, and return.  
Planning focuses on the analysis of demand and corresponding supply options. It involves various operational strategies and decisions to improve supply chain process effectively, such as balancing resources, determining communication along the entire chain, determining suppliers, determining business rules related to inventory, transportation, and assets, etc. At this stage, it is ensured that the supply chain plan is aligned with the company's financial plan. Next, at'source' stage of supply chain, meters related to procurement of raw materials and components are handled. Sources are assessed and selected, contracts are being negotiated between companies and suppliers, and deliveries are scheduled. In short, it involves the management of inventory, the supplier network, agreements, performance, payments, and scheduling of the entire process from the material reception and verification to its delivery. The third stage'make' entails the management of production activities like, constructing, packaging, assembling, and releasing. It also  
Figure 1: Statistics of the covered literature.  
facilities the records of production network, assets and facilities, and transport. The 'deliver' stage cares about all the aspects of customer orders, warehousing, inventories, and delivery-transport. It manages orders collections from customers and invoicing them after product delivery. In addition, it also manages records of warranty and trial periods (if any), retail sites invoicing and payments, and import and export requirements of the manufactured product. Finally, the'return' stage deals with the return aspects of the product, including return of containers, packages, defective product, inventory, assets, and transportation, and the related business rules and regulatory requirements. A BC-SCM system implements these stages (fully or partially) using a blockchain and smart contracts.