​Blockchain for Smart Healthcare

Introduction

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In 2013, the US Congress passed the Drug Supply Chain Security Act, calling for a new system to follow the movement of pharmaceutical drugs as they flow through the supply chain. We are also concerned with storing the results of drug tests conducted by pharmaceutical manufacturers on the various batches of various drugs they produce. The system we develop should be able to store these results and link them to the many containers of drugs moving through the supply chain while maintaining the privacy of certain data and transactions. We believe that blockchain technology contains many beneficial attributes that will streamline and simplify this process for all relevant parties.

What is Blockchain?

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In simple words, a blockchain is "a continuously growing list of records linked and secured using cryptography." Essentially a chain of blocks, each block contains transactions made between entities and information such as a timestamp and a hash pointer to the previous block. Because hash functions produce unique hashes for the most part, we know that there could have only be one specific block the hash pointer was pointing to, and this type of chaining prevents people from easily changing the important contents (transactions) recorded by the blockchain.

Within a blockchain network, multiple connected nodes receive transactions placed by users, and it is the nodes' jobs to propagate and order these transactions. Each node will come up with their own block to propose as the next block in the blockchain, but how do we come to a consensus on which block to choose?

• Proof of work: Each node must solve a cryptographic puzzle regarding their block, and the first one to do so wins
  
• Proof of stake: The more assets in a network a node is willing to stake, the more likely their block will be chosen
  
• Random choice
  
• Third-party consensus systems
  

Hyperledger Fabric

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Main Concept

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