Blockchain Essentials

As a young student of physics, I loved to read Antoine de Saint-Exupéry. Now working in the SAP Innovation Center Network on Blockchain for several years, he is the one who provides the perfect quote for this blog:

Antoine de SaintExupéry — ‘Perfection is achieved, not when there is nothing more to add, but when there is nothing left to take away.’

The essential Blockchain capabilities that you cannot take away are immutable timestamps and public keys. This blog will explain these capabilities.

Immutable Timestamps

There are several apps available to store hashes of images on the blockchain. In these apps, you upload a photo. The app calculates the hash of the photo and stores it on blockchain.

One use case is documentation of a rental car damage before starting the trip:  You take a photo of the damages and the hash of the photo is stored on the blockchain. When returning the car and discussing about damages, you could show the timestamp on blockchain to prove that the photo was taken when picking up the car.

Essential blockchain capability 1: An immutable timestamp created by the Blockchain.

Public Keys

Think of your bank accounts IBAN. If I know your IBAN and ask your bank to give me your money, they will not do it. There is a relation between the IBAN and your ID, e.g. in Germany by POSTIDENT or by online video checks.

In Blockchain, the IBAN is called address or account. The relation between you and your Blockchain account is done by using public and private key Key encryption. Typically this is handled by so called Wallets. You create the public and private key pair on your own and keep the private key as a secret. When interacting with the Blockchain, you (or your Wallet) signs all entries with your private key.

If someone asks you to prove that you own an account, you can send a message signed by your private Key.

Essential blockchain capability 2: Your Public Key (account) with your private key.

That’s all. Sounds a bit boring and it’s time to see the two capabilities in action:

Blockchain in Action

The Hash Apps

First let’s take an app from above which stores hashes on the blockchain. This app only needs the Immutable Timestamps capability.

In Blockchain, the interactions with the Blockchain are called Transactions. The transaction of the app is the storage of a hash. As hashes are unique, searching for the hash will find the transaction and show the timestamp of the transaction. The transaction is created by the public key of the app.

The Bitcoin transfer

Let’s assume Jane owns Bitcoins and wants to transfer 1 Bitcoin to Robert. Jane has a Bitcoin account and her wallet knows the Public-/Private Key pair. The Wallet will create a Blockchain transaction containing the amount and the account of Robert and signing it with the public and private key pair of Jane.

When Roberts wants to know his Bitcoin balance, all transactions to and from his account are used to calculate the balance.

Your “Blockchain in Action” Use Cases

As a guideline, please assume that the two Essential Blockchain Capabilities are available as a standard in the Internet and you can use a wallet to access the capabilities. Imagine your business card shows your public key.

Now it’s time for you to be creative. What are your use cases for Blockchain? Where do you need Imutable Timestamps and Public Keys?

Please feel free to post any questions regarding this topic in the Blockchain community or approach us directly:

Frank Albrecht (Developer, SAP Innovation Center Network)