Public Key Infrastructure (PKI) and Blockchain

by Amrita Mitra | Mar 9, 2017 | Blockchain, CCNA, CCNP, CompTIA, Data Breaches and Prevention, Data Security, Encryption

Infrastructure can be used with Blockchain.

What is Blockchain?

Blockchain

Blockchain is a distributed database that maintains a continuously growing list of data records that cannot be tampered with.

The blockchain was the main technical innovation behind Bitcoin. In Bitcoin, blockchain is used as a public ledger of all transactions made with Bitcoins.

Blockchain consists of a number of blocks linked to each other. Each block is linked to its previous block. Each block consists of a batch of timestamped transactions and a hash of the previous block. The blocks are linked with each other, forming a chain, hence the name of the database.

When new transactions are broadcast to all nodes, each node collects them in a block. All the nodes verify the transactions present in the block and notify one another about their acceptance. When the majority of the nodes agree, the next block is created and linked to the previous one.

You can get more information on Blockchain here :

How can Blockchain be used in a Decentralized Public Key Infrastructure?

Blockchain can be used in a Decentralized PKI where each block may contain a number of digitally signed transactions. When an entity is registered with a public key, it can sign the public key with its secret key and submit it to the blockchain. All the nodes in the blockchain can participate in the registration, issuance, and validation of the public key of an entity. And, when most of the nodes in the blockchain approve a transaction, it can get added to the next block created.

Registration of a Public Key

When an entity wants to register its public key, it signs it with its secret key and submits it to the blockchain. All the nodes of the blockchain are notified. Each of them then iterates through the blockchain and verifies that the key was not previously registered and that the transaction is valid. When a majority of the nodes verify the transaction successfully, it is approved, and a block miner can add the transaction to the next block created.

Verification of a Public Key

When a user wants to verify whether a public key belongs to the identity, it traverses through the blockchain and looks up the ID and public key pair of each transaction. As each transaction is digitally …

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Amrita Mitra

Author

Ms. Amrita Mitra is an author, who has authored the books “Cryptography And Public Key Infrastructure“, “Web Application Vulnerabilities And Prevention“, “A Guide To Cyber Security” and “Phishing: Detection, Analysis And Prevention“. She is also the founder of Asigosec Technologies, the company that owns The Security Buddy.

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Public Key Infrastructure (PKI) and Blockchain

What is Blockchain?