Securing Blockchain Networks like Ethereum and Hyperledger Fabric

Symmetric cryptography limitations

The main weakness of symmetric cryptography is the management of encryption keys (also known as the key distribution problem). Since symmetric cryptography makes use of the same key to perform both the encryption and decryption processes, to establish reserved communication channels with multiple different counterparties we must, therefore, create and assign a different key to each individual counterpart. Consequently, the management of symmetric encryption keys does not scale well in distributed network contexts.

To realize this, it is sufficient to consider that in a network of n nodes, it would be necessary to create, distribute, and manage n(n – 1)/2 different key pairs. Anyone who discovers the key ...