Two key cryptographic concepts are

1. Public-key cryptography, or asymmetric cryptography
2. Hashing

A combination of hashing and encryption are used for securing the various elements of the block chain. Private public key pair and hashing are important foundational concepts in decentralized networks that operate beyond trust boundaries.

Transaction Integrity

To manage the integrity of a transaction we need

1. secure a unique account address. We need a standard approach to uniquely identify the participants in the decentralized network.
2. authorization of the transaction by the sender through digital signing.
3. verification that the content of that transaction is not modified.

Addresses of accounts are generated using public key, private key pair. The address is shorter in size, only 20 bytes or 160 bits.