Conclusion

The chapter introduced you to the basics of cryptography—

its strength and

requirement. Cryptography techniques—

cryptology and cryptanalysis are

the disciplines of cryptography. Cipher modes define how the cipher

encrypts and decrypts it. The cipher modes are symmetric, asymmetric,

block, and stream. Digital signatures are used to verify the contents of a

document as also the sender’s identity. The working of digital signatures,

creating a digital signature, digital signature classes: Class 1, Class 2, and

Class 3 , and digital signature uses are discussed. Hash functions are

extremely useful in most of the information security applications. U se of

hash functions in blockchain, hash function security for blockchain, and

types of hash functions are discussed. Digital certificates are a bit of

information that certifies the owner to be genuine. The process of obtaining

a digital certificate is discussed.

The new skills and proficiency you have gained in this chapter about

cryptography will enable you to confidently deal with the topic and put

them to professional use.

In the upcoming chapter, “U nderstanding Distributed Ledger Technology

and Blockchain”, you will be introduced to distributed ledger technology,

which refers to an approach to record and share data across multiple data

stores, allowing for transactions and data to be recorded, shared, and

synchronized across a distributed network of different network participants.

A data structure used in some of the distributed ledgers storing and

transmitting data in packages called “blocks” connected to each other in a

digital chain is a blockchain, using cryptographic and algorithmic methods

to record and synchronize data across a network in an immutable manner.

Keywords

Cryptography: A method of securing messages/ information and

communication through the use of codes so that only those for whom the

message/ information is intended can read and process it.

Ciphertext: It is data that has been encrypted. It is unreadable until it has

been converted into plaintext (decrypted) with a key.

Plain text: A plaintext is an unencrypted message.