Cryptography

Cryptography is the practice of disguising information in a way that looks random. This episode explores the history of cryptography and how it has evolved into the complex systems today.

Data are not all the same. Whether data are at rest, in use, or in transit will affect how you can best secure it.

This episode introduces various methods used to protect the critical keys in cryptography that keep communication secure.

In this episode, Mike describes encrypting and decrypting data with the same key. He also covers how symmetric algorithms can either be block or streaming and use various types of ciphers depending on which one is used.

Symmetric block algorithms have limitations depending on which kind of cipher is used. This episode explores the different block modes.

In this episode, Mike describes encrypting and decrypting data with different keys and the magic that happens when key pairs are generated.

Learn the Diffie-Hellman key exchange agreement and methods in this very complex algorithm.

Hashes provide assurance of data integrity using fascinating mathematical calculations. Passwords are a very common use for hashing.

Digital certificates are used in many different places to verify the identity of a public key owner. They can also include verification from third parties for an added layer of security.

Web of trust is a mostly outdated method of proving identities; however, it is helpful to understand as the predecessor of public key infrastructure (PKI) which is widely used today.

In this episode, Mike discusses public key infrastructure (PKI), used to enable commerce and other secure activities over the Internet.

Mike reviews different types of certificates including Web, e-mail, code-signing, machine/computer, and user.

Mike tours various certificates in this episode.

In this episode, Mike explains how encrypted information is at risk and explores ways to protect it.

Passwords are often stored in hash format but can still be susceptible to attacks. The various password attacks include brute force, dictionary, and rainbow table. Salting and key stretching add another layer of security to hashed passwords.

Dan demonstrates how to use a password cracking tool to turn hashed passwords into cleartext.

Protecting sensitive data can be done using many techniques. In this episode , the viewer is tested on the best security control for a given scenario.

Multifactor authentication should always be used for administrative accounts. In this demo, SSH public key authentication is configured for a Linux host.

Digital cryptocurrencies provide a centralized public way to pay for goods and services. This video explains the relationship between cryptocurrency, public ledgers and the blockchain.

When using the Internet, users retrieve or share information. Depending on the application, purpose, and implementation methods, the need to provide data confidentiality, integrity, and authenticity emerges. To ensure these requirements are fulfilled and that only authorized parties have access to the data, the information transmitted over the Internet is obfuscated.