In this section of the course,
we're going to discuss advanced cryptographic concepts.
The advanced cryptographic concept section
of the course focuses on Domain 3, security engineering,
specifically Objective 3.7,
which states that you must be able to explain the importance
of advanced cryptographic concepts.
Understanding advanced cryptographic concepts is essential
to protect sensitive data from complex and evolving threats.
Managing encryption keys
and selecting the right encryption techniques
are the first vital steps in this process.
However, as technology advances,
considerations around security
and performance become more intricate,
especially with the emergence
of new challenges like post-quantum cryptography.
Starting now, collaboration
in anticipating future post-quantum implications is critical
for staying ahead of quantum processing
to ensure security in a post-quantum world.
As we go through this section,
we will cover many topics related
to advanced cryptographic concepts,
including cryptographic blockers, key management,
encryption techniques, security properties,
collaborative considerations, performance considerations,
post-quantum cryptography, and post-quantum implications.
First, we will look at cryptographic blocker.
Cryptographic blockers are obstacles or limitations
that hinder or delay the implementation
and effectiveness of encryption techniques.
Cryptographic blockers should be assessed
with a discussion of performance versus security.
Performance versus security refers to the trade-off
between the speed and efficiency of cryptographic processes
and the level of security they provide.
This means that higher security often requires
more complex algorithms,
which can slow down processing times, impacting performance.
For example, a highly secure encryption algorithm
like the Advanced Encryption Standard
or AES-256 offers strong protection
but may require more computational resources.
This use of resources leads to a slower performance compared
to a lighter, less secure encryption algorithm.
This trade-off is a critical consideration
when designing systems that need to balance robust security
with operational efficiency, especially in environments
where both speed and security are essential.
Next, we will explore key management.
Key management is made up of the processes
and protocols that generate, distribute, store,
and securely handle cryptographic keys
throughout their life cycle.
Key management concepts include key stretching
and key splitting.
Key stretching is a technique used to enhance the security
of weak or short cryptographic keys
by applying iterative hashing
or encryption functions to that key.
Key stretching makes brute force attacks more difficult.
Key splitting, on the other hand,
is a practice of dividing a cryptographic key
into multiple parts.
Each key part is then distributed
and stored separately to increase security.
Only by combining these separately stored key parts
can the original key be reconstructed.
In application, a system might use key stretching
to strengthen a user's password-derived key
before encrypting data,
and then employ key splitting to store portions
of the stretched key across different servers.
This practice would ensure
that even if one server is compromised,
the key remains protected.
After that, we will look at encryption techniques.
Encryption techniques encompass the methods
and algorithms used to convert plain text into ciphertext
to protect the data from unauthorized access.
Encryption techniques include
Authenticated Encryption with Associated Data or AEAD
and envelope encryption.
Authenticated Encryption with Associated Data
is an encryption technique
that simultaneously provides confidentiality, integrity,
and authenticity for both the encrypted message
and additional associated data.
The Authenticated Encryption with Associated Data ensures
that any unauthorized modifications
to the message or data are detectable.
Envelope encryption involves using a data key
to encrypt data
and then encrypting that data key with a master key.
This process ensures that both the data
and the data key are securely protected.
For example, in a secure messaging application,
the Authenticated Encryption with Associated Data
might be used to encrypt and authenticate a message
while envelope encryption securely manages the keys used
for encrypting the message,
ensuring that both the data and its encryption keys
are protected throughout the process.
Next, we will explore security properties.
Security properties are the essential attributes
of confidentiality, integrity,
and availability that ensure data protection.
Security properties are realized
through mutual authentication and forward secrecy.
Mutual authentication is a security process
where both parties
in a digital conversation verify each other's identity.
Mutual authentication ensures
that both ends of the connection are trusted
before data exchange occurs.
Forward secrecy, on the other hand,
is a property of cryptographic protocols
that ensures the security of past and future sessions
even if a private key is compromised.
This is done by generating unique session keys
for each session.
In this practice, a private key compromise
would only affect the current session.
The compromise would not affect past
or future session security,
assuming forward secrecy is maintained in the future.
In application, during a secure online transaction,
mutual authentication may be used to ensure both the client
and server authenticate with each other
before conducting the transaction.
Next, forward secrecy may be used to guarantee
that even if the server's private key is compromised,
past and future communication sessions remain secure.
Following that, we will look at collaborative consideration.
Collaborative considerations involve methods and protocols
that enable secure, cooperative computing and data sharing
among multiple parties without compromising security.
Collaborative considerations include techniques
such as homomorphic encryption
and secure multi-party computation.
Homomorphic encryption is a technique
that enables computations to be performed on encrypted data
without ever needing to decrypt it.
This allows sensitive data to be securely shared
with third parties for analysis
without risking its exposure or compromise.
With homomorphic encryption,
data remains encrypted throughout the sharing process,
ensuring that only the data owner
can decrypt and access the original information.
Secure multi-party computation, or SMPC,
is a cryptographic method
that allows several parties to work together
to compute a result using their own individual inputs
while keeping each party's input completely private.
This means that no one involved learns anything
about the other's data except the final shared secret.
In application, several companies may want
to collaboratively analyze each other's encrypted data sets
without exposing their own individual data to the group.
Homomorphic encryption would allow each company
to perform their analysis on encrypted data
while secure multi-party computation
would ensure that the results
are able to be computed collectively
without revealing individual underlying data sets,
maintaining privacy throughout the entire process.
Then, we will explore performance consideration.
Performance considerations balance the need
for strong security with the efficiency
and speed of cryptographic processes.
Hardware acceleration
is a primary performance consideration.
Hardware acceleration uses specialized hardware components
such as cryptographic processors or dedicated chips
to perform encryption and decryption operations faster
and more efficiently
than would be possible with software alone.
Hardware acceleration components are optimized
to handle specific cryptographic algorithms,
reducing the computational load
on general-purpose CPU processors.
In this way,
hardware acceleration improves overall system performance.
For example, on a high-frequency trading platform
where both speed and security are critical,
hardware acceleration may be employed
to execute complex cryptographic operations rapidly,
ensuring secure transactions
without compromising system performance.
Next, we'll explore post-quantum cryptography or PQC.
Post-quantum cryptography refers
to cryptographic algorithms specifically designed
to withstand the advanced threats posed
by quantum computers.
Quantum computers, with their immense computational power,
are expected to break many of the encryption methods
that are currently relied upon for security.
In this post-quantum cryptography section of the course,
we will compare post-quantum cryptography to Diffie-Hellman
and elliptic curve cryptography.
First, let's define quantum cryptography.
Quantum cryptography leverages principles like superposition
and entanglement to secure communication
at a level that is theoretically unbreakable.
Furthermore, any attempt to eavesdrop would be detectable.
Central to this capability is the use of Qubits,
which, unlike classical bits,
which can only exist as a one or a zero,
can exist in multiple states simultaneously.
This enables quantum computers
to perform many calculations at once,
dramatically increasing their processing power.
So, while quantum cryptography offers unmatched security,
it also drives the need for post-quantum cryptography
to protect against quantum computers
that could break current encryption methods.
Diffie-Hellman and elliptic curve cryptography
are vulnerable to quantum attacks,
specifically by quantum algorithms like Shor's algorithm.
Shor's algorithm could solve the mathematical problems
that Diffie-Hellman and elliptic curve cryptography rely on.
In summary, the realization of quantum computing
will necessitate a shift
to post-quantum cryptography algorithms that ensure
that encrypted data remains secure in a post-quantum world.
Finally, we will look at post-quantum implications.
Post-quantum implications involve the future challenges
and necessary adaptations
to secure data against the decryption capabilities
of quantum computers.
Post-quantum implications include assessing resistance
to quantum computing decryption attack
and emerging quantum implementations.
Resistance to quantum computing decryption attack refers
to the development of cryptographic algorithms
that can withstand the powerful decryption techniques
enabled by quantum computing.
Implementations of post-quantum algorithms
are being developed and tested
to replace or augment the current encryption methods
to ensure data remains secure
even as quantum technology advances.
For example, organizations are beginning to explore
and implement post-quantum algorithms
like lattice-based cryptography
to protect sensitive information.
This is being done because organizations anticipate a day
when quantum computers
could render current encryption models ineffective.
To finish things off, we'll take a short quiz
to see what you learn during this section of the course,
and we will review each of those quiz questions fully
to ensure you can explain why the right answers were right
and the wrong answers were wrong.
So let's get ready
to dive into advanced cryptographic concepts
in this section of the course.