Stream Ciphers: Trivium in Cryptography

Implementation 

Let us study the Hardware and Software Implementation of Trivium.

Hardware

Trivium in cryptography is a hardware-oriented design. It focuses on flexibility. It is compact in environments with restrictions on the gate count and power efficient on platforms with fewer power resources. It is usually fast in applications that require high-speed encryption. The design must also provide a way to parallelize its operations for power-efficient and fast implementations. We do not use a state bit for at least 64 iterations after it has been modified. In this way, We can compute up to 64 iterations at once. 3 AND gates and 11 XOR gates in the original scheme are repeated a corresponding number of times. This makes the clock frequency be divided by 64 without affecting the throughput.

Software

Even though Trivium in cryptography does not harm software applications, the cipher is efficient on a standard PC.

Security

Let us discuss the cryptographic properties of Trivium. The security requirement we use on Trivium in cryptography is that any type of cryptographic attack should not be significantly more straightforward to affect Trivium than any other stream cipher. This requirement is challenging to fulfill. 

Correlations

Two different correlations are essential when discussing the security of a synchronous stream cipher. The first type is correlations between linear combinations of keystream bits and internal state bits, potentially leading to a complete state recovery. The second type, exploited by distinguishing attacks, is correlations between the Keystream bits.

Algebraic attacks

Trivium is an easy target for algebraic attacks. We can explain the entire scheme with extremely sparse equations of low degrees. However, its state does not evolve linearly. The efficient techniques are implied to solve the systems of equations generated by LFSR-based schemes.

Resynchronization attacks

Another type of attack is a resynchronization attack, where the adversary can change the value of the IV and tries to extract information. Trivium tries to avoid this attack by cycling the state several times before producing any output.

Frequently Asked Questions 

What is the concept of Trivium?

Trivium is a hardware-oriented synchronous stream cipher. It was designed to explain the condition of a stream cipher without sacrificing its security, speed, or flexibility. 

Is Trivium an easy target for algebraic attacks?

Trivium is an easy target for algebraic attacks. We can explain the entire scheme with extremely sparse equations of low degrees. The efficient techniques are implied to solve the systems of equations generated by LFSR-based schemes.

How is the hardware of Trivium designed?

Trivium is a hardware-oriented design. It focuses on flexibility. It is compact in environments with restrictions on the gate count and power efficient on platforms with fewer power resources.

How does a resynchronization attack occur?

In a Resynchronization attack, the adversary can change the value of the IV and tries to extract information.

What are the two types of correlations in Trivium?

The first type is correlations between linear combinations of keystream bits and internal state bits, potentially leading to a complete state recovery. The second type, exploited by distinguishing attacks, is correlations between the Keystream bits.

Conclusion

This article has described the concept of Trivium in Cryptography. We hope that this blog gave you clarity on this topic. Eager to learn more about Cryptography? Refer to our other blogs on the same-

• What is Cryptography?
• Basic Cryptographic Tools.
• Cryptanalysis of Substitution Cipher.

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