Ready your fingers for Fingerprinting

Characteristics 

The fingerprints are unique, even for twins. The three characteristics of fingerprints are - 

• Loops - This is the most command characteristic. In fingerprinting, lines go out and point back toward itself. 

Source - Research Gate

There exist two types of loops:

1. Radial Loops - the loops that point toward the thumb. 
2. Ulnar Loops - the loops that point toward the pinky. 

• Whorls - The circular raised lines are known as whorls. 

Source - Research Gate

These whorls exist in four different patterns:

1. Plain - The circle within circles. 
2. Pocket loop - The pattern starts as a loop and ends as a whorl.
3. Double loop - In this, two loops are in opposite directions. 
4. Accidental loops - It is the second most common fingerprint characteristic. It is like an irregularly shaped whorl. 

• Arch - The lines that look similar to a mountain. These lines start low from one end, rise in the middle, and go back down. 

Source - Research Gate

These arches exist in two types:

1. Plain - The arch in which raised line enter from one side. These lines then make a rise in the center. In the end, flow out on the opposite side. The whole pattern is made of one single line.
2. Tented - Unlike plain arch, tented arch consists of two independent lines. These two lines make an angle when they come together. 

Properties

The main two properties of fingerprinting in cryptography are-

• Virtual Uniqueness

The amount of data to protect is vast, and the difference is almost negligible. The fingerprinting algorithms should be designed to reduce the probability of collision. So for large systems, fingerprinting requires strong virtual uniqueness. So, an excellent fingerprinting algorithm must ensure that distinct fingerprints are generated. 

• Compounding 

Computer systems combine the files in different ways, like concatenation, symbolic addition, etc,. So fingerprinting algorithms allow computing of the fingerprint of a file from the fingerprints of its constituent parts. The property of a fingerprinting algorithm is known as compound property. 

Algorithms

We need to follow good fingerprinting algorithms to generate fingerprints. These algorithms include - 

• Rabin’s Algorithm

Michael O. Rabin proposed this algorithm. It is the easiest and fastest way to create fingerprints. Fingerprints created use mathematical analysis to calculate the collision probability. This approach also uses polynomials for implementing fingerprints. 
 

• Hash Functions

The cryptography hash function is a mathematical algorithm. It maps arbitrary-sized data into a fixed-size bit array. It is widely used in modern cryptography as an essential tool. These hash functions are deterministic and have the following properties - 

1. Computation is high-speed.
2. The level of difficulty is very high. 
3. Uniqueness in hash values - with a slight change in message, the value of the hash function also changes. 
4. The hash function algorithm generates strongly collision-resistant fingerprints. 
5. The fingerprints generated are almost beyond the reach of the malicious adversary. 

Uses of Fingerprinting

Fingerprinting enables unique identification. Thye considers numerous minor details. They are used for the majority of purposes. Some of them are -

• Banking: Customers want their identity to be secured. So, the use of fingerprinting in banks delivers a seamless experience. 
   
• Home Assistants: Fingerprint locks protect our houses from robberies. Other than fingerprinting, face locks and voice assistants are also used for security purposes. 
   
• Airports: Travelers taking international flights have to submit fingerprints. These are used for verification and security purposes. 
   
• Authentication: It is the most common use of fingerprinting. Apple first introduced fingerprint recognition in mobile phones. Since then, the fingerprint has evolved in mobile security. 
   
• Making a Match: Fingerprints can help identify the criminal. Fingermarks found can be cross-checked. 

Public Key Fingerprints

A public key fingerprint is a short sequence of encoded data into bytes. These fingerprints are created using hash function algorithms. These fingerprints are used in key management as they are shorter than the actual key used. Examples of public key fingerprinting include - SSH, Groove, peer-to-peer networks, etc. 

As the name suggests, these keys are open to the system environment. Therefore, the primary responsibility of fingerprinting in cryptography is the security of public keys. Security can be increased by increasing the cost of calculating fingerprints. Moreover, there must exist collision-resistant functionality.  

Frequently Asked Questions

What is cryptography?

Cryptography is a method of encrypting and decrypting messages and information to establish a secure information exchange between the sender and the receiver.

What does fingerprint mean?

A fingerprint is a short key that is used to identify long keys. These are used for authentication, authorization, etc. 

What are the properties of fingerprinting?

Fingerprinting consists of two main properties. These are - compounding and virtual uniqueness. 

What is public key fingerprinting?

In cryptography, fingerprints encoded in a short sequence of bytes are called public key fingerprints. 

What algorithms can be used to create fingerprints?

The algorithms used for generating fingerprints are- Rabin’s algorithm and the Hash function. 

Conclusion

In this article, we have discussed the cryptography fingerprinting technique. Starting with an introduction to fingerprinting. We discussed some of the properties of fingerprinting and studied some algorithms used for it. In the end, we discussed public key fingerprinting. 

We hope this blog increased your knowledge of fingerprinting and that you all enjoyed reading it. Do upvote our blogs if you find them engaging and knowledgeable. 

For more on cryptography, check out our other blogs

1. Cryptosystems
2. Difference between Cryptography and Cyber Security
3. Cryptography Hash Function
4. Monte Carlo Simulation
    

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