## About TIGER160,3 hash

Tiger160,3 is a cryptographic hash function that belongs to the Tiger hash family, specifically producing a fixed-length hash value of 160 bits (20 bytes). The "3" in the name refers to the number of rounds used in the compression function of the Tiger hash.

### Characteristics of Tiger160,3

**Fixed-Length Output**:- Tiger160,3 produces a fixed-length output of 160 bits (20 bytes).

**Input Padding**:- Tiger160,3 pads the input message so that its length is congruent to 512 bits (64 bytes) modulo 256. It appends a single '1' bit followed by '0' bits until the message length is 256 bits less than a multiple of 512. The length of the original message is then appended in bits.

**Processing in Blocks**:- Tiger160,3 processes the input message in 512-bit (64-byte) blocks.

**Initialization Vector (IV)**:- Tiger160,3 uses an initial vector (IV) that is initialized during the setup of the compression function.

**Compression Function**:- The compression function of Tiger160,3 operates on a 512-bit state and uses a combination of substitution-permutation network (SPN) and a Feistel-like structure. It involves three rounds of mixing, substitution, and permutation operations.

### Algorithm Steps

**Initialization**:- Initialize the 512-bit state and set the initial vector (IV).

**Padding**:- Pad the input message according to the specified padding rules.

**Processing**:- Divide the padded message into 512-bit blocks.
- For each block, apply the three rounds of the compression function, updating the state.

**Output**:- After processing all blocks, extract the final 160-bit hash value from the state to produce the hash value.

### Security and Usage

**Security**:- Tiger160,3 is designed to provide moderate security against collision attacks and preimage attacks. Its 160-bit output size offers better security properties compared to shorter variants like Tiger128,3.

**Usage**:- Tiger160,3 has been used in various applications requiring a 160-bit hash function, such as checksums and data integrity verification. However, its adoption has been somewhat limited compared to more widely accepted hash functions like SHA-2 and SHA-3, which offer stronger security assurances and are more standardized in modern cryptographic protocols.

### Summary

Tiger160,3 is a cryptographic hash function that produces a 160-bit hash value. It provides moderate security properties against certain types of attacks and has been used in specific applications where a 160-bit hash function is sufficient. However, its usage has been overshadowed by more widely recognized hash functions with stronger security guarantees in contemporary cryptographic applications.