Tiny Encryption Algorithm (TEA)
Tiny Encryption Algorithm (TEA) is a simple block cipher that uses a 64-bit block length and a 128-bit key.
- algorithm assumes a computing architecture with 32-bit words
- all operations are implicitly modulo
- means any bits beyond the 32nd position are automatically truncated
- all operations are implicitly modulo
- number of rounds is variable, but must be large
- conventionally, 32 is considered secure
- each round of TEA is comparable to 2 rounds of a Feistel cipher
- roughly equal to 64 rounds of DES
- for block ciphers, there is a trade-off between the complexity of each round and the number of rounds required
- some use less rounds of greater complexity
- TEA uses many simple round functions
- an obscure key-related attack exists
- low-probability and can usually be safely ignored