What does differential analysis focus on in the context of cryptanalysis?

Differential analysis in cryptanalysis specifically examines the differences between pairs of plaintexts and their corresponding ciphertexts after being processed by a cryptographic algorithm. The key concept is to look for patterns that emerge based on how slight changes in the input data (the plaintext) correlate with changes in the output data (the ciphertext). This can reveal weaknesses in the encryption scheme and help cryptanalysts to uncover potential vulnerabilities, ultimately aiming to recover the encryption key or discern information about how the encryption process operates.

This method is particularly effective against symmetric key algorithms and can provide insights into the structure and design of the encryption algorithm being analyzed. By analyzing how changes to certain bits in plaintext affect the ciphertext, cryptanalysts can devise techniques that exploit these predictable relationships, leading to effective attacks on the cryptographic system.