Simplify the following text for a Grade 12 native English-speaking person.
Original: During encryption , a block cipher algorithm might take ( for example ) a 128-bit block of plaintext as input , and output a corresponding 128-bit block of ciphertext .
Simplified: A block cipher encryption algorithm might take ( for example ) a 128-bit block of plaintext as input , and output a corresponding 128-bit block of ciphertext .