how does cryptography enable the internet to process transactions securely? how does cryptography enable the internet to process transactions securely? polynumeric alphabets are used to encrypt and decrypt messages to allow for use with different languages. the public key encryption model is easy to use to encrypt data but intractable to decrypt for large numbers. frequency analysis is used to disguise the use of common letters in encrypted messages keeping passwords secure. symmetric keys are used to encrypt and decrypt messages for speed in processing to avoid being intercepted.