Symmetric cryptography encrypts data in blocks of sixty-four bits, due to computer technology of the time of implementation. The key to encrypt and decrypt the data is a stream of ones and zeros, of varying size from sixty-four to four hundred and forty-eight bits. The same key is used to encrypt and decrypt the data. Symmetric cryptography is faster to decrypt and encrypt and the key is shared between both users, providing confidentiality and access controls. Symmetric being faster to compute makes it less secure. Symmetric is better to encrypt larger amounts of data.
Asymmetric cryptography encrypts data using two keys, one public key for encrypting and the private key for decrypting. Key sizes can be much larger the symmetric and takes significantly more time to encrypt and decrypt, so it is best used for small amount of data due to time. The key exchange is more secure as it is handled by the PKI, a third-party system to maintain integrity. Asymmetric encryption offers better security and tamper proof.