MACSec implementation

A media access control (MAC) security apparatus for a local area network interface includes a parser, an encryption engine, an authentication engine, and a first buffer. The parser is configured to output packets. The encryption engine is configured to receive the packets from the parser and generate encrypted data based on the packets received from the parser and cryptographic primitives. The encryption engine includes an advanced encryption standard engine configured to form the cryptographic primitives. The authentication engine is configured to perform authentication operations of the local area network interface based on the encrypted data from the encryption engine. The first buffer is configured to interface the encryption engine to the parser. The parser and the encryption engine process data at different rates. The first buffer is configured to compensate for the different rates.