This document describes the design and implementation of a Message Authentication Code (MAC) with integrated error correction capability called MAEC. MAEC uses a cellular automata (CA) based error correcting code to provide resilience against random errors during transmission. The key steps are: (1) Data is padded and partitioned into blocks, (2) A random maximal-length CA rule is selected based on a key using Rabin's irreducibility test, (3) Checkbytes are computed by encoding the data blocks using the CA, (4) The checkbytes and a key are mixed using NMix to generate the MAC tag, (5) During verification, received checkbytes are compared to recomputed checkbytes using the CA to detect