MAC aggregation with message multiplicity for use in a multi-node data network

A MAC aggregation technique utilizing a large field addition operation is disclosed. The large field addition operation defines the addition of two or more MACs mod p, where the two or MACs may comprise constituent MACs or aggregate MACs, and where p is a prime number that is large relative to the size of the MACs. The disclosed MAC aggregation technique yields an aggregate MAC much shorter than the concatenation of constituent MACs while achieving security even in the case where constituent MACs may be aggregated in duplicate.