Communication method, transmitter node, authenticator node, and receiver node

[0001] A communication method is disclosed which provides multicast source authentication. The method is carried out by a transmitter node, an authenticator node, and multiple receiver nodes. The method protects a payload transmitted in a multicast frame to multiple receivers. The transmitter computes a source authentication tag and an integrity-protecting tag based two Message Authentication Code (MAC) schemes. The method further computes an aggregated tag based on an aggregation of the source authentication tag and the integrity-protecting tag; and determines a multicast frame based on the payload and the aggregated tag. The authenticator node modifies the multicast frame during transmission by (1) recomputing the source authentication tag, and (2) aggregating the recomputed source authentication tag with the multicast frame. Receivers can only correctly verify the multicast frame if the transmitter node correctly computed the source authentication tag and the integrity-protecting tag and if the authenticator node correctly modified the frame.