a method and apparatus are described for supporting the full mesi protocol in a distributed shared memory environment implementing a snoop based architecture . a requesting node submits a single read request to a snoop based architecture controller switch . the switch recognizes that a responding node other than the requesting node and the home node for the desired data has a copy of the data in an ambiguous state . the switch resolves this ambiguous state by snooping the remote node . after resolving the ambiguous state , the read request transaction is completed .