1. A computer system comprising a plurality of processors and a plurality of memories, the plurality of memories providing for storage of host memory data divided into blocks of host memory data, the processors and the memories being distributed among a plurality of different nodes, the different nodes being connected by an interconnection network; the host memory data being referenced by a host memory address used for locating the blocks of host memory data stored in a host location in one or more of the different nodes using a memory consistency protocol, the memory consistency protocol utilizing an exchange of memory consistency control packets sent between at least two individual nodes included within the plurality of different nodes; each individual node comprising: A) a multiprocessor group including a number of the processors; B) a cache memory for containing cached blocks of host memory data; C) a number of memories of this individual node which are included in the plurality of memories of the computer system; D) a memory controller connected for controlling the number of memories of this individual node, the memory controller including a memory controller directory which contains information relating to the memory consistency protocol for the blocks of host memory data stored in any of the memories of this individual node and in any cache memory of this individual node; E) a node controller, the node controller connected to the multiprocessor group and to the memory controller, the node controller including an imported directory for tracking any block of host memory data imported to any cache memory of this individual node; F) the memory controller directory further providing storage of a presence vector for each block of host memory data stored in this individual node, each presence vector providing information referencing at least one host location for the memory address within at least one of the plurality of different nodes, the host location designating a local node when it references host memory data within the same node as the memory controller, and the host location designating a remote node when it references host memory data outside that same node; G) means for parameterizing all host locations possible in each presence vector; and, H) means for enabling that the packets exchanged between the different nodes within the computer system include an item of destination information derived from the presence vector referencing the host location for implementing the memory consistency protocol so as to eliminate need in the node controller for an export directory for the tracking of blocks of host memory data exported from this individual node to any remote node.