Methods and computer programs for generating data traffic matrices

A method of monitoring traffic flow within a network of nodes, and a recordable medium containing a computer program with instructions that, when executed, performs such method, is provided. The method comprises assigning sampling points to a node or unique pair of nodes. In one method, the sampling points contained within the assigned subset are determined to be the most likely to monitor data traffic, and preferably all data traffic, associated with the node or node pair. The sampling point subset may automatically be determined and assigned to the node or node pair, and such assignment can be based on historical traffic within the network. The method further comprises collecting diagnostic network traffic data from the sampling points, and obtaining sampled traffic flow counts for a flow associated with a node pair from the diagnostic traffic data collected from the sampling points assigned to the source and destination nodes of the node pair. The method further comprises performing a function, such as a combinatory function, on the sampled traffic flow counts to obtain an estimated traffic flow count for the respective flow. If multiple node pairs are monitored, a data traffic matrix containing a plurality of traffic flow counts can be generated.