Patent ID: 8072985

Claim:
A method for a server to calculate access router to access router traffic matrixes by using ingress and egress files derived from flow records, each ingress file comprising a plurality of ingress records in which each ingress record represents an incoming flow, each egress file comprising a plurality of egress records in which each egress record represents an outgoing flow, comprising: identifying ingress records in the ingress files and egress records in the egress files that match; and calculating a traffic matrix using the ingress records and egress records that are matched, wherein the calculating the traffic matrix comprises creating a hash set for each egress file, and wherein the identifying and the calculating are performed by the server, wherein the calculating the traffic matrix further comprises: creating a key value by concatenating source addresses and destination addresses from an egress record; adding the key value to the hash set; and creating a second key value by concatenating source addresses and destination addresses from an ingress record.