A system for and method of analyzing packet traffic in a packet-switched network, including collecting traffic logs from a network operations center, wherein the traffic logs are representative of packet traffic passing through an actual configuration of the network, and wherein each traffic log includes the time the traffic log was created and an associated packet's network entry and exit points. The collected traffic logs are stored in a computer such that the traffic logs can be replayed. A computer file is thereafter created and is representative of a modified network configuration that is different from the actual configuration of the network. The traffic logs are replayed in coordination with the modified network configuration to generate a histogram file representative of packet traffic passing through or via at least one of a host, node or link in the modified network configuration.