Study of number of packets in transit in a data network model near onset of congestion using functional fixed effect models

Performance of data communication networks is influenced by many factors, e.g. routing algorithms, traffic load, network connection topology. Using functional fixed effect models we study how the factors, routing cost metric, source load with various levels and their interactions affect a response metric, a network performance indicator “number of packets in transit”. Our focus is on the study near phase transition point (critical point) from free flow to congested states of a packet switching network model where throughput is the highest. We characterize the critical point by the level of packets production at sources. In our model we consider different dynamic routing cost metrics (i.e., when the costs of transmission of packets from one router to another incorporate the information about how congested the routers are) and static routing cost metric (i.e., when the cost of transmission of packets from one router to another is constant over time). Our work provides insight on the selection of the most efficient strategy to deliver packets to their destinations when the network is near congestion.