fnss.traffic.trafficmatrices.stationary_traffic_matrix

stationary_traffic_matrix(topology, mean, stddev, gamma, log_psi, n, max_u=0.9, origin_nodes=None, destination_nodes=None)

Return a stationary sequence of traffic matrices.

The sequence is generated by first generating a single matrix assigning traffic volumes drawn from a lognormal distribution and assigned to specific origin-destination pairs using the Ranking Metrics Heuristic method proposed by Nucci et al. [2]. Then, all matrices of the sequence are generated by adding zero-mean normal fluctuation in the traffic volumes. This process was originally proposed by [2]

Stationary sequences of traffic matrices are generally suitable for modeling network traffic over short periods (up to 1.5 hours). Over longer periods, real traffic exhibits diurnal patterns and they are better modelled by cyclostationary sequences

Parameters:

topology : topology

The topology for which the traffic matrix is calculated. This topology can either be directed or undirected. If it is undirected, this function assumes that all links are full-duplex.

mean : float

The mean volume of traffic among all origin-destination pairs

stddev : float

The standard deviation of volumes among all origin-destination pairs.

gamma : float

Parameter expressing relation between mean and standard deviation of traffic volumes of a specific flow over the time

log_psi : float

Parameter expressing relation between mean and standard deviation of traffic volumes of a specific flow over the time

n : int

Number of matrices in the sequence

max_u : float, optional

Represent the max link utilization. If specified, traffic volumes are scaled so that the most utilized link of the network has an utilization equal to max_u. If None, volumes are not scaled, but in this case links may end up with an utilization factor greater than 1.0

origin_nodes : list, optional

A list of all nodes which can be traffic sources. If not specified all nodes of the topology are traffic sources

destination_nodes : list, optional

A list of all nodes which can be traffic destinations. If not specified all nodes of the topology are traffic destinations

Returns:

tms : TrafficMatrixSequence

References

[2]	(1, 2, 3) Nucci et al., The problem of synthetically generating IP traffic matrices: initial recommendations, ACM SIGCOMM Computer Communication Review, 35(3), 2005