Characteristics of origin-destination pair traffic in Funet

Abstract

In this paper we analyze measurements gathered from a 2.5 Gbps link in the Finnish university network (Funet)

Blind maximum likelihood estimation of traffic matrices under long-range dependent traffic

“…The main conclusion is that stationarity can be reasonably assumed to hold within periods of 30-90 min. The empirical studies performed in [15,11,16] for Funet data essentially confirm the stationarity assumption in [7] (again, a time aggregation from 1 s to 300 s is used).…”

“…This point is also raised in [28]. Empirical analyses supporting the homogeneity assumption are in [11,26].…”

“…The autocorrelation of the cumulative aggregate (bits/packet) arrival process at the level of OD pair has been recently analyzed at a time scale either relevant for traffic matrix estimation or suitable to detect long memory (time aggregation varying from 1 s to 300 s). In particular, the presence of long-range dependence of traffic data is shown in [15,11] through the analysis of the correlation between the standardized residuals of the bits (packets) arrival process (bit/packet network traffic) at lag k of an OD pair at various time aggregation levels; in [26], again with a time aggregation for 10 ms to 60 s, through wavelet analysis (as developed in [27]); and in [14] through a visual analysis. All the above mentioned papers show that OD traffic is characterized by the presence of long-range dependence (with values of the Hurst parameter H ranging between 0.65 and 0.9 for aggregation time 1-300 s).…”

“…The assumption of independence between OD pairs has been studied for real data in [11], via the correlation between the standardized residuals of the bits (packets) arrival process (bit/packet network traffic) of two different OD pairs at various time aggregation levels. The data at hand are measurements observed on one link in the Finnish university network (Funet), and partitioned into OD traffic on the basis of source and destination IP addresses; time aggregation varies from 1 s to 300 s. The main conclusion is that there is no particular evidence against the assumption of independence among OD pairs.…”

“…Such an assumption has been considered in [7,14,15,11,16], and validated via QQ-plots and related correlation tests comparing the empirical distribution with a fitted Gaussian distribution. The data at hand are obtained from the traffic observed on one link, which is partitioned into OD traffic based on source and destination IP addresses (time aggregation from 1 s to 300 s), except in [7] where the data are the traffic observed on the links and OD pairs of a onerouter network with 5 min time aggregation, as provided by SNMP.…”