managed by Paulo Gonçalves

/!\ THIS IS A WORK IN A PROGRESS /!\

Overview & Goals

Metrology of Wide Area Networks  – i.e., the deployment of a series of tools allowing the collecting of relevant information regarding the system's status – is a discipline recently introduced in the context of networks, that undergoes constant developments. In a nutshell, this activity consists in measuring along time, the nature and amount of exchanged information between the constituents of a system. It is then a matter of using the collected data to forecast the evolution of the network's load, so as to anticipate congestion, and more widely, to guarantee a certain Quality of Service, optimizing resource usage and protocol design.

From a statistical signal-processing viewpoint, collected traces correspond to (multivariate) time series principally characterized by non-properties: non-gaussianity, non-stationarity, non-linearities, absence of a characteristic time scale (scale invariance). Our research activity is undertaking the development of reliable signal-analysis tools aimed at identifying these (non-)properties in the specific context of computer network traffic. Doing this, we intend to clarify the importance of granularity of measurements.

Another challenge in network metrology is the effectiveness of packet sub-sampling. It means collecting only a fraction of the overall traffic (supposedly redundant) and studying the possibility of inferring from that partial measurement the most complete information about the system. Non-trivial questions – such as which fraction, which sub-sampling rule, adaptativity of this latter, smart sampling, statistical inference – open up a broad scope of investigation.

Projects & Partners

Results & Software

• Design and development of a fine-grained traffic-capture and traffic-analysis system dedicated to 10Gb/s speed links
• Comparison of sampling methods for characterizing heavy-tailed distributions in high-speed networks traffic