Experimental Validation of SLAs in Operational Networks through Hash-based Packet Sampling

In operational networks, services are delivered according to specific Service Level Agreements (SLAs). To ensure the SLAs stipulated with the users, providers make use of traffic monitoring and measurement tools controlling their highspeed IP networks. In order to improve the scalability of the measurement systems, techniques which allow to reduce the total amount of data to be collected and processed are currently being standardized in the IETF Packet Sampling (PSAMP) Working Group. Among packet sampling techniques, hash-based one is the only capable of providing a feasible framework to monitor One-Way Delays (OWDs). This paper is focused on the experimental validation of SLAs conformance in operational networks using hash-based packet sampling techniques. The results presented hereafter are obtained from the analysis of traffic traces collected at two different points of operational networks. Such results are fundamental to validate the whole hash-based packet sampling framework, because they complement the already available results on the uniformity of distribution, computation speed and statistical properties of the hash functions calculated by using single point traces.