IP/MPLS network performance and QoS. Part 1: Performance metrics efinitions and practical usage

The paper focuses on network performance management through active measurement. It looks at the reference path and terminology used. IP parameters and metrics are summarised and compared. Metric development in-progress is discussed. There are new challenges in performance measurement for MPLS-enabled IP networks because of new network protocols and a new class of failures. Detection of this new class of failures requires active measurement implementations such as ping for connectivity and dedicated measurement systems. Practical implementations are considered from the point of view of service providers, customers, and third parties. The paper gives the IP measurement design with which AT&T continuously measures its IP network as part of QoS assurance.