Inline measurements: a native measurement technique for IPv6 networks

Next generation convergence networks require ubiquitous measurement mechanisms able to assess dynamically the performance quality characteristics experienced by the different, aggregated traffic flows traversing end-to-end Internet paths. Existing service measurements fall into two main categories: active and passive. The paper introduces a complementary technique called 'inline measurements' that makes use of the extendible features of the emerging IPv6. Through the exploitation of native IPv6 extension headers, measurement triggers and minimal measurement data may be carried in the same packets as the payload data itself, providing a high level of probability that the behaviour of the real user traffic flow is being observed. By adding measurement functionality natively, at the network (IPv6) layer, inline measurements can potentially target all transport and application services, providing an accurate performance evaluation framework for next generation networks. The paper also presents the results from a dynamically configurable prototype implementation in which end-to-end, one-way delay and delay variation of real-time video streams have been measured.