Traffic measurement in IP networks

Summary form only given. Traffic measurement in the Internet, particularly traffic flow measurement, is an area of rapid growth in recent years, although the issue is not new at all. But many tools have been developed and methodology and technologies have been improved significantly. This tutorial gives an overview of methods, technologies and existing tools for traffic measurements. It starts with basic requirements, constraints, and problems of metering IP packets related to the Internet protocol and to common transport protocols. Then capturing I P packets at link layer level and at network level is discussed. For traffic metering, there exist several IETF standards and other de-facto standards. The tutorial gives an overview of these as well as of common low-level metering tools. On higher levels of IP traffic measurement, a large variety of tools, frameworks, and systems can be found supporting graphical display of measured flow data, integration and correlation of measurements from different locations, and integration with applications such as traffic engineering and accounting. For the tutorial, a representative subset of these was selected and is presented. Finally, an outlook is given including recent developments, current activities and challenges ahead.