Cross domain and cross layer coarse grained quality of service support in IP-based networks

deshalb auf die primitive Verkehrstrennung in mehrere Klassen, die in den Weiterlei-tungsknoten getrennt abgelegt und mit verschiedenem Vorrang behandelt werden. Abstract The increasingly popular Internet with a steadily growing user base, the resulting traffic load and its rising usage for time and loss critical services, such as voice over IP, video streaming and gaming, consists of about 30,000 interconnected service provider networks. Those interconnections are based on the Internet Protocol (IP) and do not distinguish the mixed traffic types within the transported traffic load. The currently observed and mostly sufficient service quality can only be achieved by network internal and inter-domain link capacity over-provisioning. Resource utilization of about 10% is commonly applied to achieve stable and un-congested network operation. However, service providers are increasingly deploying Quality of Service (QoS) support mechanisms within their network domain in order to provide traffic separation and differentiated forwarding. Not only IP QoS, but also underlying link layer QoS mechanisms are applied. Such QoS support is currently removed at the interconnection link and possibly reapplied in an independent and uncoordinated fashion in the neighbouring domain. A new cross-domain and cross-layer coarse grained Quality of Service support concept has therefore been drafted, which allows for the automated inter-domain class of service (CoS) support information exchange about the distinguished traffic classes at different networking layers. The concept is based on the standard inter-domain signalling protocol, the Border Gateway Protocol (BGP) version 4. Transitive BGP-based cross-domain signalling and cross-layer CoS mapping is a novel contribution. The cross-domain signalling of cross-layer mapped class set information has been submitted for standardization within the Internet Engineering Task Force (IETF). This includes a class overload prevention signalling by means of applied token bucket based ingress limitations. Global scale usage and omnipresent traffic class of service support is targeted with the proposed and implemented concept. It is likely, that service providers might be tempted to misuse offered service classes, hence the overload limitation. Three major contributions are documented within this thesis: 1. A comprehensive compilation of QoS support concepts with detailed network and node internal building block descriptions has been arranged, which proves the technical readiness of currently deployed devices for an inter-domain CoS based interconnection. 2. The drafted specification of the new inter-domain CoS concept including the CoS marking and class overload limitation signalling is detailed herein. 3. Simulations and implementations of vital building blocks of the concept have been made to …