Policy-based QoS Management
For years the Internet networking community has been struggling to develop ways to manage networks. Initial attempts brought mechanisms and protocols that focused on managing and configuring individual networking devices i.e. the Simple Network Management Protocol (SNMP). This model worked well in early deployments of IP management systems for local and metropolitan area networks but now, with the evolution of Quality of Service (QoS) models such as the Differentiated Services framework, the complexity and overhead of operating and administrating networks increases enormously. There is also a need to be able to program management systems and network components to adapt to emerging requirements and subsequently be able to dynamically change the behaviour of the whole system to support modified or additional functionality. The emerging Policy-based Network Management paradigm claims to be a solution to these requirements. Policy-based Management can guide the behaviour of a network or distributed system through high-level declarative directives that are dynamically introduced, checked for consistency, refined and evaluated, resulting typically in a series of low level actions.
This section of the Quality of Service Management Information Portal serves as a focal point for research related to Policy-based Network Management.
The task of managing information technology resources becomes increasingly complex as managers must take heterogeneous systems, different networking technologies, and distributed applications into consideration. As the number of resources to be managed grows, the task of managing these devices and applications depends on numerous system and vendor specific issues. Policy Based Network Management (PBNM) provides a means by which the administration process can be simplified and largely automated.
A policy, the basic building block of a policy-based system, is a set of rules that govern the choices in behaviour of a system. For a network-specific policy these rules define which traffic should be treated differently in the network, and how so. A policy can be represented at different levels, ranging from business goals to device-specific configuration parameters. Policies belonging to the two extreme levels of abstraction are referred to as high and low-level respectively.
Policies are seen as a way to guide the behaviour of a network or distributed system through high-level, declarative directives. The Internet Engineering Task Force (IETF) has been investigating policies as a means for managing IP-based multi-service networks, focusing more on the specification of protocols and the object-oriented information models for representing policies. The declarative high-level aspect of policies is very important, particularly for human managers since it addresses the current problem of managing heterogeneous network devices in a one-by-one fashion, providing improved scalability. The second important benefit of policies is the ability of adapting the management system to changing or newly emerging requirements without having to interrupt its operation or recode part of its hardwired functionality. The aforementioned salient characteristics of policy-based management constitute the basic reasons for being widely adopted by organisations such as the IETF and Distributed Management Task Force (DMTF) as well as by many equipment vendors, e.g. CISCO, as the new promising management solution.
Policy-based management has been considered by two working groups in the IETF. The first one, Resource Allocation Protocol Working Group (WG), has described a framework for policy-based admission control specifying the two main architectural elements:
The list of journals, conferences and technical societies related to multicast communication does not mean to be exhaustive rather it is indicative. For additions/updates please contact the webmaster.