Interdomain QoS Paths Finding Based on Overlay Topology and QoS Negotiation Approach [chapter]

Serban Georgica, Eugen Borcoci
2010 Trends in Telecommunications Technologies  
Introduction The real time multimedia services, delivered on Internet networks, raised new challenges for the network regarding the end to end (E2E) quality of services (QoS) control in order to ensure the proper delivery of the services from content provider (source) to content consumer (destination). But, despite a lot of studies and research done, the actual traffic processing in real Internet deployments is still mostly best effort. Several approaches have been proposed, focused on
more » ... ing aspects -usually solved in the management planeand then performing monitoring and adjustments in the control plane: e.g., well known dynamic techniques have been standardized, like IntServ, Diffserv, or combinations. Offering multimedia services in multi-domain heterogeneous environments is an additional challenge at network/ transport level. Service management is important here for provisioning, offering, handling, and fulfilling variety of services. Appropriate means are needed to enable a large number of providers in order to extend their QoS offerings over multiple domains. To this aim, an integrated management system can be a solution to preserve each domain independency while offering integration at a higher (overlay) layer in order to achieve E2E controllable behaviour. This chapter deals with the problem of establishing QoS enabled aggregated multi-domain paths, to be later used for many individual streams. A general framework is described exposing the ideas of overlay topologies solutions. Then a simple but extendable procedure is proposed, running at management level, to find (through communication between domain managers) several potential inter-domain end to end paths. Then, using a resource negotiation process performed also in the management plane, QoS enabled aggregated pipes, spanning several IP domains, are established. All these functions are performed at an overlay level, based on abstract characterization of intra and inter-domain capabilities delivered by an intra-domain resource manager. This is important in the sense that each domain (or, Autonomous System -AS) can preserve its own independency in terms of resource management. The subsystem is part of an integrated management multi-domain system, dedicated to end to end distribution of multimedia streams. The QoS path finding solution presented here is not like a traditional routing process: it is not implemented on routers, and it does not choose a route between network devices, but between two or more nodes of an overlay virtual topology described at inter-domain level. 16 www.intechopen.com Trends in Telecommunications Technologies 346 Together with the intra-domain QoS routing available inside each network domain we will obtain an E2E QoS routing solution. We recall that in our context, QoS enabled aggregated pipes are established (at request of a Service Provider entity), in advanced to the real traffic flow transportation. These are midlong term virtual links. Related to this, the main advantage of the proposed solution is that, by separating the process of path finding from the QoS negotiation, the path searching process doesn't need to work real time. So, one can find several paths in very complex overlay topologies. Also, the overlay topology is made simple by virtualisation: each domain (including its manager) is considered as an abstract node in the virtual topology. Therefore the solution is scalable and capable to work in cases of large topologies, being no need for a hierarchical approach. This Chapter is organized as follows: the Section 2 contains the state of the art in QoS interdomain routing; the Section 3 shortly describes the general Enthrone architecture focusing on the service management at the network level. The Section 4 introduces the proposed QoS inter-domain path finding solution. Section 5 presents details about the implementation and Section 6 contains conclusions, possibilities of extensions and open issues.
doi:10.5772/8497 fatcat:unlyfahxszfbzc3c3bbs6qmb7q