A user-based approach for the choice of the IP services in the multi domains DiffServ Internet

This paper deals with the design of a distributed architecture and of mechanisms that are able to guarantee quality of service (QoS) in a set of DiffServ domains. The design includes the proposal of a signaling protocol to accept or reject the transmission of flows in a set of adequately controlled domains. More particularly, it provides a proposal for (1) selecting the end-to-end QoS paths resulting from concatenations of the IP services provided by the domains involved in the data path and (2) ensuring that the chosen concatenations fulfil the requested user QoS requirements. With respect to other work, this paper first tries to minimise the use of network resources by discovering the real performance of each domain. Second, the signaling protocol is designed to bring as less constraints as possible on the architecture. It defines the end-to-end concatenations only as a set of transfer bridges, or inter-domain links, and leaves all internal domain paths fully open to any implementation by the domain providers. The architecture, based on the use of bandwidth brokers, provides an answer to the two main problems related to such approaches, i.e. how to identify and build the sequence of the needed bandwidth brokers and how to select the ingress and egress routers of each of these domains to construct the end-to-end paths.