Abstract: Concerning the high performance, QoS supported transport services, it is not sufficient that only the traffic transport under a single domain or Autonomous System (AS) is under the consideration. Inter-domain QoS routing is also in a great need. In this proposed work we identify the challenges that need to be addressed in designing a three level core which consists of policy making, packet queuing and forwarding and resource utilization itself concerning the good performance, QoS supported convey services, it is not adequate that only the traffic transport under a single domain or Autonomous System (AS) is under the thinking. Inter-domain QoS routing is also in a great need. As there has been empirically and hypothetically proved, the dominating Border Gateway Protocol (BGP) cannot address all the issues that in inter-domain QoS routing. Thus some protocol or system architecture has to be developed to be able to carry the inter-domain traffic with the QoS and TE consideration. Moreover, the current network control also lacks the ability to cooperate between different domains and operators. The appearance of label switching transport technology such as of Multi-Protocol Label Switching (MPLS) or Generalized MPLS (GMPLS) supports the traffic transport in a finer granularity and more dedicated end-to-end Quality of Service classes.
Keywords: Gateway, Router, QoS, NGN, MPLS.