A Mobile IP allows IP hosts to move between different networks without changing their IP addresses. Mobile IP systems supporting local registration were introduced to reduce the number of times a home registration with the remotely located home agent was needed. The local registration Mobile IP scheme enhanced performance by processing registration requests of mobile nodes at a local agent. The local registration approach may affect other aspects of the Mobile IP systems such as fault tolerance. In this paper, we briefly review previous solutions for supporting fault tolerance in local registration Mobile IP systems and propose a fault tolerance protocol with a backup foreign agent in a hierarchical local registration mobile IP to enhance the efficiency of such systems against foreign agent failures. We also describe the specification of the proposed protocol using LOTOS and perform its validation using MiniLite. Finally, we analyze the performance of our proposed fault tolerance protocol through simulation.

-To reduce frequent changes and upgrades of management systems, we need a guideline of OSS's architecture and development methods of the OSSs. TMF has proposed NGOSS technology-neutral architecture (TNA) which describes major concepts and architectural details of the NGOSS architecture in a technologically neutral manner. The NGOSS TNA can be mapped onto appropriate technology-specific architectures (TSAs) using specific technologies such as XML, Java and CORBA. Web services, which is a distributed and services-oriented computing technology, can be applied to NGOSS TSA. In this paper, we examine the architectural requirements of TNA, and provide a design of Web servicesbased TSA in accordance with the TNA requirements.

Abstract.To avoid frequent changes of OSS's architecture, TNA provides NGOSS architecture in technology-neutral manner. TNA can be mapped to appropriate TSAs using specific technologies such as XML, Java and CORBA. Web Service can be applied for NGOSS TSA. In this paper, we examine architectural principles of TNA and propose an application mechanism of Web services technologies to TNA.

It was impossible to find a globally optimal route on hierarchical transport network because of the successive subnetwork partitioning and network topology abstraction. So, this paper proposes a hierarchical routing model that provides a globally optimal route on hierarchical ATM transport network. In addition, this paper proposes distributed connection management architecture adopting the proposed routing model. The hierarchical routing model and the distributed connection management architecture are specified in terms of information, computational and engineering viewpoints of RM-ODP. We implement the proposed routing model and the distributed connection management architecture, and show that the proposed connection management architecture always provides a globally optimal route with admissible performance by empirical performance analysis.

To meet the upcoming demands of reliable delivery of QoS guaranteed multimedia IP traffic over a large-scale ATM network, this paper proposes two algorithms. One is a Bounded Flooding Routing Algorithm (BFRA) that provides a globally optimal VPC to deploy IP network over a G.805-based hierarchical ATM VP transport network, which was impossible because of a successive network topology abstraction or aggregation. The other is the ATM VPC reconfiguration algorithm (AVRA) to cope with IP network performance degradation that is mainly caused by increase of traffic load or transit delay of the IP network and the ATM VPC abnormality of ATM VP network. This paper describes an implementation model of ATM VP Network Management System (ATM VP-NMS) to maximize the performance of VPC provisioning and reconfiguration and to ensure the unceasing VPC management. This paper also describes the empirical performance analysis of the proposed BFRA and AVRA by implementation using CORBA from the perspectives of the routing table construction, VPC provisioning and VPC reconfiguration. KeywordsATM Network Management, Routing, VP Reconfiguration, G.805, IP QoS, CORBA, SNMP, N O N 0-7803-5864-3 0 2000 IEEE Session Twenty ATM Network Management reason why ATM has enjoyed success in the Intemet backbone environment [3].In order to take the advantages of the capability of QoS guarantee of ATM and the capacity of diverse multimedia traffic delivery of IP, we construct IP network over ATM backbone using the ITU-T G.805 layering concepts. ITU-T G.805 defines the transmission technology independent transport network architecture with the layering and partitioning concept [I]. From the perspective of a layering concept, ATM backbone network takes the role of the server layer network and IP network also takes the role of a client layer network. All Routers in IP network are interconnected with ATM VPC provided by ATM VP Network Management System (ATM VP-NMS).The ATM backbone network is partitioned as a Sub-Network ( S N W ) according to the ITU-T G.805 partitioning concept that promotes a network scalability and narrows network management scope. However, it give a disadvantage that can not find a globally optimal route because of the successive SNW partitioning of network topology aggregation like Figure 1.