Won-Kyu Hong

Network management with bounded flooding routing algorithm to ensure IP QoS over ATM virtual path network

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 a 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 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.

Distributed Connection Management Architecture for Optimal VPC Provisioning on Hierarchical ATM Transport Network

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.

Hierarchical VP restoration management system for a reliable ATM backbone network

This paper proposes a distributed ATM VP PVC restoration framework with the dynamic rerouting schemes in a hierarchical transport network. The rerouting algorithm aims to provide rapid ATM VP PVC restoration in the case of fault or performance degradation in terms of maximization of network resource utilization and satisfaction of the end users QoS requirement.

The CORBA-based unified event management framework in multi-layer networks

An efficient integrated event management is a great concern to a telecommunications industry. An integrated event management across multi-layer networks is much more complex than that across a specific layer network. Although there are several event management frameworks [Ericsson Research Canada March (2000); Integrated Network Management - Proceedings of the Fourth International Symposium on Integrated Network Management (1995) 290-301; Integrated Network Management - Proceedings of the Fourth International Symposium on Integrated Network Management (1995) 278-289], each of them is designed to apply only a specific single layer network. The frameworks are the cause of a lack of scalability and of the difficulties of integrated event management of multi-layer networks. On the other hand, CORBA Notification Service (NS) [OMG, CORBA Services: Common Object Service Specification March (1995); OMG, The Common Object Request Broker: Architecture and Specification July (1995)] is a promising event propagation platform to build an integrated event management for multi-layer networks, but its performance is not sufficient for bulk events in such networks. This paper proposes the unified event management framework that can uniformly be applicable to multi-layer networks of ATM, Frame Relay (FR) and IP without any customization or modification. In order to define such a framework, this paper proposes a common network model and an event information model that is commonly applicable to the multi-layer networks, which identifies the meaning and relationship of information manipulated by the framework. This paper also suggests an event queue management scheme to improve the insufficient performance of CORBA NS stemmed mainly from its persistency property. Replacing this with the proposed queue management scheme and comparing the event management performance of the framework with that of CORBA NS, this paper will show that former gives a much higher event propagation performance than that of the latter.

BFRA: bounded flooding routing algorithm for provisioning the globally optimal route in a hierarchical ATM network

ATM virtual path (VP) contains bundles of virtual channels (VCs). A VP layer network can be used as a server layer network of VC layer networks and each VC layer network can be a client layer. Therefore, the effective provision of VC services can be achieved by the more optimal routing scheme of the VP layer network. However, the traditional hierarchical routing scheme of PNNI signaling protocol does not provide the globally optimal route in hierarchical transport network due to its successive network partitioning and topology abstraction. We propose a new VP routing scheme suitable for the national wide hierarchical transport network and a network model suitable for the scalable VP network management system. The routing algorithm can provide the globally optimal route in the hierarchical network environment from the perspectives of maximization of network resource utilization and satisfaction of the end users QoS requirement. In addition, we describe the implementation model of the ATM virtual path network management system (VP-NMS). Lastly, we show the routing performance evaluated in the high speed information network (HSIN) of Korea Telecom.

An integrated network management system for provisioning the efficient ATM over ADSL service

This paper describes an integrated network management system for provisioning the efficient ATM over ADSL service. There are two distinct networks of ATM and Internet. Most of routers in the Internet are connected with WDM. The network access server (NAS) in the Internet provides the Internet access service for ATM over ADSL subscribers. The ATM network takes the roles of the backbone network for the ATM PVC and SVC services and the access network for the ATM over ADSL service. Proposing an integrated network management system for the ATM over ADSL service, this paper defines a unified network model composed of two fragments of the topology and the connectivity taking into account the maximization of scalability. It is designed with the ITU-T G.805 layering and partitioning concepts and the RM-ODP information viewpoint. In addition, this paper proposes the distributed computational model of the ATM over ADSL network management system using the RM-ODP computational viewpoint and the TMN functional decompositions of FCAPS taking into account the functional distribution and the modularity. In addition, this paper describes the scenario for providing the ATM over ADSL service.

ANMP: Active Network Management Platform for Telecommunications Applications

The ability to rapidly create and deploy new services in response to the market demands will be the key factor in determining the success of future network service provider. There are several works to meet this requirement in the field of active network management [1,2,10- 15]. However the traditional active network management is essentially based on the revision of network elements, which subsequently delays the provision of new service due to the hardware revision. This paper proposes an Active Network Management Platform (ANMP) for rapid provisioning of new telecommunications network management functions as we locate most of the necessary control functions of active network management not on the network elements but on the ANMP. To do this, this paper proposes the reference model of active network management composed of three hierarchical levels: the network element level, the active network management platform level based on CORBA, and the network management level. Based on the reference model, we propose the detailed system architecture for the active network management platform and programmable APIs designed by CORBA IDL [5] for provisioning of new service, modification of existing service, withdrawal of obsolete service and authentication. Lastly, this paper verifies the performance of the proposed ANMP with the implementation using the IONA Orbix [4] through the case study of the reconfiguration of the ATM VP tunnels connecting routers.

Integrated network management framework for ATM-over-ADSL service

In this paper, we describe an integrated network management system for ATM over ADSL service provisioning. There are two distinct networks of ATM and Internet. Most of routers in Internet connected with WDM. The Network Access Server (NAS) in the Internet provides the Internet access service for the ATM over ADSL subscriber. The ATM network takes the roles of backbone network for the pure ATM PVC and SVC services and the access network for the ATM over ADSL service. In order to define the generic network model that can be commonly applicable for the backbone network for pure ATM service and the access network for ATM over ADSL service taking into account the scalability, we suggest two fragments of the topological fragment and connectivity fragment to maximize the scalability in accordance with the ITU-T G.805 layering and partitioning concepts and the RM-ODP information viewpoint. In addition, we propose the distributed computational model of the ATM over ADSL network management system using the RM-ODP computational viewpoint and TMN functional decomposition of FCAPS taking into account the functional distribution and the modularity. Lastly, we describe the scenario for providing the integrated ADSL service.

Fault management system for reliable ADSL services provisioning

A number of ADSL subscribers are explosively increasing every year. The ATM over ADSL gives us a new paradigm for Internet access service using existing copper cable. An ATM network takes the role of access network for providing the Internet access service using the ATM over ADSL. However, it is very difficult for network service provider to manage the large-scale ATM access network in uniform in terms of the stabilized Internet access service provision using the ATM over ADSL model. We logically divide the ATM access network into two domains from the perspective of fault management. The first domain is composed of DSLAMs and the seconds one is composed of the pure ATM switches. This paper proposes two level fault management schemes for ATM over ADSL service provision in terms of TMN functional layering: one is the fault management in terms of the network management layer (NML) and the other is one in terms of the service management layer (SML). We also describe the experience learned from the network management under the real network applying the proposed fault management schemes.