Dong-Sik Yun

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.

Design of NGOSS TSA Using Web Services Technologies

To reduce frequent changes and upgrades of management systems, we need a guideline of OSSs 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 services- based TSA in accordance with the TNA requirements.

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.

Design and implementation of Web Services-based NGOSS technology-specific architecture

To cope with frequent changes and functional additions of operation and support systems (OSSs), a guideline of OSS’s architecture and development methods is needed. TeleManagement Forum has provided Next Generation Operations Systems and Software (NGOSS) technology-neutral architecture (TNA), which describes major concepts and architectural details of the NGOSS architecture in a technologically neutral manner. The TNA can be mapped onto technology-specific architectures (TSAs) using specific technologies such as Extensible Markup Language, Java, and Common Object Request Broker Architecture. Web Service, a distributed and service-oriented computing technology, can be also applied to NGOSS TSA. In this paper, we provide a design and implementation of Web Services-based TSA in accordance with the architectural principles of TNA and the performance evaluation of our proposed system. Our work can be used as a guideline for anyone planning to develop a Web Services-based NGOSS TSA.

Towards realization of web services-based TSA from NGOSS TNA

To avoid frequent changes of OSSs 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.

Association analysis of customer services from the enterprise customer management system

The communications market has seen rising competition among businesses. While securing new customers is still important, it is more crucial to maintain and manage existing customers by providing optimized service and efficient marketing strategies for each customer in order to preserve existing customers from business rivals and ultimately maximize corporate sales. This thesis investigates how to obtain useful methodologies for customer management by applying the technological concepts of data-mining and association analysis to KTs secure customer data.

A Replication Architecture of Central Inventory Database

This thesis aims to identify limits and constraints of operation support system built on central inventory database, suggest a replication architecture intended to address such limits and constraints, derive implementation methodologies and compare their merits/demerits to propose a replication architecture of central inventory database better aligned to the requirements of operation support systems.

A Hierarchical LSP Management Architecture for MPLS Traffic Engineering

In this paper, we propose a scalable Label Switched Path (LSP) management architecture for Multiprotocol Label Switching (MPLS) traffic engineering using a hierarchical network model. MPLS introduces the concept of a label hierarchy to support scalability by lessening the complexity of transit routers for the computation of complete routing tables. However, this hierarchical network model creates a critical disadvantage in providing a globally-optimal route because of topology abstraction or aggregation. This paper proposes a hierarchical routing scheme that can provide a globally-optimal route in hierarchical MPLS networks using propagation from the Condensed Subordinate Route Information (CSRI). CSRI is summarized route information among border nodes in the lower layer network and is reflected in the process of the LSP path computation in the higher layer network. We also propose the algorithms for generation of CSRI, for reflection CSRI to higher layer network topology, and for computation of an optimal LSP in a higher layer.

A configuration algorithm for provisioning of cell-based MPLS network

This paper proposes a configuration algorithm of multipoint-to-point connection for facilitating VC merge concept in an MPLS over ATM network. This configuration solves two major problems: determining the most reasonable candidate ATM switch served as an ATM-LSR under the complex ATM network topology; and providing the most reasonable multipoint-to-point connections with regards to network resource utilization. This algorithm is therefore subsequently composed of two procedures: ordering and backtracking. The ordering algorithm is for determining the orders of link and node taking the routing metrics of available bandwidth delay and hop count into account. The backtracking algorithm is to determine the optimal multipoint-to-point route based on the order information allocated by ordering algorithm. We evaluate the proposed algorithms under the operational network environment of KT.

A configuration algorithm for supporting VC-merge concept under the cell-based MPLS network

This paper proposes a configuration algorithm for determination of best VC-merge point under the cell-based MPLS network. This configuration algorithm solves two major problems: determining the most reasonable candidate ATM switch served as an ATM-LSR under the complex ATM network topology; and providing the most reasonable multipoint-to-point connections for deployment of cell-based MPLS network taking into account network resource utilization. This algorithm is subsequently composed of two procedures: ordering and backtracking. The ordering algorithm is for determining the orders of link and node taking the routing metrics of available bandwidth delay and hop count into account. The backtracking algorithm is to determine the best multipoint-to-point route based on the order information allocated by ordering algorithm. In addition, this paper describes the performance evaluation result of the proposed algorithms under the operational network environment of KT (Korea Telecom).