Seung-Hwa Chung

A flow-based method for abnormal network traffic detection

One recent trend in network security attacks is an increasing number of indirect attacks which influence network traffic negatively, instead of directly entering a system and damaging it. In future, damages from this type of attack are expected to become more serious. In addition, the bandwidth consumption by these attacks influences the entire network performance. This paper presents an abnormal network traffic detecting method and a system prototype. By aggregating packets that belong to the identical flow, we can reduce processing overhead in the system. We suggest a detecting algorithm using changes in traffic patterns that appear during attacks. This algorithm can detect even mutant attacks that use a new port number or changed payload, while signature-based systems are not capable of detecting these types of attacks. Furthermore, the proposed algorithm can identify attacks that cannot be detected by examining only single packet information.

End-User Driven Service Creation for Converged Service of Telecom and Internet

Convergence and user-centricity are the leading trends in telecom network. The service creation scheme is changing to realize these trends. This paper describes the end-user driven service creation method for converged service over telecom and Internet domain. The proposed SCE fulfills the general SCE requirements and also comes up with the network trend to user-centricity and the network evolution towards convergence. The advantage of our approach comes from web based service creation and execution environment to satisfy end-users requirements and encourage users participation. Using our SCE, end- users can create their own service applications and use them anytime and anywhere through their personal devices.

Detection and analysis of packet loss on underutilized enterprise network links

ISPs and enterprises usually overprovision their networks as a means of supporting QoS. In spite of that, the service quality of QoS-sensitive applications such as VoIP, video conferencing and streaming media may not be up to expectations. We believe this is due to sporadic but non-negligible packet losses due to traffic bursts even in underutilized links. Our earlier work attempted to detect and analyze packet losses in underutilized links in an enterprise network environment using SNMP. This paper presents an extension of our earlier work by attempting to detect and analyze packet loss at finer granularity of time scale. We have developed a passive traffic capturing system, which can provide smaller time scale analysis of packet loss. We have analyzed the data and identified parts that are representative of packet loss across various time scales: 10 milliseconds, one second, 10 seconds and one minute. Analysis reveals that packet losses on underutilized link do occur due to bursty traffic packets in a small time scale. We also present analysis of other traffic properties such as packet size distribution and flows for the packet loss.

Efficient offering Service Creation Experience Environment for Open Service

Today, developers can create new services by simple mouse clicks on the tools. This shows SCE is becoming smart that means more automatic and requires less human interaction. IT developers who may not have the specific knowledge of telecommunication network can create open services. For that, the scope of SCE is becoming wider. These days, SCE required more than just simplifying and fast service creation. SCE needs to explain explicitly how to be used and make developers to understand well the outcome. This paper shows the efficient offering methods of open service creation experience environment

Developing a Knowledge Management System Using an Ontological Approach in Global Organization

This paper introduces an ontology-based knowledge model for knowledge management. This model can facilitate knowledge discovery that provides users with insight for decision making. The users requiring the insight normally play different roles with different requirements in an organization. To meet the requirements, insights are created by purposely aggregated transactional data. This involves a semantic data integration process. In this paper, we present a knowledge management system which is capable of representing knowledge requirements in a domain context and enabling the semantic data integration through ontology modeling. The knowledge domain context of United Bible Societies is used to illustrate the features of the knowledge management capabilities.

RSS Delivery Architecture for Multi-User Terminals Using Push Service

Web information search technique has been evolved from simple hyper text link to RSS technique that extracts information from the web, which is useful for the user, in XML format. In the case of telecommunication network, there was SMS service that sends/receives messages. But SMS service has the limitation, so Push service has been focused for the face of the converging internet to the telecommunication network. This paper proposes RSS delivery architecture using RSS relay server that monitors updated new contents and distributes them using Push service to registered multi-user terminals.

SCE Library Implementation for Parlay X APIs Working on both MS .NET & Java open platform

Today, converging services are the hot issue in everywhere. The services have become more dynamic and needed to be created faster. To open the telecommunication network functions to other network Parlay X has appeared and this international standard uses Web services technique. In this paper, we show the implementation of SCE Library called Toolkit Library for Parlay X APIs and also for useful internet services. Toolkit Library is tested and verified on Parlay X gateway simulator. Parlay X gateway can work on various platforms and mostly used platforms are MS .NET framework and Java open platform. Toolkit Library is implemented to work for both MS .NET framework and Java open platform based gateways. For the result we show the demonstration of Toolkit Library.

A Semantic Mapping Representation and Generation Tool Using UML for System Engineers

To address the problem of semantic heterogeneity, there has been a large body of research directed to the study of semantic mapping technologies. Although various semantic mapping technologies have been investigated, facilitating the process for domain experts to perform a semantic data integration task is not an easy task. This is because one is required not only to possess domain expertise but also to have a good understanding of knowledge engineering. This work proposes an abstract semantic mapping representation using UML for undertaking ontology mapping. The aim is to enable domain experts (particularly system engineers) to undertake mappings using the proposed UML representation that they are familiar with, while ensuring accuracy and ease of use of the automatically generated mappings. The proposed UML representation is evaluated through usability experiments (undertaken by system engineers) using a developed tool that was developed to implement the propose approach. The results show that the participants could correctly undertake the mapping task using the proposed UML representation and that the tool generated correct and executable mappings.

SCE Library Implementation for Creating Networks Converged Mashup Service

Open APIs make the developer, who does not have the specific knowledge of the network, create a service easier and faster. However, the developer still needs some knowledge of each APIs and programming skill in order to use this kind of APIs. For this, the SCE (Service Creation Environment) tool in which developers can easily use APIs was developed. Through the SCE, many number of general IT developers can create services simply with the minimum knowledge of the network and the understanding about the offered APIs. In this paper, we describe the implementation steps and the verification of the SCE library that can produce the mashup service composed by the parlay X API, the Web 2.0 API, and the utility API.

The investigation and classifying the web traffic delay & Solution plans presentation

As the number of the Internet users increase, various services on the Internet increases, too. Particularly, there were much effort for resolving the problem of Web traffic delay occurring due to the above reason. The increment of the Web traffic is noticeably increased due to the Web service which comes to have high capacity like a multimedia. In this paper, the Web delay has been classified. If we optimize each part of the classification and merge it, it will be the most optimized solution to solve the Web traffic delay. This paper presents the solution plans about expanding network bandwidth, distributing bandwidth by router, caching, designing the position of DNS root servers, Web packet retransmission time, and using ToS field. This paper is written on the assumption that the Web traffic has the first priority than the other traffics on the Internet. To reduce all the traffic delay, further studies are required.