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In this paper, we propose a Web service based inter-AS (autonomous system) connection management architecture for QoS- guaranteed DiffServ provisioning. In the proposed architecture, the interaction between customer network management (CNM) and network management system (NMS), and the interactions among multiple NMSs are designed and implemented based on Web service architecture with WSDL, SOAP/XML and UDDI. The proposed architecture can be easily implemented in the early stage of MPLS network employment where the MPLS signaling is not mature yet, and provides efficient internetworking among multiple Internet Service Providers (ISPs) that is requested to provide end-to-end QoS-guaranteed differentiated services. [ABSTRACT FROM AUTHOR]

As a network & service provider, KT has long felt the necessity of integrating many of its OSS (Operation Support System) systems, and in 2003, KT finally developed a new system to serve its various maintenance activities. This system is called the NeOSS (New Operations Support System) System, which uses XML (Extensible Markup Language), EAI (Enterprise Application Integration) and Web service based on Microsoft's .NET platform technology. This paper shows the system architecture of the NeOSS-ADM(Access Domain Management), which is going to be developed using the .NET environment, service maintenance framework and the method of maintenance for NEs (network elements) for base BS. And this system will give more high quality service to customers and reduce the customer's complaints. Keywords: NGOSS, NeOSS, NeOSS-ADM, Proactive Service. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new approach to secure and easy-to-use remote access to networked appliances (NAs). Based on the proposed approach, we develop a system in which servers in an Internet service provider network and a residential gateway (RGW) in a home network play an important role, including secure communication. The system allows us to access NAs, using mobile phone and PC anytime and anywhere. Our emphasis is that the system is based on zeroconf protocols including UPnP, and only by connecting an NA to a RGW enables secure remote access. Another emphasis is deployability. A RGW that has been widely deployed in home networks and always operates for VoIP call serves the zeroconf protocols. Interoperability with both UPnP compliant and noncompliant NAs, together available in the marketplace, is also considered. We deployed the system and conducted a field trial in which approximately 1700 users took part in for four months. Empirical results in terms of the zeroconf protocols will be shown with future directions. [ABSTRACT FROM AUTHOR]

This paper intends to introduce the development of a terminal agent for QoS measurement that is suitable for an NGN environment, and to summarize the results of its performance test. Using the terminal agent for service quality measurement, it is possible to measure the QoE-based end-to-end service quality of voice phone, video phone, and VoD services. In addition, the terminal agent, installed in the user terminal (IP-based audio and video phones), as a software or hardware chip, measures the quality index for voice and video related multimedia services, such as R-value, MOS value, call success rate, one-way delay, jitter, packet loss, resolution. The terminal agent also applies the packet capturing method when using the actual service, and analyzes SIP, RTP, and RTCP protocol headers of the received packet. When the terminal agent was implemented in the IP video phone and compared with the performance of a general QoS measurement tool, there were barely any errors in the measurement value. It has also been identified that end-to-end service quality management, which is close to QoE, was possible. Keywords: QoS, QoE, QoS Measurement, SQM(Service Quality Management). [ABSTRACT FROM AUTHOR]

In this paper, we realize a DiffServ-based Multicast Router (DSMRouter) to provide the QoS adjustment for multicasting video transmission in the DiffServ network. To reach the QoS goals, the proportional fairness scheduling strategy is proposed for layered media flows, including I-frame, P-frame and B-frame flows, to determine the approximate reserved bandwidth. Additionally, the DSMRouter system dynamically changes the sending rates of various service queues to ensure that layered media packets with higher priority are always sent before those with lower priority. The results reveal that DSMRouter dynamically modify layered media's sending rates among different service classes according to the network situation. The experimental results of the DSMRouter system on DiffServ networks also reveal that layered media with higher priority have less packet loss. [ABSTRACT FROM AUTHOR]

Simulcast Technique can be used to diminish handoff rate and share resources among multiple relays in MMR system. Using dynamic grouping, simulcast technique can also rearrange traffic load. In this paper, we analyze group handoff generated by dynamic grouping in MMR system. Performance is evaluated in view of blocking and handoff call dropping probability. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new route optimization scheme (EDNS-MIPv6) for MIPv6 using the enhanced Domain Name System (DNS) together with local mobility management scheme to reduce the signaling delay. EDNS-MIPv6 alleviates the triangle routing problem and reduces both the signaling delay to the home network, and the home agent's processing load. [ABSTRACT FROM AUTHOR]

This paper shows that geographic information system can successfully solve TSP (travelling salesman problem). It has been done using a module of the designed and implemented by authors GISness system. Three algorithms for solving TSP are available, including the proposed by authors an hybrid algorithm called 2optGAM. The results of research show that the algorithm is very promising. [ABSTRACT FROM AUTHOR]

Many researches on context aware computing are carried out around the world. Among them, Context-Toolkit and Semantic Space provide separation of concerns between sensor and application. They make application developing easier. However, they have one problem that is lacking of simplicity in communication, compatibility and flexibility in building systems. To solve it, we propose one delivery and storage structure using standardized simple network management protocol which is useful to deliver, store and manage sensed information. We also verify that this architecture is efficient in wireless sensor network to deliver and store environmental information through an implementation of a SNMP agent. We confirm that this architecture with simplicity, compatibility and flexibility gives the efficiency to developing systems. Keywords: sensed information management, sensor network management, SNMP. [ABSTRACT FROM AUTHOR]

The growth of IPv4 Internet has been facing the infamous IP address depletion barrier. In practice, typical IPv4 Internet edge networks can be expanded by incorporating private addresses and NAT devices. In this paper, major limitations of NAT-expanded private networks are presented. Furthermore, a solution is proposed to encourage the mixed usage of private and public IP addresses in a single edge network domain. The solution comprises of two key ideas : super-subnet mask and shared NAT. Super-subnet mask removes the routing boundary between private and public hosts. Shared NAT saves public IP address resources by sharing them among several private networks. These ideas not only encourage the coexistence of heterogeneous address classes, but also lead to efficient sharing of global IP addresses. [ABSTRACT FROM AUTHOR]

In Ad hoc networks, malicious nodes can enter in radio transmission range on the routing path and disrupt network activity. Therefore, protecting from intrusion of malicious node and enhance data security is an important issue on Ad hoc networks. In this study, we provide a path hopping method based on reverse AODV (R-AODV). By reverse AODV, source node builds multipath to destination and adaptively hops available paths for data communications. Hopping paths can protect data from the intrusion of malicious nodes. We propose an analytic method to expect intrusion rate and a path hopping routing mechanism to implement simulation models using NS-2. Keywords: Path-hopping, reverse AODV, Ad hoc network security. [ABSTRACT FROM AUTHOR]

The configuration management of a sensor network composed of tens or up to thousands of nodes is difficult due to the limit of memory space and energy consumption. This paper presents an approach for dynamic reconfiguration of application modules in sensor networks based on Nano-Qplus. The version information from proposed methods is registered into NVSync (Nano-Qplus Version Synchronization), a node management tool. It dynamically reconfigures application modules on the nodes by synchronizing them with the node information map on the centralized repository. Our approach utilizes efficient usage of limited memory by systematically managing application modules of each node composed of sensor network. Additionally, it reduces unnecessary energy consumption by dynamic reconfiguration of application modules on the nodes. Therefore, it can flexibly deal with change of application environment of the node. [ABSTRACT FROM AUTHOR]

Distributed computing systems are continuously increasing in complexity and cost of managing, and system management tasks require significantly higher levels of autonomic management. In distributed computing, system management is changing from a conventional central administration, to autonomic computing. However, most existing research focuses on healing after a problem has already occurred. In order to solve this problem, an inference model is required to recognize operating environments and predict error occurrence. In this paper, we proposed a hybrid inference model - ID3, Fuzzy Logic, FNN and Bayesian Network - through four algorithms supporting self-healing in autonomic computing. This inference model adopts a selective healing model, according to system situations for self-diagnosing and prediction of problems using four algorithms. Therefore, correction of error prediction becomes possible. In this paper, a hybrid inference model is adopted to evaluate the proposed model in a self-healing system. In addition, inference is compared with existing research and the effectiveness is demonstrated by experiment. [ABSTRACT FROM AUTHOR]

The last few years, users want various services that fit their needs and preferences. Many services are provided at network edges and are increasing in number. The open framework is needed for efficient service management and uniform deployment of personal services at network edges. In this paper, we propose the open service framework, which can be implemented as a platform for the personal service at network edges by using Open Pluggable Edge Service (OPES) concept. The proposed framework is composed of Databases, Policy Repository, Rule Manager, Policy Adapter, Admission Manager, Operations Support System (OSS) Adapter and OPES-based Service Delivery Manager for the deployment of personalized and QoS guaranteed services in a standard way. In order to perform the feasibility of this platform, we have implemented a simple example and shown some its results. [ABSTRACT FROM AUTHOR]

DoS(Denial of Service) / DDoS(Distributed Denial of Service) attacks threaten Internet security nowadays. However, the current Internet protocol and backbone network do not support traceback to know attacker's real location. Many methods to defend DoS/DDoS attack have been proposed. However these kinds of methods cause network overhead because they use many packets to reconstruct an attack path. In this paper we propose effective probability marking methods and a pushback algorithm to reduce network overhead. [ABSTRACT FROM AUTHOR]

In this paper, several dynamic QoS solutions including Direct DiffServ, Admission-based Direct DiffServ, Indirect DiffServ, and Hybrid DiffServ are proposed to support largely emerging SIP-based P2P(Peer-to-Peer) and ASP(Application Service Provider) multimedia applications in DSL networks, most widely deployed as broadband access networks. The proposed solutions are designed to be based on standard COPS protocol which is simple and service-independent. [ABSTRACT FROM AUTHOR]

In this paper, we propose an open standard-based, intelligent service management platform that aims to provide a flexible and extensible platform for building intelligent home network services. To have greater flexibility and efficiency in managing home network services, we further propose an AAA proxy, a service provisioning, security agent, a sip proxy service, and others. We call this platform the IHSM (Intelligent Home Network Service Management) Platform, which consists of the ISMS (Intelligent Service Management System) and the ISMF (Intelligent Service Management Framework). [ABSTRACT FROM AUTHOR]

This paper proposes an efficient resource-optimal key pre-distribution scheme for providing improved security in wireless sensor networks. We exploit the advantages of two schemes with some modifications and combine our encoding scheme to get resource-efficiency and better security. [ABSTRACT FROM AUTHOR]

A wireless sensor network is a collection of devices limited in low-powered batteries, processing, communication bandwidth capabilities and low memory availability. Due to these constraints, most of security approaches used in wired networks cannot be applied directly in this environment. In this work, we present a hybrid protocol that treats the group key management scheme and the transparent cluster interconnection. The feasibility of this protocol was verified by simulation and we concluded that increasing the number of nodes in the network does not change the performance of the interconnection between any two clusters. [ABSTRACT FROM AUTHOR]

Over the past few years we have witnessed steady progress toward convergence in communications. We believe we are now witnessing convergence beyond just media transport. Further, abstract application level signaling technologies are poised for takeoff and will serve as the unifying fabric for multi-dimensional convergence. Our research shows that such a signaling mechanism known as "presence", combined with advances in namespace and security technology, will enable ultimate service innovations. Keywords: presence management, SIP, application layer signaling, network convergence. [ABSTRACT FROM AUTHOR]

In this paper, for the combination of DiffServ and RSVP, we propose traffic conditioning algorithm. Through the proposal, we expect the service quality improvement of real time application, especially voice traffic, by separation of other data traffic. [ABSTRACT FROM AUTHOR]

For an efficient role based access control using attribute certificate in highly distributed computing environments, we use a technique of structuring role specification certificates. The roles are grouped and made them into the relation tree. It can reduce management cost and overhead incurred when changing the specification of the role. Further we use caching of frequently used role specification certificate for better performance in case applying the role. And for the global space reduction, we also consider the issue of tree normalization. In order to be scalable distribution of the role specification certificate, we use multicasting packets. In the experimental section, it is shown that our proposed method is secure and efficient. [ABSTRACT FROM AUTHOR]

In this paper, an efficient neighbor AR (Access Router) discovery scheme and handoff procedure using neighbor information are proposed. It allows each AR and Mobility Anchor Point (MAP) to know neighboring ARs and MAPs, and therefore, a mobile node (MN) can perform the handoff process in advance, using the proposed handoff mechanism. It is important to note that the Inter-MAP domain handoff improvement of the proposed scheme is up to about 57% and 33% for handoff latency in comparison of the Hierarchical Mobile IPv6 (HMIPv6) and the Hierarchical Mobile IPv6 with Fast handover (F-HMIPv6), respectively. The proposed scheme is approximately two times better than the existing one in terms of the total signaling costs through performance analysis. Therefore, it is sufficiently satisfied with the requirements of real-time applications, and seamless communication is expected. [ABSTRACT FROM AUTHOR]

The explosive growth of new multimedia services over the Internet necessitates efficient network management. Improved network management systems are expected to simultaneously provide diverse multimedia traffic services and enhance network performance. In this paper, we propose a new online network management algorithm that implements adaptation, reservation, and call-admission strategies. Our online approach to network management exhibits dynamic adaptability, flexibility, and responsiveness to the current traffic conditions in multimedia networks. [ABSTRACT FROM AUTHOR]

This paper proposes a dynamic shared-memory packet buffer management algorithm for a protocol processor in a network terminal. The protocol processor is located in a network interface card (NIC). In general, two types of packet buffer management algorithms, static and dynamic, can be used in a NIC; the dynamic buffer management algorithms work better than the static ones for reducing the packet loss ratio. However, conventional dynamic buffer management algorithms do not provide even packet losses to all the applica-tions. Therefore, we propose an algorithm to enhance even packet losses and the proposed algorithm improves the packet loss ratio by 11.80% to 16.70% compared to other conventional dynamic algorithms. [ABSTRACT FROM AUTHOR]

Rapid evolution in ubiquitous systems is complicating its management. In the realm of ubiquitous computing, the domain specific ontologies are constructed manually by experts, which is quite a toiling task. We proposed to extract ontologies dynamically for ubiquitous systems. We also argue that the components of the software middleware are the specialized research areas with different subject orientation e.g. context reasoning, service discovery etc[1] and following an evolvable component oriented approach would let the components of the software evolve independently of other software components, while making them interoperable irrespective of versions and vendors. [ABSTRACT FROM AUTHOR]

This paper proposes a DiffServ-over-MPLS Traffic Engineering (TE) architecture and describes the implementation of its functional blocks on Intel IXP2400 Network Processor using Intel IXA SDK 4.1 framework. We propose fast and scalable 6-tuple range-match classifier, which allows traffic policing procedures to operate on per-flow level, and a scalable low-jitter Deficit Round Robin (DRR) scheduler that can provide bandwidth guarantees on LSP level. The proposed DiffServ-over-MPLS TE functional blocks have been implemented on Intel IXDP2400 platform for up to 4,096 flows mapped to L-LSPs, and can handle an aggregated traffic rate of 2.4Gbps. Keywords: QoS, DiffServ-over-MPLS, scalability, network processors. [ABSTRACT FROM AUTHOR]

In NGN, many transport-related technologies were considered. One technology discussed is ATM (Asynchronous Transfer Mode) based MPLS (Multi-protocol Label Switching) for its provisioning QOS (Quality Of Service) commitment, traffic management aspects and smooth migration to the BcN in Korea. In this paper, we present preventive congestion control mechanism that uses network signaling information for detecting and fuzzy control to a SC(Slim Chance) of LSP (Labeled Switched Path) in ATM based MPLS system. Proposed control can handle 208% call processing and more than 147% success call, than those without control. It can handle 187% BHCA (Busy Hour Call Attempts) with 100 times less use of exchange memory. Keywords: Congestion, MPLS, BcN, NGN. [ABSTRACT FROM AUTHOR]

Many research works address detection and identification of network anomalies using traffic analysis. This paper considers large topologies, such as those of an ISP, with traffic analysis performed on multiple links simultan-eously. This is made possible by using a combination of simple online traffic parameters and specific data from headers of selective packets. Even though large networks may have many network links and a lot of traffic, the analysis is simplified with the usage of Principal Component Analysis (PCA) subspace method. The proposed method proves that aggregation of such traffic profiles on large topologies allows identification of a certain set of anomalies with high level of certainty. Keywords: Network anomalies, Anomaly detection, Anomaly identification, Principal component analysis, Traffic analysis. [ABSTRACT FROM AUTHOR]

IP-based IMT Network Platform(IP2) is an ubiquitous platform supporting mobility using two step IP address mode converting - IP host address(IPha) and IP routing address(IPra) - in a backbone network. Mobile Node(MN) in IP2 maintains its state as either active or dormant state, which is transferred to active state through Paging process when communication is required. In this paper, we proposed a Paging method using agent to resolve the problem of the conventional Paging method which transmits the Paging messages to all cells in Location Area(LA) resulting in the excessive use of network resources. Performance evaluation of the proposed method using NS-2 showed that the usage of network resources becomes more efficient by reducing Paging loads, especially under the condition of increased nodes. [ABSTRACT FROM AUTHOR]

Recently, researchers have explored to provide a queue management scheme with differentiated loss guarantees for the future Internet. The Bounded Random Drop (BRD), known as the best existing scheme, is one of such efforts which guarantees strong loss differentiation to the level of traffic in the different service classes. Even though BRD has several benefits such as low complexities and good functionalities, we identify that it has some shortcomings such as low throughput, long queuing delays, and selection problem of optimal values of parameters. Specifically, the shortcomings stem from calculating drop probabilities based on the arrival rate estimation and dropping incoming packets randomly with calculated drop probabilities without considering the current buffer occupancy. A multiple queue management scheme based on differential drop probability, called MQDDP, is proposed to overcome BRD's shortcomings as well as support absolute loss differentiation. This scheme extends the original Random Early Detection (RED), recommended by IETF for next generation Internet gateways, into multiple class-based queues by deriving the drop probability equations based on a queueing model. We also compare MQDDP to BRD for high traffic intensity and show that MQDDP has the better performance in terms of packet drop rate. [ABSTRACT FROM AUTHOR]

In this work we propose an analytic framework for managing the optimal bandwidth required for a smooth playback of a stored video streaming service. First, we argue that the mean buffering delay in the node is minimized if the video packets are paced to a fixed interval at the beginning of the transfer. Second, we argue that an appropriate level of bandwidth has to be maintained so that neither buffer-underflow nor buffer-overflow occurs, via which a smooth playback of video stream can be maintained. From the numerical evaluation, we found that the paced packet stream experiences smaller delay than the original random packet stream. Next, we computed a range of bandwidth for a video stream so that neither buffer-underflow nor buffer-overflow occurs, and we showed that paced packet stream requires smaller bandwidth than the original random packet stream. [ABSTRACT FROM AUTHOR]

We have previously proposed a diffusion-type flow control mechanism as a solution for severely time-sensitive flow control required for high-speed networks. In this mechanism, each node in a network manages its local traffic flow on the basis of only the local information directly available to it, by using predetermined rules. In addition, the implementation of decision-making at each node can lead to optimal performance for the whole network. Our previous studies show that our flow control mechanism with certain parameter settings works well in high-speed networks. However, to apply this mechanism to actual networks, it is necessary to clarify how to design a parameter in our control mechanism. In this paper, we investigate the range of the parameter and derive its optimal value enabling the diffusion-type flow control to work effectively. [ABSTRACT FROM AUTHOR]

The Next Generation Network (NGN) has a multilayer logical construction. Network carriers use various tools in complex procedures to operate application servers on the NGN. We try to establish a method for operating application servers in a unified management environment. This method operates between the network layer, which manages applications. First, we select requirements to achieve a unified management environment for application server operation. Then, we select a test function and a monitoring function from operation functions, in an experiment to confirm the achievability of our method. We test the achievability of two application server functions, which supply web services in the experiments. Our method supplies these functions without programming and manual procedures. [ABSTRACT FROM AUTHOR]

The NGN convergence services will play an important role to consolidate the deployment of NGN at the initial phase. At the initial stage, scenario-based approach is expected to act as an efficient way to pre-design before the actual implementation of NGN, the subject for providing the convergence services to the customers. This paper first proposes a deployment model of the NGN convergence services. In this model, NGN-Service Providers (NGN-SP) interact with Service Coordination Function of NGN Service Stratum whereas NGN convergence service terminal equipments (NGN-CTE) provide convergence services to the end users after procedures in End User Service Composition Function. A service composition scenario for the convergence services will be introduced, using the model, to show the usefulness of the proposed deployment model to construct new convergence services on this scenario-based approach. Keywords: NGN, NGN-SP, NGN-CTE, convergence. [ABSTRACT FROM AUTHOR]

In next-generation wireless networks, OFDM is a potential key technology. Subcarriers in the OFDMA networks are scarce and valuable, operators should manage them efficiently by radio-resource management function. Several OFDMA subcarrier-allocation schemes and performance-evaluation methods have been widely studied, but very few studies focused on managing call blocking probability (CBP) and bandwidth utilization (BU). CBP and BU are two important performance measures, which respectively represent the quality of service for subscribers and the profit of operators. This paper proposes an evaluation model to accurately predict the subcarrier-allocation performance, especially in consideration of the CBP and BU. Theoretical and simulation results indicate that the model works. In addition, the CBP and BU are adopted to solve a subcarrier utilization-optimization problem, which can be applied in network planning and re-planning processes. The optimization problem uses given traffic load and specified maximum CBP constraint to maximize the BU by discovering the optimal number of subcarriers in a base station. Finally, operators may utilize the results to manage their subcarriers flexibly, and to improve their profitability. Keywords: Performance management; OFDMA; Subcarrier allocation; Utilization optimization. [ABSTRACT FROM AUTHOR]

Time-Slotted Optical Burst Switching (TS-OBS) is one of the most promising next-generation transport network technologies. This paper proposes a time-slot assignment procedure using centralized control for TS-OBS networks. Our scheme attempts to improve burst contention resolution and optical channel utilization. Analysis and simulation results show that the channel utilization of the TS-OBS network is improved markedly at the expense of ingress buffering delay. Keywords: time-slotted optical burst switching, centralized resource allocation. [ABSTRACT FROM AUTHOR]

In convergence telecommunication environment, Business Agility plays very important role in the OSS(Operation Support System) when telco provide new merged services to customer on time. But, the OSS also becomes more and more complicated to know even what part of it should be fixed for adopting new services. This paper proposes SOA-based OSS architecture for telecommunication services in order to cope with this situation. We present the designing method of services of SOA and architecture for OSS by investigating the architectural issues of the unit of derived service elements from OSS and designing the most suitable architecture of it. By adopting the represented architecture for OSS, telco can provide new convergence service to customers faster than the competitor on the market. Keywords: SOA, NGOSS, service, convergence, architecture. [ABSTRACT FROM AUTHOR]

As the network technology has been developed, the Next Generation Internet (NGI) such as Internet2, KOREN, KREONET2 and etc has been deployed to support bandwidth of Giga bps. And, various applications such as the video conference, the tele-surgery and etc that require high bandwidth has been developed and operating on the NGI, especially KOREN and KREONET2 in Korea. When the applications are operating and happen to face some problems, various tools for traffic measurement are usually used to analyze them, and provide traffic information in each link on total flow path or other metrics such as end-to-end delay, jitter and etc in most cases. However, although with these tools most of network problems can be properly analyzed, the problem in the user's view point can not be resolved so that which part of networks and/or which ones among user's systems and nodes on the flow path cause the problems for the user's flow is not discriminated Therefore, this paper designs a end-to-end performance monitoring system for the user's flow that the user can access performance data for user's flow on the flow route, and describes the experience about deployment on KOREN. [ABSTRACT FROM AUTHOR]

Systems designed to be self-healing are able to heal themselves at runtime in response to changing environmental or operational circumstances. Thus, the goal is to avoid catastrophic failure through prompt execution of remedial actions. This paper proposes a self-healing mechanism that monitors, diagnoses and heals its own internal problems using self-awareness as contextual information. The self-management system that encapsulates the self-healing mechanism related to reliability improvement addresses: (1) Monitoring layer, (2) Diagnosis & Decision Layer, and (3) Adaptation Layer, in order to perform self-diagnosis and self-healing. To confirm the effectiveness of self-healing mechanism, practical experiments are conducted with a prototype system. [ABSTRACT FROM AUTHOR]

For QoS guaranteed DiffServ-over-MPLS connection provisioning in multi-domain networks, the managed objects in each domain should be globally standardized and publicly accessible by other NMSs. And each NMS participating in the inter-domain networking should negotiate with other NMSs for end-to-end service provisioning. In this paper, we propose SLA negotiation by COPS protocol and design the managed objects by expanding existing experimental DMTF CIM MOFs. We propose service location protocol based directory agent to register/discover the NMSs' that participate in the multi-domain TE-LSP connection provisioning. For better performance, we design the multi-threaded provider implementations on OpenPegasus WBEM platform. The detailed implementations of the providers with performance analysis are explained. [ABSTRACT FROM AUTHOR]

Conditional Access System (CAS) performs entitlement management to make only legitimate subscribers watch pay-services. Generally, CAS uses passive entitlement management to fulfill that entitlement control, and various schemes are existed for that. Among them, Tu introduced two schemes in [1], which are the simple scheme and complete scheme of four levels hierarchy. The advantage of the simple scheme of four levels hierarchy is a small key generation and encryption load for a CAS, but it is not good for the dynamic entitlement management. On the other hand, the complete scheme of four levels hierarchy is good for the dynamic entitlement management, but key generation and encryption load for CAS is considerable when it is compared to the simple scheme. In this circumstance, we proposed a novel scheme, which is an active entitlement key management. The proposed scheme not only performs the dynamic entitlement management very efficiently, but also generates and encrypts keys with a small load for CAS, which is just the same as the load of the simple scheme. Keywords: Conditional Access System, Key Management, Digital TV Broadcasting System. [ABSTRACT FROM AUTHOR]

In Grid service, resource management is important to support capability for good quality and efficiency for the computing and storage service. In order to provide this resource management which has low complexity, high performance and high throughput with guaranteeing QoS, the well defined network resource management architecture and scheme have to be considered. Thus, we propose the integrated grid resource management architecture based on QoS-constraint policy and we derive cost-sensitivity policy enforcement procedure which can be applied to this architecture in Grid network. Finally, the results show that the proposed scheme outperforms the conventional scheme in the network performance such as a blocking rate of resource request messages and the operation cost. [ABSTRACT FROM AUTHOR]

Setting up an IDS architecture on ad-hoc network is hard because it is not easy to find suitable locations to setup IDS's. One way is to divide the network into a set of clusters and put IDS on each cluster head. However traditional clustering techniques for ad-hoc network have been developed for routing purpose, and they tend to produce duplicate nodes or fragmented clusters as a result of utilizing maximum connectivity for routing. Most of recent clustering algorithm for IDS are also based on them and show similar problems. In this paper, we suggest to divide the network first into zones which are supersets of clusters and to control the clustering process globally within each zone to produce more efficient clusters in terms of connectivity and load balance. The algorithm is explained in detail and shows about 32% less load concentration in cluster heads than traditional techniques. Keywords: Intrusion detection architecture, Ad-hoc Network, Clustering. [ABSTRACT FROM AUTHOR]

In any (D)DoS attack, invaders may use incorrect or spoofed IP addresses in the attacking packets and thus disguise the factual origin of the attacks. Due to the stateless nature of the internet, it is an intricate problem to determine the source of these spoofed IP packets. This is where; we need the IP traceback mechanism i.e. identifying the true source of an IP datagram in internet. While many IP traceback techniques have been proposed, but most of the previous studies focus and offer solutions for DDoS attacks done on IPv4 environment. Significant differences exist between the IPv4 and IPv6 Networks for instance, absence of option in basic IPv6 header. Thus, the mechanisms of IP Traceback for IPv4 networks may not be applied to IPv6 networks. In this paper, we extended our previous work i.e. PPM for IPv6 and removed its drawback by using Policy Based IP Traceback (PBIT) mechanism. We also discussed problems related to previously proposed IPv4 traceback schemes and practical subtleties in implementing traceback techniques for IPv6 networks. Keywords: DDoS, Traceback, IPv6, Network Security. [ABSTRACT FROM AUTHOR]

Web Services and Service-Oriented Architecture (SOA) has been playing an important role as a middleware for interoperable transactions such as Business-to-Business and Enterprise Application Integration. Popular Web Services frameworks, such as Apache Axis, did not consider the Quality of Service (QoS), though these aspects are high demands in practice. In this paper, we present a framework supporting QoS built on the top of Axis. The framework is transparent with developers on both client and server side, and supports QoS including performance, accessibility, reliability, and security for SOA-based transactions. The design and implementation of our framework provide an easily integrated and flexibly extended approach to SOA-based applications. The key features and implementation methodology are described, with scenarios provided as usage examples of the framework. [ABSTRACT FROM AUTHOR]

In this paper, we model the end-to-end QoS provisioning mechanisms in the WLAN and 3GPP interworking network. For the end-to-end QoS guaranteed service, we model the control plane and user plane considering the WLAN and 3GPP interworking network. And we propose the QoS parameter/class mapping and DPS packet scheduler. By the simulation results, DPS can provide the low end-to-end delay of voice traffic, even though a traffic load increases by 96%. Especially, the end-to-end delay of voice is much smaller when the QoS parameter/class mapping and DPS are applied to the interworking network.This work was supported by the second stage of Brain Korea 21 (BK21) Project in 2006. [ABSTRACT FROM AUTHOR]

We propose a new method to determine the optimal TXOP duration (TD) of scheduling algorithm for VBR traffics that guarantees delay and loss probability in IEEE 802.11e HCCA. In this algorithm, the TXOP Duration for each Traffic Stream (TS) is determined by the number (N) of packets to be transmitted during a TXOP duration, which is found by analyzing M/DN/1/N×l queueing system where the delay bound of the TS is l times the Service Interval having D length. Numerical results show that the number of admitted TSs with guaranteed loss probability by new method is greater than the number of admitted TSs by other known schemes. [ABSTRACT FROM AUTHOR]

Despite the importance of seamless connectivity in ubiquitous computing, research for seamless connectivity has not been considered properly. To provide seamless connectivity, this paper proposes an application execution model for seamless services with an intelligent context-aware handoff scheme based on context information, such as user intentions and application requirements as well as issues of network layer. In this paper, we define several profiles reflecting various context informations and design basic modules organizing middleware architecture for seamless service management and efficient vertical handoff (VHO) management. Consequently, the proposed seamless service management with context-aware handoff scheme provides service continuity in ubiquitous computing environment by preventing unnecessary handoffs, changing application service modes adaptively, and eventually maintaining optimal network configuration. And also simulation results show about 38% enhanced performance in the processing rate, about 13% enhanced performance from service continuity, and about 29% enhanced performance in the processing time, compared with conventional schemes. [ABSTRACT FROM AUTHOR]

In this study, an adaptive handoff algorithm with a dynamic hysteresis value, based on the distance between the mobile station and the serving base station, is proposed for cellular communications. Handoff probability is calculated to evaluate handoff algorithms analytically. The proposed handoff algorithm is compared with an algorithm with fixed hysteresis, an algorithm using both threshold and hysteresis, and a handoff algorithm based on distance and hysteresis. Performance is evaluated in terms of the average number of handoffs, average handoff delay, standard deviation of handoff location, average signal strength during handoff, and probability of link degradation. Numerical results and simulations demonstrate that the proposed algorithm outperforms other handoff algorithms. The effect of distance error is also discussed. [ABSTRACT FROM AUTHOR]