Management Enabling the Future Internet for Changing Business and New Computing Services

Traffic traces captured from backbone links have been widely used in traffic analysis for many years. By far the most popular use of such traces is

replay

where conditions and states of the original traffic trace are recreated almost identically in simulation or emulation environments. When the end target of such research is detection of traffic anomalies, it is crucial that some anomalies are found in the trace in the first place. Traces with many real-life anomalies are rare, however. This paper pioneers a new area of research where traffic traces are engineered to contain traffic anomalies as per user request. The method itself is non-intrusive by retaining the IP address space found in the original trace. Engineering of several popular anomalies are shown in the paper while the method is flexible enough to accommodate any level of traffic trace engineering in the future.

By the end of 2008, China has 298 millions of Internet users served by 214 ISPs. But little is known to researchers about the details of these ISPs. In this paper, we try to understand web hosting utility of Chinese ISPs. After a brief introduction to ISPs in China, we use a simple and general method to uncover the web hosting information of ISPs including websites and web pages they host. We present a metric to evaluate the web hosting utility based on a new model which relies on public available data. Finally, a ranking of Chinese ISPs is given according to their web hosting utility. We analyze this ranking from the point of view such as IP allocation and geographical features. We believe that results of this work are not only helpful for researchers to understand networks in China, but also beneficial to interdomain capacity planning in China.

As network traffic is dramatically increasing due to the popularization of Internet, the need for application traffic classification becomes important for the effective use of network resources. In this paper, we present an application traffic classification method based on fixed IP-port information. A fixed IP-port is a IP, protocol, port triple dedicated to only one application, which is automatically collected from the behavior analysis of individual applications. We can classify the Internet traffic accurately and quickly by simple packet header matching to the collected fixed IP-port information. Therefore, we can construct a lightweight, fast, and accurate real-time traffic classification system than other classification method. In this paper we propose a novel algorithm to extract the fixed IP-port information and the system architecture. Also we prove the feasibility and applicability of our proposed method by an acceptable experimental result.

CoMPACT monitor that we have proposed is new technique to measure per-flow quality of service (QoS). CoMPACT monitor provide scalable measurement of one-way delay distribution by the combination of active and passive measurement. Recently, a new probing method for improving the accuracy of simple active measurement have been proposed. In this paper, we adopt the new probing method as active measurement of CoMPACT monitor, and show that the combination improves the accuracy of measurement remarkably for UDP flows.

Patching of applications on servers and PCs is a significant source of expense and frustration for IT staff. Organizations are concerned that patches will negatively impact the stability of their existing applications, and this concern results in significant delays in applying patches to publicly announced vulnerabilities of the applications. While Tracing based Pre-patch Impact Analysis method (T-PIA) is an effective way of measuring the actual impact of recent patches on the applications, it causes large storage and bandwidth usage of servers and PCs running the applications. We propose and evaluate a method to reduce such usage caused by T-PIA. Compared to the existing method, our method reduces storage and bandwidth usage by 83 and 89%, respectively. This verifies the ability of our method to reduce such usage.

As the scale of IP networks becomes larger, network management becomes more complex and the turn-around time of fault recovery is longer. This is because there are problems in adopting current essential tools for network management, such as a ping, Traceroute, and Simple Network Management Protocol (SNMP) to large-scale IP networks. We have been investigating ways to improve the performance of these tools, and proposed a high-speed ping and showed its advantage. For this paper, we propose and evaluate a high-speed traceroute method for collecting topology information from large scale networks. Our method is used to increase the speed of network topology collection to reduce topology-searching packets, which are sent in excess using the current traceroute method, as well as adopting our high-speed ping technology. In terms of reducing packets, our method can be used to send these searching packets to end points first (with the current traceroute method, they are sent last), detect nodes on the shared routes to those end points, and send searching packets to these nodes only. By implementing the above, we show that our proposed method can be used to reduce searching packets by 70% and the time to collect topology information by 95% compared with the current traceroute.

In order to improve the quality of Internet service, it is important to quickly and accurately diagnose the root fault from the observed symptoms and knowledge. Because of the dynamical changes in service system which are caused by many factors such as dynamic routing and link congestion, the dependence between the observed symptoms and the root faults becomes more complex and uncertain, especially in noisy environment. Therefore, the performance of fault localization based on static Bayesian network (BN) degrades. This paper establishes a fault diagnosis technique based on dynamic Bayesian network (DBN),which can deal with the system dynamics and noise. Moreover, our algorithm has taken several measures to reduce the algorithm complexity in order to run efficiently in large-scale networks. We implement simulation and compare our algorithm with our former algorithm based on BN (ITFD) in accuracy, efficiency and time. The results show that our algorithm can be effectively used to diagnose the root fault in high-level applications.

Optical IP services such as FTTH have been growing rapidly, leading to an urgent need to manage the optical fiber network from the central office. We have developed an optical-fiber distribution facility called an IDM. However, the changing FTTH environment means we need further efficiency and cost-effectiveness for network construction and operation work. This paper proposes a novel optical-fiber network management system for the IDM that realizes reducing working time, less skilled work and eliminating human error. This system consists of two technologies with control software, namely optical distribution identification technology using RFID, and automatic navigation technology using an LED and DB. In this paper, we describe optimized work flows for installation and removal work. Moreover, we achieved a reduction of up to 48 % in working time with less skilled workers and accurate DB management by using our proposed system.

Mobile nodes in the integrated network of infrastructure networks and mobile ad hoc networks need an efficient registration mechanism since they register with Internet gateway via wireless multiple hops. Tree-based mobility management is highly dependable in that mobile nodes register with Internet gateway along tree paths from itself up to a gateway without using flooding. In this paper, we introduce a new method using a virtual multi-parent tree in which a node maintains multiple parents whenever possible. A mobile node can still retain its upstream path to a gateway even though it loses connectivity to one of its parents. The new scheme is evaluated against the tree-based method and the other traditional methods - proactive, reactive, and hybrid by resorting to simulation. The result shows that the new method outperforms the other ones and also is very robust against the change of topology.

Traffic analysis based only on IP address is a new research area where traffic anomalies can be detected by studying clusters of IP addresses extracted from traveling packets. Such analysis is normally spatial and needs IP addresses to be put in a multi-dimensional map. This paper proposes a novel method that converts such maps to 2-dimensional graphical form and applies video compression techniques to create MPEG-2 VBR movies where frames are individual snapshots of IP space in time. The paper proves that this combination is suitable for traffic monitoring and detection of DDOS attacks as well as large-scale traffic anomalies caused by social phenomena.

As the speed of the Internet getting higher and accommodating a broader range of applications’ traffic, it becomes more difficult to monitor, analyze and manage the network traffic. To realize automatic network management of high-speed networks, we have developed two systems. One is a high-speed per-flow basis traffic analyzer using aggregated flow mining (AFM) that works with links of 10Gbps or higher. The other one is a network management system (NMS) using NETCONF as configuration protocols between NMS and network elements. For automatic network management, it is important that the NMS has flexibility to control a wide variety of network elements and also capabilities so that it can collaborate with flow collectors that capture and analyze network traffic data flows. To meet these requirements, a new application programming interface (API) that enables an NMS to control network elements, which include flow collectors, was developed.

High speed real-time precise traffic monitoring and control has gained significant interests by researchers in this field recently. This is mainly due to the fact that precise traffic measurement and analysis in a high-speed IP network environment is not a simple task. Let alone, control of such traffic in real-time is another big challenge. This paper addresses such complicated issues and proposes a novel solution which can precisely measure traffic in high-speed IP networks, classify them per application, create detailed flow-aware traffic information, and control per application basis. It includes motivation, architecture, and mechanisms. We have embedded capabilities of lossless packet capturing, deep packet inspection, and flow generation into hardware level. We describe major features, design concepts, implementation, and performance evaluation result.

Future Internet services will have vastly different requirements than the current Internet. Manageability, which has been largely ignored, will have the dual role of controlling capital and operational expenditures as well as enabling agile reorganization and reconfiguration of network services and resources according to changing business needs, user demands, and environmental conditions. Autonomic systems have the potential to meet these needs, but important architectural extensions are required. This paper examines the core building blocks of an autonomic system, and compares our approach to existing approaches with respect to Future Internet networks and networked applications. A special emphasis is placed on business driven services.

As large-scale computational applications in various scientific domains have been utilized over many integrated sets of grid computing resources, the difficulty of their execution management and control has increased. It is beneficial to refer job history from many application executions, in order to identify application’s characteristics and to decide grid resource selection policies meaningfully. In this paper, we apply a statistical technique, Plackett-Burman design with fold-over, for analyzing grid environments and execution history of applications. It identifies main factors in grid environments and applications, ranks based on how much they affect. Especially, the effective factors could be used for future resource selection. Through this process, application is performed on the selected resource and the result is added to job history. We analyzed job history from an aerospace research grid system. The effective key factors were identified and applied to resource selection policy.

Decentralized architectures have been proposed using functional hierarchies of several middle-level managers with delegation of management activities. However, no management applications have been implemented and widely used that could sanction this approach for real use. Also, current frameworks or mechanisms in network management do not directly address automation. More efficient network management systems with higher levels of availability and automation are needed. In this paper we propose a design and specify an automated and distributed network services monitoring system for Internet services that should be capable to effectively gather and calculate relevant operational parameters that will be used to determine the availability level of a network or application service. Based on this availability level, the system recommends or automatically triggers a service reconfiguration or a total or partial network service replication.

The increasing complexity, heterogeneity and unpredictability of networks make the task of managing these systems highly complex. The autonomic computing paradigm brings innovative solutions to the network management area with new adaptable and “clever” solutions which should consider a heterogeneous functionality in a wide variety of fields. One of the challenges involved in proposing autonomic solutions for QoS management consists of dealing with the inherent complexity and proposing solutions with feasible execution time. In brief, the autonomic solution effective response time should be fast enough so that it could be applied before any new important network state change. In this paper, a framework that uses self-partitioning methods is considered as the basis for evaluating a solution to the problem of dynamic LSPs setup allocation in a general MPLS network topology focusing on keeping a low complexity solution and aiming at achieving the best possible problem solution identification response time.

In this paper, we focus on the scheme for the route optimization in 6LoWPAN based MANEMO environments. If 6LoWPAN mobile routers for supporting NEMO protocol are organized by nested NEMO, this nesting of 6LoWPAN mobile router makes the extremely un-optimal route between 6LoWPAN nodes and its correspondent node. This is so, because all of the packets should be forwarded through the bi-directional tunnel which is established between 6LoWPAN mobile router and its home agent. Therefore, the more the number of nested levels, the packet route will become increasingly complex and it causes more end-to-end packet delay. This problem can be handled efficiently by applying MANEMO, which provides integration of MANET and NEMO protocols. With the application of MANEMO in 6LoWPAN, we can avoid the nested NEMO since MANET consisting of 6LoWPAN mobile routers can directly communicate with each other. In this paper, we propose an interoperable architecture between MANEMO and 6LoWPAN to solve the un-optimal route problem of the nested NEMO. With proposed scheme, we can provide the route optimization to communicate between 6LoWPAN node and correspondent node. Furthermore, we can also reduce the tunneling overhead and the end-to-end packet delay.

Applications in wireless sensor networks (WSNs) experience the routing hole problem. That is, the current node cannot forward to the destination, although it is the closest node, but not a neighbor of the destination. Accordingly, the packets from the source cannot be delivered to the destination. Jiang

et al.

recently proposed a SLGF approach to address this problem. However, SLGF still has long routing paths, since it uses the right-hand rule. In this paper, we describe Predictive Geographic greedy Forwarding, PGF. PGF uses information on the hole to build the virtual convex polygon, predict the routing path and choose the shorter path. PGF reduces the length and the number of hops of routing paths. Computer simulation shows our PGF scheme can reduce the average number of hops of routing paths by about 32% compared to Geographic greedy Forwarding, GF, and about 15% compared to SLGF.

In P2P file sharing systems, time dependent characteristics of query (query trends) for a file become much important to forecast the demand of the file in future. Prediction of future demand would be effective for the efficient use of the caching mechanism, however, the accurate prediction of query trend is difficult because patterns of query trends may differ significantly according to a nature of keyword used in the query. Identification of query pattern is one of important roles for accurate forecast of future query demand. In this paper, we propose a new method to classify measured query trends into some typical query patterns. We first measure query trend for each keyword in the most famous P2P file sharing system in Japan, and analyze the pattern of query trends by using clustering technique with Discrete Fourier Transform. We then apply our method to the measurement results and show that most of keywords can be categorized into one of four typical trend patterns.

So far, numerous wireless sensor networks have been deployed indepedently and restrictly used for specific services as isolated islands. Recently it is considered to exploit the sensor networks already deployed by others or open its sensor networks for sharing the sensor data. In this paper, we introduce our empirical development of a P2P system for sensor information. We design a gateway node which includes a sink function for sensor nodes and plays a role of a peer node of the proposed P2P system. And we modify an open P2P framework of Pasty for adopting sensor, sensor network and sensor information. This P2P system is referred to as sensor P2P. To test the utility of our sensor P2P system, we deploy this system in KOREN (KOrea advanced Research and Education Network) and develop an application using which a user can search a sensor network with key words, find the position of the sensor network on the digital map and receives sensor data from the sensor network.

SDP (Service Delivery Platform) is a recommended system platform for NGN (Next Generation Network) that is expected to resolve two common system running problems: one is functional aspects such as high availability and providing effective maintenance methods, the other is cost aspects such as simplifying development method of a service. However, SDP is still on the way to be standardized, and its architecture has two problems: the congestion of service requests and flexibility of enabler, a service component of SDP. This paper explains how to build a SDP by adopting Distributed Data Driven Architecture and how our system resolves the problems by evaluating the prototype.

Recently, with the progress of research on accurate traffic classification (TC), the major obstacle to achieving accurate TC is the lack of an efficient ground truth (GT) generation method. A firm GT is important for exploring the underlying characteristics of network traffic, building the traffic model, and verifying the classification result, etc. However, current existing GT generation methods can only be made manually or with additional high-cost DPI (deep packet inspection) devices. They are neither too complicated nor too expensive for research community. In response to this problem, we present LCGT, a low-cost continuous GT generation method for TC. Based on LCGT, we propose a novel updateable TC system, which can always reflect the features of up-to-date traffic. While we have found LCGT to be very useful in our own research, we seek to initiate a broader discussion to guide the refinement of the tools. LCGT is located on: http://code.google.com/p/traclassy

Femtocell is an emerging technology for expanding cell coverage and increasing data rate, and its users deploy in their own premises by themselves. Therefore, femto base stations cannot go through manual cell planning procedure as the mobile communication base stations do. Femto base station sets its parameters, such as transmit power or pilot power, considering the surrounding radio environment. Due to its automated cell planning and parameter setting, leakage of the power to the outside of a house can occur and lead to highly increased number of unwanted handover events of macrocell users, which will finally lead to higher call drop probability. In this paper, we propose a coverage self-optimizing scheme to decrease the call drop probability in a real residential scenario. Our proposed scheme prevents unwanted handovers and comprehensive simulation results show that it improves performance of network in terms of handover and call drop probability.

Unassumed teletraffic patterns, such as those caused by extra-high bit-rate mobile user traffic that is actively moving in a network, will become common on telecommunication networks in the 4G era. Unexpectedness and unevenness of their distribution will make it difficult to use “fundamental traffic,” which is the conventional concept of reference traffic used in Japan, based on the E.500 ITU-T series, for network resource dimensioning. For 4G, new radio access technologies are being intensively developed, but the research on traffic engineering is still insufficient. In this paper, a new modeling and magnification factor for reference traffic to handle such cases is proposed. It is called “redundancy under general traffic in a closed network.” Its calculation method approximated by using a normal distribution is described, and its accuracy on various network topologies is studied by Monte Carlo simulations.

This paper describes development of KQIs (Key Quality Indicators) and a prototype of the KQIs monitoring system for WiBro (Wireless Broadband Internet) service provided by Korea Telecom. In this paper, we analyze WiBro service model based on user’s perspective. Particularly, we essentially deal with the Web browsing service experienced by users as an internet service by WiBro Service. In addition, we focus on data bearer service with a wireless feature since it is the foundation of the WiBro Service. In developing the KQIs and KPIs, we use a top-down analysis method with user’s perspective and a bottom-up analysis method to get the data sources to be measured. We categorize them to Accessibility, Retainability, Quality, Latency, Supportability, and Diagnosis as combined KQIs with user’s perspective. Through this service model analysis, we identify the KQIs and KPIs based on the user to manage the WiBro service quality. And we analyze the gap between the developed quality indicators and the measurement of them in KT and implement the prototype of monitoring system for them.

For a videoconferencing service provider, the infrastructure design in multi-SLA (Service Level Agreement) environments plays a pivotal role in the maximization of business profits. Traditional design methods usually concern costs exclusively but overlook financial losses. In this work, an optimal design methodology is proposed using Business-Driven IT Management (BDIM) concepts, whereby numbers of servers, routers and link bandwidth can be determined to minimize the sum of infrastructure costs and business losses. This method captures the linkage between infrastructure and business impacts by modeling availability, multi-SLA loads and transmission delay. A numerical example is discussed to demonstrate the value of the approach. A further conclusion is that the optimal design can be used for dynamic service provisioning.

IEEE 802.11 MAC protocol for medium access control in wireless

Local Area Networks

(LANs) is the

de facto

standard for wireless ad hoc networks, but it does not necessarily satisfy QoS requirement by users such as fairness among flows or throughput of flows. In this paper, we propose a new scheme aiming to solve per-flow fairness problem and achieves good throughput performance in IEEE 802.11 multi-hop ad hoc network.

We apply a cross-layer scheme, which works on the MAC and link layers. In the link layer, we examine each flow and choose suitable contention window for each output packet from the flow. The aim of the mechanism is achieving per-flow fairness. In our proposed scheme, the MAC layer of each station tries to evaluate network condition by itself then adjust channel access frequency to improve network utilization and ensure per-node fairness. Performance of our proposed scheme is examined on various multi-hop network topologies by using Network Simulator (NS-2).

While there are many algorithms for finding a node-protected pair of multicast trees in a graph, all of the existing algorithms suffer from two flaws: Firstly, existing algorithms either have a long running time or produce high-cost tree pairs (Time-Cost Trade-Off). Secondly, existing algorithms aim to produce a low-cost tree pair, but do not take delay constraints into account (Delay-Cost Trade-Off). We tackle these trade-offs by introducing an iterative algorithm, which finds a low-delay tree pair very quickly and then iteratively seeks lower-cost pairs. We present a sequential version of our algorithm; as well as an architecture for implementing it in a computing cluster, along with the corresponding master- and slave-algorithms.

It turns out that the success percentage of our algorithm drops as the

average node degree decreases

, and as the

share of multicast destination nodes increases

. Fortunately, in these cases performance of the existing algorithms improves, which means that our algorithm complements the existing algorithms. Two additional benefits or our algorithm are: (1) it can be used in multi-homing scenarios with almost no modifications, and (2) it can be used in both directed and undirected graphs.

It is critical to obtain accurate network information for network management and the improvement of network service quality. Network measurement is an efficient method to obtain such information. Now the network measurement models and algorithms have become a research hot spot; and the core problem is how to cut down the cost of device deployment and reduce the effects caused by measurement. In this paper, we discuss the problem of measure station selection and measure assignment in active IP network, and propose a greedy algorithm to select stations and a method based on link usage cost to assign measures. Simulation results show that our method is efficient in station selection and measure assignment.

In a large backbone network, it is important to detect shape traffic fluctuation for servicing robust network. However, there are too many interfaces to monitor the characteristics of traffic. First we collect volume traffic of boundary link. From the volume traffic, we make groups which have similar traffic patterns by hierarchical clustering algorithm. This result shows that most of traffic has similar patterns, but some traffic which is far from centroid has an anomaly traffic pattern. This paper gives a hint for network operators that which traffic has to be checked out.

We propose a two-stage Distributed Denial of Service (DDoS) defense system, which can protect a given subnet by serving existing flows and new flows with a different priority based on IP history information. Denial of Service (DoS) usually occurs when the resource of a network node or link is limited and the demand of the users for that resource exceeds the capacity. The objective of the proposed defense system is to provide continued service to existing flows even in the presence of DDoS attacks, and we attempt to achieve this goal by discriminating existing flows from new flows. The proposed scheme can protect existing connections effectively with a reduced memory size by reducing the monitored IP address set through sampling in the first stage and using Bloom filters. We evaluate the performance of the proposed scheme through simulation.

Pairwise key establishment provides an effective way to build secure communication links among sensor nodes using cryptographic techniques. Up till now, researchers have devised numerous schemes that employ diverse cryptographic or combinatoric methods in order to provide high security, high connectivity and low storage overheads on the sensors. In this paper, we present a new framework on pairwise key establishment. We show that it can encompass most of the major previous schemes. Furthermore, we analyze the performance of the previous schemes using the proposed framework. When 100% connectivity is provided, under the same storage overhead on the sensor nodes, Blundo scheme and Blum scheme provide the highest security against intelligent adversaries while YG-L scheme is the best against random adversaries. When connectivity is under 100%, for random adversaries, location-aware schemes provide better security than non-location based schemes whereas for intelligent adversaries, all location based schemes’ security is less than that of other schemes.

In this paper, we investigate the major limitations of PFMIPv6, and explaine detailed lower layer procedures, which may significantly affect the handover performance. We propose a solution to reduce the overall channel scanning time by using IEEE 802.21 Media Independent Handover (MIH) services. MIH service is also used for efficient handover triggering and event notifications. In order to minimize the network attachment delay, we propose a fast re-association scheme for Mobile Node (MN). An efficient management of transient Binding Cache Entry (BCE) allows to eliminate out-of-order packet delivery and reduces the end-to-end delay at handover. Through the performance evaluations on OPNET network simulator, we validate that the proposed scheme provides better performance compared to PFMIPv6 and PMIPv6.

The WiMAX network has been proposed as an alternative technology to provide wireless network service. This paper focuses on WiMAX system forecasting in Mass Rapid Transit (MRT) environments and describes numerous models, including a user model, application model, economic model, subscription model, and evaluation model. We simulated a WiMAX network using these models to forecast the profitability of a broadband access system in an MRT environment.

Flooding is an indispensable operation for providing control or routing functionalities to wireless ad hoc networks. The traditional flooding scheme generates excessive packet retransmissions, resource contention, and collisions since every node forwards the packet at least once. Recently, several flooding schemes have been proposed to avoid these problems; however, these flooding schemes still have unnecessary forwarding nodes. In this paper, we present an efficient flooding scheme to minimize the number of forwarding nodes, based on a triangular tiling algorithm. Using location information of 1-hop neighbor nodes, our proposed scheme selects the nodes which are located closest to the vertices of an equilateral triangle which is inscribed in the transmission coverage as forwarding nodes. The most significant feature of our proposed flooding scheme is that it does not require any extra communication overhead other than the exchange of 1-hop HELLO messages. Simulation results show that our proposed scheme is so efficient that it has the capability to reduce the number of forwarding nodes such that it approaches the lower bound, hence, it alleviates contention and collisions in networks.

This paper focuses on the performance of the hybrid multiple access of CSMA/CA and TDMA, namely

CSMA/CA-TDMA

, in the 802.15.3c WPAN. A contribution of this paper is to provide an analytical model to study the system throughput of CSMA/CA-TDMA. A key property of the 802.15.3c WPAN is the directional communication due to the directivity of the mmWave radio. Another contribution is to analyze the system throughput for directional communication based on CSMA/CA-TDMA in the 802.15.3c WPAN. Numerical results show that the large number of the directions supported by the PNC could be a high overhead in the network as well as CSMA/CA-TDMA has higher system performance rather than CSMA/CA in case of happening high collisions.

In recent years many Internet video platforms, such as YouTube and MySpaceTV, are developed for users to share their videos with others. However, they are unable to do that wirelessly in a real-time fashion due to the insufficient network bandwidth or transmission quality. Under such context, the IEEE 802.16 standards have been proposed for high-speed communications. It enables video streaming in real time for mobile users. In this paper, we propose an architecture for mobile users to perform the upstreaming of their videos. The users can upstream their real-time videos through their mobile devices and wireless network technology. Due to the various network conditions and video quality, we propose the multiple profiles upstream function. We provide adaptive forward error correction codes, automatic repeat request, and unequal error protection for selection base on the hardware capability and the network states to ensure the quality of service. Finally, we use NS-2 as simulation tool to verify our algorithm.

Workflow technology is gaining major influence in many application domains. Especially, with the progress of the ubiquitous computing technology, a context-aware workflow has received considerable attention as a new workflow approach for a ubiquitous computing environment. This paper discusses security considerations for context-aware workflow systems and presents an architecture of a context-aware workflow authorization management (CAWAM) system. The CAWAM system offers management and enforcement of an authorization policy for context-aware workflow systems, and provides security-related context management functions. The CAWAM system utilizes the GCRBAC model for an access control service. In addition, the system supports a web-based policy management user interface.

Remarkable concerns have been made in recent years towards detecting the network traffic anomalies in order to protect our networks from the persistent threats of DDos and unknown attacks. As a pre-process for many state-of-the-art attack detection technologies, baseline traffic modeling is a prerequisite step to discriminate anomalous flow from normal traffic. In this paper, we analyze the traffic from various network transit points on ISP backbone network and present a baseline traffic model using simple linear regression for the imported NetFlow data; bits per second and flows per second. Our preliminary explorations indicate that the proposed modeling is very effective to recognize anomalous traffic on the real networks.

The Internet is comprised of a lot of interconnected networks communicating reachability information using BGP. Due to the design based on trust between networks, IP prefix hijacking can occurs, which is caused by wrong routing information. This results in a serious security threat in the Internet routing system. In this paper, we present an effective and practical approach for detecting IP prefix hijacking without major change to the current routing infrastructure. To detect IP prefix hijacking event, we are monitoring routing update messages that show wrong announcement of IP prefix origin. When a suspicious BGP update that causes MOAS conflict is received, the detection system starts idle scan for IP ID probing so that distinguish IP prefix hijacking event from legitimate routing update.

Wireless mesh network can increase service coverage by low-cost multiple-paths between a source and a destination. But because of the wireless nature, wireless mesh network is vulnerable to diversified threats. Especially attacks by malicious nodes can decrease the performance or ravage the network. Many protocols, based on Public Key Infrastructure (PKI), have been proposed to ensure security however; these protocols cannot efficiently prevent the cases of compromised nodes. In this paper, we propose a mesh router authentication scheme to solve this problem of existing protocols. Although our scheme increases the end-to-end delay, the proposed mesh router authentication scheme can guarantee secure wireless mesh network communication from malicious nodes.

In this paper, we present the personalization service in the IP Multimedia Subsystem (IMS) networks. It is the customized service that the service provider serves the optimal content on a suitable user’s situation within the various services. To serve that, the service provider has to develop the various types based on the analysis of user’s profiles and usage patterns that are recorded on the server. We have implemented the IMS infrastructure and simulated the personalization service on that.

The IPTV subscription rate has increased steadily since the introduction of IPTV Video on Demand (VoD) services. We have developed a model to determine the optimum deployment strategy for IPTV delivery network from the IPTV service providers’ perspective. The analysis technique in this paper helps us determine the best deployment scenarios to support a certain number of customers within the tolerant boundary of Quality of Experience (QoE) measures. We define important QoE measures. The QoE will help service providers make deployment decisions including the number of servers, distance of servers from a community, and desirable access network bandwidth capacity.

Wireless Sensor Networks (WSNs) are becoming increasingly important because of their reduced cost and a range of real world applications. IP connectivity to WSNs has enabled ubiquity of devices. 6LoWPAN networks are the realization of these IP based Ubiquitous Sensor Networks (IP-USNs). Management of such low power and constrained networks is a crucial problem. Remote configuration is an important management aspect where the devices are configured on runtime. In this paper we propose a remote configuration mechanism for IP-USNs.

Recently, a distributed hash table (DHT) has been used to construct peer-to-peer (P2P) overlay networks. DHT has high scalability for the number of peers, and peers can efficiently retrieve contents from the overlay network. Since DHT algorithms are used to construct symmetric network models, the communication cost of maintaining the routing table is low for peers that have a large computing or network resource and vice versa. We propose an asymmetric DHT network model that can be used to allocate appropriate jobs to a peer according to its performance.

A wireless sensor network consists of one or more hubs and lots of sensors. Sensors have capability of sensing, wireless communication and data processing. Therefore, how to extend the network lifetime is an important issue. In this paper, we propose a routing protocol which uses the water flow idea and allocates the loading based on the lowest energy in the paths. Our simulation result shows that the approach can extend the lifetime efficiently.

In next generation networks (NGNs), not only bearer quality management but also quality of experience (QoE) management is needed. One means of QoE monitoring is IETF RFC3611 RTCP XR which is a protocol for reporting the quality information measured at VoIP terminals. In our previous study, we propose a QoE monitoring method of VoIP using the XR. However, XR is not a fully mature technology, and some report parameters are vaguely defined to implement on a VoIP terminal. We focus on the XR parameters of network factors, loss rate, round trip delay, and jitter. We clarified the applicability to QoE monitoring of these XR parameters based on experimental results.

With the development of information and communication technologies, network convergence is inevitable trend. Because there are many heterogeneous networks in our daily lives, the heterogeneous network platform should provide the universal interfaces, regardless of the diversity of heterogeneous networks. A service abstract and integration method is proposed with corresponding interfaces in the paper. According to the application requirements, the platform can gain series of common service capability components from bottom heterogeneous networks by the abstract method. These service capabilities can be encapsulated to provide open interfaces with web service. The common services are also integrated to support new services or applications by the integration method. An illustration shows that the method is feasible on the platform to some extent.

High security and reliability is the essential design principle of the Olympic Games Network. This paper depicts the organization and its functionality of security and reliability design in 29

th

Olympic Games Network, such as architecture, 2-level DMZ, A/B systems, IP encoding and routing/switching. In addition, it describes the network optimization to meet the special requirements of Beijing MSTP MAN. In this paper, some experience of realizing a high security and reliability network is provided for reference.

The structures and systems of network and communication are independently constructed with existing based-IT service and 3G services without considering common functions between them. Consequently, the study of standardized Service Delivery Platform (SDP) structure and its related interfaces are needed to provide the methodology of existing or new services in an efficient way. Therefore, in this paper, we suggest the structure of common service enablers (i.e., PoC, Presence) for the SDP and show the way of interaction between them. Finally, we will describe an implementation of the components of the SDP using them.

Access control list (ACL) is one of the most important things in computer network security. While cheap router or PC processes ACL by software, network equipment such as Layer 2 or 3 switch processes ACL by hardware because there is a speed limit in software process ability. The hardware process of ACL can handle high speed network packet, however, this capability limits ACL configuration such as the limit of the number of rules in ACL. This paper proposes the software that decreases the number of rules in ACL to satisfy the limit of hardware. This paper also evaluates this software by experiment in which this software is applied to practical ACL.

As a key technology to reduce DNS resolution time, DNS performance optimization becomes a heated issue in the field of research. This paper proposes a novel DNS accelerator which based on the invalid TTL renewal policy to attain the quicker query speed. Compared with traditional server of DNS, the accelerator of DNS has much more excellent function at cache hit-rate, network traffic, CPU load and query-response time by the performance test to the concrete website. The new DNS accelerator has a magnificent accelerating rate.

Today many services over the networks, e.g., IPTV(Internet Protocol TV), web-based services are introduced to extend the business area of telcos(telecommunication companies). Therefore fault localization technique should be enhanced to cover the application layer. In this paper, we propose the rule-based alarm correlation method with functional event separation. And we also suggest modeling strategy for service resources and functional dependencies to enable those techniques. The proposed service fault localization method enables end to end service fault localization including application layer with less complexity and we prove it by implementing the pilot system for representative fault cases of real IPTV services.

In this paper, what we did on modeling of fault propagation behavior in WDM mesh networks and creation of leader major alarm domain concept are introduced and utilized as a basis for the development of our collaborative WDM network fault isolation approach. This approach fully takes the individual advantages of our two developed WDM network fault isolation methods to handle different fault situations (single-and multi-fault situations).

The introduction of the voice service to WiBro and the commercialization of 4G services will lead not only to the supersession of the existing voice market by m-VoIP but also to a greatly expanded market through the introduction of various value added services. For the purposes of this study, a market survey of Koreans was carried out as part of a methodical study of the factors influencing m-VOIP acceptance. Based on the findings of the study, the implications for the promotion m-VoIP in Korea are presented as the result.

An efficient management method for the Optical Transport Network (OTN) and Synchronous Digital Hierarchy (SDH) integrated network is described. We propose layer boundary section by focusing on the connection terminal point function on the OTN layer and, a management method for a fully connected OTN/SDH network.

This paper proposes an effective file searching scheme named Group P2P to reduce the number of message transmission. In the Group P2P, peers distinguish Parent Peer from Child Peer. Also, we propose another scheme to manage Child Peers for reducing overhead in the group as joining and leaving.

Because of rapid improvement in information and network technologies, many kinds of network services are created. In this paper, the concept of a new service platform is presented. Services are organized by components, and replications of components are distributed to many computers. Thanks to these replications, users can continue services by using another component as a substitute in case of failure. It is necessary to ask another component to find a substitute when a component fails. However, depending on which component to ask, the original version of the proposed method has a possibility to find only low-performance components. It is caused by constructing overlay network only once and keeping it as it is. We propose a new dynamic reconstruction method for overlay networks. Simulation experiments show how proposed method improves performance of our framework.

One of the most important considerations in designing sensor nodes in a wireless sensor networks is to extend the network lifetime by minimizing an energy consumption with limited resources. In this paper, we propose an Energy-Efficient Cluster Head Election (EECHE) algorithm in sensor networks The proposed algorithm divides cluster area into two perpendicular diameters, and then elects cluster head by the density of member nodes and the distance from cluster head. Through the simulation experiments, we showed that our algorithm has improves the performance of cluster head election and provides more energy-efficient.

Most of today’s network topology discovery algorithms discover network topology in a best effort fashion. To facilitate distributed network topology discovery in case of multiple network management systems used for distributed management of large corporate networks, this paper introduces boundary awareness in network topology discovery and presents three practical heuristic boundary rules to help determine the boundary of the network to be managed. Implementations of these boundary rules are also presented.

Wireless body area networks are operated within 3m around a human body. The 400 MHz frequency band for the medical implanted communication (MICS) has already been used for other service and consists of 10 channels with 300 kHz bandwidth each. Although wireless BANs consider interference mitigation techniques (LBT and AFA), they are not able to guarantee a reliable transmission. In this paper, we suggest a new reservation mechanism for multi-channel management in wireless BANs. Our mechanism achieves performance enhancements and coexistence with conventional techniques. Simulation results also show that can be achieved efficient channel utilization.

Accurate bandwidth measurement is essential for network management, monitoring, and planning. Various active probing-based strategies and tools are have been developed for estimating available bandwidth. However, the test result of each tool could be different according to the strategies and tools even in the same network environment. The purpose of this paper is to give comprehensive information to users with interpretive comparison and performance test. The comparison and test with regard to measurement efficiency, and traffic load of probing packets. including IGI/PTR, pathload, pathChirp, spruce, and Iperf, are performed in dynamic network environments.

The IP Multimedia Subsystem (IMS) in ALL-IP based next generation communication environment can offer network/service providers various multimedia services (e.g., voice, audio, video and data etc). The IMS is worthy of notice in that it is possible to make wired/wireless convergence and quick service development. The IMS needs an efficient Session Initiation Protocol (SIP)-based routing among Call Session Control Functions (CSCF) in charge of call and session processing. In this paper, we propose a routing management among CSCFs using management technology.

The RFID tag sensor networks have been developed as the new infrastructure which might bring the next generation ubiquitous networking. However, the RFID network has difficulty of the effective mutual communication with another RFID network, because plural standards coexist for RFID tags. To solve this difficulty, the RNI Standard has been proposed as the network management method which enables the consolidation among the RFID tag standards. The RNI Standard originally proposed was unfortunately insufficient for the smooth communication. This study analyses the problems of the RNI Standard. And the Operational Platform based on the standard is newly proposed with the verification of it’s expandability and practicality. The proposed scheme introduces the RFID tag separation processing environment. The proposed management scheme would be useful for the coming applications utilizing the plural RFID tag standards.

A web service is a software system designed to support interoperable machine-to-machine interaction over a network. Recently it is in the limelight being used for implementing Service Oriented Architecture (SOA). Traditionally, the web service for SOA is provisioned based on Simple Object Access Protocol (SOAP). In the advent of web 2.0, Representational State Transfer (REST) which focused on using the Web as it is by following its basic principles is come into being. As REST is becoming more popular, the design paradigm melted in REST makes Resource Oriented Architecture (ROA) an alternative or a complement to SOA. Telco has traditionally heavy transaction systems and network control systems are managed in a closed manner. So it is not easy to provide web services. In this paper, we propose a ROA-based web service provisioning methodology and a platform architecture for Telco. We also explain the implementation of the ROA-based web service platform in KT.

Recently, Botnet has been used to launch spam-mail, key-logging, and DDoS attacks. Botnet is a network of bots which are controlled by attacker. A lot of detection mechanisms have been proposed to detect Botnet on wired network. However, in IP based sensor network environment, there is no detection mechanism for Botnet attacks. In this paper, we analyze the threat of Botnet on 6LoWPAN and propose a mechanism to detect Botnet on 6LoWPAN.

In a mobile database environment, multiple mobile hosts may update the data items simultaneously irrespective of their physical locations. This may result in inconsistency of data items. Several Concurrency Control techniques have been proposed to eliminate the inconsistency of data items. Timeout based strategies are proposed in the literature to reduce the starvation problem in mobile environments with reduced rollbacks. However in each attempt the time of execution of the transaction is unnecessarily wasted though the timer value is known. In this paper we propose a strategy which executes a transaction only when the sufficient time is available for execution or the remaining time of execution is comparatively less. Experimental results show better throughput, and less waiting time for individual transactions.

This paper proposes an efficient message switch scheme on the vehicular telematics network, especially for the intersection area where routing decision may be complex due to severe traffic concentration. Each switch node opens an external interface to exchange messages with vehicles proceeding to the intersection from the pre-assigned branch as well as switches the received messages via the internal interfaces, accessing two shared channels according to slot-based MAC. Within each synchronized slot, channel probing and switching can efficiently deal with channel errors. The simulation result shows that the proposed scheme improves the delivery ratio by up to 13 % for the channel error rate range as well as up to 8.1 % for the given network load distribution.

The one hop relay selection problem is to find a node that can relay traffic from a source to a destination. The NAT traversal scheme in Skype VoIP networks is such an example. To find the optimal relay node requires a large amount of measurement traffic. Thus, a more scalable way to find a

good

relay node is crucial for the success of relaying. In this paper, we investigate the applicability of network distance based Euclidean coordinates for the one hop relay selection problem. Through a number of experiments with real measurement data sets, we show that the Euclidean coordinate system achieves close to the optimal performance in terms of delay.

This article presents an architecture of all-IP Based Future Heterogeneous Mobile Communication System (FHMCS). In this architecture Mobile Virtual Network Operator (MVNO) network has been proposed as an integral part of FHMCS that will facilitate the Mobile Station/User Equipment (MS/UE) in Network Discovery. The Network Discovery is achieved by using Mobile Network Information Repository (MNIR), embedded at the MVNO site. The network discovery will help reduce handoff latency, decreasing the probability of packet loss and handoff failures. In this article the population and updation of MNIR is presented. The network information will only be available to legitimate users of all Mobile Network Operators having a single Service Level Agreement (SLA) with the MVNO.

The analytical model proposed in the paper can be directly applied for modeling and dimensioning of the Iub interface in the UMTS network servicing the mixture of the Release 99 and HSDPA traffic streams. The presented model can be used for the blocking probability and the throughput determination for particular traffic classes carried by the Iub interface. The proposed scheme can be applicable for a cost-effective radio resource management in 3G mobile networks and can be easily applied to network capacity calculations.

Based on the Delayed ACK mechanism in TCP protocol, a new method is proposed to estimate the packet loss based on the variation of the rate between the bidirectional TCP packet numbers. This method made it possible to estimate the TCP packet loss based on the export of Netflow quickly.

We propose a QoS based migration system for virtual machines in data center environments. In order for our QoS based migration scheme to ensure QoS requirements for virtual machines, it estimates the QoS during migrations for each virtual machine, and selects the virtual machine that is most likely not to violate its QoS requirement. Moreover, it improves the overall system utilization by choosing the destination server for migration to balance resource usages.