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Ubiquitous Sensor Networks (USN) environment is composed of dense nodes of Ad-Hoc network structure which has small size node, low power and low calculation ability. Sensor nodes have constraints in operation which small size and distribution features so that they should be operated using low power. In this paper we propose a grid computing scheme to solve limited energy problems which can maintain the energy consumption as a same level though measuring remain energy with analyzing energy consumption of nodes. We confirm the improvement of survival time of entire nodes and less variation of topology in case of our proposed scheme through simulation. [ABSTRACT FROM AUTHOR]

Wireless communication technology has been introduced in the field of Intelligent Transportation Systems (ITS) in the past decades, and its applicability has been widely expending. Feasibility of the IR-DSRC based vehicle detection systems in measuring vehicle speed was tested as a possible alternative of the conventional inductive loop based systems requiring high construction and maintenance cost. It was found from the field test that the speed data from the IR-DSRC detection systems were statistically identical to the ones from the loop based systems at 95% confidence level. [ABSTRACT FROM AUTHOR]

It is widely accepted that the coverage with high user densities can only be achieved with small cell such as Micro / Pico-cell. The smaller cell size causes frequent handoffs between cells and a decrease in the permissible handoff processing delay. This may result in the handoff failure, in addition to the loss of some packets during the handoff. In this paper we propose new handoff control scheme in the next generation mobile communications, in which the handoff setup process is done in advance before a handoff request by predicting the handoff cell based on mobile terminal’s current position and moving direction. [ABSTRACT FROM AUTHOR]

It is very crucial in the field of security control to acquire the capability of promptly coping with various threatening elements in cyber world such as vicious worms, virus and hackings that cause enormous damage and loss across the nation within a rather short term period like the large scale network paralyzed by vicious traffic, disturbance of electronic commerce, etc. As such, it can be the fundamental measure on these sorts of threats to establish the new method of detecting the similar threats as well as to reinforce the user’s recognition of security. The purpose of this study is to analyze the problems in the existing IDS and TMS, which are monolithic in terms of detection method, and further to suggest the improved detection method and HOIDS system which is recently introduced and in test operation. [ABSTRACT FROM AUTHOR]

Flash memory is used at high speed as storage of personal information utilities, ubiquitous computing environments, mobile phones, electronic goods, etc. This is because flash memory has the characteristics of low electronic power, non-volatile storage, high performance, physical stability, portability, and so on. However, differently from hard disks, it has a weak point that overwrites on already written block of flash memory is impossible to be done. In order to make it possible, an erase operation on the written block should be performed before the overwrite, which lowers the performance of flash memory highly. In order to solve this problem, the flash memory controller maintains a system software module called the flash translation layer(FTL). In this paper, we propose an enhanced log block buffer FTL scheme, FAST(Fully Associative Sector Translation), which improves the page usability of each log block by fully associating sectors to be written by overwrites to the entire log blocks. We also show that our FAST scheme outperforms the previous log block buffer scheme. Keywords: Operating Systems, Flash memory, FTL, Address translation, Associative mapping. [ABSTRACT FROM AUTHOR]

As process technology scales down, power wall starts to hinder improvements in processor performance. Performance optimization has to proceed under a power constraint. The co-optimization requires exploration into a huge design space containing both performance and power factors, whose size is over costly for extensive traditional simulations. This paper describes a unified model covering both performance and power. The model consists of workload parameters, architectural parameters plus corresponding power parameters with a good degree of accuracy compared with physical processors and simulators. We apply the model to the problem of co-optimizing the power and performance. Concrete insights into the tradeoffs of designs for performance and power are obtained in the process of co-optimization. [ABSTRACT FROM AUTHOR]

Until a recent date all telephony connections are set up via circuit switching. Advances in networking technology have made it possible for the Internet evolves into a Broadband convergence Network (BcN) and provides various services including Internet Protocol (IP) telephony over high-speed IP networks. Voice-over-IP (VoIP) uses packetized transmission of speech over the Internet. In order for the Internet to realize a profit as traditional Public Switched Telephone Network (PSTN), it must provide high quality VoIP services. The VoIP metrics report block of Real-Time Transport Protocol Control Protocol Extended Reports (RTCP XR) can be applied to any one-to-one or one-to-many voice application for which the use of RTP and RTCP is specified. However, RTCP XR only defines packet type to convey information that supplements the six statistics that are contained in the report blocks used by RTCP’s Sender Report (SR) and Receiver Report (RR) packets. Our objective in this paper is to describes a practical measuring framework for end-to-end QoS of packet switched voice in an IP environment including Packet Loss Concealment (PLC) techniques. It includes concepts as well as step-by-step procedures for setting up components, creating session, measuring packetized voice streams over IP networks. [ABSTRACT FROM AUTHOR]

Detecting network address translation is helpful for network administrators to enhance the network security. Current network address translation detection approaches can not work effectively in all scenarios. In this paper, a new detection scheme ImNatDet utilizing instant messaging information is presented, a case study based on characters of MSN Messenger is analyzed, and related security issues are discussed. This paper also indicates that characters of instant messaging applications can be used to detect users’ privacy information. [ABSTRACT FROM AUTHOR]

Multimedia stream standards evolve rapidly as stream applications prosper in embedded systems. A key component of standards, discrete cosine transform is being replaced by SA-DCT, whose complexity results in a large design space. The paper describes a UML 2.0 based design approach to quick evaluation of SA-DCT implementations containing both hardware and software, which are hard to describe and verify in C, Verilog and VHDL. Using the approach, we manage to study the partitioning, reconfigurability as well as performance and hardware cost. The design specifications in UML can be translated into SystemC models consisting of simulators and synthesizable code under proper style constraints. The paper demonstrates the feasibility of quick specifications, verification, evaluation and generation of embedded system designs. [ABSTRACT FROM AUTHOR]

The hardware-software automated partitioning of a RTOS in the SoC (SoC-RTOS partitioning) is a crucial step in the hardware-software co-design of SoC. First, a new model for SoC-RTOS partitioning is introduced in this paper, which can help in understanding the essence of the SoC-RTOS partitioning. Second, a discrete Hopfield neural network approach for implementing the SoC-RTOS partitioning is proposed, where a novel energy function, operating equation and coefficients of the neural network are redefined. Third, simulations are carried out with comparisons to the genetic algorithm and ant algorithm in the performance and search time used. Experimental results demonstrate the feasibility and effectiveness of the proposed method. Keywords: Hardware-software partitioning, RTOS, SoC, Hopfield neural network. [ABSTRACT FROM AUTHOR]

At the transition from a tangent section to a curved section, it is possible for a following vehicle with adaptive cruise control in car-following mode to lose track of the lead vehicle. This occurs because the lead vehicle enters the curve and its path diverges from the axis of the following vehicle, yet the following vehicle does not yet have lateral acceleration information that would induce its range sensor to bend according to the curvature of its own path. This is a temporary situation, but one that could have an impact on cruise control safety and appropriate algorithms. In this paper, the conditions of time and distance that produce this circumstance are derived. Examples are given using typical values of roadway and vehicle parameters. Finally, some conclusions regarding possible solutions are offered. [ABSTRACT FROM AUTHOR]

We propose a new authentication scheme of binding update protocol, which its Correspondent Node (CN) issues a ticket to Mobile Node (MN) when MN first executes the Binding Update (BU). This ticket assist that it is able to do efficiently the BU whenever MN requires the BU for the future. The proposed protocol need not be repeated equal BU course whenever the MN moves to foreign link or network, and is able to be executed in environment of not operating the Home Agent (HA), and also easies scalability. [ABSTRACT FROM AUTHOR]

We propose analytic model of the delay of the Slotted ALOHA protocol with Binary Exponential Backoff (BEB) as a collision resolution algorithm in mobile multimedia networks. We verify the proposed analytic model using the computer simulation. In numerical results, our proposed method show correct analytic model and has better performance results than previous methods in mobile multimedia networks. [ABSTRACT FROM AUTHOR]

Java Card technology provides a secure, vendor-independent, ubiquitous Java platform for smart cards and other memory constrained devices such as SIM technology. It is also an open standard in SIM and UIM technology for 3G environment. However, the major point of criticism with regard to Java for smart cards and SIM cards is its low execution speed, aside from its memory demands. We found out that the most long-time work during the execution is to write data to non-volatile memory such as Flash memory. In this paper, we make a suggestion to improve the execution speed by buffering effectively Java Card Objects in order to reduce the number of flush() method. With our approach, the total number of flash writing and the execution speed of applications reduced by about 50% and 38% separately. [ABSTRACT FROM AUTHOR]

This paper propose to see how the center based car navigation systems are practical in terms of using real time traffic information and guiding the way with different media of both of the Turn by Turn and the digital map service. The systems have been applied to all the road networks in Korea but the traffic actuated car navigation systems are mainly applicable to the road networks in the Seoul, which has 40 km diameter, including satellite cities. As a result of this, the actual driving tests are conducted in that area. The tests are analyzed using two aspects. The first aspect is that the quality of the information using the car navigation systems can be acceptable to the customers in around 80 percentage of a statistical level. The other is if the user- friendly interface is relatively helpful to the customers while they are driving a car. The result shows that the route displayed on the TFT LCD helps the drivers to understand which way they have to take. [ABSTRACT FROM AUTHOR]

This paper proposes more various key generation algorithms than conventional encryption method, and more secure encryption method that does not keep each symmetric key of key generation algorithm in server. After implementing proposed system, we verify the system using various sizes of video data. We get the fact that proposed system can reduce the delay time of encryption and decryption at the replay of video data. [ABSTRACT FROM AUTHOR]

This paper presents a true ortho-image generation scheme in urban areas for web GIS application such as urban management system. Proposed scheme includes the solution of conventional problems in normal ortho-image generation. Especially, our approach is focused on the automation and consistency of ortho-image in complex urban areas. For this purpose, we generated additionally plotted DSM (Digital Surface Model), which includes roads, high-level roads, bridges, and tunnels, automatically detected occlusion pixels and restored occlusion areas using a self-developed algorithm, and performed mosaic process using road-based seamlines. Total 2,677 aerial color images were used to create the so called true ortho-image map for Seoul metropolitan city. It turned out that the proposed method could generate true ortho-image map for urban areas with high positional accuracy and good visual consistency. The generated ortho-image database is being successfully operated by Seoul Metropolitan Aerial Photography Management Systems on the web and urban management systems. [ABSTRACT FROM AUTHOR]

This paper presents a mobility prediction method for context-aware service in mobile networks. It aims to reduce the latency time to get the refreshed information appropriated to the current location of mobile users. The proposed method is to effectively limit the prefetched information into the most next location context. It makes use of the mobile reference count and the residence time that stands for the mobile user’s visiting characteristics in any cell area. Then it also considers the information usability in order to further predict the prefetching candidates. In the numerical results, the proposed method is less latency time than that of the previous schemes to prefetch information matched to user’s current location. [ABSTRACT FROM AUTHOR]

As the ever-increasing gap between the speed of processor and the speed of memory has become the cause of one of primary bottlenecks of computer systems, modern architecture systems use cache to solve this problem, whose utility heavily depends on program data locality. This paper introduces a platform independent data-layout optimization framework to improve program data locality. This framework uses a variable relation model based on variables’ reuse distance distribution to quantitate the relation of variables and accordingly assigns variables which are often accessed together in one group. At the same time this framework introduces a dynamic array regrouping method to group dynamic arrays assigned in a group. Experiments show that this data-layout optimization framework can effectively improve program data locality and program performance. [ABSTRACT FROM AUTHOR]

In this paper, we propose an identities(ID) based watermarking scheme for Java programs. In our scheme, the watermark is generated by participants’ identities, embedded via the watermarked opaque predicates, and verified using zero-knowledge proof. We also present a construction of a family of opaque predicates by Legendre symbol, which is resilient, cheap, and stealthy. The order of the watermark is encoded and embedded into the watermarked opaque predicates, and the watermarked opaque predicates are treated as threads of a Java program. Thus, the embedded watermark is dynamic and secure against all usual types of watermarks algorithms attacks and watermarks protocols attacks, and also secure against static and dynamic attacks. Keywords: Java programs, watermarked opaque predicates, ID, aggregate signature, watermarking scheme. [ABSTRACT FROM AUTHOR]

This paper birefly introduces a Chinese digital input method named as CKCDIM (CKC Digital Input Method) and then applies it to the Symbian OS as an example, and it also proposes a framework of input method which adopted the Client/Server architecture for the handheld computers. To improve the performance of CKCDIM, this paper puts forward a dynamic and self-study language model which based on a general language model and user language model, and proposes two indexes which are the average number of pressed-keys (ANPK) and the hit rate of first characters (HRFC) to measure the performance of the input method. Meanwhile, this paper brings forward a modified Church-Gale smoothing method to reduce the size of general language model to meet the need of mobile phone. At last, the experiments prove that the dynamic and self-study language model is a steady model and can improve the performance of CKCDIM. Keywords: Chinese Digital Input Method, Architecture of Input Method, Dynamic and Self-study Language Model, HRFC, ANPK. [ABSTRACT FROM AUTHOR]

Runtime data alignment has been paid attention recently since it can allocate data segment to processors dynamically according to applications’ requirement. One of the key optimizations of this problem is to schedule simultaneous communications to avoid contention and to minimize the overall communication costs. The NP-completeness of the problem has instigated researchers to propose different heuristic algorithms. In this paper, we present an algorithm independent technique for optimizing scheduling stability of different scheduling heuristics. The proposed technique introduces a new scheduling policy, Local Message Reduction (LMR), to obtain better communication schedule adaptive to different environments. o evaluate the performance of the proposed technique, we have implemented LMR along with two existing algorithms, the two-phase degree reduction and the list scheduling algorithms. The experimental results show that the proposed technique is effective in terms of scheduling stability, communication efficiency and easy to implement. [ABSTRACT FROM AUTHOR]

This paper presents the design of a high performance energy-aware whole-system emulator - SkyEye. Several optimization and novel energy estimation methods used in SkyEye are proposed. By using novel searching strategy for Translated Block (TB), SkyEye save the time to find proper translated block. SkyEye uses Basic Equal Length Unit (B-ELU) method, and dynamic binary translation to reduce the simulation and energy evaluation time. The performance model of B-ELU is built to get the best length of translated block. In addition, the simulator automatically detects the voltage/frequency variation, and adjusts the energy estimation model accordingly. Using these methods, SkyEye which simulates ARM CPU based hardware system achieves marvelous performance and energy-aware statistic capability in experiments. Keywords: Emulator, Dynamic Binary Translation, Embedded System, Energy Estimation. [ABSTRACT FROM AUTHOR]

Programmable vertex processing unit increases the programmability and enables customizations of transformation and lighting in the graphics pipeline. Furthermore, it offers various effects such as procedural vertex animation and deformation, which were impossible to handle in fixed vertex processing. Since it is hard to find a programmable graphics hardware for the embedded systems such as mobile phones, we’ve designed and implemented a programmable vertex processing unit based on the OpenGL ES 2.0 specification. In this paper, we explain the architecture, instruction format, implementation and test results of our vertex processing unit. [ABSTRACT FROM AUTHOR]

With the increasing complexity of the real-time embedded software, the power consumption is becoming a real challenge in the system designs. In this paper, for modelling the component-based embedded software, the interface automata is extended by adding time intervals on the actions and assigning energy consumption rates on the states. The extensional formalism is called energy interface automata. Then the system designs are modelled by energy interface automaton networks which consist of a set of energy interface automata synchronized by shared actions. Based on analyzing the integer state space of the energy interface automaton networks and its compatible reachiability graph, we develop two algorithms for the problem of the minimal energy consumption calculation and the maximal energy consumption verification respectively. Keywords: embedded software design, power-aware computing, component-based design, real-time system, model checking, interface automata. [ABSTRACT FROM AUTHOR]

A verifiably encrypted signature can convince the verifier that a given cipher-text is the encryption of a signature on a given message. It is often used as a building block to construct optimistic fair exchange. Recently, Gu et.al gave an ID-based verifiably encrypted signature scheme and claimed that their scheme was secure in random oracle model. Unfortunately, in this works, we show that their scheme is insecure. And we can mount to universal forgery attack in their model. In other words, any one is able to forge a verifiably encrypted signature on arbitrary message m. Subsequently, a novel verifiably encrypted signature scheme (VES) is proposed and the scheme is proven secure in random oracle model. Moreover, the size of verifiably encrypted signature in our scheme is shorter than that of Gu et.al’s signature. [ABSTRACT FROM AUTHOR]

The method of broadcast encryption has been applied to the transmission of digital information such as multimedia, software, and paid TV on the open network. In this broadcast encryption method, only previously authorized users can gain access to digital information. When broadcast message is transmitted, authorized users can first decode the session key using the previously given private key and get digital information using this session key. This way, users retrieve a message or a session key using the key transmitted by broadcasters. For their part, broadcasters need to generate and distribute keys. Broadcasters should also carry out efficient key renewal when users subscribe or unsubscribe. This paper introduces how to generate and distribute key efficiently and how key renewal works. The proposal uses two methods: (1) the server generates keys without the consent of users by anticipating users, and; (2) the server and users generate keys by mutual agreement. The advantage of the two proposed methods is that the receiver can decode broadcast message using a secret key. Even if the key is renewed later, the user can efficiently renew using only a single set of information. [ABSTRACT FROM AUTHOR]

Modern portable or embedded systems support more and more complex applications. These applications make embedded devices require not only low power-consumption, but also high computing performance. To enhance performance while hold energy constraints, some high-end embedded processors, therefore, adopt conventional features to exploit instruction-level parallelism and increase clock rates. The reorder buffer (ROB) and the register file are the two most critical components to implement these features. The cooperation of them, however, causes serious leakage power, especially for a large register file. In this paper, we propose a pure hardware approach to reduce the leakage power for the register file, such that more complex features (e.g., out-of-order execution, speculation execution, etc) can be applied to high-end embedded processors. In the proposed approach, we design a monitoring scheme in the pipeline datapath to identify the timing of powering up or powering down a register. Simulation results show that our approach saves at least 50% power consumption of the register file, with almost negligible performance lost. Keywords: register leakage power, dynamic voltage scaling (DVS), reorder buffer, high-end embedded processor. [ABSTRACT FROM AUTHOR]

A priority-driven scheduling algorithm is said to be start time (finish time) predictable if the start time (finish time) of jobs in the schedule where each job executes for its actual execution time is bounded by the start times (finish times) of jobs in the schedules where each job executes for its maximum/minimum execution time. In this paper, we study the predictability of a job-level dynamic priority algorithm, LLF (Least Laxity First), on multiprocessor real-time systems. We present a necessary and sufficient condition for a priority-driven algorithm to be start time (finish time) predictable. Then, in LLF scheduling, we show that both the start time and the finish time are predictable if the actual execution times cannot be known. However, solely the finish time is predictable if the actual execution times can be known. [ABSTRACT FROM AUTHOR]

An iterative modulo scheduling is very important for compilers targeting high performance multi-issue digital signal processors. This is because these processors are often severely limited by idle state functional units and thus the reduced idle units can have a positively significant impact on their performance. However, complex instructions, which are used in most recent DSPs such as mac, usually increase data dependence complexity, and such complex dependencies that exist in signal processing applications often restrict modulo scheduling freedom and therefore, become a limiting factor of the iterative modulo scheduler. In this work, we propose a technique that efficiently reselects instructions of an application loop code considering dependence complexity, which directly resolve the dependence constraint. That is specifically featured for accelerating software pipelining performance by minimizing length of intrinsic cyclic dependencies. To take advantage of this feature, few existing compilers support a loop unrolling based dependence relaxing technique, but only use them for some limited cases. This is mainly because the loop unrolling typically occurs an overhead of huge code size increment, and the iterative modulo scheduling with relaxed dependence techniques for general cases is an NP-hard problem that necessitates complex assignments of registers and functional units. Our technique uses a heuristic to efficiently handle this problem in pre-stage of iterative modulo scheduling without loop unrolling. Keywords: code generation and optimization, application specific embedded software design, software pipelining, dependence analysis, high performance DSPs. [ABSTRACT FROM AUTHOR]

Currently the Java programming language is popularly used in Internet-based systems, mobile and ubiquitous devices because of its portability and programability. However, inherently its performance is sometimes very limited due to interpretation overhead of class files by Java Virtual Machines (JVMs). In this paper, as one of the solutions to resolve the performance limitation, we present code generation and optimization techniques for a Java-to-C translator. Our compiler framework translates Java bytecode into C codes with preserving Java’s programming semantics, such as inheritance, method overloading, virtual method invocation, garbage collection, and so on. Moreover, our compiler translates for in Java into for in C instead of test and jump for better performance. Our runtime library fully supports Connected Limited Device Configuration (CLDC) 1.0 API’s. [ABSTRACT FROM AUTHOR]

Most vendors of digital signal processors (DSPs) support a Harvard architecture, which has two or more memory buses, one for program and one or more for data and allow the processor to access multiple words of data from memory in a single instruction cycle. We already addressed how to efficiently assign data to multi-memory banks in our previous work. This paper reports on our recent attempt to optimize run-time memory. The run-time environment for dual data memory banks (DDMBs) requires two run-time stacks to control activation records located in two memory banks corresponding to calling procedures. However, activation records of two memory banks for a procedure are able to have different size. As a consequence, dual run-time stacks can be unbalanced whenever a procedure is called. This unbalance between two memory banks causes that usage of one memory bank can exceed the extent of on-chip memory area although there is free area in the other memory bank. We attempt balancing dual run-time stacks to enhance efficiently utilization of on-chip memory in this paper. The experimental results have revealed that although our call chain balancing (CCB) algorithm is relatively quite simple, it still can utilize run-time memories efficiently; thus enabling our compiler to run extremely fast, yet minimizing the usage of run-time memory in the target code. Keywords: Run-time environment, DSP, dual data memory banks, compiler, and on-chip memory. [ABSTRACT FROM AUTHOR]

Even though its advantages such as non-volatility, fast write access time and solid-state shock resistance, NAND flash memory suffers from out-place-update, limited erase cycles, and page-based I/O operations. How to provide fast mounting and consistency of file system and data for flash memory file systems has become important research topics in recent years. In this paper, we design and propose a new flash memory file system called RFFS (Reliable Flash File System), which targets NAND flash memory based embedded systems that require fast mounting and fault tolerant file system. We have experimented on the performance of RFFS and the results showed that RFFS could improve the mounting time by 65%-76% compared with YAFFS. Also RFFS improved mounting time after sudden system faults by 89%-92% compared with JFFS2. [ABSTRACT FROM AUTHOR]

The new algorithmic technique which allow higher efficiency in the precise calculation of the reliability of an undirected graph with absolutely reliable nodes and unreliable edges is considered in this paper. As graph’s reliability we mean its probabilistic connectivity. The proposed technique is based on the reduction of the dimension of a calculated graph by considering its node’s cuts. Comprehensive computer simulation results show the advantages of the proposed algorithms, that the calculation time decreases significantly in comparison with existent methods. [ABSTRACT FROM AUTHOR]

In this paper, we study the web technologies that allow ubiquitous spaces to create dynamic web pages in accordance with user profiles. Especially, we explore the server-side scripting approach, the most popular technology for dynamic web pages. This approach mainly adopts the execute-while-parsing model, which suffers from the interpretation overhead. Recently, the compilethen- execute model was proposed to address the overhead. This paper compares and analyzes the two models, while performing benchmark test in Microsoft ASP and ASP.NET environment. The benchmark results show that, due to the high initialization overhead, the compile-then-execute model cannot substantially improve the execute-while-parsing model. Also, the best performance can be achieved through optimization rather than compiled execution. Based on the results of the benchmark test, we develop a speedup model, which estimates the maximum performance improvement achievable by the compile-then-execute model. [ABSTRACT FROM AUTHOR]

The lack of verifying source address in Internet makes it easy for attackers to spoof the source IP address. One of challenges of Internet has been recognized is building mechanisms in routers to verify the source address. This paper discusses Source Address Spoofing Prevention (SASP) mechanisms, presents a formal description on SASP network and SASP router, proposes a hierarchical SASP architecture, and presents some design principles of SASP mechanisms. Keywords: Source Address Spoofing, Source Address Validation, Network Security. [ABSTRACT FROM AUTHOR]

Due to the stateless nature of the internet, it is an intricate problem to determine the source of spoofed attacking packets. To handle this problem we utilize the IP traceback mechanism to know the actual source of an IP datagram. 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 difference exists between IPv4 and IPv6 Networks. Therefore, the mechanisms for tracing the origin of attacks in IPv6 networks have abundant differences from those of IPv4 networks. In this paper, we proposed an efficient Lightweight IPv6 traceback algorithm. We also discussed the problems related to previously proposed IPv4 traceback schemes and presented the Error Correction and Modified Path MTU calculation algorithm to make our scheme more practical.This work was supported by MIC and ITRC Project. Dr. CS Hong is the corresponding author. [ABSTRACT FROM AUTHOR]

In this paper, we propose multimedia service system, called C-iUMS (Context based intelligent Ubiquitous Multimedia Service), for smart and secure service based on context in intelligent ubiquitous home. The proposed system provides user centric multimedia service based on context including user location, user preference and device status information. In addition, the proposed system supports ubi-home super-distribution which contents can distribute safely and consume from the central intelligent and secure media center to the end terminal in intelligent ubi-home. Furthermore, we propose and apply a VTDiC algorithm for customized contents to multimedia players. Finally, a prototype of USN device is designed and implemented to realize intelligent Ubi-home supporting smart service. [ABSTRACT FROM AUTHOR]

The goal of our research is to provide an advanced programming environment for ubiquitous computing, which facilitates the development of secure and reliable ubiquitous software. The environment consists of a high-level ubiquitous programming framework, a run-time system enhanced with better context adaptation and security, and programming support tools. In this paper, we focus on a ubiquitous programming framework, which includes a high-level policy description language, a translator to Java and a runtime system. We first present a high-level policy description language for formally specifying context entity relation, as well as context-based access control and adaptation policies. We then describe how a specification in the policy description language can be translated into Java code which makes use of JCAF. [ABSTRACT FROM AUTHOR]

In this paper, we present FBAC (Flexible Bound Admission Control) algorithm using softness profile to reduce handover blocking probability over WLAN and WAAN (Wide Area Access Network). FBAC algorithm utilizes dynamic resource allocation scheme to decrease the blocking probability of vertical handover connections within the limited capacity of system. Based on FBAC algorithm, we derive the handover blocking probability as new traffic load and handover traffic load increase. In order to evaluate the performance, we compare FBAC algorithm against traditional non-bounded and fixed bound schemes. Numerical results show that the FBAC scheme improves handover blocking probability in ubiquitous environment. [ABSTRACT FROM AUTHOR]

Nowadays, computer network systems play an increasingly important role in our society. They have become the target of a wide array of malicious attacks that can turn into actual intrusions. This is the reason why computer security has become an essential concern for network administrators. Intrusions can wreak havoc on LANs. And the time and cost to repair the damage can grow to extreme proportions. Instead of using passive measures to fix and patch security holes, it is more effective to adopt proactive measures against intrusions. Recently, several IDS have been proposed and they are based on various technologies. However, these techniques, which have been used in many systems, are useful only for detecting the existing patterns of intrusion. It can not detect new patterns of intrusion. Therefore, it is necessary to develop a new technology of IDS that can find new patterns of intrusion. This paper investigates the asymmetric costs of false errors to enhance the detection systems performance. The proposed method utilizes a network model considering the cost ratio of false errors. Compared with false positive, this scheme accomplishes both security and system performance objectives. The results of our empirical experiment show that the network model provides high accuracy in detection. In addition, the simulation results show that effectiveness of probe detection can be enhanced by considering the costs of false errors. [ABSTRACT FROM AUTHOR]

In a ubiquitous computing environment, every service should have the characteristic of context-awareness and location information is an important factor to grasp a user’s context. Thus, location privacy is an major security issue of ubiquitous computing environment. Most research on location privacy is focused on protecting the location information itself. However, not only prohibiting acquirement of the sensitive information illegally but also forbidding abuse of the information obtained legally is important to protect user privacy. In order to satisfy this claim, we propose a new privacy-aware service protocol for a ubiquitous computing environment. The proposed protocol decouples the relation between a user’s identity and location. Moreover, it uses anonymous communication channel to hide the user’s service consume pattern. [ABSTRACT FROM AUTHOR]

A framework for the autonomous management of large-scale ubiquitous sensor networks called SNOWMAN (SeNsOr netWork MANagement) is proposed in this paper. In large-scale ubiquitous sensor networks, a huge number of sensor nodes are deployed over a wide area and long distances and multi-hop communication is required between nodes. So managing numerous ubiquitous sensor nodes directly is very complex and is not efficient. The management of large-scale ubiquitous sensor networks therefore must be autonomic with a minimum of human interference, and robust to changes in network states. The SNOWMAN is responsible for monitoring and controlling ubiquitous sensor networks based on policy-based management paradigm. It allows administrators to simplify and automate the management of ubiquitous sensor networks. It can also reduce the costs of managing sensor nodes and of the communication among them using a new hierarchical clustering algorithm. [ABSTRACT FROM AUTHOR]

Grid computing and pervasive computing have rapidly emerged and affirmed as paradigms for high performance computing and for user-friendly computing respectively. These two separate worlds, however, can now interact each other in such a way that both pervasive and grid computing communities can benefit from integrating the two paradigms into a whole. This conjunction is already taking place to yield the pervasive grid computing model, and the present paper is focused on this approach. Purposely, it describes an Access & Location service for pervasive grid applications which uses RFID and WiFi technologies to grant access and locate mobile objects within a pervasive environment. Since this service is compliant to the OGSA specifications, it can be easily integrated into classic grid environments, therefore enhancing them with pervasive capabilities. [ABSTRACT FROM AUTHOR]

The ability to recognize many tags simultaneously is crucial for many advanced RFID-based applications. The tag anti-collision algorithm of an RFID system, which arbitrates collisions on the air interface among tags in the same reading range of a reader, makes a great influence on the speed and the reliability in multiple tag recognition. This paper presents a new memoryless tag anti-collision algorithm, QT-CBP (Query Tree with Collision Bit Positioning), which is designed based on QT (Query Tree) algorithm. QT-CBP is likely to make more concise tree traversal than QT by extracting and making use of detailed information on a collision condition, such as the number of collision bits and their positions. Basically QT-CBP is an enhanced algorithm for readers running QT, so no change is required at tags. Simulation study shows that QT-CBP outperforms QT, especially on the condition where tags have similar tag IDs by having the same company or product ID prefixes. [ABSTRACT FROM AUTHOR]

Radio Frequency Identification (RFID) systems are increasingly becoming accepted for many EPC Network applications. However, RFID systems have some privacy problems. In this paper, a system for missing child location tracking in the EPC Network applications, is proposed. The proposed system improves security and privacy compared to existing applications, while also keeping in line with traditional procedures, commonly accepted by most industrial applications. The proposed MCLT (Missing Child Location Tracking) system can protect users’ privacy while providing location tracking of the RFID tag. Keywords: EPC Network, RFID system, application service, privacy, security, location tracking. [ABSTRACT FROM AUTHOR]

This paper proposes an efficient end-to-end QoS supporting mechanism in Next Generation Network (NGN) with heterogeneous QoS capability to support ubiquitous and distributed applications. To address this, there should be proper admission control mechanism and adaptive provisioning to sustain end-to-end QoS and maximize network utilization. Resource and Admission Control Subsystem of NGN has unique feature of centralized network resource control rather than other network control protocol system in IP network. By showing optimal flows in heterogeneous QoS capability network, NGN can support average delay of end-to-end which the applications could receive proper Quality of Service over network. Keywords: NGN, end-to-end QoS, resource admission and control, differential service. [ABSTRACT FROM AUTHOR]

This paper presents the design of the adaptive concurrency control QOS agent, which is running on RCSM(Reconfigurable Context Sensitive Middleware) for ubiquitous networks. RCSM provides standardized commu-nication protocols to interoperate an application with others under dynamically changing situations. It describes a hybrid software architecture that is running on situation-aware middleware for a web based distance education system which has an object with a various information for each session and it also supports multicasting with this information. There are two approaches to software architecture on which distributed, collaborative applications are based. Those include CACV(Centralized-Abstraction and Centralized-View) and RARV(Replicated-Abstraction and Replicated-View). We propose an adaptive concurrency control QOS agent based on a hybrid software architecture which is adopting the advantage of CACV and RARV for situation-aware middleware. [ABSTRACT FROM AUTHOR]

We propose a novel multicast scheme that can provide quality-of-service (QoS) to multicast service over IEEE 802.11 wireless LANs by utilizing medium access control (MAC) layer relay. It is well known that IEEE 802.11 provides a physical layer multi-rate capability in response to different channel conditions, and hence packets may be delivered at a higher data rate through a relay node than through the direct link if the direct link has low quality and low data rate. We develop the distributed relay node selection algorithm and the relay channel selection algorithm. The effectiveness of proposed scheme is examined by numerical method and simulation. Simulations show that the proposed relayed multicast significantly improves throughput and delay performance. [ABSTRACT FROM AUTHOR]

We presents a power-aware routing protocol called Multi-Route Transmission Routing that utilizes multiple routes to transmit the data traffic simultaneously and leads to a balanced energy consumption. The proposed routing approach can extend the system lifetime of the network. A new routing decision index is also proposed for the route selection mechanism, which takes both the shortest-path and the maximum system lifetime into consideration and dynamically adjusts its weight between them according to the energy usage of the network. Experiment results show that, the proposed routing protocol provides a higher performance than other well-known power-aware routing protocols in terms of the energy-efficiency. [ABSTRACT FROM AUTHOR]