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With today’s developments in device miniaturization, wireless networking, such as PCs, PDAs, Cell phones, RFID tags and so on, we are facing great opportunities and challenges to realize the ubiquitous computing vision. In this paper, we first identify the key characteristics of ubiquitous computing systems; then argue that agents and agent networks are the right metaphor for managing the dynamism and complexity of system integration and on demand interactions in ubiquitous computing systems. [ABSTRACT FROM AUTHOR]

The existing parallelizing compilers can parallelize most of the loops with uniform dependences, but they do not satisfactorily handle loops with non-uniform dependences. Most of the time, the compiler leaves such loops running sequentially. Unfortunately, loops with non-uniform dependences are not so uncommon in the real world. This paper presents the two parallel region partitioning method of nested loops with non-uniform dependences for maximizing parallelism. By parallelizing anti dependence region using variable re-naming, we will divide the iteration space into two parallel regions by a line in case that FDT (Flow Dependence Tail set) does not overlap FDH (Flow Dependence Head set). Comparison with some related works shows more parallelism than other existing methods. [ABSTRACT FROM AUTHOR]

In the paper, a portable off-line OCR and bi-linguistic translation system (Chinese to English, English to Chinese)—Electronic Reading Pen (ERPen) is designed and implemented. The constitution of ERPen hardware is designed and several modules, including CCD line array acquisition, wheel driven unit, FLASH management and USB interface are implemented. Moreover, the embedded software, consisting of image preprocessing, character segmentation and recognition, and corpus based postprocessing, is also discussed and implemented. A novel segmentation approach, central growth algorithm, is proposed and applied in ERPen system. Experimental results have shown that ERPen is effective to tackle printed character recognition and translation. [ABSTRACT FROM AUTHOR]

The increasing quest for mobility bolster the integration of technology of computer supported cooperative work and mobile computing. In cooperative editing systems that integrated with embedded devices, inconsistency is one of the major problems. In this paper, locking scheme and the corresponding algorithm of locking conflict solution are proposed to maintain consistency of the distributed shared documents and enhance the efficiency of collaborative users. The scheme and algorithm are realized in CoEdit – a prototype system of collaborative editing system. [ABSTRACT FROM AUTHOR]

The paper addresses the problem of loading and upgrading mechanisms for embedded and distributed systems. Such mechanisms for most of the large operating systems have been developed over the recent years. However, custom embedded systems usually lack a proper solution, mostly due to their hardware varieties. In this paper the object-oriented design is presented that allows for reliable software loading and upgrading for many architectures of embedded systems regardless of their complexity and computational power. The proposed solution was implemented and tested on the real platform and showed great robustness. The paper can be of interest for designers of embedded and distributed computer systems. [ABSTRACT FROM AUTHOR]

The complexity of embedded applications is growing rapidly. Mainstream software technology is facing serious challenges for leaving out non-functional aspects of embedded systems. To achieve this goal, we have defined a component-based modeling and assembly infrastructure, Pcanel, that supports hierarchical integration of concurrent, runtime models. A key principal in Pcanel is its netlist, namely component connection network. Pcanel advocates netlist as global view of a systemic design, where the basic building block is component. The functionality of embedded system is modeled as netlist. The communication among components is modeled as token flow. The distribution of functionality on netlist is transparent from the runtime models, which makes communication refinement easier. When applied formal models to components, the resulting runtime netlist maintains assurance of diversified non-functional aspects, such as timing and deadlock. The infrastructure advances the synergy between design-time models and runtime models. [ABSTRACT FROM AUTHOR]

The main issue of today’s software development process is how to relate the schedule and coding of the software project. The chaos model of software development gave a theoretical description for it. This paper introduces the chaos model into the research of software architecture and brings forward a new software development framework CBFSD, which divides the process of software development into three levels: tasks level, codes level and components level. The construction of components level’s architecture is the core of the whole framework. In this framework, we use the chaos strategy: ”Resolve the most important issue first.” The strategy makes it more appropriate to design and develop complicated software systems. [ABSTRACT FROM AUTHOR]

Development of multi-task embedded software involves very complex modeling process. Based on the data flow diagram (DFD) method, a structure modeling method for multi-task embedded system design is present in this paper. This structure modeling approach mainly depends on the task-based DFD method. As a concrete instance, the development of a project on IMS detector design is discussed using above method. It is true that DFD-based structure model is an effective solution for some real time embedded system design [ABSTRACT FROM AUTHOR]

The administration of heterogeneous networks with many embedded equipments and mobile devices is a hard and time-consuming task. Today’s methods only provide static configuration files and make the addition and removal of devices a manual chore. The Open Services Gateway Initiative (OSGi) specification defines a service-oriented framework for use in residential gateways. OSGi framework acts as a gateway from the Internet to consumer devices attached to the residence’s home-area network. And Jini is an infrastructure for spontaneous and ad hoc service networks. It allows users to find services which consumer devices provide without prior knowledge of their network environments. The paper presents a cooperative web framework for the integration of Jini into OSGi open home gateway which can provide much easier, more intelligent and powerful home network control service. It can federate home-area network devices and services in secure ways by Internet. This paper puts forward relative design and reference implementation. [ABSTRACT FROM AUTHOR]

The development of distributed, concurrent software in embedded systems is becoming increasingly complex and error-prone. Model-based integration of reusable components is advocated as the method of choice. To this end, we propose a framework to support component-based model integration, hierarchical functionality composition, and reconfiguration of systems with continuous and discrete dynamics. In this framework, components are designed and used as building blocks for integration, each of which is modeled with abstract ports, reactions, and communication schemes. It uses hierarchical composition to hide the implementation details of components, and keeps the components at the same level of hierarchy interacting under a well-defined model of computation. Code generation takes the design decisions down to the final running system. Within this framework, embedded software can be constructed by selecting and then connecting components in a functionality repository, specifying models and transforming them to executable codes. [ABSTRACT FROM AUTHOR]

It is necessary to compute the execution time upper bound of embedded hard real-time program under the worst condition in embedded system design, which decides how hardware and software to partition and how to schedule process. Modern microprocessor which uses instruction cache memory and instruction pre-fetching increases the difficulty to compute the upper bound accurately. A new estimation method of embedded software performance based on instruction cache and pre-fetching model is proposed, which uses control flow graph and cache conflict graph and combine instruction pre-fetching into instruction cache analysis. It makes the execution time upper bound estimation under worst condition more accurate. [ABSTRACT FROM AUTHOR]

The continuous advances in microelectronics design are creating a significant challenge to design validation in general. Tackling pipelined microprocessors is remarkably more demanding. This paper presents a methodology to automatically produce a test program for simulation-based validation of microprocessors maximizing the given verification constraints. The approach integrates an accurate c-simulator to trace internal states, including memory access patterns, cache states, pipeline states and so on, of the target processor to generate test vectors with higher efficiency. The test program generator is integrated into a co-verification environment, which is used to verify an embedded processor with a 7-statge pipeline developed by our team and gained remarkable effects. [ABSTRACT FROM AUTHOR]

In system functional verification, collaborative method is an effective technique. Co-SAM verification platform employs three verification methods, static analysis, logic simulation and model checking, to implement verification process. With the collaborative platform, system properties are classified and verified. A whole model for a system inclines to ineffectiveness and states explosion during verification. Model refinement is indispensable. This paper presents special optimization techniques for verification model refinement, i.e. property grouping, signals reordering, and model hierarchizing. Experimental results demonstrate the validity of these optimization techniques in system functional verification. [ABSTRACT FROM AUTHOR]

This paper is a case study of the verification of a seven-segment LED display decoder circuit design, in which two popular verification tools, HOL and PVS, are compared and evaluated. [ABSTRACT FROM AUTHOR]

Core-based system-on-chip (SoC) design is quickly becoming a new paradigm in electronic system design due to the reusability of IP cores. However, the validation of IP cores is the most time consuming task in the design flow. This paper presents EmGen, an automatic test-program generation tool designed for embedded microprocessor cores. EmGen provides an configurable formal specification model with heuristic knowledge, which can generate test programs according to different configuration of microprocessors’ architecture, a test generation scheme based on heuristic algorithms, which can efficiently provide instructions in test programs, and validation testbenches, which support simulation with generated test programs automatically and check the equivalence of microprocessors and the specified instruction reference model. EmGen is currently in use at ICT for the verification of embedded microprocessor cores. Experiments results show that EmGen can improve verification process and cut down skilled manpower obviously. [ABSTRACT FROM AUTHOR]

In this paper, we present a two-phase approach to generate test data for the EFSM model of an embedded operating system. We first build the EFSM model of the system. The model can then be used to automatically generate test data for testing of APIs. We also point out certain issues that need further study. [ABSTRACT FROM AUTHOR]

This paper presents an efficient verification method for microprocessors based on virtual machine. Under memory and I/O device models provided by the virtual machine, our simulation tool can not only simulate test programs but also operating systems. This simulation environment is close to the real environment of microprocessors, so it is sufficient for functional verification of microprocessors before tape out. At the same time, our simulation tool can automatically compare the simulation results using the virtual machine as reference model and find the error positions. This method takes full advantage of the virtual machine and greatly improves speed and efficiency of the verification procedure. This method has been successfully applied in the verification of an embedded microprocessor Amex86 designed in our laboratory for six months by five persons. [ABSTRACT FROM AUTHOR]

Developing distributed embedded systems based on Internet and Web technologies is a relative new trend in computer technologies. The paper shows the tree-layer client-server model in developing web-based distributed embedded systems. It also presents a model-driven approach for generating quality-of-service (QoS) adaptation in Distributed Real-time Embedded (DRE) Systems. Our control task model consists of the target task to be controlled, the adaptation task that implements the control algorithm. We have built a prototype of a middleware system which verifies our control model and shows the soundness of our approach. A detailed experimental analysis is also presented in this paper. Key Words. Quality of Service (QoS); Real Time; Embedded Systems; Distributed Computation [ABSTRACT FROM AUTHOR]

Strongly partitioned real-time systems have been adopted to provide an integrated run time environment for applications with varied criticalities. This is achieved by guaranteeing spatial as well as temporal partitioning for the applications. To enable accesses to shared I/O devices in such an environment, this paper provides an effective model that the co-existence of any application does not hinder the execution of IO operations or spatial and temporal requirements of other applications. The model utilizes a microkernel-based approach to regulate the work of drive drivers and thus integrate the device-sharing model with the microkernel. [ABSTRACT FROM AUTHOR]

An integrated solution to guarantee real-time requirements in embedded real-time monitor and control systems is presented in this paper. First a typical task model is abstracted from such a control system, together with specific characteristics of the tasks. These system characteristics lead to a hybrid scheduling policy of the rate monotonic algorithm and the sporadic server algorithm. The feasibility and rationality of such a policy are also analyzed. The rate monotonic algorithm is extended in this paper, providing a schedulability test that incorporates factors such as context switching overhead and task synchronization. [ABSTRACT FROM AUTHOR]

Recent work showed that staging and abstract interpretation can be used to derive correct families of combinatorial circuits, and illustrated this technique with an in-depth analysis of the Fast Fourier Transform (FFT) for sizes 2n. While the quality of the generated code was promising, it used more floating-point operations than the well-known FFTW codelets and split-radix algorithm. This paper shows that staging and abstract interpretation can in fact be used to produce circuits with the same number of floating-point operations as each of split-radix and FFTW. In addition, choosing between two standard implementations of complex multiplication produces results that match each of the two algorithms. Thus, we provide a constructive method for deriving the two distinct algorithms. [ABSTRACT FROM AUTHOR]

Programming in Java is attractive for its maintainability and reliability, but much work is to be performed to apply it into the real-time software development. We try to address the two main issues, thread scheduling and garbage collection, with real-time concerns. Besides, the extra memory requirement caused by the introduction of garbage collection in systems is carefully concerned. As a result, a concurrent garbage collector that combines incremental collection and real-time scheduling is figured out and implemented in a standard JVM, which plays a key role in our future real-time JVM. [ABSTRACT FROM AUTHOR]

An adaptive fault tolerance scheme aiming at those real-time embedded systems that have single processor and limited resources is presented in this paper. As the fault behavior exhibited by system changes with time and environment, it can decide a suitable strategy among various reliable techniques that have been introduced into application software. Prediction on fault emergence is made by strategy decider according to its memory of fault emerging history. The application module is assigned to contact with fault tolerance controller through its stubs. Performance of the scheme is measured and evaluated in experiment. Some parameters are also discussed. [ABSTRACT FROM AUTHOR]

In all kinds of dynamic power management (DPM) policies, the timeout policy works perfectly in practice, but this could not be elucidated in the traditional queuing theory. With the pareto distribution, the drawback of the exponential distribution was overcome, and this phenomena was explained well. The conclusion provided the theoretical basis for the simplification of DPM algorithm. In this paper, a simple DPM algorithm was described when the length of idle time follows the Pareto distribution. The simulation result testified the conclusion above. [ABSTRACT FROM AUTHOR]

In this paper we present a new modeling technique using software engineering tool Flow Model for modeling and solving the Dynamic Power Management (DPM) with complex behavioral characteristics. Using this tool we can model the whole system easily. Experimental results show that the proposed technique can achieve more than 12% power saving compared to other DPM techniques. [ABSTRACT FROM AUTHOR]

This paper presents a novel strategy aimed at modeling the instruction energy consumption of ARM microprocessors with dynamic voltage scaling (DVS) support. A novel energy estimation algorithm is designed, which can record the function calls, and generate a detailed energy profile for each function in a specific program. Some of the optimization policies for implementation are also discussed. These optimization policies reduce the workload of the energy estimators for the individual SOC systems. The prototype system, SKYEYE, can automatically detect the voltage/frequency variation activated by DVS system, and adjust the energy estimation model accordingly. The experiment results further prove the effectiveness of the algorithm. [ABSTRACT FROM AUTHOR]

Dynamic Power Management (DPM) is an effective power reduction technique to dynamically control power state of system components. Although there are already a lot of papers on DPM, few of them present robust and adaptive solution to handle the inherent time varying behavior of real world system. In this paper, we propose techniques for targeting DPM on the time varying behaviors. In our approach, we apply efficient policy optimization method to generate online power management policy to achieve adaptiveness. Moreover, in order to handle the small scale varying behavior (perturbation) that tends to significantly degrade the performance of DPM, we apply the Bounded Parameter Markov Decision Process and Interval Value Iteration to derive robust policy tolerant to perturbations. Simulation results show that the proposed techniques are effective. [ABSTRACT FROM AUTHOR]

This paper describes a functionality-based instruction-level power analysis model, which aims at reducing workload of computing inter-instruction power and keeping the convenience to observe necessary parameters from a source-code description. The model treats the total power as the sum of basic power of individual functional component and switching power of consecutive components pairs. To get the switching power, the switching activities between two functional components are treated as one changing from working state to sleeping state and the other from sleeping state to working state. NOP instructions are used to model transitions between the two states. The model is experimentally validated on a wide range of embedded software routines. Experiments show that our model is within 95% accuracy on the average, and can reduce the workload from a complexity of O(n2), which is the workload of traditional instruction-level energy estimation techniques, to a complexity of O(n). [ABSTRACT FROM AUTHOR]

This paper puts forward SmartOSEK, a dependable platform for automobile electronics, which consists of an operating system compliant with OSEK/VDX specifications and an integrated development environment (IDE) that consists of many convenient tools, such as visual designer, system generator, time analyst, scheduling analyst, and running tracer. In the operating system, SmartOSEK OS and SmartOSEK COM are presented. In the IDE, we apply the graphic design, automatic code generation and time analysis to help developers devote their mind to the modeling of the applications. A design example of automated transmission system based on SmartOSEK platform is given, and good results are achieved. [ABSTRACT FROM AUTHOR]

A brief survey for recent research works on embedded operating systems (EOSs) is presented, including component based EOSs, energy-aware EOSs, secure EOSs, and EOSs for sensor networks. [ABSTRACT FROM AUTHOR]

This paper presents a flexible binding implementation in JBEOS, a component based embedded operating system targeted at resource-constrained devices. This binding model features an extensible framework, which consists of two stub segments named prolog and epilog respectively. By making the binding service an ingredient of the run-time infrastructure, dynamic loading and binding of system components is supported in JBEOS. Synchronization, mutual exclusion issues are made transparent by manipulating the inter-component communications using the binding model given. [ABSTRACT FROM AUTHOR]

This paper presents a new approach to develop device drivers for embedded system: Devil+ language [3, 4, 7] which can automatically generate device driver code [9]. It demonstrates the whole process to develop embedded system device driver with this new language. The example project selects SHARP KEV79520 as hardware platform [8], DeltaOS as software platform [5, 6, 7]. Development processes are illustrated with source code. Some programming details are also explained in this paper. Finally we illustrate the benefit of the new methodology in embedded system development with the comparison between the Devil+ approach and the traditional raw C language method. [ABSTRACT FROM AUTHOR]

Embedded system with the kernel of embedded operating system becomes the ubiquitous computing unit now. Embedded operating system should be of hard real-time, high reliability and high availability. Aiming at satisfying the demands of applications, based on analyzing the existing three kinds of operating system architectures and some new design technologies, this paper presents a novel design of operating system which is based on resolved and intelligent daemon and agent-based coordination managing components. [ABSTRACT FROM AUTHOR]

Liquid meta-service, a component-based operating system layer, is intended to enable embedded operating system to support pervasive computing by meeting the requirements of being spontaneous and adaptive. This is accomplished through two key features: (1) configurable, component-based infrastructure services called meta-service, and (2) a meta-service components trading service, which provides selecting and configuring mechanism for meta-service components. In this paper, we discuss the design principle, component model, implementations of some meta-service, and analyze the performance impact of using meta-service in embedded operating system. [ABSTRACT FROM AUTHOR]

Heterogeneous computing environments have been widely used in real-time embedded systems. Efficient task scheduling is essential for achieving reliability in embedded systems. In this paper, an algorithm called the Real and Reliable Scheduling (RRTS) has been proposed to improve the system reliability. The RRTS algorithm is achieved by applying a reliability model to a List Scheduling algorithm. The algorithm firstly calculates Earliest-Finish-Times (EFTs) and reliability costs of a task in every processor. Then the minimum EFT is selected. Finally, the task is scheduled to a processor according to the EFT and reliability costs. The experimental results and examples show that the algorithm can improve system reliability significantly while maintaining high performance. [ABSTRACT FROM AUTHOR]

Deadlock avoidance algorithms help to improve fault tolerance feature of computer system. Unfortunately, few current algorithms are useful to embedded system either because they only work with single-unit resources, or because the time cost is too high. This paper improves the reduction algorithm with tree structure. According to the new algorithm, only multi-unit resources and the root process in each tree are considered when reducing, while single-unit resources and other processes are ignored because they are combined with tree structure. Thus the new algorithm works with all kinds of resources and its time cost is lower. The new algorithm is useful to embedded system. [ABSTRACT FROM AUTHOR]

The paper presents advanced task management techniques featuring Boolean vectors and bitwise vector operations on kernel data structures in the context of the HARTEXTM hard real-time kernel. These techniques have been consistently applied to all aspects of task management and interaction. Hence, the execution time of system functions no longer depends on the number of tasks involved, resulting in predictable, jitter-free kernel operation. This approach has been further extended to time management resulting in a new type of kernel component, which can be used to implement timed multitasking - a novel technique providing for jitter-free execution of hard real-time tasks. [ABSTRACT FROM AUTHOR]

VCNs (Virtual-Connection Networks) of gigabit-ethernet can be efficiently used to transport packet data services. The switching system will sup-port voice and packet data services simultaneously from end to end applications. To guarantee quality of service (QoS) of the offered services, source rate to send packet data is needed to control the network overload condition. Most existing control algorithms are shown to provide the threshold-based feedback control technique. However, real-time voice calls can be dynamically connected and released during data services in the network. If the feedback control information delays, quality of the serviced voice can be degraded due to a time delay between source and destination in the high speed link. An adaptive algorithm based on the optimal least mean square error technique is presented for the predictive feedback control technique. The algorithm attempts to predict a future buffer size from weight factor (slope) adaptation of unknown functions, which are used for feedback control. Simulation results are presented, which show the effectiveness of the algorithm. [ABSTRACT FROM AUTHOR]

The advent of technology has facilitated the development of small, low power devices that combine programmable general purpose computing with multiple sensing and wireless communication capability. This article discusses the characteristics of sensor network and compares its communication mode with MANET, and then it introduces the clustering sensor network architecture. The nodes in this architecture can be classified as the following four types: cluster head nodes, active nodes inside cluster, the dormancy nodes and free nodes. An energy cost model in the sensor network is given in the article. The energy cost simulation is done and the influence of clustering on the energy cost is analyzed. [ABSTRACT FROM AUTHOR]

An Embedded Fiber Sensor Network (EFSN) is a health monitoring network for large structure consisted of several sensor nodes, each equipped with fiber-optic sensor, embedded processor, and data transceiver. The collective sensing data of such a system of networked sensors can be utilized to evaluate structural health conditions of bridges, elevators, composites, mines, and even reactors. Key concerns for designing such networks are real-time detection, data synchronization and reliable information submission. This paper addresses these issues and presents an Independent Circular Cache Queue (ICCQ) to reduce the amount of traffic in the network. In the ICCQ mechanism, a self-managed scheme is implemented in the network to maintain stability under varying environmental disturbance and sensor sensitivities. [ABSTRACT FROM AUTHOR]

This paper combines OPC (OLE for Process Control) standard to EWS (Embedded Web Server) in order to distribute an integrated service for accessing real-time and history data from control networks. A layer of OPC XML-DA (Data Access) service is added between web services interfaces and embedded operation system in OPC-EWS. Architecture of DCS (Distributed Control System) with OPC-EWS is described too. This OPC-EWS applies such technologies as OPC, Java and XML and links to Internet through TCP/IP. Therefore, accesses to all kinds of embedded devices and data share in the heterogeneous Internet/Intranet environment are implemented. At last real-time performance and security of OPC-EWS are analyzed. The experiments and application have demonstrated that the architecture has good performance and is feasible for real-time operation in DCS. [ABSTRACT FROM AUTHOR]

In future application environments, wireless sensor networks may comprise tens of thousands of nodes and multiple applications will be executed concurrently. Until now, WSNs and their applications have been developed without considering a management scheme. In this article we discuss the management technologies for WSNs. We identify what is SNM and its necessities. Based on multi-sensor management technologies in data fusion, we propose a feedback management framework for WSNs. Finally, a macro-micro management architecture for hierarchical WSN is also proposed. [ABSTRACT FROM AUTHOR]

In this paper, a robust active queue management system to secure high utilization as well as bounded delay and loss is designed. Using this system, the network complies with the demands each traffic class set. We use Fuzzy Proportional-Integral-Derivative (PID) controller in which the parameters of PID controllers are tuned based on fuzzy logic. The proposed controller is simple to implement as well as robust due to the nature of fuzzy controller. Simulation results of the proposed control action demonstrate the effectiveness of the controller in providing robust queue management system. [ABSTRACT FROM AUTHOR]

Weighted Fair Queuing (WFQ) is a good approximation of Generalized Processor Sharing (GPS) service principle, and can provide the delay guarantee when the bandwidth and the burst size are assured. Thus, WFQ can not satisfy the stringent delay requirement of some real-time networked applications with large burst size, such as video transmission. In order to better serve these applications, (m,k)-firm guarantee is integrated in QoS architecture. A fluid scheduling algorithm, (m,k)-GPS, and its packet approximating scheduling algorithm, (m,k)-WF2Q ,are proposed. Dropping some optional packets, they guarantee low delay to flows with large burst size. Moreover, the fairness and computing complexity of (m,k)-WF2Q are the same as WF2Q. [ABSTRACT FROM AUTHOR]

Decisions on the number of clusters and the sensing radius will effectively affect the quality and energy metrics of WSN (wireless sensor networks) tracking systems. By presenting the mean number of the detectable sensors as a trajectory independent quality metric, an energy-quality optimization model is derived and Pareto based optimization strategy is proposed. The obtained non-bad solutions (Pareto Fronts) can be used to direct the clusters partition and sensors configuration. Comparing with simulation, more than 80% of these Pareto Fronts are coincident with those in experiment results. [ABSTRACT FROM AUTHOR]

Although numerous wireless network protocols are well-studied today, few of them are feasible for super-micro wireless networked sensors with the seriously limited system. In this paper, we present a MAC protocol named ”ST-MAC (Sensor Media Access Control protocol based on TDMA)” for wireless networked sensors with the seriously limited resource. Performance analysis in theory and experimental measurements indicate that ST-MAC achieves efficient transmission control with high packet delivery success rate, fair bandwidth allocation and acceptable adaptive ability. [ABSTRACT FROM AUTHOR]

A new gradient-based routing protocol is proposed in this paper. It takes into account the minimum hop count and remaining energy of each node while relaying data from source node to the sink. The optimal routes can be established autonomously with our protocol. A simple acknowledgement scheme, which can be implemented without extra overheads, is proposed. Our protocol also employs data aggregation to save transmission energy. To handle the frequent change of the topology of the network, one scheme for topology update is provided. At last, simulation results illustrate the effect of system parameters on the protocol performance. [ABSTRACT FROM AUTHOR]

With the rapid development of wireless network technology and PMCN technology, people are strongly interested in wireless communication and network communication. A new architecture of EWMN is established based on Bluetooth, PMCN data communication, and embedded Linux, etc. The functions and applications of the new EWMN are discussed and studied in detail. The network structure of the EWMN can be divided into three layers: Bluetooth scatternet layer, PMCN layer, and Internet layer. The advantages of EWMN include: long-range application and flexible system configuration, lower equipment cost and communication expenses, and easy to control and manage. The basic key elements of EWMN are analyzed in detail. [ABSTRACT FROM AUTHOR]

The embedded web servers play very important part in embedded system. Controlling the timing performance of each individual request, such as CGI (Common Gateway Interface), between client and server is a challenging problem. CGI requests/responses not only are the useable access to interaction with the web server in embedded device, but also are executed in web server in real-timing performance of a network close to the service level specification. To ensure the CGI response within a specified time to meet the needs of real-time demand, the principal of the CGI queueing model in embedded web server is studied, and the approach to the problem of meeting relative delay guarantees in web servers is extended. Furthermore, the process of CGI request executed in server is divided into several subroutines, which is useful to reduce the CGI request response time. This web server has been successfully implemented in embedded platform for a real-time controlling system and the tested CGI response performance shows that the new CGI Queueing Model is efficient. [ABSTRACT FROM AUTHOR]

A future wireless network infrastructure is expected to be an all-IP based and supporting mobility between the Base Stations belonging to different types of network as well as belonging to the same network. There’re some wireless data infrastructures defined to provide some specific Function Units to manage the IP layer mobility. But most existed infrastructures provide no such Function Units. Here, we consider from the Mobile Station aspect to support the Mobile IP in current wireless network infrastructure. [ABSTRACT FROM AUTHOR]