Patent Publication Number: US-10776393-B2

Title: Synchronizing multiple devices

Description:
BACKGROUND 
     1. Field 
     The disclosure relates generally to methods for synchronously starting programs on devices connected to a server. Specifically, the methods dynamically inject a wait function into the program on each of the devices to control a start time for the devices. 
     2. Description of the Related Art 
     The internet of things (IoT) refers to the interconnectivity of physical things, such as devices, automobiles, trains, airplanes, and buildings. The IoT may provide direct integration of the physical things into computer-based systems. The IoT may permit grids, houses, transportation, and cities to collect and exchange data. Each of the physical things may be connected electronically by processors, software, and sensors to enable the collection and exchange of data. 
     In the IoT, each physical thing may be uniquely identifiable through its embedded computing system and may interoperate within an existing Internet infrastructure. In the area of transportation, vehicles may be connected to collect and exchange data regarding speed, direction, fuel efficiency, travel distance, and a record of travel destinations. Vehicle may include driverless cars. Testing of driverless cars may require the collection and exchange of data from devices located on each driverless car. Each device may have its own internal time. 
     Execution of time-critical test scenarios for driverless cars may depend on other devices. Execution of time-critical test scenarios may be difficult or impossible if the devices are not synchronized. Multiple devices need to be synchronously operated, not only for testing, but also for actual real-life operation. For example, devices may be temporarily stopped in order to change configuration information, and then simultaneously operated after the configuration change. Therefore, a need exists to start multiple driverless cars simultaneously. 
     SUMMARY 
     According to one illustrative embodiment, a computer-implemented method for synchronously starting programs on multiple devices connected to a server is provided. A synchronous point of a program to be synchronously started for each of the multiple devices is identified. A wait function is dynamically injected into the synchronous point for each of the multiple devices. A start time, from the server, is received in response to the multiple devices entering a waiting state. The programs are synchronously started in response to the start time arriving for each of the multiple devices. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a pictorial representation of a network of data processing systems in which an illustrative embodiment may be implemented; 
         FIG. 2  is a diagram of a data processing system in which an illustrative embodiment may be implemented; 
         FIG. 3  depicts a schematic illustrating a configuration for synchronizing multiple devices using edge gateways, an application server, and a time server and device management application in accordance with an illustrative embodiment; 
         FIG. 4  depicts a schematic illustrating a configuration for synchronizing multiple devices using edge gateways, an application server, and a time server and device management application illustrating a process in accordance with an illustrative embodiment; 
         FIG. 5  depicts a schematic illustrating a configuration for synchronizing multiple devices in an edge gateway in accordance with an illustrative embodiment; 
         FIG. 6  depicts a schematic illustrating injection of a wait function in accordance with an illustrative embodiment; 
         FIG. 7  depicts a schematic illustrating injection of a wait function in accordance with an illustrative embodiment; 
         FIG. 8  is a flowchart illustrating a process for synchronizing multiple devices in accordance with an illustrative embodiment; 
         FIG. 9  is a flowchart illustrating a process for dynamically inserting a wait function in accordance with an illustrative embodiment; and 
         FIG. 10  is a flowchart illustrating a process for dynamically releasing a wait function in accordance with an illustrative embodiment. 
         FIG. 11  is a flowchart illustrating a number of triggers for sending a start time in accordance with an illustrative embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     In an illustrative embodiment, synchronization may be performed with multiple devices in multiple gateways. As used herein, an edge gateway is a virtual router for networks that may be virtual device context networks. Preparation periods from the activation of the devices to the actual transmission of the data may be aligned to allow the data to be synchronously transmitted. Synchronous points of programs on multiple devices may be identified by a server. A wait function may be injected dynamically into the synchronous point for each of the multiple devices. As used herein, “wait function” means a function that provides inter-thread synchronization or process-process synchronization on an operating system, on different operating systems and for multiple devices on an Edge gateway. In an illustrative embodiment, a wait function may assign a start time. Changes in configuration information may be distributed from the server. Changes in configuration information may be changes in a type of data to be acquired, in the time intervals for acquisition of data, and in designations of data format. In order to make the changes in configuration information, devices may be temporarily suspended by the injected wait function. Each device is informed of the information. The devices are initialized. As used herein, initialization is the assignment of an initial value for a data object or variable. A time server and device management function may detect that the initialization of all the devices is finished and send a start time to release the wait function and execute the changes in the multiple devices in the multiple gateways. At the start time, changes to the device are performed. The time server and device management function insures that changes are performed synchronously. 
     In automotive applications of IoT, data devices may be created to acquire and read test data in vehicles. Data devices in the vehicles may need to be operated simultaneously in multiple edge gateways. Situations may arise where multiple data from separate devices must be recorded at the same moment. Location data, such as longitude and latitude from a car-navigation device or speed data from a vehicle body device, may need to be recorded at the same moment to prevent inconsistencies. Inconsistencies may arise from time lags due to manual activation or the state of the devices. If a time lag occurs, data acquired from vehicles running at a certain interval may not reflect the same intervals. Indeed, in the case of a driverless car, if the data is used to control the driverless car, a collision may occur due to the differences in data. 
     Even if a device is designed to operate a particular action at a predetermined interval, such as a recording and sending sensor data, it may be difficult or impossible to completely synchronize the device with other devices. An example may be data unit conversion. Configuration of vehicle devices may require conforming data from one device in kilometers per hour with data from other devices in miles per hour. Data units may need to be converted at the same time in all devices. 
     Synchronization with a time server may be used to insert the wait function. The edge gateway may synchronize with the time server when activated. When there is a wait function for each device, synchronization may be performed at a designated time referred to as a “start time”. In an illustrative embodiment, designated time is designated by relative time elapsed in seconds after an occurrence of a trigger. The time server converts the relative time into absolute time and sends the absolute time to each device. When there is a manager in the device, the manager may serve as a relay for the time server and the wait function. 
     A start time may be designated by relative time elapsed, in seconds, after an occurrence of a certain state. A time server and device management function may convert the relative time into absolute time and send the absolute time to each device. The wait function may be released at the start time. The start time may be different for each device. 
     Triggers may be employed for sending the start time. A trigger may be when a particular device enters a waiting state. A trigger may be when wait functions in all devices cause the devices to enter waiting states. A trigger may be when a plugin manager of the edge gateway or a time server is informed that all devices have entered waiting states. A trigger may be when a property file of a time server indicates that multiple devices have entered a waiting state. 
     The programs may be synchronously started in response to the start time arriving for each of the multiple devices. The start time received by one of the multiple devices may be different from the start time received by another one of the multiple devices. The server may be provided with a function of a time server and each of the multiple devices may be synchronized with the time server. Time may be corrected in the device. A system for synchronously starting programs on multiple devices connected to a server, may comprise a bus system, a storage device connected to the bus system, and a processor connected to the bus system, wherein the storage device stores program instructions and the processor executes the program instructions to identify a synchronous point of a program to be synchronously started for each of the multiple devices and to dynamically inject a wait function into the synchronous point for each of the multiple devices. As used herein a “synchronous point” is a point selected dynamically by a computer system to embed a wait function into the source code of a program in accordance with one or more criteria. In an illustrative embodiment, a synchronous point to embed a wait function into the source code of a program may be selected manually by a programmer at a display. In an illustrative embodiment, the point at which the wait function is embedded may be the end of an initialization part of a start method. In another illustrative embodiment, wait functions may be embedded into the source code when the source code is written. In another illustrative embodiment a programmer may use a graphical user interface to select a point to insert a wait function, and then to dynamically inject the wait function into the program at a selected point. In an illustrative embodiment, the selected point may be the point at which initialization is finished. Dynamic insertion may be accomplished by the computer system automatically determining a time at which initialization is finished, and dynamically injecting the wait function into the part of the program at which initialization is finished so that the synchronous point is established by the computer system. Other criteria may be used in other embodiments. In an illustrative embodiment, when a thread class is defined such as Java and the thread class is extended to implement the class, a start method generally includes an initialization part. The wait function may be dynamically injected at the end of the initialization part of the start method. The storage device may store further program instructions and the processor execute the further program instructions to receive a start time from the server in response to the multiple devices entering a waiting state and synchronously start the programs in response to the start time arriving for each of the multiple devices. Time may be corrected in the device. The start time may not be relative time. The start time may be absolute time. The start time may be received from the server, and the wait function may be released when the start time arrives. 
     The present invention may be a system, a method, and/or a computer program product. The computer program product may include a computer readable storage medium or media, having computer readable program instructions thereon for causing a processor to carry out aspects of the present invention. 
     The computer readable storage medium can be a tangible device that can retain and store instructions for use by an instruction execution device. The computer readable storage medium may be, for example, but is not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. A non-exhaustive list of more specific examples of the computer readable storage medium includes the following: a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanically encoded device such as punch-cards or raised structures in a groove having instructions recorded thereon, and any suitable combination of the foregoing. A computer readable storage medium, as used herein, is not to be construed as being transitory signals per se, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through a waveguide or other transmission media (e.g., light pulses passing through a fiber-optic cable), or electrical signals transmitted through a wire. 
     Computer readable program instructions described herein can be downloaded to respective computing/processing devices from a computer readable storage medium or to an external computer or external storage device via a network, for example, the Internet, a local area network, a wide area network and/or a wireless network. The network may comprise copper transmission cables, optical transmission fibers, wireless transmission, routers, firewalls, switches, gateway computers and/or edge servers. A network adapter card or network interface in each computing/processing device receives computer readable program instructions from the network and forwards the computer readable program instructions for storage in a computer readable storage medium within the respective computing/processing device. 
     Computer readable program instructions for carrying out operations of the present invention may be assembler instructions, instruction-set-architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, firmware instructions, state-setting data, or either source code or object code written in any combination of one or more programming languages, including an object oriented programming language such as Smalltalk, C++ or the like, and conventional procedural programming languages, such as the “C” programming language or similar programming languages. The computer readable program instructions may execute entirely on the user&#39;s computer, partly on the user&#39;s computer, as a stand-alone software package, partly on the user&#39;s computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer may be connected to the user&#39;s computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer, for example, through the Internet using an Internet Service Provider. In some embodiments, electronic circuitry including, for example, programmable logic circuitry, field-programmable gate arrays (FPGA), or programmable logic arrays (PLA) may execute the computer readable program instructions by utilizing state information of the computer readable program instructions to personalize the electronic circuitry, in order to perform aspects of the present invention. 
     Aspects of the present invention are described below with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer readable program instructions. 
     These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions or acts specified in the flowchart and/or block diagram block or blocks. These computer program instructions may also be stored in a computer readable medium that can direct a computer, other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions stored in the computer readable medium produce an article of manufacture including instructions which implement the function or act specified in the flowchart and/or block diagram block or blocks. 
     The computer readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable apparatus or other device to produce a computer implemented process, such that the instructions which execute on the computer, other programmable apparatus, or other device implement the functions/acts specified in the flowchart and/or block diagram block or blocks. 
     The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in the flowcharts or block diagrams may represent a module, a segment, or a portion of instructions, which comprises one or more executable instructions for implementing the specified logical functionor functions. In some alternative implementations, the functions noted in the blocks may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustrations, and combinations of blocks in the block diagrams and/or flowchart illustrations, can be implemented by special purpose hardware-based systems that perform the specified functions or acts or carry out combinations of special purpose hardware and computer instructions. 
     With reference now to the figures, and in particular, with reference to  FIGS. 1-7 , diagrams of data processing environments are provided in which illustrative embodiments may be implemented. It should be appreciated that  FIGS. 1-7  are only meant as examples and are not intended to assert or imply any limitation with regard to the environments in which different embodiments may be implemented. Many modifications to the depicted environments may be made. 
       FIG. 1  depicts a pictorial representation of a network of data processing systems in which illustrative embodiments may be implemented. Network data processing system  100  is a network of computers and other devices in which the illustrative embodiments may be implemented. Network data processing system  100  contains network  102 , which is the medium used to provide communications links between the computers and the other devices connected together within network data processing system  100 . Network  102  may include connections, such as, for example, wire communication links, wireless communication links, and fiber optic cables. 
     In the depicted example, server  104  and server  106  connect to network  102 , along with storage  108 . Server  104  and server  106  may be, for example, server computers with high-speed connections to network  102 . In addition, server  104  or server  106  may, for example, manage recovery of a customer workload after failure of a primary computing environment executing the customer workload. The failed primary computing environment may be, for example, a server or a set of servers in a data center environment or a cloud environment. Server  104  or server  106  also may generate a secondary virtual machine seed image storage at a secondary data processing site for the failure recovery. The configuration of the secondary data processing site is similar to the configuration of the primary data processing site. 
     Client  110 , client  112 , and client  114  also connect to network  102 . Clients  110 ,  112 , and  114  are clients of server  104  and/or server  106 . Server  104  and server  106  may provide information, such as boot files, operating system images, virtual machine images, and software applications to clients  110 ,  112 , and  114 . 
     In this example, clients  110 ,  112 , and  114  may each represent a different computing environment. A computing environment includes physical and software resources used to execute a set of one or more customer workloads or tasks. A computing environment may comprise, for example, one server, a rack of servers, a cluster of servers, such as a data center, a cloud of computers, such as a private cloud, a public cloud, or a hybrid cloud, or any combination thereof. In addition, each of clients  110 ,  112 , and  114  may be a primary data processing site or a secondary data processing site. A primary data processing site initially executes a customer workload using a set of primary virtual machines and images. A secondary data processing site executes the customer workload using a set of secondary virtual machines and seed images when one or more primary virtual machines fail while processing the customer workload at the primary data processing site. 
     Storage  108  is a network storage device capable of storing any type of data in a structured format or an unstructured format. The type of data stored in storage  108  may be, for example, a list of computing environments with corresponding available resources, a list of primary data processing sites, a list of secondary data processing sites, a list of customer workloads, a plurality of virtual machine images, and the like. Further, storage unit  108  may store other types of data, such as authentication or credential data that may include user names, passwords, and biometric data associated with system administrators, for example. 
     In addition, it should be noted that network data processing system  100  may include any number of additional servers, clients, storage devices, and other devices not shown. Program code located in network data processing system  100  may be stored on a computer readable storage medium and downloaded to a computer or other data processing device for use. For example, program code may be stored on a computer readable storage medium on server  104  and downloaded to client  110  over network  102  for use on client  110 . 
     In the depicted example, network data processing system  100  may be implemented as a number of different types of communication networks, such as, for example, an internet, an intranet, a local area network (LAN), and a wide area network (WAN).  FIG. 1  is intended as an example only, and not as an architectural limitation for the different illustrative embodiments. 
     With reference now to  FIG. 2 , a diagram of a data processing system is depicted in accordance with an illustrative embodiment. Data processing system  200  is an example of a computer, such as server  104  in  FIG. 1 , in which computer readable program code or instructions implementing processes of illustrative embodiments may be located. In this illustrative example, data processing system  200  includes communications fabric  202 , which provides communications between processor unit  204 , memory  206 , persistent storage  208 , communications unit  210 , input/output unit  212 , display  214  and Edge gateways  215 . 
     Processor unit  204  serves to execute instructions for software applications and programs that may be loaded into memory  206 . Processor unit  204  may be a set of one or more hardware processor devices or may be a multi-processor core, depending on the particular implementation. Further, processor unit  204  may be implemented using one or more heterogeneous processor systems, in which a main processor is present with secondary processors on a single chip. As another illustrative example, processor unit  204  may be a symmetric multi-processor system containing multiple processors of the same type. 
     Memory  206  and persistent storage  208  are examples of storage devices  216 . A computer readable storage device is any piece of hardware that is capable of storing information, such as, for example, without limitation, data, computer readable program code in functional form, and/or other suitable information either on a transient basis and/or a persistent basis. Further, a computer readable storage device excludes a propagation medium. Memory  206 , in these examples, may be, for example, a random access memory, or any other suitable volatile or non-volatile storage device. Persistent storage  208  may take various forms, depending on the particular implementation. For example, persistent storage  208  may contain one or more storage devices. For example, persistent storage  208  may be a hard drive, a flash memory, a rewritable optical disk, a rewritable magnetic tape, or some combination of the above. The media used by persistent storage  208  may be removable. For example, a removable hard drive may be used for persistent storage  208 . 
     In this example, persistent storage  208  may store programs  220  and data  240 . Programs  220  may include time server and device management  230  and injector  232 . Injector  232  may be configured for dynamic injection of a wait routine into any function so that the wait routine may be embedded in the function. Injector  232  may comprise any technology that may embed a wait routine in any function. For example, a wait routine may be embedded at the beginning of a start function to start the process. Thus, when the process having the start function and the embedded wait routine runs, the process may wait before executing an original start because the wait routine causes the process to wait until an appointed time. Further, when all processes have a start function and a wait routine embedded, all processes can be run synchronously at an appointed time. The name of the start function may be arbitrary. For example, a name of a start function of process A may be “begin” and a name of a start function of a process B may be “run”. Injector  232  may use API Hook  244  in data  240  to hook “begin” function for process A and to hook “run” function for process B. As used herein, “hooking” means one or more techniques to change the behavior of an operating system, an application, or a software component by intercepting one or more function calls, messages, or events. As used herein, “hook” means code that performs the interception of the function calls, events, or messages. API Hook  244  may be located in load library  246 . Load library  246  may be a dynamic load library (DLL). Persistent storage  208  may also store the following programs or functions: time stamp  221 , graphical user interface (GUI)  222 , initialization function  224 , plug-in manager  231 , absolute time  233 , device plug-in  234 , and start times  235 . 
     Data may include target process  242 , API hook  244 , synchronized data  241 , start points  245 , load library  246 , wait function or routine  248 , and breakpoints  249 . Devices  260  may be connected to time server and device management  230  by a wired connection or a wireless connection via communications fabric  202  and communications unit  210 . Devices  260  may be devices depicted in the illustrative embodiments of  FIG. 3 ,  FIG. 4  and  FIG. 5 . Devices  260  may be activated and synchronized with time server and device management  230  to create absolute time  233  and start times  235  in the devices. Synchronization with time server and device management  230  may require a time stamp used for sending data to time server and device management  230  for equalization. Time stamp  221  may provide a time stamp for synchronization with time server and device management  230 . Start times from start times  235  may be acquired by devices  260  from time server and device management  230 . 
     Absolute time  233  may be set as a start time to the devices by start times  235 . In an alternate embodiment, start time may be absolute time  233  plus an amount of time determined to be after the multiple devices finish inquiring about time may be set as a start time. Acquisition of a start time may be used to insert the wait function. When an edge gateway, such as edge gateways  215  synchronizes with time server and management function  230 , a start time from start times  235  may be sent to edge gateways  215 . When multiple devices finish initialization, a start time may be sent to edge gateways  215 , according to a setting on time server and management  215 . When multiple devices enter a waiting state with a wait function, a start time may be sent to edge gateways  215  according to a setting on time server and management  230 . When a particular device finishes initialization, a start time may be sent to edge gateways  215  according to a setting on time server and device management  230 . Edge gateways  215  may receive a start time by polling. The start time may indicate absolute time released by the wait function of the device and be represented by year, month, day, hour, minute, and second, instead of time elapsed. 
     Devices  260  may have start points  245 . Devices  260  may be synchronized with timeserver and device management  230 , and then initialized by initialization function  224 . After initialization, devices  260  may be brought into a waiting state at start points  245 . Devices  260  brought into a waiting state may be reflected in waiting state  243  in data  240 . A waiting state may be indicated by a property file configured to receive notifications that devices  260  have entered a waiting state. Devices brought into waiting state may continue to inquire into time server and device management  230  for a time until a start time or an absolute time may be acquired from time server and device management  230  using start times  235  and absolute time  233 . When a start time from start times  235  may be acquired, devices  260  wait until the start time and then wait function or routine  248  is released. 
     Embedding a function such as wait( ) from wait function or routine  248  into a program may set one or more start points in start points  245  and may require a source code to be modified. Alternatively, a function from wait function or routine  248  may be embedded dynamically into an appropriate point of the program by setting one or more breakpoints in breakpoints  249  using graphical user interface (GUI)  222 . Wait function or routine  248  may be injected by injector  232  without modifying existing software. Alternatively, responsive to an automatic search for initialization function  224 , a wait function from wait function or routine  248  may automatically be injected by injector  230  into end points of initialization function  224 . 
     Communications unit  210 , in this example, provides for communication with other computers, data processing systems, and devices  260  via a network, such as network  102  in  FIG. 1 . Communications unit  210  may provide communications through the use of both physical and wireless communications links. The physical communications link may utilize, for example, a wire, cable, universal serial bus, or any other physical technology to establish a physical communications link for data processing system  200 . The wireless communications link may utilize, for example, shortwave, high frequency, ultra-high frequency, microwave, wireless fidelity (Wi-Fi), Bluetooth technology, global system for mobile communications (GSM), code division multiple access (CDMA), second-generation (2G), third-generation (3G), fourth-generation (4G), 4G Long Term Evolution (LTE), LTE Advanced, or any other wireless communication technology or standard to establish a wireless communications link for data processing system  200 . 
     Input/output unit  212  allows for the input and output of data with other devices that may be connected to data processing system  200 . For example, input/output unit  212  may provide a connection for user input through a keypad, a keyboard, a mouse, and/or some other suitable input device. Display  214  provides a mechanism to display information to a user and may include touch screen capabilities to allow the user to make on-screen selections through user interfaces or input data, for example. 
     Instructions for the operating system, applications, and/or programs may be located in storage devices  216 , which are in communication with processor unit  204  through communications fabric  202 . In this illustrative example, the instructions are in a functional form on persistent storage  208 . These instructions may be loaded into memory  206  for running by processor unit  204 . The processes of the different embodiments may be performed by processor unit  204  using computer-implemented instructions, which may be located in a memory, such as memory  206 . These program instructions are referred to as program code, computer usable program code, or computer readable program code that may be read and run by a processor in processor unit  204 . The program instructions, in the different embodiments, may be embodied on different physical computer readable storage devices, such as memory  206  or persistent storage  208 . 
     Program code  252  is located in a functional form on computer readable media  254  that is selectively removable and may be loaded onto or transferred to data processing system  200  for running by processor unit  204 . Program code  252  and computer readable media  254  form computer program product  256 . In one example, computer readable media  254  may be computer readable storage media  258  or computer readable signal media  250 . Computer readable storage media  258  may include, for example, an optical or magnetic disc that is inserted or placed into a drive or other device that is part of persistent storage  208  for transfer onto a storage device, such as a hard drive, that is part of persistent storage  208 . Computer readable storage media  258  also may take the form of a persistent storage, such as a hard drive, a thumb drive, or a flash memory that is connected to data processing system  200 . In some instances, computer readable storage media  258  may not be removable from data processing system  200 . 
     Alternatively, program code  252  may be transferred to data processing system  200  using computer readable signal media  250 . Computer readable signal media  250  may be, for example, a propagated data signal containing program code  252 . For example, computer readable signal media  250  may be an electro-magnetic signal, an optical signal, and/or any other suitable type of signal. These signals may be transmitted over communication links, such as wireless communication links, an optical fiber cable, a coaxial cable, a wire, and/or any other suitable type of communications link. In other words, the communications link and/or the connection may be physical or wireless in the illustrative examples. The computer readable media also may take the form of non-tangible media, such as communication links or wireless transmissions containing the program code. 
     In some illustrative embodiments, program code  252  may be downloaded over a network to persistent storage  208  from another device or data processing system through computer readable signal media  250  for use within data processing system  200 . For instance, program code stored in a computer readable storage media in a data processing system may be downloaded over a network from the data processing system to data processing system  200 . The data processing system providing program code  252  may be a server computer, a client computer, or some other device capable of storing and transmitting program code  252 . 
     The different components illustrated for data processing system  200  are not meant to provide architectural limitations to the manner in which different embodiments may be implemented. The different illustrative embodiments may be implemented in a data processing system including components in addition to, or in place of, those illustrated for data processing system  200 . Other components shown in  FIG. 2  can be varied from the illustrative examples shown. The different embodiments may be implemented using any hardware device or system capable of executing program code. As one example, data processing system  200  may include organic components integrated with inorganic components and/or may be comprised entirely of organic components excluding a human being. For example, a storage device may be comprised of an organic semiconductor. 
     As another example, a computer readable storage device in data processing system  200  is any hardware apparatus that may store data. Memory  206 , persistent storage  208 , and computer readable storage media  258  are examples of physical storage devices in a tangible form. 
     In another example, a bus system may be used to implement communications fabric  202  and may be comprised of one or more buses, such as a system bus or an input/output bus. Of course, the bus system may be implemented using any suitable type of architecture that provides for a transfer of data between different components or devices attached to the bus system. Additionally, a communications unit may include one or more devices used to transmit and receive data, such as a modem or a network adapter. Further, a memory may be, for example, memory  206  or a cache such as found in an interface and memory controller hub that may be present in communications fabric  202 . 
     Illustrative embodiments are capable of being implemented in conjunction with any type of computing environment now known or later developed. Cloud computing is a model of service delivery for enabling convenient, on-demand network access to a shared pool of configurable computing resources, such as, for example, networks, network bandwidth, servers, processing, memory, storage, applications, virtual machines, and services, which can be rapidly provisioned and released with minimal management effort or interaction with a provider of the service. This cloud model may include at least five characteristics, at least three service models, and at least four deployment models. 
     The characteristics may include, for example, on-demand self-service, broad network access, resource pooling, rapid elasticity, and measured service. On-demand self-service allows a cloud consumer to unilaterally provision computing capabilities, such as server time and network storage, as needed automatically without requiring human interaction with the service&#39;s provider. Broad network access provides for capabilities that are available over a network and accessed through standard mechanisms that promote use by heterogeneous thin or thick client platforms, such as, for example, mobile phones, laptops, and personal digital assistants. Resource pooling allows the provider&#39;s computing resources to be pooled to serve multiple consumers using a multi-tenant model, with different physical and virtual resources dynamically assigned and reassigned according to demand. There is a sense of location independence in that the consumer generally has no control or knowledge over the exact location of the provided resources, but may be able to specify a location at a higher level of abstraction, such as, for example, country, state, or data center. Rapid elasticity provides for capabilities that can be rapidly and elastically provisioned, in some cases automatically, to quickly scale out and rapidly released to quickly scale in. To the consumer, the capabilities available for provisioning often appear to be unlimited and can be purchased in any quantity at any time. Measured service allows cloud systems to automatically control and optimize resource use by leveraging a metering capability at some level of abstraction appropriate to the type of service, such as, for example, storage, processing, bandwidth, and active user accounts. Resource usage can be monitored, controlled, and reported providing transparency for both the provider and consumer of the utilized service. 
     Service models may include, for example, Software as a Service (SaaS), Platform as a Service (PaaS), and Infrastructure as a Service (IaaS). Software as a Service is the capability provided to the consumer to use the provider&#39;s applications running on a cloud infrastructure. The applications are accessible from various client devices through a thin client interface, such as a web browser (e.g., web-based e-mail). The consumer does not manage or control the underlying cloud infrastructure including network, servers, operating systems, storage, or even individual application capabilities, with the possible exception of limited user-specific application configuration settings. Platform as a Service is the capability provided to the consumer to deploy onto the cloud infrastructure consumer-created or acquired applications created using programming languages and tools supported by the provider. The consumer does not manage or control the underlying cloud infrastructure including networks, servers, operating systems, or storage, but has control over the deployed applications and possibly application hosting environment configurations. Infrastructure as a Service is the capability provided to the consumer to provision processing, storage, networks, and other fundamental computing resources where the consumer is able to deploy and run arbitrary software, which can include operating systems and applications. The consumer does not manage or control the underlying cloud infrastructure, but has control over operating systems, storage, deployed applications, and possibly limited control of select networking components, such as, for example, host firewalls. 
     Deployment models may include, for example, a private cloud, community cloud, public cloud, and hybrid cloud. A private cloud is a cloud infrastructure operated solely for an organization. The private cloud may be managed by the organization or a third party and may exist on-premises or off-premises. A community cloud is a cloud infrastructure shared by several organizations and supports a specific community that has shared concerns, such as, for example, mission, security requirements, policy, and compliance considerations. The community cloud may be managed by the organizations or a third party and may exist on-premises or off-premises. A public cloud is a cloud infrastructure made available to the general public or a large industry group and is owned by an organization selling cloud services. A hybrid cloud is a cloud infrastructure composed of two or more clouds, such as, for example, private, community, and public clouds, which remain as unique entities, but are bound together by standardized or proprietary technology that enables data and application portability, such as, for example, cloud bursting for load-balancing between clouds. 
     A cloud computing environment is service oriented with a focus on statelessness, low coupling, modularity, and semantic interoperability. At the heart of cloud computing is an infrastructure comprising a network of interconnected nodes. 
       FIG. 3  depicts a schematic illustrating configuration  300  for synchronizing multiple devices using edge gateways, an application server, and a time server and device management application in accordance with an illustrative embodiment. 
     Multiple devices comprise car data device  323 , navigation device  325 , and device  327 . Car data device  323 , navigation device  325 , and device  327  may be devices  260  in  FIG. 2 . Car data device  323  may be a device that obtains a vehicle speed, direction, travel distance and other desired vehicle information. Navigation device  325  may be a device to get longitude, latitude, map information and so on. Device  327  may be a health device, (for example to get heart rate of a driver), a drive recorder device, or some other device to get desired information. Device plugins  322 ,  324 , and  326  may be device plug in  234  in  FIG. 2 . Device plugin  322  changes a physical device to a logical device by providing for communication between plugin manager  321  and a physical device such as car data device  323 , navigation device  325  or device  327 . For example, device plugin  322  may change units in kilometers per hour to miles per hour or degrees to millidegrees. Plug-in device  322  may transform a data format from raw data from a device to XML data. Device plugin  322  may be configured for car data device  323 . Device plugin  324  may be configured for navigation device  325 . Device plugin  326  may be configured for device  327 . In an embodiment, plugin devices  322 ,  324 , and  326  may be configured for car data device  323 , navigation device  325 , and device  327 . 
     Plugin manager  321  may be a module to manage a logical device (a pair of device plugin and physical device). Plugin manager  321  may collect formatted and normalized data from some physical devices through the device plugins. Plugin manager may actuate psychical devices through device plugins such as plugin devices  322 ,  324 , and  326 . Plugin manager  321  may filter data and may also interpolate data. For example, plugin manager  321  may get data from device  321  every 500 milliseconds and may send averaged data every one second to time server and device management  310 . Plugin manager  321  may receive data from device  327  every one second, and may send approximated data that may be made by an interpolation algorithm every 500 milliseconds. Communication  318  may be communications unit  210  in  FIG. 2 . Communication  318  may be a module to communicate between edge gateway  320  and app server  350 . 
     Timer  312  may be a timer module that supports network timer protocol and be synchronized with correct time. Device manager  314  may be a module to manage a beginning time for each device. Generate trigger  316  may be a module to set a trigger and notify a trigger. Generate trigger  316  may be assigned a start time and may send a trigger to plugin manager  321 . Timer  312  may receive a correct time through plugin manager  321  and communication  318  from an external Network Time Protocol (NTP) server. ETP server may be data processing system  200  in  FIG. 2 . 
     Each device may get a correct time from timer  312 . Beginning time for each device may be set to generate trigger  316 . Generate trigger  316  may set a beginning time for each device to device manager  314 . Device manager  314  may get time from timer  312 . If it is the beginning time of the device, device manager  314  may notice it to generate trigger  316 . Generate trigger  316  may wake up each device. Synchronized data may be sent to app server  350  from plugin manager  321 . Edge gateway  330  and edge gateway  340  are similar to edge gateway  320 . App server  350  may provide communication  352  between edge gateway  320 , edge gateway  330  and edge gateway  340 . App server  350  may be data processing system  200  in  FIG. 2 . 
       FIG. 4  depicts a schematic illustrating configuration  400  for synchronizing multiple devices using edge gateways, an application server, and a time server and device management application illustrating a process in accordance with an illustrative embodiment. The illustrative embodiment of  FIG. 4  is similar to the illustrative embodiment of  FIG. 3 . In  FIG. 4 , timer server and device management  410  communicates directly with communication  428  of edge gateway  420 , communication  438  of edge gateway  430 , and communication  448  of edge gateway  440 . App server  450  communicates directly with communication  428  of edge gateway  420 , communication  438  of edge gateway  430 , and communication  448  of edge gateway  440 . Plugin manager  421  is similar to plugin manager  321  in  FIG. 2 . Device plugins  422 ,  424 , and  426  are similar to device plugins  322 ,  234 , and  326  in  FIG. 3 . Car data device  423  is similar to car data device  323  in  FIG. 3 . Navigation device  425  is similar to navigation device  325  in  FIG. 3 . Device  427  is similar to device  327  in  FIG. 3 . 
       FIG. 5  depicts a schematic illustrating configuration  500  for synchronizing multiple devices in an edge gateway in accordance with an illustrative embodiment. In an illustrative embodiment, synchronization may be performed in edge gateway  520 . Time and device management  510  may be placed in edge gateway  520  to allow device plugins  522 ,  524 , and  526  in edge gateway  520  to be synchronized directly with edge gateway  520 . In the configuration of  FIG. 5 , time and device management function  510  communicates directly with plugin manger  521  and is not connected to communication  528  of edge gateway  520  or to communication  552  of app server  550 . Timer  512  is similar to timer  312  in  FIG. 3 . Device manager  514  is similar to device manager  312  in  FIG. 3 . Generate trigger  516  is similar to generate trigger  316  in  FIG. 3 . Car data device  525  is similar to car data device  323  in  FIG. 3 . Navigation device  525  is similar to navigation device  325  in  FIG. 3 . Device  527  is similar to device  327  in  FIG. 3 . The configuration of  FIG. 5  may be used when there is no need for synchronization with multiple devices in multiple edge gateways. 
       FIG. 6  depicts an example of injection of a wait function in accordance with an illustrative embodiment. In this context, “hooking” means that an application&#39;s request for executing a function may be automatically redirected to the injected code so that some additional operations can be done before or after running an original function&#39;s code without modifying or recompiling a caller&#39;s module. Injector  602  may be a module that performs hooking in order to inject a wait function. Target process  610  may be a process having one or more target functions that may be hooked by injector  602 . 
     API hook  612  may be a module that consists of a new function for an intercepted original function. When target process  610  is hooked by injector  602 , a new function may be called instead of an original function. In an illustrative embodiment, if target process  610  has CreateFile API. CreateFile API is hooked by injector  602 , the original function, CreateFile API, may be replaced by MyCreateFile in API hook  612 . Once the hook and replacement is performed, MyCreateFile will be called instead of CreateFile. Injection may be performed dynamically by injector  602 . Injector  602  may call SuspendThread  620  to suspend all threads of target process  610 . VirtualAllocEx ( . . . ) (see  620 ) may allocate memory in target process  610 . Injector  602  may save a start address of the memory to variable “pMem.” 
     Injector  602  may write a full path of API hook  612  on the allocated memory. Injector  602  may call CreateRemoteThread  622  with an address of Load Library with pMem variable  606 . CreateRemoteThread  622 ) may call LoadLibrary with pMem variable  606  in target process  610  internally. LoadLibrary with pMem variable  606  may load API hook  612  in target process  610  and LoadLibrary with pMem variable  606  may be started internally. API hook  612  performs hooking in target process  610  internally. API hook  612  may replace any function in API hook  612 . For example, API Hook  612  may replace CreateFile to MyCreateFile. After injector  602  calls ResumeThread (see  622 ), all threads of target process  610  may resume. 
       FIG. 7  depicts another example of injection of a wait function in accordance with an illustrative embodiment. Conceptual diagrams of instruction codes stored in memory, comparing the original state before “hooking” with the modified state after “hooking” are depicted. For transferring from the original state to the hooking state, several bytes of code at the top of the function are replaced with other instructions so that the function call may be redirected to another function. Those original instructions are backed up in the virtual memory area so that the original function can be executed after finishing the redirected codes. API Hook DLL in hooking state  704  may be a dynamically-injected module which implements additional function codes for caller applications to execute. Original state  702  may be the state before enabling Wait ( ) function, and hooking state  704  may be the state after enabling it. In hooking state  704 , any application automatically calls the Wait( ) function in API Hook DLL in hooking state  704  after entering into start( ) function, without modifying or recompiling application code. 
     In original state  702 , when a caller—Target.exe—in the illustrative embodiment—calls function start( ), the central processing unit executes the instruction code at the function&#39;s entry point address (77d10d2) and returns to the caller after executing the final “ret” instruction. On the other hand, in hooking state  704 , when Target.exe calls function start( ) (see arrow line  1 ), the central processing unit executes the ‘jmp’ instruction indicating a jump to injected code (see arrow line  2 ) and then executes additional operations, Our Additional Code, and calls the “Wait( )” function. After executing Our Additional Code and Wait( ), the central processing unit calls the original function&#39;s code which has been backed up in virtual memory (see arrow line  3 ). The last instruction in virtual memory may be a ‘jmp’ instruction, which causes a jump to the remaining code in the original function (see arrow line  4 ) consequently completing the original function code. The final ‘ret’ instruction makes the central processing unit execute the remaining part of injected codes (see arrow line  5 ), which may be code to do nothing and return to the caller (see arrow line  6 ). 
     Code segment 77d10d2 may be an example of a memory address pointing to the start( ) function in target.exe of original state  702 . Target.exe may be a memory block containing instruction codes of function start( ). The code “ret” may be a final instruction of “start( )” function. Target.exe in original state  702  may be similar to target.exe in hooking state  704 , except for the first two instructions which have been replaced with other instructions so that the function call may be redirected to the code in API Hook DLL of hooking state  704 . Virtual memory in hooking state  704  stores instruction code at the top of an original function. Two instructions in original state  702  may be replaced with other instructions in hooking state  704 . Wait( ) function may cause the central processing unit to wait for all other devices to be synchronized. 
       FIG. 8  depicts a flowchart illustrating a process for synchronizing multiple devices in accordance with an illustrative embodiment. The use of the technique prevents differences in data that arise from lack of synchronization. The technique can be used not only for tests, but also for the actual synchronization of the multiple devices. Synchronization logic may be dynamically injected without software on the devices being modified, which does not require modification cost. As used herein “dynamically injected” means instruction codes in memory are modified while the application may be running so that the additional logic can be executed when the application operates that function. A synchronous point may be the memory address of a function which should be synchronously executed with other devices, and may be the address where wait( ) function may be placed. 
     Process  800  is for synchronously starting programs on multiple devices connected to a server start. A synchronous point of a program to be synchronously started is identified for each of a number of devices (Step  802 ). A wait function is dynamically injected into the synchronous point for each of the multiple devices (Step  804 ). 
     A start time is received from the server in response to the multiple devices entering a waiting state (Step  806 ). A determination may be made whether a start time for a device has arrived (Step  808 ). If a start time for the device has not arrived, process  800  returns to step  806 . Responsive to receiving a start time for a device, a program is synchronously started in response to the start time arriving for the device (Step  810 ). A determination is made as to whether all devices have been started (Step  812 ). If all devices have not been started, process  800  returns to step  802 . If all devices have been started, process  800  terminates. 
     In an embodiment, the start time received by one of the multiple devices may be different from the start time received by another one of the multiple devices. In an embodiment, a server may be provided with a function of a time server and each of the multiple devices may be synchronized with the time server. In an embodiment, time in the device may be corrected. In an embodiment, the start time may not be relative time but absolute time. In an embodiment, the wait function may be operated according to a sequence that waiting may be performed until the start time may be sent, the start time may be received from the server, and the start time may arrive. 
     The time server can be put not only on multiple edge gateways, but also on a single edge gateway to allow the multiple devices in the edge gateway to be synchronized. Delay activation of the devices can also be intentionally made as well as synchronization. 
       FIG. 9  depicts a flowchart illustrating a process for dynamically inserting a wait function in accordance with an illustrative embodiment. There may be several ways to insert the wait function. Wait functions may be embedded into source codes. A process, such as process  900  is displayed on a graphical user interface (Step  902 ). A point into which a wait function is inserted is shown on the graphical user interface (Step  904 ). Timing at which initialization is finished is automatically determined (Step  906 ). The wait function is dynamically injected into the part (Step  908 ). Thereafter, the process terminates. For example, when a thread class may be defined like Java and extended to implement the class, a start method generally bears an initialization part to dynamically inject the wait at the time of ending the method. 
       FIG. 10  depicts a flowchart of a process for dynamically releasing a wait function in accordance with an illustrative embodiment. Process  1000  starts. A start time is sent to the edge gateway according to the setting on the time server ( 1002 ). The edge gateway receives a start time. (Step  1004 ) A determination is made whether the time is the same as the start time (Step  1006 ). If not, process  1000  waits (Step  1010 ). If the time is the same as the start time, the wait function is released (Step  1008 ). At the start time, the wait function may be released. Release of the start time may cause all the devices to be synchronized. Thereafter, the process terminates. 
       FIG. 11  depicts a flowchart of a number of triggers for sending a start time in accordance with an illustrative embodiment. Process  1100  starts. A wait function is connected with a time server to perform synchronization with time (Step  1102 ). Wait functions in all devices enter the waiting state (Step  1104 ). A determination is made whether the plugin manager of the edge gateway has been informed that all devices have entered the wait state (step  1106 ). If the plugin manager of the edge gateway has been informed that all devices have entered the wait step, the start time may be sent (Step  1112 ). If not, a determination is made whether a time server has been informed that all devices have entered the waiting state (Step  1108 ). If the time server has been informed that all devices have entered the waiting state, process  1100  goes to step  1112 . If not, a determination is made whether the time server recognizes that the multiple devices have entered the waiting state, with the property file of the time server (Step  1110 ). If the time server recognizes that the multiple devices have entered the waiting state, with the property file of the time server, the process goes to step  1112 . Process  1100  determines whether the time is the same as the start time (Step  1114 ). If the time is the same as the start time, then the wait function may be released (Step  1116 ). If the time is not the same as the start time, process  1100  goes to step  1106 . After the wait function is released in step  1116 , process  1100  terminates thereafter. 
     The descriptions of the various embodiments of the present invention have been presented for purposes of illustration, but are not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiment. The terminology used herein was chosen to best explain the principles of the embodiment, the practical application or technical improvement over technologies found in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed here. 
     The flowchart and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function or functions. It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems that perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.