System and method using the same, information processing apparatus and method using the same, and storage medium

The present invention provides a system in which, via a web page provided using a web browser by a management server, a management screen provided by a network device can be accessed while the management server does not need to have a private IP address of the network device.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a technique with which a management server manages network devices over a network.

Description of the Related Art

In recent years, network device management systems have been used in which network devices located in LANs (Local Area Networks) are managed by one or more management servers connected to the network devices over the Internet. Such a management server can receive and accumulate information from network devices about the hardware and software configurations of the devices, the operation of the devices, and the occurrence of failures in the devices. The management server has portal screen functionality of providing the accumulated information to users in order to inform the users of the use statuses of and failure occurrence statuses in the devices.

Each network device, in turn, has the functionality of providing, via a web server for the device, a remote management screen in which device operation information is displayed to allow the user to modify settings. The user can connect to the remote management screen using a web browser installed in a client apparatus, such as a PC (Personal Computer), residing in the LAN in which the network device is located. To connect to the screen, the user needs to enter the network device's network address used in the private network (referred to as a private IP address) into a web browser.

Japanese Patent Application Laid-Open No. 2017-168140 discloses a method of providing access to a screen implemented in a network device. The network device is an image forming apparatus such as a printer, and the screen is used for performing a print process. The method in Japanese Patent Application Laid-Open No. 2017-168140 is similar to the above-described method of connecting to the remote management screen using the client apparatus in that access to functionality of a network device is provided. In Japanese Patent Application Laid-Open No. 2017-168140, the method for the user to access the network device from the client apparatus is described as a method involving the user himself/herself specifying a network address of the device.

Now, when the user attempts to access the above remote management screen, the task of checking the private IP address of the network device may be troublesome. For example, if many network devices are being managed, checking the private IP address of each device is demanding. In addition, the private IP address assigned to each network device may be periodically updated. The user then needs to check the latest private IP address each time the user desires to access the remote management screen, which is inefficient.

A possible way to solve the above inconvenience may be as follows. Each network device transmits the private IP address to the management server over the Internet. The management server records the received private IP address in association with the serial number of the network device (an ID unique to the device). The user can then access the device by accessing the management server using the web browser of the PC and by referring to the private IP address of the network device in a given web page.

However, nowadays it is desired not to transmit information that includes confidential or personal information from network devices to management servers over the Internet. In view of the trend of the times, transmitting the private IP address of the network device over the Internet is unpreferable. Avoiding the transmission of the private IP address to the management server, however, prevents the management server from providing the above-described functionality that enables the user to access the remote management screen of the network device.

SUMMARY OF THE INVENTION

A system of the present invention includes: an information processing apparatus connected to a network environment where a network device is located; and a management server managing the network device from outside the network environment without holding local address information used in the network environment where the network device is located. The management server includes a providing unit that provides page information, the page information including: a description for passing an identifier for identifying the network device being managed to an application executed in the information processing apparatus; and a page object associated with the description. The information processing apparatus includes, as functionality of the application: a search unit that performs a search process in the network environment if the page object is selected via a screen displayed based on the page information in a web browser executed in the information processing apparatus; and a presentation unit that, if a network device corresponding to the identifier passed from the web browser to the application in response to selecting the page object is found in the search process, presents information for accessing a management screen provided by the network device, the information being presented using local address information acquired from the network device corresponding to the identifier and found in the search process.

DESCRIPTION OF THE EMBODIMENTS

Exemplary embodiments for implementing the present invention will be described below with reference to the drawings.

The present invention proposes a method in which functionality of a network device is accessed while a management server that connects to the network device over the Internet to acquire operation information about the network device does not need to receive a local network address from the network device.

First Embodiment

First, a network system in a first embodiment will be described. The network system includes a management system (a management server100), and a client apparatus101and network devices102being managed by the management system.

FIG. 1illustrates a configuration in which the management server100connects, over the Internet103, to the client apparatus101and the network devices102located in a local network environment (a network104). In the embodiment, the management server100serving as the management system is illustrated as implemented by a single information processing apparatus. Alternatively, the management server100may be implemented by distributing its functionality among multiple information processing apparatuses. Further, a client apparatus105connects to the management server over the Internet103. Although the embodiment describes the network devices102as image forming apparatuses, this is exemplary and does not limit the application scope of the present invention.

The management server100is a server that centrally manages network devices102in network environments of many end users (customers who own the network devices). The management server100can centrally manage, over the Internet103, network devices102in multiple local networks.

The client apparatus101is an information processing apparatus such as a personal computer (PC), with which an end user who is an information device management worker connects to the management server100for checking the operation status of one or more network devices102. Operations performed with the client apparatus101include using a web browser or the like to refer to management information transmitted from each network device102to the management server100. The client apparatus101can also be used to receive an e-mail message sent when the management server100detects that each network device102is running out of a consumable item.

The network devices102are image forming apparatuses with printer, fax, and copy functionality. Each network device102can transmit management information, such as the number of printed sheets and the degrees of exhaustion of consumable items in the device, in association with the serial number of the device (a unique device ID) to the management server100.

Although not illustrated inFIG. 1for simplicity, multiple local networks104may exist in the Internet103. In the illustrated configuration, each network device102transmits the management information about the device directly to the management server100. In an alternative configuration, an intermediary agent apparatus may acquire the information about the network device102and transmit the information to the management server100. Multiple such agent apparatuses may be assigned to the respective network devices102, or a single agent apparatus may have capability to manage multiple network devices102in the local network104.

The client apparatus105is used by a worker of a sales company or a maintenance service to access the management server100over the Internet103. The operator, purpose of use, and location of the client apparatus105are different from those of the client apparatus101, but the hardware and software configurations of the client apparatus105are similar to those of the client apparatus101. Operations performed with the client apparatus105include registering, viewing, updating, and deleting the information about the network devices102in the management server100.

The hardware configuration of an information processing apparatus that implements any of the management server100, the client apparatus101, and the client apparatus105inFIG. 1will now be described.FIG. 2is a block diagram illustrating the internal structure of the information processing apparatus.

The information processing apparatus (any of the management server100and the client apparatuses101and105) includes a CPU200, a main memory201, an auxiliary memory (secondary memory)202, an input/output I/F (interface) unit203, and a communication I/F unit204. The CPU200is a unit that executes predetermined programs and instructs various sorts of control of the information processing apparatus. The main memory201is work memory used by the CPU200in executing programs and is implemented by RAM (Random Access Memory) or the like. The auxiliary memory202is a storage apparatus for permanently storing data and is implemented by an HDD (Hard Disk Drive) or an SSD (Solid State Drive). The auxiliary memory202also stores application programs and an OS (Operating System). Various programs stored in the auxiliary memory202are loaded into the main memory201when executed by the CPU200.

The input/output I/F unit203includes a unit having the functionality of receiving the user's operational inputs, and a unit having the functionality of presenting information to the user. Examples of the unit that receives operational inputs include a mouse and a keyboard. On the other hand, examples of the unit having the functionality of presenting information to the user include a monitor and a speaker.

The communication I/F unit204can receive data from and transmit data to external apparatuses. Through a predetermined protocol, the communication I/F unit204can provide various sorts of management information about the network devices102recorded in the auxiliary memory202to the outside. The protocol may be, for example, HTTP (Hypertext Transfer Protocol) or SNMP (Simple Network Management Protocol). Examples of the external apparatuses include an external memory such as an external HDD and USB memory, computers connected over a network, and other network devices.

The hardware configuration of the network devices102will now be described.FIG. 3is a block diagram illustrating the internal structure of each network device102. Details of a CPU300, a main memory301, and an auxiliary memory302are the same as the CPU200, the main memory201, and the auxiliary memory202of the information processing apparatus inFIG. 2, respectively, and therefore will not be described here.

A mechanics unit303represents mechanical components that implement functionality provided by the network device102. For example, if the network device102is an image forming apparatus, exemplary components of the mechanics unit303include a print unit and a scan unit, which perform image forming in response to the user's execution instruction such as a print or copy instruction. An input/output I/F unit304may be implemented, for example, by a panel capable of touch operations. A communication I/F unit305connects to the network104to enable communication with other devices.

The software configurations of the apparatuses illustrated inFIG. 1will now be described.FIG. 4is a functional block diagram of the apparatuses.

First, the software configuration of the management server100will be described. The management server100has a device information management unit401, a display control unit402, a resource management unit403, and a transmission and reception unit404. The device information management unit401manages, in a database, information about the network devices102being managed by the management server100. Details of the information about the network devices102being managed will be described below.

The display control unit402controls web page generation, such as generating an HTML file in response to a request from the client apparatus101or105. The resource management unit403controls providing an application file such as an installer in response to a request from the client apparatus101. The transmission and reception unit404has the functionality of communicating with other apparatuses over the Internet103.

The software configuration of the client apparatus101will now be described. A web browser411specifies a URI (Uniform Resource Identifier) to acquire a web page provided by the management server100or a network device102, interprets the acquired page, and displays the page on the screen.

A transmission and reception unit412can communicate with other apparatuses over the network104. An installer execution unit413is functionality provided by an operating system (OS) and is an execution engine that executes, under the user's instructions, an application installer received from the management server100. The installer installs a search program414according to the present invention into the client apparatus101. The search program414includes modules (a device search unit415, a setting information acquisition unit416, and a device information management unit417) to be described below.

The device search unit415searches for the network devices102residing in the local network104and acquires network address information about each network device102as a search result. The setting information acquisition unit416acquires the serial number, model information about each network device102and the like by querying the device based on the above network address. The device information management unit417maintains a list of the network devices102being managed. The above list of the network devices102being managed is generated by passing information about the list of the network devices102, managed in the management server100, to the client apparatus101according to a method to be described below.

The software configuration of each network device102will now be described. A transmission and reception unit421can communicate with other apparatuses over the network104. A remote management screen control unit422controls a remote management screen that provides, in response to a request from the client apparatus101, operation information about the network device102(such as the error state and the use status). Details of the remote management screen will be described below.

A device information management unit423manages information about the network device102. Examples of the information about the network device102include the network address of the device such as the IP address, and the serial number of the device. The information about the network device102may also include information about the amount of use by the user, such as the number of printed sheets in the printing apparatus, and information about the failure occurrence status and the lives of replaceable parts in the device. The information about the network device102may also include information stored in the device for the user's device use, such as an address book and document files. An input/output processing unit424enables the user to input and output information, and specifically represents software that controls the input/output I/F unit304such as a hardware panel.

The software configuration of the client apparatus105is the same as that of the client apparatus101and therefore will not be described here. A web browser431and a transmission and reception unit432of the client apparatus105correspond to the web browser411and the transmission and reception unit412of the client apparatus101, respectively.

FIG. 5illustrates a device information management table in the device information management unit401of the management server100. The network devices102are registered in the table by a maintenance worker of a service provider via the client apparatus105. In order for a network device102to be managed in the system, the network device102needs to be located in the user environment and also needs to be registered in the table.

A network device ID500stores an identifier for uniquely identifying each network device102being managed. A user organization ID501stores an identifier for uniquely identifying an organization to which the user of each network device102belongs. In the information stored in the management server100, a user can access only information about network devices102assigned a user organization ID501corresponding to the organization to which the user belongs.

A product name502stores a character string that indicates the model of each registered network device102. A status503stores information about the state of each network device102. Examples of the status503include the occurrence of an error and running out of a consumable item. The device information management unit401updates the information in the status503in response to receiving information related to the status503from the network device102over the Internet103. A registration date504shows the date on which the maintenance worker registered the information about each network device102in the device information management table.

FIG. 6illustrates a network device list screen600according to page information provided by the management server. Based on the device information management table in the device information management unit401, the display control unit402provides the screen by generating page information in a description language such as HTML (HyperText Markup Language). The screen is accessed by the user of the network devices102using the web browser411of the client apparatus101.

A network device ID601stores an identifier (such as the serial number) that uniquely identifies each network device102. A product name602stores information that identifies the model of each network device102. A remote management screen603is a column for placing a page object (for example, a link button605) for controlling connection to the remote management screen provided by each network device102. A status604stores information indicating the state of each network device102. Links605are URI links for transitioning to the remote management screens of the respective network devices. Each page object (link button605) is associated with a description included in the page information; the description is to execute a script that passes the device ID (the serial number), which is a parameter for identifying the network device being managed by the management server, to the search program executed in the client apparatus101.

If the user presses a link605, the search program414in the client apparatus101is started via the web browser411according to the description included in the page information and associated with the pressed object. The search program414performs the process of detecting the network devices102being managed in the local network104and transitioning to the remote management screen according to the detection result. Note that, for example, if the latest version of the search program414is not installed in the client apparatus101, pressing the link button605causes the client apparatus101to perform control such as installing or updating the program.

FIG. 7is a sequence diagram illustrating the details of operations of the apparatuses in displaying, in the web browser411of the client apparatus101, the remote management screen of a target network device102in the embodiment. The sequential process is started when the user operates the web browser411to request, from the management server100, a list of network devices being managed. In the embodiment, the web browser411can use multiple tabs to open multiple web pages. For convenience, a tab in which the user's initial operation is performed will be referred to as a first web browser411-1as distinguished from a second web browser411-2to be described below.

First, at S700, the first web browser411-1requests a device list screen from the management server100. At S701, based on the user organization ID of the accessing user, the management server100determines a list of network devices102that the user is allowed to view, and provides the above-described network device list screen600to the web browser411-1.

Then, in response to the user selecting, in the network device list, a link605corresponding to a network device for which the user desires access to the remote management screen, the process proceeds to S702. At S702, the web browser411-1executes the search program414if the search program414is already installed in the client apparatus101. If, however, the search program414is not installed in the client apparatus101, the web browser411-1requests the installer execution unit413provided by the OS to perform the process of installing the search program414. At this point, the web browser411-1provides, as a parameter, a link to an installer entity and the network device list, displayed on the above device list screen, to the installer execution unit413. Details of providing the parameter will be described below.

At S703, the installer execution unit413installs the search program414into the client apparatus101by executing an installer downloaded from the management server100. Rather than from the management server100, the search program414may also be downloaded from some other location such as an app store service provided by an OS vendor. Before the installation, the web browser411-1displays an application installation confirmation screen as shown inFIG. 10to ask the user whether to install the search program414. The installation confirmation screen will be described below.

If the search program414is already installed in the client apparatus101, the installation process is skipped. The web browser411-1specifies a required parameter and proceeds to the execution of the search program414.

If the user permits the installation, the installation is performed and then the search program414is executed. At this point, the installer execution unit413passes, as an execution parameter, the network device list acquired at S702as described above to the search program414.

At S704, the search program414records the received network device list in the auxiliary memory202so that the list can be referred to when the program is started next time. At S705, the search program414searches for the network devices102located in the local network104. At S706, IP address information is returned as a response from the target network device102located in the local network104and for which the user desires access to the remote management screen.

Regarding the search for the network devices102, the local network104may include not only the target network device102but also other network devices102. As such, at S707, the search program414also detects another network device102that is not the target. At S708, the search program414receives an IP address as a response from the other network device102.

AlthoughFIG. 7shows only one other network device, two or more other network devices may exist. In that case, S707and S708are repeated as required.

At S709, a request to acquire the network device ID is issued to each network device102detected. Here, the network device IDs of both the target network device102and the other network device102are to be acquired. At S710, the network devices102return the network device IDs. At S711, the search program414saves the network device ID information and the IP address information acquired at S706, S708, and S710, and generates URL (Uniform Resource Locator) links to the remote management screens.

At S712, based on the acquired IP address information about the network devices102, the search program414starts a web browser411-2and requests displaying the remote management screen. The web browser started here opens a tab different from the tab of the web browser411-1that has been displaying the device list screen. At S713, the web browser411-2requests the remote management screen from the target network device by specifying a URL that includes the IP address. Finally, at S714, the target network device102provides the remote management screen by transmitting resources constituting the requested screen to the web browser411-2.

Through the above process, the user can use the web browser411to identify the target network device102and access the remote management screen.

FIG. 8illustrates a device address management table in the device information management unit417of the search program414. A network device ID800stores items corresponding to items in the device information management table in the management server100. A network address801stores a private IP address set for each network device. Each private IP address is local address information locally used in the network environment (such as the LAN) in which the network device is located, and the information is set and managed by the customer himself/herself Although the private IP addresses inFIG. 8follow IPv4 as an exemplary protocol, any protocol that can identify the network devices102is applicable. The table is updated when the processing at S704and S711in the sequence inFIG. 7is performed. The search program414can use the table to find the private IP address of each network device102and provide access to the remote management screen of a specified network device102.

FIG. 9describes an exemplary manner in which the web browser411provides the link to the installer entity and the network device list as a parameter to the installer execution unit413as described for S702in the sequence inFIG. 7. One specific manner to provide a link to an installer displayable in a web browser is the ClickOnce technology provided by Microsoft Corporation. The embodiment describes that the system uses ClickOnce, although this does not limit the scope of the present invention.

As an example, the link901to “NE001” will be described. For the target network device, the network device ID “NE001” is specified as “TargetDevice.” For the other network devices, the network device IDs “NE002” and “NE003” are specified as “OtherDrive.” The search program414serving as a ClickOnce application receives the URL parameter via the installer execution unit413serving as a ClickOnce loader, and stores the parameter in the URL property upon startup. Subsequently, in the processing at S704, the search program414refers to the URL property and analyzes the data therein. The search program414then stores, in the device address management table, the information about the target network device ID and the information about the list of the other network device IDs acquired.

FIG. 10illustrates an installation confirmation screen1000displayed at S703inFIG. 7. The screen is displayed before the installer execution unit413installs the search program414into the client apparatus101. A description1001is a sentence indicating to the user that the purpose of the search program414is searching in a local network environment for network devices. An installation button1002is to be pressed when the user permits the installation of the search program414. Pressing the installation button1002causes the installer execution unit413to install the search program into the client apparatus101. A cancel button1003is to be pressed when the user rejects the installation of the search program414. Pressing the cancel button1003causes the installer execution unit413to stop the installation process.

FIG. 11is a flowchart illustrating a method in which the search program414installed in the client apparatus101provides the link to the remote management screen of the network device specified by the user. The operations in the flowchart are implemented by the cooperation of the device search unit415, the setting information acquisition unit416, and the device information management unit417in the search program414. The flowchart takes into account also the operations upon the second and subsequent startups of the search program414, rather than only the operations immediately after the installation of the search program414into the client apparatus101.

First, at S1100, the network device ID list is acquired as an input parameter in the manner illustrated inFIG. 9. The data passed as the parameter here is the device ID of the network device for which the user desires to view the remote management screen, and the device IDs of the other network devices. At S1101, it is determined whether a pair of the target network device ID and its corresponding IP address is stored in the device address management table. If so, the process proceeds to S1102; otherwise, the process proceeds to S1106.

At S1102, the electrical continuity of the target network device102is checked by specifying the IP address. At S1103, it is determined whether connection to the target network device102can be established and whether the device ID matches the value held in the device address management table. If so, the process proceeds to S1104; otherwise, the process proceeds to S1106.

At S1104, a URI link to the remote management screen is generated by specifying the IP address, and displayed on the screen. Details of the screen displayed here will be described below with reference toFIG. 12. At S1105, network devices102located in the local network104are searched for in case that the user desires to move to the remote management screens of other network devices. The process then proceeds to S1110.

If it is determined at S1101that the pair of the target device ID and the IP address is not held, network devices are searched for at S1106in order to provide the link to the remote management screen. The process then proceeds to S1107. This is also the case if it is determined at S1103that connection to the target device cannot be established or the device ID has been changed. At S1107, it is determined whether a network device102corresponding to the target network device ID is detected.

If a network device102corresponding to the target network device ID is detected at S1107, the process proceeds to S1108; otherwise, the process proceeds to S1109. At S1108, a link to the remote management screen is generated using the IP address of the network device searched for at S1106. Details of the screen displayed with the link will be described below with reference toFIG. 12. At S1109, a message indicating the nonexistence of the user-desired network device102is displayed. At S1110, pairs of the network device IDs and the IP addresses of all the network devices102searched for are stored in the device address management table. The process then terminates.

FIG. 12illustrates a link screen1200of the search program414, containing the link to the remote management screen. The screen is displayed at S1104and S1108of the flowchart inFIG. 11.

A message1201indicates whether the remote management screen is available. The message shows the result of the determination at S1103and S1107of whether the user-desired network device102supports the remote management screen. A network device ID1202stores the identifier that uniquely identifies the network device102. A product name1203indicates the product type of the network device102.

A remote management screen button1204provides access to the remote management screen using the private IP address acquired from the network device. If the user presses the remote management screen button1204, the processing at S712described above inFIG. 7is performed. The search program414starts the browser411-2by specifying the URL generated using the private IP address. The browser411-2accesses a web server of the network device corresponding to the private IP address and displays the remote management screen provided by the network device.

A button1205provides a list of devices supporting the remote management screen. If the user presses the button1205, the screen transitions to a screen to be described below inFIG. 13, which lists network devices supporting the remote management screen.

FIG. 13illustrates a supporting device list screen1300, provided by the search program414, for displaying the list of network devices supporting the remote management screen. The screen is generated based on the network device IDs800and the network addresses801stored in the device address management table. A network device ID1301and a product name1302are similar to the network device ID1202and the product name1203inFIG. 12, respectively. Link buttons1303are buttons for transitioning to the remote management screens of the respective network devices.

With the screen, the user can use the remote management screens of the network devices102other than the network device102that the user has originally specified on the screen provided by the management server100. In doing so, the user also does not need to access the management server100again.

FIG. 14is a schematic diagram of a remote management screen1400provided by a network device102. A network device information area1401indicates availability statuses, and the remaining amounts of consumable items. Menu buttons1402enable access to functionality provided by the network device102, such as settings, access to saved document files, and an address book.

The above embodiment has described the way in which the network devices102managed by the management server100residing outside the local network104are identified and then the remote management screen is accessed. An advantage of this way is the ability to access the remote management screen without transferring the network addresses of the devices to the outside of the local network104.

Second Embodiment

In the above first embodiment, the client apparatus101has been described as a PC. The present invention, however, is also applicable to the cases in which the client apparatus101is a mobile device such as a tablet or a smartphone. A second embodiment describes a method of providing the remote management screen to the user on the client apparatus101that is a mobile device.

The system configuration, hardware configuration, software configuration, and provided screens in the second embodiment are the same as in the above first embodiment and therefore will not be described here. Only what are different from the first embodiment will be described below with respect to the process sequence inFIG. 7and the process flow inFIG. 11.

If the client apparatus101is a mobile device, again, the search program414may be preinstalled in the mobile device. The description here assumes that the search program is preinstalled.

If the search program is not installed yet, the installer execution unit413detects the fact in the processing at S702inFIG. 7. The installer execution unit starts a store application and guides the user to install an appropriate native application.

The link buttons605in the network device list screen600provided by the management server100and displayed in the web browser need to be implemented as buttons for invoking the native application. One method of invoking a native application of a mobile device through a link button implemented in a web page in this manner is using the mechanism of the Web Share API.

The Web Share API (Application Programming Interface) is a technology disclosed by Google LLC. The technology enables sharing web page information by passing data from a web page to a native application (an intent) installed in an OS. The technology can be used in any mobile device having the Android OS. The mechanism is started with a tap operation on a button in the web page and can present sharer application candidates in menu form to a user.

In the second embodiment, the following description assumes that the mobile device has the Android OS and that the network device list screen600provided by the management server100uses the mechanism of the Web Share API.

FIG. 9in the above first embodiment illustrates the case in which the length of a character string sufficient for allowing the parameter to be transmitted is ensured. If, however, the client apparatus101is, e.g., a mobile device, the length of a character string sharable with native applications may be limited. The display control unit402therefore switches the network device list screen600according to the type of the client apparatus101, such as a PC or a mobile device. If the client apparatus101is a mobile device, only the network device ID of the network device102for which the user desires displaying the remote management screen is passed as the parameter.

The management server100includes, in the description corresponding to each page object (link button605) in the page information about the network device list screen600: a description including a function for implementing the Web Share API (navigator.share); and data to be shared with the native application. The Web Share API allows specifying the three items “Title,” “Text,” and “Url” as sharable objects. In the embodiment, the management server100stores, as the data to be shared, the network device ID in the form of a value of character string data type in the “Text” object, thereby providing the page information about the network device list screen600.

In this manner, even if the client apparatus101is a mobile device, the user can move from the screen provided by the management server100to the remote management screen of the network device102.

Other Embodiments

While exemplary embodiments of the present invention have been described above, the present invention is not limited to these embodiments. Rather, various variations and modifications may be made within the gist of the present invention.

According to examples of the present invention, a method can be provided in which, via a network-device-related website provided by a management system in the Internet and displayed in a web browser, a management screen provided by a network device is accessed while the management system does not need to have local information about the network device such as a private IP address.

The present invention is not limited to the above embodiments, but various modifications and variations may be made without departing from the spirit and scope of the present invention. The following claims are thus appended in order to make the scope of the present invention public.