JP4118566B2 - Network construction device for device integration - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a network construction apparatus for device integration that integrates and manages various household devices and personal devices by URL addresses.
[0002]
[Problems to be solved by the invention]
In future life, it is expected that more and more processors will be built in the surroundings, specifically, analog wireless circuits and various sensors will be integrated with the processor, and various computing functions will be integrated in the surroundings. Will be built into the environment. In particular, the ubiquitous computing environment where the computer is not located in one place as a special box called “computer” but distributed throughout the human living environment is a hardware From the point of view, it could be realized soon.
[0003]
The ubiquitous computing environment unconsciously supports human beings who are active in the real world, and it is necessary to recognize the environment in which the human is located. In such a ubiquitous computing environment, The number of built-in processors is expected to increase. This makes it possible to control various household devices, search various information, and operate the devices according to our preference and surrounding information. For example, an audiovisual device such as television would be connected by a standard high speed network such as IEEE1394. Also, lighting and air conditions in the room will be controlled by a mobile phone or PDA device over a wireless network, and a processor may be built into the furniture. Eventually these networks will be integrated by the home gateway.
[0004]
However, from the viewpoint of software, middleware components are necessary to integrate various household devices in order to improve life. Middleware is software that runs on a so-called OS (Operating System) and provides application software with more advanced and specific functions than OS, and has an intermediate character between OS and application software. However, building middleware components that will now be widely used is not easy. For example, Jini (registered trademark), which is a technical specification for connecting various devices over a network and providing functions to each other, as well as personal computers and peripheral devices in homes, AV devices, telephones, home appliances, etc. UPnP (Universal Plug and Play), which is a technical specification for connecting devices over a network and providing functions to each other, is well known as middleware, but devices that use these middleware are Few. On the other hand, the HTTP protocol is expected to be widely incorporated into various devices in the near future, and the cost of implementing the Internet protocol in current processors is extremely low. Therefore, most future devices will have a built-in HTTP server and will be able to access the device from anywhere on the Internet.
[0005]
Specifically, in the near future, the processor will include a hardware accelerator running the Internet protocol and will introduce a web server at a very low cost. The web server is built in various devices, and the surrounding real object includes a URL for linking information to the real object. These systems increase real objects or integrate the real and virtual worlds. There are also products that use web technology such as Emit Technology. In this way, it is expected that devices with built-in web servers will appear in the near future.
[0006]
The home computing environment may include various devices such as television with built-in web server, video cassette recorder, lighting and microwave oven. These devices can be controlled from any web browser or application program using the HTTP protocol. For example, a television with a built-in web server can be diagnosed by the vendor from the web server. Therefore, it is possible to easily manage home devices remotely. The interior lighting can be controlled from a web browser. This situation leads to the construction of an inexpensive home automation system.
[0007]
However, the current HTTP protocol uses directory services (systems that store and retrieve network resources and their attributes) and automatic configuration management (Automatic Configuration Management) necessary to create complex home computing environments. ) Cannot provide the necessary functions.
[0008]
Various home devices such as TV (television) and VCR (digital video camera) are connected to the home network, and all home networks exchange various information and control other devices from other devices Can be integrated over the Internet to do. Since a future network can connect an extremely large number of devices, these devices should be integrated as one device from the user's point of view. This type of integration can be very important in the near future as a huge amount of equipment is expected to be connected to the Internet.
[0009]
A computing environment in which these various devices are connected to each other is called the aforementioned ubiquitous computing environment. However, the traditional concept of ubiquitous computing environments is somewhat limited when compared to the Internet, and there are additional issues to consider when attempting to design an Internet scale ubiquitous computing environment. There is.
[0010]
Various networks and protocols have been proposed for each application domain. For example, various protocols such as the above-mentioned Jini and UPnP (Universal Plug and Play) have been proposed for connecting various devices without configuration before use. HAVi, another protocol, has been proposed for the connection of various home audio-visual equipment. On the other hand, various network systems such as ATM (Asynchronous Transfer Mode) network, IEEE1394, Bluetooth (registered trademark) known as wireless communication technology for portable information devices, and VIA have been developed to connect various devices. It has been. Also in research groups, PEN, networked surface and CLAN have been proposed to connect advanced equipment in the future.
[0011]
However, the various useful properties of these basic protocols and networks are hidden from the application if the IP layer is inserted into the network. For example, the plug-and-play function provided by Bluetooth and the network bandwidth preservation function provided by ATM are usually the IP layer (Note: Although several proposals have been made to extend the IP protocol guaranteed by QOS, The abstraction provided by this proposal is usually not available at the top layer of ATM (which does not provide all of the bandwidth saving capabilities of ATM). Some devices do not support (support) the IP layer for connecting to other devices and services. Furthermore, each device may assume different control protocols and data formats to communicate with each other. Therefore, new approaches need to realize network support for future home appliances.
[0012]
In the past, virtual overlay networks have been used to solve various problems related to the Internet. However, the idea of applying virtual overlay networks for the integration of networked home devices has been extended. Not in. That is, it is necessary to construct a customized virtual overlay network in order to obtain an Internet-scale ubiquitous computing environment in an organizational manner.
[0013]
Therefore, the present invention has functions similar to directory services and automatic configuration management necessary to create a complex home computing environment without modifying home devices having a web server. An object of the present invention is to provide a network construction device for device integration that can be integrated.
[0014]
[Means for Solving the Problems]
A network construction apparatus for device integration according to claim 1 of the present invention connects a gateway server to a network network connecting a terminal owned by a user and a device to be controlled with a built-in web server, When the gateway server automatically collects information on currently available devices and presents the contents to the terminal, a command for controlling the target device is transmitted from the terminal. A device access means for translating the URL contained in the command and accessing the target device with the URL, and a search means for periodically sending an inquiry message using the HTTP protocol to the network. When the inquiry message from the search means is received within the specified expiration date, its own information is returned to the search means, The search means registers the information in the database or updates the database, sends the inquiry message to the device within the expiration date specified in the information, and requests for discovery from the terminal The search means is configured to select a currently available device from the database using full text search technology.
[0015]
In this case, the functions necessary for integrating the devices in the network based on the HTTP protocol are provided in the gateway server as the automatic configuration management means and the device access means corresponding to the directory service. It becomes possible to construct a complex home computing environment without modifying home devices.
[0016]
In addition, a network construction device for device integration includes a state recognition device control means in the gateway server that enables control of the device using the HTTP protocol and changes its operation according to a user's situation. It is a thing.
[0017]
In this way, the construction of a ubiquitous computing environment based on the HTTP protocol can be achieved.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in order with reference to the accompanying drawings. 1 to 3 show a network construction apparatus for device integration according to a first embodiment of the present invention.
[0019]
Before describing the detailed configuration, the most important basic concept in the design of this system is to use home appliances with web servers without modification. A general-purpose household device having a web server cannot modify a web server owned by itself, but it is very difficult to standardize a new protocol. However, normal people don't know how a home network is formed, so to build a home computing environment, the automatic configuration management found in Jini and UpnP must be supported. Don't be.
[0020]
In a conventional web-based environment, the user has to know the URL of each device before accessing. However, since there is no directory service that finds the URL of the device that the user wants to access, it is not easy to know the URL. Also, automatic configuration management is required to register URLs for each device in the directory service.
[0021]
FIG. 1 shows the overall configuration of a system that proposes naming management capable of integrating household devices. 1 is a communication means for realizing the Internet, and 2 is a plurality of communication means connected to this communication means. It is a household device. Reference numeral 3 denotes an HTTP client used under the HTTP protocol, and specifically corresponds to a personal computer (personal computer) when using the Internet at home.
[0022]
The system here consists of two components. The first component is a device 2 that is incorporated into the web-based environment. This device 2 includes a web server and is connected to a communication means 1 for constructing an Internet network through a standard network such as IEEE802.11b, Bluetooth, IEEE1394, or Ethernet. The system proposed here does not assume the expansion of the web server in each device 2. Therefore, any general-purpose product including a web server can be connected to the communication means 1 and used.
[0023]
The second component is a gateway server 4 provided for managing the home device 2. The gateway server 4 plays the role of a directory service that provides a method for accessing the target device 2 and further has a function as automatic configuration management for maintaining and managing the devices 2 that are currently available.
[0024]
When the home net user shown in FIG. 1 wants to access the home device 2 in the room, he / she first contacts the gateway server 4 using the HTTP client 3. The gateway server 4 provides the user with information regarding the available devices 2 in the room. From the user's point of view, the user issues a request to control the device 1 using a URL (Uniform Resource Locator: “address” of information on the Internet) including the IP address of the gateway server 4. It seems to the user that any household device is directly connected to the gateway server 4. The gateway server 4 forwards the request to the appropriate device 2 according to the information gathered from the device 2 web server.
[0025]
Next, how to specify a URL for controlling each device 2 will be described. The ultimate goal here is to provide a URL-based interface for any application or device. Web browsers generally use the standard HTTP GET mechanism to present query requests, so that URIs (Uniform Resource Identifiers) are descriptions that point to the location of information resources on the Internet. Access a remote host that matches (partially specified part of) and receive a response from that URI, or present data to the URI via HTML using the standard HTTP POST mechanism Also receives a response from a URI in HTTP. The URL passed by the user is translated as shown below, and the request is forwarded to the target device 2.
[0026]
In the system shown in FIG. 1, a user can access one or more devices 2 through a gateway server 4 provided as a proxy server based on HTTP. However, even when the gateway address is known, it is difficult for the user to identify one of the optimal devices 2 from the devices 2. Therefore, a naming convention based on the URL for specifying and controlling the device 2 is performed here. Although this convention is defined in a standard URL, a URL-style path element can contain some additional information, following a syntax similar to BNF (Bacchus notation), as shown in FIG.
[0027]
Here, the character “ε” next to <path> :: = means an empty string having no character string, and <string> corresponds to a series of alphabets. The attribute of the character “?” Next to <search> :: = represents a query expression, and if the field describes the nature of the query (say, location or owner), a set of field values Yes, one value is a string or an integer. The attribute “!” Identifies the command if the field describes the nature of the command, and its value is a string or integer.
[0028]
According to the above arrangement, for example, it can be expressed as a URL description “http: //some.where.com.8080/CEIL-LIGHT/! Power = ON”. This URL description calls the gateway named some.where.com. Listening on port number 8080 with prior consent. The next "CELL-LIGHT" element specifies the light controlled under the gateway. The element “! Power = ON” sends a signal to the gateway and designates a special function named “power” with an ON value for each device 2. This URL is a request to turn on the lamp named "CELL-LIGHT".
[0029]
Another example is "http://some.where.com/?location=room1&?function=light/!power=ON".
[0030]
In this example, the element “? Location = room1” identifies a location called “room1” of a building or floor controlled under the gateway server 4. The element “? Function = light” identifies one of the optimal devices 2 that supports “light”, which is functionally named at the location of room1. And this URL is also a request to turn on the light named "light".
[0031]
In order to dynamically specify such an optimal device 2, the URL decided here can include a format of “$ (variable)”. “Variable” indicates a variable name whose value is a character string. These variables are associated with environment variables provided by a shell program or operating system (OS) executed on the gateway server 4. The concept of variables for URL-based notation is described by G. Voelker and B. Bershad in “Mobisaik: Information System for Mobile Wireless Computing Environments (Workshop Proceedings in Mobile Computing Systems and Applications, 1994 IEEE Computer Society) ) "Was originally suggested by the method based on dynamic URLs. The dynamic URL variable must always be related to the environment variable provided by the shell program or operating system (OS) running on the user's computer (HTTP client 3). The proposed variables are interpreted dynamically by the gateway server 4.
[0032]
For example, consider an expanded URL that includes the above variable described as "http://some.where.com/$(LIGHT)/!power=ON".
[0033]
Here, the element “$ (LIGHT)” is one variable for specifying the electric light. When the variable of “LIGHT” maintained in the gateway server 4 is CELL-LIGHT that identifies the lamp mounted on the ceiling, the above URL is “http://some.where.com/CEIL Interpreted as -LIGHT /! Power = ON ". If a new light is installed in the room, the operating system (OS) may update the value of the "LIGHT" environment variable, which is considered one of the best in the current environment. Therefore, the movement of objects can be dynamically adapted to the current environment.
[0034]
Next, a mechanism for accessing the device 2, that is, a directory service will be described. The directory service in the present embodiment is to provide information on the currently available home device 2 connected to the communication means 1. It also provides a method for accessing the device. One of the major problems in web-based home computing is how to know the URL of the device 2 that the user wants to control. At that time, the gateway server 4 may return an HTML page including a URL for controlling the device 2 to the browser held by the user in the HTTP client 3. However, since it is not easy to access the device 2 from a program held by the user's HTTP client 3, this method is not desirable. Therefore, the system of the present embodiment provides a mechanism that makes it appear as if the device 2 is directly connected to the gateway server 4 from the user. This means that the HTTP client 3 on the user side needs to know the host name of the gateway server 4 and the name of the device 2.
[0035]
This method by this system can control the device 2 in the user's own home from any location on the Internet via the communication means 1 without knowing the IP address of each device 2. Therefore, it is not necessary to assume that the user knows the IP address or the host name of each device 2 in advance. Here, it is not necessary to consider the use of the latest dynamic DNS (Domain Name System: a system that associates host names and IP addresses on the Internet). DNS updates require the introduction of a DNS server in every home, which is impractical because the DNS installation requires a lot of knowledge about the Internet. Further, the system method here does not require the user's HTTP client 3 to directly access the device 2. In this way, the gateway server 4 can verify the confirmation of any request. Therefore, our approach also improves the security of traditional web-based home computing.
[0036]
The gateway server 4 includes a database storage unit that stores a map database constructed by a web robot (collecting data by automatically visiting the web server included in the device 2), which will be described later. When the request is received, the file part of the URL is examined and the command part is removed. The database is then searched by the remaining URL fields. The database returns a new URL, and the command part removed in the previous step is concatenated. The target device 2 is then accessed using that URL.
[0037]
This technique is called URL rewriting. For example, consider the URL "http://www.gw.tatsuo.tokyo.jp/TV/!channel=10/". This URL means "I want to set my home TV channel to 10." Since the IP address of the TV in the house is 123.5.10.10 by searching the database owned by the gateway server 4, the URL is changed to “http://123.5.10.10/!channel=10/ "Translate to and rewrite. This means that if the gateway server 4 has information for associating the home device 2 with the IP address, the user does not need to know the actual IP address.
[0038]
All devices 2 were not expected to become complex and active due to their limited processing power, storage capacity, bandwidth and power. Therefore, the software built in each device 2 must be as small and simplified as possible. However, existing management techniques for devices 2 such as UpnP and Jini are extremely heavy in terms of the need for storage capacity and computational power and cannot be used with most devices. Therefore, here we need a lightweight mechanism that can discover devices with low capabilities. In this method, a search means such as such a mechanism, that is, a web search engine (a Web site that can search information published on the Internet using a keyword or the like) is introduced into the gateway server 4. This engine maintains and manages a database of information collected from each device 2 and can discover related devices that the user needs through web search technology.
[0039]
Each web search engine records the unique identifier and operating time of the device 2 and periodically sends HTTP GET requests to all possible addresses on the sub-network at specific intervals to update its index. . When receiving a request from the gateway server 4, the device 2 replies with its own two profiles, an expiration date and an available command name formed in a format based on the URL detailed here. If any response is received from the device 2 while the engine of the gateway server 4 is operating, the engine deletes the registration of the device having no response from the database. Furthermore, this approach allows one or more engines to operate on the network. Engines can be connected to each other in a so-called peer-to-peer approach. Each engine provides an indexed query interface for the collected information, and can collect information from other engines and increase its own index updates.
[0040]
This mechanism can automatically incorporate the device 2 in a plug-and-play manner like Jini and UpnP. Considering the work of installation in the device 2 newly connected to the network or reinstallation in the registered device 2 to be reactivated, each engine periodically sends an HTTP-based inquiry message to the network it covers. Since it sends a lot, the device 2 receives a message from the engine within a given interval and returns its information to the engine. The engine then registers the information in its database or updates the database and then sends an inquiry message to the device 2 with the expiration date specified in the information. Upon receiving a discovery request from a user or other host, the engine selects the appropriate equipment from the database using the full text search technology used in current web search engines. Therefore, this mechanism can easily and naturally operate within HTTP. Since each engine can trust the management and discovery of the device 2, the device 2 can be treated as a stateless HTTP.
[0041]
One of the problems in the current architecture (basic design concept) is how to know the URL of each device 2. If the user wants to control the target device 2 from the HTTP client 3, he must know the syntax of the URL. In a future computing environment, it is possible to attach an electrical tag containing information on how to control the device 2. For example, you can attach a bar code that signifies lighting. The barcode is read when lighting is turned on by the personal device. The URL may be retrieved from the application by receiving a beacon that includes the URL, or RFID (Radio Frequency identification) may be used instead of the barcode.
[0042]
The solution here is to use a personal device to find the URL. This personal device can read barcodes including URLs and receive beacons. When the personal device reads the barcode, the ID is transferred to the barcode management means, ie, the barcode manager, in the gateway server 4. The bar code manager converts the received ID into an actual URL and sends a command to the target device 2. If the personal device receives a beacon, the URL in the beacon is transferred to the gateway server 4. By this method, when the system is used, various devices 2 can be easily controlled.
[0043]
Next, an example in which the apparatus configuration in FIG. 1 is developed will be described with reference to FIG. Here, one scenario shows how the system works. In the scenario, the user has a PDA device (Personal Digital Assistance) 11 as a remote control means for the device 2, and there are three devices 2 in the house, that is, here. A television 12 corresponding to an audiovisual apparatus, a microwave oven 13 corresponding to a household electrical appliance, and a light 13 as an illumination unit are connected to the communication unit 1 that constructs a home network. All of these devices 2 have built-in web servers, and the gateway server 4 collects information on the currently available devices 2 using a program that executes the web robot means as described above. For example, the television 12 returns information with a URL for accessing the web server, and the gateway server 4 stores the information in its own database.
[0044]
When the PDA device 11 activates and opens a web browser which is a Web page browsing means, the first HTTP GET request is found by the gateway web server 4. The web browser of the PDA device 11 returns an HTML page including a list of devices 2 currently available in the house via the wireless access point 15 on the Internet. The HTML page is automatically generated by the gateway server 4 using information collected by a program that executes the web robot means.
[0045]
Suppose that a user issues a command to turn on TV or television 12. The web browser of the PDA device 11 sends a GET command “http://www.myhome.net/TV/!power=on/”. The URL is “http://tv.myhome.net.tokyo.jp/!power=on/” (by G. Voelker and B. Bershad, “Mobisaik: Information system for mobile wireless computing environments (mobile computing Translation of the workshop in the video system and applications, IEEE Computer Society, 1994)) and transfer the command to the Television 12 web server. In this example, “www.myhome.net” is translated as “www.tatsuo.tokyo.jp” according to the context information of the user. This means that the user can access the television 12 of his / her home without knowing the IP address or host name of the gateway server 4 in his / her home. Moreover, this address is automatically retrieved by the system. “Http://www.tatsuo.tokyo.jp/TV/” is translated to “http://tv.tatsuo.tokyo.jp/”. This means that the user does not need to know the actual IP address or host name in his / her television 12. Finally, when the television 12 web server receives the command, the web server turns on the television 12 power switch.
[0046]
This technique enables control of the device 2 whose position is recognized, as will be described below. When a user connects his device (eg PDA device 11) to the Internet, all packets will be forwarded to the nearest router. The gateway server 4 runs on the router and any HTTP request is retrieved by the gateway server 4. The gateway server 4 may return a page on the browser of the PDA device 11 when the first HTTP is searched. Since the nearest gateway server 4 returns the page, the returned page is customized according to the position of the gateway server 4. This means that the user knows the device 2 that is currently available near him. For example, in the scenario described above, the available device 2 that is familiar to the user can be displayed on the browser of the PDA device 11. By using a plurality of gateway servers 4 in the house, it becomes possible to adapt the behavior of the user according to his / her location.
[0047]
The system here is desired as a base for realizing surrounding display or "Calm Technology". For example, assume that the URL that controls the television 12 is clicked. When the user sends an HTTP POST request for controlling the television 12 to the gateway server 4, the gateway server 4 may return a page including an IMG tag including a URL indicating that another light 14 should be turned on. Thus, the light 14 is automatically turned on by the URL in the IMG tag. This is an example of the surrounding display, and the system in this embodiment is very attractive as an experimental basis for ubiquitous computing research.
[0048]
In the future, this system will be rewritten to access the VCN server (Visitor And Community Network System: a server that includes software that can easily perform user-based service allocation, Internet-based billing systems, security / authentication services). Have been considered for the plan. The user accesses the proxy VCN server on the gateway server 4. The proxy VCN server forwards all packets towards the target VCN server running on a computer. This approach can provide a flexible way of providing information in a ubiquitous computing environment.
[0049]
The system is also considered for middleware components that connect Jini, UpnP and HAVi using a virtual overlay network. Since the system is based on the HTTP protocol for connecting these middleware components, it can be used to connect the system to Jini, UPnP and HAVi without modifying the middleware.
[0050]
Thus, in this embodiment, a new configuration of home computing has been described. This arrangement is based on a web system, in which various household devices 2 are integrated in a flexible way. The advantage of this method is that it is possible to provide directory management such as Jini and UPnP and automatic configuration management, but does not assume that the web server built in the device 2 is modified. Thus, the system of the present embodiment can be integrated with general-purpose household devices that have built-in web servers that will become very popular in the near future. Therefore, the configuration here can be used more smoothly than other technologies like Jini, UPnP and HAVi.
[0051]
As described above, in this embodiment, the communication means 1 for constructing a network that connects a terminal (HTTP client 3 or PDA device 11) owned by a user and a device 2 to be controlled with a built-in web server. The gateway server 4 is connected, and the gateway server 4 automatically collects information on the devices 2 that are currently available, and presents the contents to the terminal. When a command for controlling the device 2 is transmitted, device access means as a directory service for translating the URL included in the command and accessing the target device 2 with the URL is provided.
[0052]
In this way, the gateway server 4 has functions necessary for integrating the devices 2 in the network based on the HTTP protocol as automatic configuration management means and device access means corresponding to a directory service. A complicated home computing environment can be constructed without modifying the home device 2 having a web server.
[0053]
Furthermore, in this embodiment, the device 2 can be controlled using the HTTP protocol, and the situation recognition (“context-aware”) device control means for changing the operation according to the user's situation is provided as a gateway server. 4 is preferably provided. In this way, the construction of a ubiquitous computing environment based on the HTTP protocol can be achieved.
[0054]
Next, a second embodiment of the present invention will be described with reference to FIGS. Here, an embodiment in which deployment to a virtual overlay network is taken as an example is described in detail.
[0055]
Before the description of the embodiment, the overlay network here can be defined as a configuration in which the basic network included therein is used to support several upper networks, and the virtual overlay network is defined as Provide a sufficient set of basic properties to realize. The virtual overlay network extends the basic characteristics of the overlay network by adding a software layer to provide new abstract characteristics. Implementing that property on behalf of the user is customized for each application. This idea is similar to the active network in "A Survey Of Active Network" proposed by D. Tennenhouse and others in "IEEE Communication Magazine Vol.35, No.1" in 1997. Allows network customization, so application-specific code can be injected without modifying existing characteristics provided by the network, while virtual overlay networks are suitable for each application Add new abstract properties, do not extend existing networks, virtual overlay networks are more practical and easily customized for each application because they do not require modification of existing network infrastructure.
[0056]
Here, as shown in FIG. 4, a virtual overlay network 22 is defined as a network constructed on an existing network 21 such as the Internet. In the virtual overlay network 22, a number of application level gateways 23 are installed in the network 22 and connected by some network protocol such as the IP protocol. The role of the application level gateway 23 is to pass messages to the destination. Also, each message and protocol may be translated according to various requirements presented by the environment and the user. The application level gateway 23 can be thought of as a router device of the virtual overlay network 22. This gateway 23 is usually connected by the Internet, but the underlying data link network can be used directly if it is necessary to satisfy special QOS requirements between application level gateways 23.
[0057]
The virtual overlay network 22 will solve a wide range of problems that the Internet currently has. For example, the existing Internet uses FQDNs (fully qualified domain names) and IP addresses, but application-specific naming (naming) to employ message routing (optimal route selection). ). In addition, the connection between the application level gateways 23 directly uses the original network 21 or is configured in the application level gateway 23.
By carefully selecting (configuration), it is made to conform to each QOS requirement between gateways 23. On the other hand, it is very difficult to realize QOS guarantee between terminals on the Internet. By selecting the function of the application level gateway 23, the virtual overlay network 22 can be customized for each application. Experiments in building mobility support suggest that solutions to achieve high-level functionality should be customized for each application.
[0058]
The concept of virtual overlay network 22 is not new. Several proposals regarding the construction of a virtual overlay network 22 have been known for each application. For example, Inktomi's 2000 technical report “The Inktomi Overlay Solution for streaming Media Broadcasts” has proposed a virtual overlay network for multicast continuous media data such as video and audio. Also, "Overcast: Reliable Multicasting with an Overlay Network" by J. Jannotti, DKGifford, KLJohnson, MFKaashoek, JWO'Toole Jr. "The Prototype Embedded Network (PEN)" by Jones, A. Hopper (AT & T Laboratories, Cambridge, Technical Report, No. 15 2000) proposes a virtual overlay network for reliable multicasting. I came. In "Herald: Achieving a Global Event Notification Service" by LFCabrera, MBJones, M. Theimer (8th Workshop Bulletin on the Operating Systems Hot Topics in 2001), a virtual event for global event services Overlay networks have been proposed. In addition, in the "Technology Challenges for Virtual Overlay Networks" by KPBirman, the 2000 IEEE Workshop Bulletin on 2000 Information Assurance and Guarantee, the router partition used to divide the resources for each virtual overlay network Mechanisms have been proposed. This solution does not comprehensively satisfy all Internet requirements, but is sufficient to solve the problem of each domain.
[0059]
In the conventional network, the concept of the virtual overlay network has been partially adopted. For example, Mbone, one of the experimental networks built to make multicast, which is a technology for efficiently distributing data on the network, available on the Internet, and multicast capability on the current Internet An IP network has been constructed, and 6Bone has been used to develop the current IPv6 network on the Internet. In addition, domain naming systems and web caching systems are also considered virtual overlay networks, solving various problems in application-specific ways.
[0060]
These known proposals have greatly increased extensibility by adopting the concept of virtual overlay networks, but these proposals do not directly use traditional underlying data link networks and do not use protocols or messages. The translation of is obviously not used. In that respect, the system in this embodiment makes an effort to make full use of the concept of a virtual overlay network.
[0061]
Developing a virtual overlay network customized for each application in a systematic way is one of the most important objectives. However, the achievement of this goal can be determined from many previous experiences. Here, the construction of a virtual overlay network for integrating networked home devices will be described. For example, Jini, UpnP, HAVi, and SOAP (Simple Object Access Protocol: a protocol for calling data and services in other computers) are provided for controlling various household devices. A client device cannot control a home device if it does not support all of these protocols. However, supporting many protocols is impractical because it requires large storage capacity. Also, if new protocols are proposed for future home devices, new software must be added to the client devices.
[0062]
The virtual overlay network 22 here solves this problem by converting the protocol supported by the client device to the protocol supported by the home device. This conversion is performed by each application level gateway 23 according to the characteristics of the device and the network.
[0063]
Next, the effect of the virtual overlay network for integrating networked home devices will be described in detail. The ultimate goal to motivate the design of virtual overlay networks is to provide application-specific abstractions for each home device located on a heterogeneous network such as IEEE1394, Bluetooth, or the Internet. . Here, we explain the design and use of the current prototype virtual overlay network. First, design issues and an overview of our system are presented, followed by some of the components used so far. Finally, some problems with the current prototype system are explained.
[0064]
End-to-end discussion is the principle of system design for the Internet. In other words, complex network functions are likely to be pushed to network terminals. But the entire edge of the current Internet is not a complex computer. Because some of them are designed only for their own special purpose, such as home appliances, built-in computers and PDA devices, for example, they are not standard Internet protocols. It cannot be processed. Therefore, a richer network than such uncomplicated terminals should be supported and improved inside the network, even if there are terminals and sub-networks are not prepared for the Internet, all terminals And provide a seamless situation for sub-networks. The framework of the virtual overlay network here supports the addition of the following functions.
(1) The virtual overlay network skeleton is built around a new naming system. Rather than obeying attributes such as hard-coding hostnames into addresses, we think that devices should be examined according to intended information such as functional and physical location. In fact, some devices that do not support TCP / IP cannot have a unique address that can be used in the Internet, but are included by other servers that can connect directly to the device, and other servers. Need to be confirmed through.
(2) Web-based computing is performed through HTTP and is widely used in the current Internet. HTTP is a protocol that supports the World Wide Web (www), and by definition, any web browser can communicate using HTTP. This communication is generated by browsers that use URLs that conform to established naming conventions. Here, the virtual overlay network not only allows easy access from a web browser and control of various household devices, but also allows the devices to communicate with each other and cooperate.
(3) Some household devices are often managed under existing service discovery systems that manage devices and services such as Jini and UPnP. Such systems have been proposed to facilitate dynamic collaboration within devices / services with minimal management and human intervention. In order to support this ad hoc collaboration, there should be a means of announcing its presence to the network, so that nearby services can be discovered and accessed. The virtual overlay network skeleton provides a unified view not only for each device, but also for the existing management of each device.
(4) The virtual overlay network skeleton should make extensive use of transcoding to transform the data in the network. This is because home appliances often have significant limitations on computer resources such as processors and input / output devices. Some home appliances may not be able to directly process large amounts of data received from and sent to the network without any help in transcoding data from external systems.
[0065]
The skeleton of the virtual overlay network 22 in this embodiment is composed of a home device / service 24 and an application level gateway 23, but some of the home devices 24 are just application specific devices. Some of them don't support TCP / IP. Therefore, the application-level gateway 23 needs to functionally include protocol translation conversion means from the protocol specific to the device 24 to HTTP (or vice versa). Here, each application level gateway 23 is accepted as an HTTP-based proxy server. It accepts a control protocol for home appliance 24 based on HTTP and translates it into a protocol specific to appliance 24. Furthermore, it is proposed to use the gateway 23 as an access point to the Internet from a protocol specific to the device 24. The gateway 23 is provided with a translation service means for translating from HTTP to a command corresponding to the target device 24. The gateway 23 also exports a wide range of session interfaces for various devices from or to the Internet.
[0066]
The application level gateway 23 should support application-specific services such as naming, transcoding and packet forwarding for various devices, and is therefore scalable to the gateway 23. Introduce means to make The application level gateway 23 consists of two layers. The upper layer consists of functions to satisfy HTTP requests and various modules, which provide logic to perform web-based tasks such as validation and device control. This modular approach can incorporate additional modules to extend the functionality as the gateway 23. The lower layers access the actual equipment and use a framework to support each service.
[0067]
Another point to consider here is the controller of the device 24. This controller sends a control request for the device 24 based on HTTP to the gateway 23. A conventional web browser is used for the controller, but new functionality can be provided by making some modifications to the browser.
[0068]
Next, the example which actualized the said structure using two scenarios is demonstrated. The first scenario is accessing home devices from a web browser, and the second example is connecting two home networks that use different protocols. And the ultimate goal is to provide a URL-based interface to any application or device, but currently all network devices cannot be converted to HTTP services. Instead, each application level gateway controls one or more devices through their special network with a translation service from a URL-based representation to a corresponding command designed for the device. In general, a web browser accesses a remote host that matches a URI by using a standard HTTP GET mechanism to present a query request and receives a response from that URI, or a standard HTTP The POST mechanism is used to present data to the URI through the HTML format, and a response is received from the URI in HTTP. When the gateway 23 ends communication with the device 24, the end data is returned to the browser.
[0069]
The specific URL description is the same as that in the first embodiment, and the description thereof is omitted.
[0070]
The skeleton of the virtual overlay network 22 consists of three elements: an application level gateway 23, a terminal controller, and equipment / services. Equipment / services are application specific and will not be discussed here. In the following, the application level gateway 23 and controller will be described.
[0071]
As shown in FIG. 5, the application-level gateway 23 operates as a gateway between a device-specific network (home network) and the Internet. As described above, the application level gateway 23 bridges between the control method based on HTTP and various middleware control methods.
[0072]
The application level gateway 23 consists of four components. The first component executes a home network protocol such as HAVi, Jini or UPnP, which operates as a home network device. For example, if the component implements the Jini protocol, the component operates as a Jini device. The second component runs the HTTP protocol, and this component acts as a web server.
[0073]
The third component performs protocol translation, and this translation means converts between the HTTP processing as described above and a special home network protocol. For example, the HAVi translation means performs conversion from the HTTP protocol to the HAVi protocol and vice versa. In addition, Jini translation and UpnP translation will also be performed in the current prototype.
[0074]
The last component is registration management means. This registration management means can be accessed by an HTTP protocol from a web browser or a home network protocol from a device using the protocol. If a device 24 on the home network 22 is accessed from outside the home network 22, the name of the device 24 should be registered with the application level gateway 23. The name is registered via either the HTTP protocol or the home network protocol. After registration, a pseudo home network device is created in the application level gateway 23. The pseudo device registers its name in the automatic verification service. The role of the pseudo device is to convert control commands sent on the home network 22 to the HTTP protocol.
[0075]
Next, the startup procedure will be described. When the application-level gateway 23 starts up (begins), it tries to enter the surrounding network. Using the method provided by the protocol specific middleware used in this network, it is investigated which device (device) or which service is available. For example, in a Jini network, the gateway 23 will use Jini's matching service. The results accumulated by this survey are accumulated in a database that records attributes used by the home network protocol and corresponding commands used in HTTP-based methods.
[0076]
If the application-level gateway 23 receives an HTTP-based command from the Internet 21, it parses the command by referring to its internal database and determines which command should be sent to which command. Once determined, apply the necessary protocol translations and send out the corresponding middleware specific commands. On the other hand, the pseudo device created by the gateway 23 by the registration management means operates as a network device unique to the device 24. As a result, the device on the network 22 side specific to the application can control the device on the Internet 21 side of the gateway 23. In this way, the gateway 23 appears to provide the functions or services that are actually provided by the devices on the Internet 21 side to the devices in the home network 22.
[0077]
The application-level gateway 23 provides a control interface as an HTTP server, and any application-specific network device can be controlled using an HTTP-based control protocol. Therefore, it accepts the use of an existing web browser for controller 25. In recent years, web browsers have been built into PDAs, mobile phones and digital TV sets, not to mention PCs. All of these devices can be used by the application level gateway 23 to control other devices. When a wide area browser is used as the controller 25 as described above, the gateway 23 must generate a web page that includes a command button linked to each command it will accept. On the other hand, if controller 25 is built to generate its own unique HTTP-based commands, it has certain advantages over a wide range of browsers in terms of customization or adaptability to the home network environment. Will have.
[0078]
Next, how to connect several home networks providing different home network protocols using the virtual overlay network will be described. As shown in FIG. 5, it is assumed here that there are three home networks 22 (22A to 22C) connected to the Internet 21 through gateways 23 at respective application levels. Each home network 22 has their gateways 23 (23A to 23C) "http://any.where.net", "http://my.home.net", "http://foo.bar", respectively. It uses the URL ".net" and uses application-specific protocols: UpnP, HAVi and Jini.
[0079]
As an example, let us assume a case where it is desired to control the VCR device 31 on the HAVi network 22A from the PDA 32 to the UPnP network 22C. In the HAVi network 22A, the VCR device 31 is registered as “VCR”, and the application level gateway 23A (HAVi, ApGW) is registered as “apgw” in the HAVi inquiry service. The PDA 32 in the UPnP network 22C is registered as “PDA”, and the application level gateway 23C (UPnP, ApGW) is registered as “apgw” in the UpnP inquiry service.
[0080]
First, in order to control the VCR device 31 on the HAVi network 22A from the PDA 32 on the UPnP network 22C, it is necessary to register the VCR device 31 on the HAVi network 22A in the UpnP network 22C. The PDA 32 allows the user to register the VCR device 31 as “http://my.home.net/VCR” in the UPnP application level gateway 23C from a web browser developed on the PDA 32. This uses a “register” command described as http://any.where.net/!register=“http://my.home.net/VCR ”.
[0081]
If UPnP application level gateway 23C receives this registration request, it sends an inquiry to HAVi application level gateway 23A using an HTTP based protocol to request information about VCR device 31. The HAVi application level gateway 23A returns information related to the VCR device 31 indicated by the URL. On the UPnP application level gateway 23C, a pseudo UpnP device of the VCR device 31 is created using information returned from the HAVi application level gateway 23A. The pseudo device has the name "VCR" and is coupled to the UpnP communication part. When the PDA device 32 wants to control the VCR device 31, the PDA device 32 attempts to discover the VCR device 31 via the UPnP service discovery mechanism. The service discovery mechanism returns a query to the pseudo device created on the UPnP application level gateway 23C. The control command is then delivered to the pseudo device through the UPnP protocol. The pseudo device converts the UPnP request into the HTTP protocol, and forwards the request to the HAVi application level gateway 23A according to the host name portion of http://my.home.net/VCR ". The HAVi application level gateway 23A receives the converted HTTP request and finds the actual VCR device 31 by “VCR” specified in the filename of the URL through the HAVi query service. It is converted into a HAVi command and delivered to the target VCR device 31.
[0082]
While currently using the virtual overlay network skeleton, each application-level gateway 23 is used as a Java application running as a stand-alone process, as well as an HTTP-based gateway for home appliances. Provide an interface and a service discovery system for management devices. Each application level gateway 23 has a simple storage database that interprets attributes including its received URL. It can also work with its basic service discovery systems like Jini and UPnP to handle unknown attributes.
[0083]
Next, the extension of the controller that enables sending of additional information such as user preferences, personal authentication, environment information, etc., as well as commands sent to the gateway, will be described. Controllers that can generate HTTP-based control commands themselves are used to send various amounts of information, thereby improving the cooperative relationship between the controller and the gateway. Examples of such information include settings and environment variables customized for the user. The controller here is an extended web browser that can generate commands as proposed above. An extended web browser can send environment variables to the gateway by incorporating it in the HTTP-based commands it sends. HTTP-based commands before environment variables are built in are, for example, “http: //% (HOME) /? OWNER =% (USER) &? Location =% (LOC) &? Function = tv /! Power = on ". This command means that the TV set whose owner is “user” and whose position is “LOC” in “HOME” is to be turned on. Let's assume the environmental information that the controller has about itself. It is assumed that the user has information such as “USER = foo”, “HOME = http: //my.home.net/”, and “LOC = living-room”.
[0084]
The controller uses “% (” as the beginning of the environment variable. The character string enclosed between “% (“ and ”)” is the name of the environment variable. The part of “% ()” Replaced with the value of the corresponding environment variable, in this case the command sent is "http://my.home.net/?=OWNER=foo&location=living-room&function=tv/!power=on".
[0085]
The environmental information held by the controller is updated according to the position of the controller itself, the user currently using the controller, and other environmental parameters. Even if the same button of the same controller is pressed, the transmitted command may be different depending on the state of the button being pressed. Other examples of environmental information that can be used to influence the control of household equipment may be weather information, user emotions, and the like.
[0086]
Most standards are based on object models, but there are many differences between the standards. Jini is a Java-based infrastructure that integrates remote services and devices. The Jini system provides service construction, verification, and communication mechanisms in a distributed system. However, Jini relies heavily on the Java language, and its runtime system requires a large amount of computing resources, which are usually extremely limited for home use. UPnP (Universal Plug and Play) is a configuration that provides a peer-to-peer network connection between a personal computer and a device. UPnP has the ability to dynamically join a device to the network, assign itself an IP address, and respond to its presence and requests. UPnP is based on TCP / IP and web technology, enabling seamless proximity networks in addition to control and data transmission between networked devices in homes and offices. However, UPnP is designed to demonstrate the features and capabilities of each device in an XML file. Profiles based on XML are difficult for home appliances to interpret XML files because they require complex and time-consuming explanations of device capabilities, contrary to Jini's simple service attributes.
[0087]
HAVi (Home Audio Video Interoperability) provides a home network standard for seamless connection of digital audio and video consumer equipment. HAVi also provides a Java API for AV device control that enables control of each device from within the program. HAVi assumes that each device has an IEEE1394 network interface that has sufficient bandwidth and can transmit digital audio and multiple signal streams of video. However, these requirements have hampered the widespread use of HAVi in various types of equipment.
[0088]
Future home appliances are expected to support different standards according to their manufacturer's policy. However, these standards do not support a variety of home networks. The proposed virtual overlay network allows all household devices to be connected and controlled.
[0089]
The Open Services Gateway specification (OSGi) is a Java-based application layer skeleton that provides service providers, device manufacturers, and device manufacturers with neutral application and device layer APIs and functionality. This strategy allows virtually any emerging home network infrastructure, protocols and services to interact seamlessly with back-end services using existing residential telephone lines, cable TV or wire. . This technology needs to be independent of the platform, and as a result, can be used on various computing environments, communication environments, consumer electronics and household products and platforms. The Open Service Gateway specification complements and improves current network standards and enterprise minds because it focuses on providing a gateway interface for the open system layer and service gateway. Some of these include Jini, Bluetooth, CAL, CEBus, HAVi, Home API, HOME-PAN, HomePnP, HomeRF and VESA.
[0090]
The open service gateway specification also maintains consumer investment in future high performance home devices. For example, today, when a consumer switches from a home security provider to another provider, all of the internal network must be replaced. By selecting a device that is compatible with the Open Service Gateway specification, consumers can switch between any of the products of various vendors without having to replace virtually any network infrastructure.
[0091]
The advantage of OSGi is that it provides a framework for building scalable home gateways. This standard is adopted to implement a scalable application level home gateway.
[0092]
The above embodiment has proposed a virtual overlay network that integrates networked home devices. The virtual overlay network determines the message transmission route and converts protocols and messages according to the characteristics of the network and the device. The virtual overlay network is very useful for performing internet-scale ubiquitous computing.
[0093]
The IP layer should also provide the functionality necessary to build a virtual overlay network, and the virtual overlay network is customized for each device that requires complex communication. Most of this functionality should be performed above the IP layer and further customized for each device. Therefore, support for functions at the IP layer should be minimized, and giving some advanced functions to the IP layer in a wide area should be avoided because it is performed at the IP layer. This is because the functionality is too broad and not powerful enough to build real advanced applications.
[0094]
The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the present invention.
[0095]
【The invention's effect】
According to the configuration of the first aspect of the present invention, functions similar to directory services and automatic configuration management necessary for creating a complex home computing environment without modifying a home device having a web server. It becomes possible to have.
[0096]
Moreover, according to the network construction apparatus for device integration, construction of a ubiquitous computing environment based on the HTTP protocol can be achieved.
[Brief description of the drawings]
FIG. 1 is a schematic explanatory diagram showing the overall configuration of a network construction device according to a first embodiment of the present invention.
FIG. 2 is a diagram showing an example of a URL description for identifying and controlling the device.
FIG. 3 is a schematic explanatory diagram showing an example in which the network construction device in FIG. 1 is developed.
FIG. 4 is a schematic explanatory diagram of a network construction device showing a second embodiment of the present invention.
FIG. 5 is a schematic explanatory diagram showing a functional configuration of a gateway connecting the Internet and the home network.
FIG. 6 is a schematic explanatory diagram showing the connection form of the home network.
[Explanation of symbols]
1 Communication means (network network)
2 Equipment
3 HTTP client (terminal)
4 Gateway server
11 PDA equipment (terminal)

Claims (1)

A terminal owned by the user,
Connect the gateway server to the network that connects the device to be controlled with the built-in web server,
This gateway server automatically collects information on currently available devices and presents the contents to the terminal, automatic configuration management means,
When a command for controlling the target device is transmitted from the terminal, device access means for accessing the URL to control the target device by translating the URL included in the command;
Search means for periodically sending an inquiry message using the HTTP protocol to all connectable addresses on the network,
When the device receives the inquiry message from the search means within a given expiration date, the device obtains information including the expiration date of itself and the available command formed in a format based on the URL. Return it to the search means,
The search means registers the information in a database or updates the database and sends the inquiry message to the device within the expiration date specified in the information,
When receiving a discovery request from the terminal, the search means selects a currently available device from the database using a full-text search technology.

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