JP2007087174A - Network correspondense information processor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To equip a service providing device with counter information accumulated in compliance with change of profile information for ignoring a profile information request incapable of accurately notifying the counter information and to prevent unnecessary traffic by a simple procedure in a plug-and-play protocol having difficulties in management of credential information for protecting a function of the service providing device against a request from a malicious client device such as a replay attack. <P>SOLUTION: A network service system is constructed of a plurality of client devices connected to a network and a plurality of service providing devices. The service providing device keeps the profile information describing details of a service to be offered and has a function for transmitting the profile information in response to a request from the client device. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a peripheral device corresponding to a network, an information processing device that controls the peripheral device, and a network system including these devices.

  Conventionally, a service providing apparatus and a service providing system that provide a service in response to a service request from a client apparatus on a network are known.

  For example, with the rapid spread of communication over the Internet, network-compatible devices are changing from conventional personal computers to PDA (Personal Digital Assistance), user interactive devices such as mobile phones, scanners, printers, copiers, digital Network support is rapidly progressing to home appliances such as image processing devices such as cameras, televisions, air conditioners, and refrigerators.

  Accordingly, in order to improve convenience and simplicity in using these network-compatible devices, network address automatic setting means, search for network devices that provide services, search means, and network-compatible devices are controlled. Various protocols have been proposed that provide automatic setup means such as application software, utility software, and operating systems.

  Focusing on network device search and search means For example, in the case of UPnP (registered trademark), means for specifying a simple service name such as print or scan as a search condition in the search condition UPnP (registered trademark) SSDP (Simple Service Discovery Protocol) For the network service providing device that responds, obtain profile information describing the details of the service, and determine whether the service is desired based on the information described in the profile information is doing.

  In any case, in order for the client device to search for an available device existing on the network, a data packet describing the search condition is transmitted to the network, and the device that has received the data packet satisfies the search condition. The device sends response data in response to the search packet to the client that issued the search packet, and the client device uses the response data to provide a service that the device can provide to the device that sent the response data. It has a procedure for acquiring profile information describing detailed information and analyzing the contents described in the information to determine whether or not to use a service provided by the device.

For example, Patent Document 1 and Patent Document 2 can be cited as conventional examples.
JP 2004-343522 A Special table 2003-513514 gazette

  However, the above-described prior art has the following problems.

  These profile information acquisition methods are not problematic for use in home LANs and small office LANs, where there is no possibility of malicious third-party intervention, but an unspecified number of users can access the network via the intranet or the Internet. When these profile information means are used above, there is a possibility that they may be illegally used by a malicious third party, which may cause great damage to the network system that provides the service.

  For example, if a malicious client frequently issues profile information acquisition request packets, the service providing device that has received the request packet will continue to transmit profile information. If the amount of profile information data is large, communication traffic As a result, the risk of not functioning as a service providing device is increased.

  The present invention has been made to solve the above problems, and has the following configuration.

That is,
A network service system comprising a plurality of client devices connected to a network and a plurality of service providing devices,
The service providing device holds profile information describing the details of the service to be provided,
It has a function of transmitting the profile information in response to a request from a client device,
The service providing device has means for notifying that the description content of the profile information is updated to a client device connected to the network when the description content of the profile information is updated,
The service providing device has a function of holding counter information accumulated in synchronization with the number of times profile information is updated when the description content of profile information is updated, and notifies that the description content of profile information has been updated. And having means for notifying the client device connected to the network of the counter information,
The service providing device has means for transmitting profile information in response to a profile acquisition request issued from a client device when the request is suitable for conditions specified by the service providing device,
The condition specified by the service providing device is characterized in that the client device that issued the profile information acquisition request is not provided with the latest profile information,
The condition specified by the service providing device is that the client device that issued the profile information acquisition request does not have the latest profile information, and the profile information notified to the client device by the service providing device A network service system comprising means for transmitting profile information only when a counter value smaller than a counter value accumulated in synchronization with the number of updates is given to a profile information request.

  As described above, according to the present invention, a service providing device has a BootID that is counter information that accumulates according to changes in profile information, so that it is possible to ignore a profile information request that cannot correctly notify the BootID information. In a plug-and-play protocol where password authentication and credential information are difficult to manage, it is possible to prevent unnecessary traffic with a simple procedure, and to provide the function of a service providing device for requests from malicious client devices such as replay attacks. It became possible to defend.

  Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the protocol, version, address, other numerical values and the like described in this embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified.

  A protocol conversion system as an embodiment of a service providing system according to the present invention will be described.

  FIG. 1 is a block diagram showing the configuration of a printing system as an embodiment of the present invention.

  The client 100 is installed with a general-purpose operating system and a general-purpose application executable on the general-purpose operating system. In the case of the operating system OS 1 shown in the present embodiment, the eXtensible Markup Language ( XML) / Simple Object Access Protocol (SOAP) plug-and-play protocol is used to realize discovery, control, status acquisition, etc. of devices on the network, for example, created by a word processor that is application software 4 The converted document is converted into data that can be printed by the print driver 3 for a UPnP (registered trademark) plug-and-play protocol compatible printer searched and discovered by the plug-and-play protocol processing unit 2. Executing the issuance of a print job via the protocol processing unit 2.

  On the other hand, the network compatible device, in the present embodiment, the network compatible printer 200 includes a TCP / UDP / IP protocol stack 5 as a communication function, and includes an HTTP processing unit 6 on the protocol stack, Perform response processing.

  The upper layer of the HTTP processing unit includes a Simple Object Access Protocol (SOAP) processing unit 7 that performs analysis and response processing of a request used in the UPnP (registered trademark) Plug and Play protocol described in XML-SOAP.

  The plug and play protocol processing unit 8 executes search processing, description processing, control processing, and event processing defined by the UPnP (registered trademark) plug and play protocol in an upper layer of the SOAP processing unit 7. The plug-and-play protocol processing unit 8 has a communication function with the printer controller 9, converts each process specified by the UPnP (registered trademark) plug-and-play protocol into a communication procedure unique to the printer controller, executes a print job, Processing such as obtaining the printer status is executed.

  On a network operated in a large-scale office, a plurality of printers having the same configuration as this network-compatible printer but having different supported functions and processing capabilities are connected.

  Similarly, there may be a situation where a plurality of clients are connected.

  Next, a control flow flowchart according to the present invention will be described with reference to FIG.

  The network compatible printer 200 has BootID that is counter information that is accumulated in accordance with changes in profile information. This counter holds an integer value that is incremented by 1 each time profile information changes. The network compatible printer 200 initializes the counter BootID at startup, and sets 0 in this embodiment (step 1). .

  After the activation, the network compatible printer 200 issues a Notification packet in accordance with the UPnP (registered trademark) Plug and Play protocol convention, and notifies the client device existing on the network that it has joined the network (step 2).

  FIG. 3 shows the format of the Notification packet defined by the UPnP (registered trademark) Plug and Play protocol. In this embodiment, a BootID header is added to notify the value of BootID.

  The client device 100 existing on the network that has received the Notification packet must record and hold the value of BootID described in the packet.

  Next, the network compatible printer 200 monitors whether there is a status change related to the profile information (step 3). When a change in status is detected, the BootID value is incremented by 1 (step 4), and the latest value is set in the BootID header to notify the client device existing on the network that the profile information has been updated. The aforementioned Notification packet shown in FIG. 3 is issued (step 5).

  The client device 100 existing on the network that has received the Notification packet must record and hold the value of BootID described in the packet.

  Next, when the network compatible printer 200 receives the Profile information acquisition request packet issued from the client device 100 (step 6), the network compatible printer 200 analyzes the request packet and determines whether or not profile information can be returned. FIG. 4 shows the format of the Profile information request packet issued from the client. SOAP (Simple Object Access Protocol) is used as the entity body of the HTTP POST request, and the following SOAP function is defined in the present invention. The

GetProfileRequest (BootID, MyURL)
The SOAP function realizes a function of requesting transmission of profile information to the network service providing device, in this embodiment, the network compatible printer 200. The BootID is a client device that issues the request and the network compatible printer. The latest value of BootID recorded and held when the Notification packet issued from 200 is received is set.

  MyURL describes the destination of profile information in the URL format.

  The network compatible printer 200 that has received the packet confirms the presence or absence of an entity body, and if the packet does not have an entity body, ignores the profile transmission request as an illegal request (step 7).

  It is invalid if the entity body exists and the value of BootID that is an argument of the GetProfileRequest function is larger than the latest BootID value held by the network compatible printer 200 or if the value is not described. The profile transmission request is ignored as a request (step 8).

  If the BootID value is smaller than the latest BootID value held by the network compatible printer 200, it means that the client device 100 does not hold the latest profile information. In this case, it is determined whether profile information corresponding to the specified BootID has been transmitted to the URL described in MyURL, which is an argument of the GetProfileRequest function, and the MAC address of the client device 100 that issued the request. If it has already been transmitted, the profile transmission request is ignored as an unauthorized request (step 9).

  If it is determined that it has not been transmitted, the network compatible printer 200 transmits profile information to the URL described in MyURL that is an argument of the GetProfileRequest function (step 10), and the client device that issued the URL information and the request 100 MAC addresses are recorded (step 11).

  Thereafter, the processing from step 3 is repeatedly executed until the power of the network compatible printer 200 is turned off.

  In the first embodiment, an embodiment in which a printer is a network device is shown. However, as a network compatible device, a storage device such as a hard disk, a scanner, a copying machine, and a device having these combined functions, and having a communication function. Any device having a communication function capable of providing a service to a client device can be realized in any case.

  In the first embodiment, the BootID is assigned by using Notification specified in UPnP (registered trademark) v1 as a service search protocol. However, the update of profile information can be notified in the event format. If so, it can be implemented in other protocols.

  Further, although XML-SOAP is used to acquire profile information in the first embodiment, BootID and profile information transmission destination description means include other description means such as CSV (Comma Separated Value), simple text, or Even a binary description can be realized.

  Further, although HTTP is used in the first embodiment as a protocol for notifying these pieces of information, it can be realized even when another protocol such as FTP is used.

1 is a diagram illustrating functional configurations of a client and a network-compatible printer that configure a network system as an embodiment of the present invention. The flowchart which shows the control procedure in this invention The figure which shows the format of the Notification packet in this invention The figure which shows the format of the Profile information request packet in this invention

Claims (6)

A network service system comprising a plurality of client devices connected to a network and a plurality of service providing devices,
The service providing device holds profile information describing the details of the service to be provided,
A network service system having a function of transmitting the profile information in response to a request from a client device.   2. The service providing device according to claim 1, further comprising means for notifying the client device connected to the network that the description content of the profile information is updated when the description content of the profile information is updated. Network service system described in 1.   The service providing device has a function of holding counter information accumulated in synchronization with the number of times profile information is updated when the description content of profile information is updated, and notifies that the description content of profile information has been updated. 3. The network service system according to claim 1, further comprising means for notifying the counter information to a client device connected to the network.   The service providing device has means for transmitting profile information in response to a profile acquisition request issued from a client device when the request is suitable for conditions specified by the service providing device. Item 4. The network service system according to Item 1.   5. The network service system according to claim 4, wherein the condition specified by the service providing device is that a client device that has issued a profile information acquisition request does not have the latest profile information. .   The condition specified by the service providing device is that the client device that issued the profile information acquisition request does not have the latest profile information, and the profile information notified to the client device by the service providing device 6. The network service system according to claim 5, further comprising means for transmitting profile information only when a counter value smaller than a counter value accumulated in synchronization with the number of updates is added to the profile information request.

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