Method for determining rogue wireless access point (AP)

Abstract

A method for determining a rogue wireless access point (AP), applied to a Fiber-to-the-Room (FTTR) network or a mesh network. The method comprises: a CPE management platform (CMP) determines, on the basis of a serial number (SN) of an AP, whether the AP is registering with the CMP for the first time; if the AP is registering for the first time, the CMP acquires a media access control address (MAC) of a home gateway (HGW) uplinked to the AP and an uplink port of the AP, and stores the MAC and the uplink port in a database; and if the AP is not registering for the first time, the CMP acquires the MAC of the HGW uplinked to the AP and the uplink port of the AP, determines whether the database contains the MAC, and if the database does not contain the MAC, compares the uplink port of the AP not registering for the first time with the uplink port of the AP stored in the database, and determines whether the AP is a rogue AP on the basis of the comparison result.

Description

Method for determining illegal wireless access point AP

[0001] Cross-reference to related disclosures

[0002] The present disclosure is based on Chinese Patent Publication 2024105888450 entitled "Method for determining illegal wireless access point AP" filed on May 13, 2024, and claiming priority to the same, the disclosure of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0003] Embodiments of the present disclosure relate to the field of communication, in particular to a method for determining illegal wireless access point AP. BACKGROUND

[0004] In order to improve the quality of home broadband network and reduce user complaint rate, operators begin to promote Fiber to The Room (FTTR) and multi-wireless router Mesh networking solutions in the market. By deploying FTTR devices or multiple wireless routers supporting Mesh networking in user homes or small businesses, Wi-Fi coverage quality is greatly improved, and user satisfaction is improved.

[0005] Currently, in order to facilitate user use, home FTTR slave devices do not need to be authenticated when accessing the main FTTR device, and wireless routers use standard Ethernet technology and do not require access authentication. Therefore, stolen or stolen FTTR slave devices and wireless routers can also be used normally in other user homes, and cannot be controlled.

[0006] The operator's broadband package includes several FTTR slave devices or wireless routers. However, many users give away or sell the wireless routers in the package, and some wireless routers in public business places (such as coffee shops) are stolen and used.

[0007] According to statistics of a certain operator, about 20% of the FTTR slave devices or wireless routers purchased by the operator are used in other operator networks. Therefore, many operators hope to be able to discover the use of stolen FTTR slave devices or wireless routers in time, that is, to discover illegal FTTR slave devices or wireless routers. SUMMARY

[0008] Embodiments of the present disclosure provide a method for determining illegal wireless access point AP.

[0009] According to one embodiment of the present disclosure, a method for determining an illegal wireless access point (AP) is provided, comprising: a terminal management system (CMP) determining whether the AP is registered to the CMP for the first time according to a registration serial number (SN) of the wireless access point (AP); in the case that the AP is registered for the first time, the CMP obtaining a media access control (MAC) address of a home gateway (HGW) connected to the AP and an uplink port of the AP, and storing the MAC address and the uplink port into a database; in the case that the AP is not registered for the first time, the CMP obtaining the MAC address of the HGW connected to the AP and the uplink port of the AP, and determining whether the MAC address is included in the database, in the case that the MAC address is not included in the database, comparing the uplink port of the AP registered for the first time with the uplink ports of the APs in the database, and determining whether the AP is an illegal AP according to a comparison result.

[0010] According to another embodiment of the present disclosure, a computer program product is also provided, comprising a computer program and instructions, wherein the computer program and instructions are executed by a processor to implement the steps in the above method embodiments.

[0011] According to still another embodiment of the present disclosure, a computer readable storage medium is also provided, wherein the computer readable storage medium stores a computer program, and the computer program is configured to execute the steps in the above method embodiments when running.

[0012] According to yet another embodiment of the present disclosure, an electronic device is also provided, comprising a memory and a processor, wherein the memory stores a computer program, and the processor is configured to run the computer program to execute the steps in the above method embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0013] FIG. 1 is a hardware structure block diagram of a computer terminal for determining an illegal wireless access point (AP) according to an embodiment of the present disclosure;

[0014] FIG. 2 is a flowchart of a method for determining an illegal wireless access point (AP) according to an embodiment of the present disclosure;

[0015] FIG. 3 is a structure block diagram of an apparatus for determining an illegal wireless access point (AP) according to an embodiment of the present disclosure;

[0016] FIG. 4 is a schematic diagram of a connection between a home network and a terminal management system according to an embodiment of the present disclosure;

[0017] FIG. 5 is a flowchart of an initial record process of an AP according to an embodiment of the present disclosure;

[0018] FIG. 6 is a flowchart of a method for determining an illegal wireless access point (AP) according to still another embodiment of the present disclosure. DETAILED DESCRIPTION

[0019] Hereinafter, the embodiments of the present disclosure will be described in detail with reference to the drawings and in conjunction with the embodiments.

[0020] It should be noted that the terms "first", "second" and the like in the description and claims of the present disclosure and the above drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence.

[0021] The method embodiments provided in the embodiments of the present disclosure can be executed in a mobile terminal, a computer terminal or similar computing device. Taking the case of running on a computer terminal, Fig. 1 is a hardware structure block diagram of a computer terminal of a method for determining an illegal wireless access point AP according to an embodiment of the present disclosure. As shown in Fig. 1, the computer terminal can include one or more (only one is shown in Fig. 1) processors 102 (the processor 102 can include but is not limited to a processing device such as a microprocessor MCU or a programmable logic device FPGA) and a memory 104 configured to store data, wherein the computer terminal can further include a transmission device 106 configured to have a communication function and an input and output device 108. Those skilled in the art can understand that the structure shown in Fig. 1 is only schematic, which does not limit the structure of the computer terminal. For example, the computer terminal can further include more or less components than those shown in Fig. 1, or have a different configuration from that shown in Fig. 1.

[0022] The memory 104 can be configured to store computer programs, for example, software programs of application software and modules, such as a computer program corresponding to the method for determining an illegal wireless access point AP in the embodiments of the present disclosure. The processor 102 executes various function applications and data processing by running the computer programs stored in the memory 104, that is, implements the above method. The memory 104 can include a high-speed random access memory, and can further include a non-volatile memory, such as one or more magnetic storage devices, flash memories, or other non-volatile solid-state memories. In some examples, the memory 104 can further include a memory remotely arranged with respect to the processor 102, which can be connected to the computer terminal through a network. Examples of the above network include but are not limited to the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof.

[0023] The transmission device 106 is configured to receive or send data via a network. The specific examples of the above network can include a wireless network provided by a communication provider of the computer terminal. In one example, the transmission device 106 includes a network adapter (Network Interface Controller, NIC), which can be connected to other network devices through a base station so as to communicate with the Internet. In one example, the transmission device 106 can be a radio frequency (Radio Frequency, RF) module, which is configured to communicate with the Internet in a wireless manner.

[0024] In the embodiment, a method for determining an illegal wireless access point AP running on the computer terminal is provided. FIG.2 is a flowchart of determining an illegal wireless access point AP according to the embodiment of the present disclosure. As shown in FIG.2, the flow includes the following steps.

[0025] In step S202, a Customer Premise Equipment (CPE) management platform (CMP), i.e., a terminal management system, determines whether the wireless access point (AP) is registered for the first time to the CMP according to a serial number (SN) of the AP.

[0026] It should be noted that the AP can be an FTTR device, a wireless router or other types of networking devices.

[0027] In step S204, in the case that the AP is registered for the first time, the CMP acquires a media access control address (MAC) of a home gateway (HGW) to which the AP is connected and an uplink port of the AP, and saves the MAC and the uplink port to a database; in the case that the AP is not registered for the first time, the CMP acquires a (Media Access Control Address, MAC) of a HGW to which the AP is connected and an uplink port of the AP, and determines whether the MAC is included in the database. In the case that the MAC is not included in the database, the CMP compares the uplink port of the AP registered for the second time with the uplink ports of the APs in the database, and determines whether the AP is an illegal AP according to a comparison result.

[0028] In one embodiment, the illegal AP is an AP that is illegally stolen.

[0029] In step S204 of the embodiment of the present disclosure, saving the MAC and the uplink port to the database includes: recording the MAC in a MAC list corresponding to the AP, and saving the MAC list, the uplink port of the AP and a time when the AP is registered for the first time to the database.

[0030] In step S204 of the embodiment of the present disclosure, determining whether the AP is an illegal AP according to the comparison result includes: in the case that the comparison result is that the uplink port of the AP registered for the second time is the same as the uplink ports of the APs in the database, determining that the AP is an illegal AP; and in the case that the comparison result is that the uplink port of the AP registered for the second time is different from the uplink ports of the APs in the database, determining that the AP is not an illegal AP.

[0031] In step S204 of the embodiment of the present disclosure, the CMP acquires the media access control address (MAC) of the home gateway (HGW) connected to the AP and the uplink port of the AP, including: the CMP acquires the working mode of the AP; in the case that the working mode of the AP is the controller mode, the CMP acquires the MAC of the connected device of the AP and the uplink port of the AP, wherein the connected device is the home gateway; in the case that the working mode of the AP is the proxy mode, the CMP acquires the information of the connected device of the AP, and finds the connected device according to the information, and acquires the MAC of the HGW connected to the connected device, wherein the information of the connected device includes the MAC or the serial number (SN).

[0032] It should be noted that the AP in the controller mode is responsible for the management and control of the entire network, and the AP in the proxy mode is mainly responsible for providing basic network connection functions.

[0033] In the exemplary embodiment of the present disclosure, after determining that the AP is an illegal AP, the method further includes: saving the identifier of the AP into an illegal AP list, and issuing a prohibition instruction to the AP.

[0034] In one embodiment, after discovering the illegal AP, the function of the illegal AP is limited, thereby reducing the probability of the AP device being misused and becoming an illegal AP.

[0035] In the exemplary embodiment of the present disclosure, after determining that the AP is not an illegal AP, the method further includes: saving the MAC of the HGW connected to the AP which is not registered for the first time into a database.

[0036] In the exemplary embodiment of the present disclosure, the CMP acquires the MAC of the wide area network (WAN), the local area network (LAN) and the wireless fidelity (Wi-Fi) interface of the AP.

[0037] According to the embodiments of the present disclosure, the MAC of the HGW connected to the AP for the first time and the uplink port of the AP are acquired and stored, which is equivalent to recording the HGW initially associated with the AP. In the case that the AP is not registered for the first time, the MAC of the HGW connected to the AP is also acquired. If the AP does not change the uplink gateway device during the period from the first registration to the current registration, the acquired HGW MAC should be the same as that acquired in the first registration, that is, the acquired HGW MAC can be found in the database. If the acquired HGW MAC is not found in the database, it is indicated that the AP can be an illegal AP and needs to be further checked and determined. Therefore, the problem that an AP cannot be determined to be illegal in time due to the lack of attention to the uplink gateway and the uplink port of the AP in the related art can be solved. The change of the uplink gateway and the uplink port of the AP registered for the first time can be found in time, and the AP with the change can be checked to determine whether the AP is illegal, thereby achieving the effect of accurately determining the legality of the AP.

[0038] Those skilled in the art can clearly understand the method according to the above embodiments can be realized by means of software and the necessary general hardware platform, of course, it can also be realized by hardware, but in many cases, the former is a better implementation. Based on such understanding, the technical solutions of the present disclosure can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes a plurality of instructions for causing a terminal device (which can be a mobile phone, computer, server, or network device) to execute the method described in the embodiments of the present disclosure.

[0039] In the embodiments, a device for determining an illegal wireless access point AP is also provided, which is configured to implement the above embodiments and preferred embodiments, and will not be described herein. As used below, the term "module" can be a combination of software and / or hardware that implements a predetermined function. Although the device described in the following embodiments is preferably implemented in software, hardware or a combination of software and hardware is also possible and is contemplated.

[0040] FIG. 3 is a structural block diagram of a device for determining an illegal wireless access point AP according to an embodiment of the present disclosure. As shown in FIG. 3, the device includes a judging module 10 and a determining module 20.

[0041] The judging module 10 is configured to determine whether the AP is registered for the first time according to the registration serial number SN of the wireless access point AP.

[0042] The determining module 20: in the case of first registration of the AP, the MAC of the home gateway HGW connected to the AP and the uplink port of the AP are obtained and saved in the database; in the case of non-first registration of the AP, the MAC of the HGW connected to the AP and the uplink port of the AP are obtained, and it is determined whether the MAC is included in the database; in the case that the MAC is not included in the database, the uplink port of the AP of non-first registration is compared with the uplink port of the AP in the database, and it is determined whether the AP is an illegal AP according to the comparison result.

[0043] It should be noted that the above modules can be implemented by software or hardware, and for the latter, the following implementation manners can be used, but are not limited thereto: the above modules are located in the same processor; or the above modules are located in different processors in any combination.

[0044] The embodiment of the present disclosure further provides a computer readable storage medium, which stores a computer program, and the computer program is configured to execute the steps in any one of the method embodiments when running.

[0045] In an example embodiment, the computer readable storage medium can include, but is not limited to, a U disk, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk or an optical disk, and various media that can store computer programs.

[0046] The embodiment of the present disclosure further provides an electronic device, which comprises a memory storing a computer program and a processor configured to execute the computer program to perform the steps in any one of the method embodiments.

[0047] In an example embodiment, the electronic device can further comprise a transmission device connected to the processor and an input / output device connected to the processor.

[0048] The specific examples in the embodiment can refer to the examples described in the above embodiments and example embodiments, and the embodiment will not be described here again.

[0049] To facilitate the understanding of the technical solutions provided by the present disclosure, the following will be described in detail in conjunction with the embodiments of specific scenarios.

[0050] Traditional solutions to determine whether an AP is illegal include the following two solutions, solution 1: setting a device MAC list and IP address range, which is based on the relationship between the device and the region, checks whether the IP belongs to a certain operator and the region to determine whether the device is used by other operators or used in different regions of the same operator, and cannot find the theft between different families in the same region of the same operator.

[0051] Solution 2: Find AP theft by checking the change of Point-to-Point Protocol Over Ethernet (PPPoE) account on Ethernet, and the management platform queries whether the corresponding PPPoE account of the device has changed according to the Internet Protocol (IP) and port number of the device connected to the management platform, and queries the device Authentication, Authorization, and Accounting (AAA) server to determine whether the device has been stolen. The disadvantage of this solution is that it needs to query the massive logs of the AAA server, and the query efficiency is low in the face of a large number of user devices.

[0052] FIG. 4 is a schematic diagram of a home network and terminal management system connection according to an embodiment of the present disclosure, as shown in FIG. 4, the home network includes an HGW and an AP, wherein the AP can be an FTTR device, a wireless router or other types of networking devices, and the HGW is usually an ONU. The AP includes an AP (Controller), which is an AP working in controller mode, and an AP (Agent), which is an AP working in agent mode, and the AP (Controller) is the uplink device of the AP (Agent). It should be noted that in the FTTR network, the AP (Controller) has a stronger association with the HGW, and the possibility of the AP (Controller) being an illegal AP is smaller; in the Mesh networking, the AP (Controller) and the AP (Agent) have no big difference in the possibility of being illegal APs. The AP is preconfigured with information of the CMP, and the CMP and the AP have a management protocol, which includes Message Queuing Telemetry Transport (MQTT), Technical Report-069 (TR-069), which is a communication agreement for remote control of user terminal devices developed on CPE WAN Management Protocol (CWMP), or User Services Platform (TR-369) developed by BBF.

[0053] Figure 5 is a flow chart of an AP initial record procedure according to an embodiment of the present disclosure, and the specific procedure is shown as follows.

[0054] Step S501, AP1 acquires an address from HGW.

[0055] Specifically, AP1 acquires an IP address from HGW.

[0056] Step S502, AP1 registers with CMP, and CMP discovers that AP1 is a first registration according to the registered SN number.

[0057] Step S503, CMP acquires the uplink port of AP1 and records it.

[0058] Step S504, CMP acquires the working mode of AP1.

[0059] Specifically, CMP acquires the working mode of AP1 as Controller and records it.

[0060] Step S505, CMP acquires the MAC of the LAN port, Wi-Fi, and WAN port of AP1 and saves it to the database.

[0061] Step S506, CMP acquires the MAC of the uplink device of AP1 and records it.

[0062] Specifically, the uplink device of AP1 is HGW, and the MAC of HGW of AP1 is recorded in the MAC list, and the uplink port and registration time of AP1 are also recorded.

[0063] It should be noted that the uplink port here is equivalent to the uplink port.

[0064] Step S507, AP2 registers with CMP, and CMP discovers that AP2 is a first registration according to the registered SN number.

[0065] Step S508, CMP acquires the uplink port of AP2 and records it.

[0066] Step S509, CMP acquires the working mode of AP2.

[0067] Specifically, CMP acquires the working mode of AP2 as Agent and records it.

[0068] Step S510, CMP acquires the MAC or SN of the uplink device of AP2.

[0069] Specifically, the CMP acquires the MAC or SN of the uplink device controller of the AP2, and finds the AP1 according to the MAC or SN of the controller, adds the HGW MAC of the AP1 to the MAC list of the AP2, and records the SN or MAC of the AP1.

[0070] After the AP completes the initial recording, each time the AP is powered on and registered on the CMP, the CMP acquires the MAC address mac2 of the HGW of the AP according to the process in the initial recording, and if the mac2 is not in the uplink MAC list, the following checks are performed: the scenarios include at least the following three.

[0071] Scenario 1: The AP works in a non-Mesh mode or a controller mode of the Mesh, the CMP finds that the uplink port of the AP does not change, and the MAC of the HGW of the uplink changes, indicating that the AP is an abnormal uplink device. The AP is put into the "illegal AP" list.

[0072] Scenario 2: The AP works in a proxy mode of the Mesh, the CMP finds that the uplink port of the AP or the uplink port of the controller of the uplink of the AP does not change, and the MAC of the HGW of the AP changes, indicating that the AP is an abnormal uplink device. The AP is put into the "illegal AP" list.

[0073] Scenario 3: The CMP finds that the uplink port of the AP changes, for example, the initial Ethernet port is now Wi-Fi, and the uplink MAC changes. Generally, the change of the MAC is small, indicating that the change of the MAC address of the HGW is caused by the replacement of the interface. At this time, the new MAC address of the HGW of the AP is recorded in the MAC list of the AP.

[0074] It should be noted that the uplink port in the above scenarios is equivalent to the uplink port.

[0075] FIG. 6 is a flowchart of a method for determining an illegal wireless access point AP according to another embodiment of the present disclosure, and the specific process is as follows.

[0076] Step S601: Acquire the MAC address mac0 of the HGW of the AP.

[0077] Specifically, each time the AP is powered on, the CMP registers, and the CMP finds that it is not the first registration. The CMP acquires the MAC address mac0 of the HGW of the AP (the process is similar to the "AP initial recording process", but this time the MAC list is not updated).

[0078] Step S602: The CMP checks whether the mac0 is in the MAC list of the AP.

[0079] Specifically, if yes, the process ends, and if no, step S603 is entered.

[0080] Step S603, check whether the uplink port of the AP changes.

[0081] Specifically, if the uplink port of the AP changes, go to step S606, if the uplink port of the AP does not change, go to step S604.

[0082] Step S604, check whether the AP works in the proxy mode.

[0083] Specifically, if not, it means that the AP is an illegal AP, go to step S607, if yes, go to step S605.

[0084] Step S605, check whether the uplink port of the controller of the AP changes.

[0085] Specifically, if there is no change, it means that the AP is an illegal AP, go to step S607, if there is a change, go to step S606.

[0086] Step S606, add mac0 to the MAC list of the AP.

[0087] Step S607, the AP is an illegal AP, add it to the illegal AP list.

[0088] It should be noted that the uplink port in the embodiment corresponds to the uplink port.

[0089] For the device determined to be an illegal AP, the CMP issues a disable instruction to the device, limiting its normal use. For example, the forwarding function can be turned off, so that the device cannot be used. The Wi-Fi function can also be turned off, so that the Wi-Fi access cannot be used. The disabled AP device can push a Hyper Text Transfer Protocol (HTTP) redirection page to the downlink user terminal (such as a mobile phone), prompting: the device has been disabled, please contact customer service.

[0090] In an embodiment of the present disclosure, if the AP cannot communicate with the CMP for a long time, the AP can enter a self-locking state to prevent the AP from being stolen by shielding the management platform.

[0091] In an embodiment of the present disclosure, when the user's HGW has a problem and is replaced, the correspondence between the AP and the gateway MAC can be updated according to the MAC addresses of the HGW before and after replacement, to avoid false judgment.

[0092] It is apparent that those skilled in the art should understand that the modules or steps of the present disclosure described above can be realized by general computing devices, which can be centralized on a single computing device or distributed on a network composed of multiple computing devices, and can be realized by program codes executable by the computing devices, so that they can be stored in storage devices and executed by the computing devices, and in some cases, the steps shown or described can be executed in different orders, or they can be respectively manufactured into individual integrated circuit modules, or multiple modules or steps thereof can be manufactured into a single integrated circuit module. Thus, the present disclosure is not limited to any particular combination of hardware and software.

[0093] The preferred embodiments of the present disclosure are described above, but the present disclosure is not limited to the above. Those skilled in the art can make various modifications and changes to the present disclosure. Any modification, equivalent replacement, improvement, etc. made within the principles of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A method for determining an illegal wireless access point (AP), applied to a fiber to the room (FTTR) network or a mesh network, comprising: determining, by a central management platform (CMP), whether a wireless access point (AP) is registered to the CMP for the first time according to a registration serial number (SN) of the AP; in a case where the AP is registered for the first time, obtaining, by the CMP, a media access control (MAC) address of a home gateway (HGW) to which the AP is connected and an uplink port of the AP, and saving the MAC address and the uplink port to a database; in a case where the AP is not registered for the first time, obtaining, by the CMP, the MAC address of the HGW to which the AP is connected and the uplink port of the AP, determining whether the MAC address is included in the database, in a case where the MAC address is not included in the database, comparing the uplink port of the AP that is not registered for the first time with the uplink port of the AP in the database, and determining whether the AP is an illegal AP according to a comparison result.

2. The method of claim 1, wherein, obtaining, by the CMP, the MAC address of the HGW to which the AP is connected and the uplink port of the AP, comprises: obtaining, by the CMP, a working mode of the AP; in a case where the working mode of the AP is a controller mode, obtaining, by the CMP, the MAC address of a connected device of the AP and the uplink port of the AP, wherein the connected device is the HGW; in a case where the working mode of the AP is a proxy mode, obtaining, by the CMP, information of a connected device of the AP, finding, by the CMP, the connected device according to the information, and obtaining, by the CMP, the MAC address of the HGW to which the connected device is connected, wherein the information of the connected device comprises the MAC address or the SN.

3. The method of claim 1, wherein, saving, by the CMP, the MAC address and the uplink port to the database, comprises: recording, by the CMP, the MAC address in a MAC address list corresponding to the AP, and saving, by the CMP, the MAC address list, the uplink port of the AP and a time when the AP is registered for the first time to the database.

4. The method of claim 1, wherein, determining, by the CMP, whether the AP is an illegal AP according to the comparison result, comprises: in a case where the comparison result is that the uplink port of the AP that is not registered for the first time is the same as the uplink port of the AP in the database, determining that the AP is an illegal AP; in a case where the comparison result is that the uplink port of the AP that is not registered for the first time is different from the uplink port of the AP in the database, determining that the AP is not an illegal AP.

5. The method of claim 4, wherein, after determining that the AP is an illegal AP, further comprising: saving, by the CMP, an identifier of the AP to an illegal AP list, and issuing, by the CMP, a use prohibition instruction to the AP.

6. The method of claim 4, wherein, after determining that the AP is not an illegal AP, further comprising: saving, by the CMP, the MAC address of the HGW to which the AP that is not registered for the first time is connected to the database.

7. The method of claim 1, wherein, the method further comprises: obtaining, by the CMP, the MAC address of a wide area network (WAN) interface, a local area network (LAN) interface and a wireless fidelity (Wi-Fi) interface of the AP.

8. A computer program product comprising computer programs, instructions, which when executed by a processor implement the steps of the method according to any one of claims 1 to 7.

9. A computer-readable storage medium having stored therein a computer program, wherein, The computer program, when executed by a processor, implements the steps of the method according to any one of claims 1 to 7.

10. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, the processor when executing the computer program implements the steps of the method according to any one of claims 1 to 7.

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