JP5368177B2 - Remote security system by mobile phone - Google Patents

Description

  The present invention relates to a remote security system using a mobile phone, and more particularly to a remote security system using a mobile phone that unlocks an entrance door in a building by remote control.

  For example, in buildings and facilities such as office buildings, factories, laboratories, hospitals, etc., security systems have been adopted in which employees are given personal authentication cards to perform personal authentication when entering and exiting rooms.

  However, in this security system using a personal authentication card, for example, if an employee notices that the personal authentication card has been left at home at the entrance of the room, or if the employee has lost the personal authentication card on the way to work, or There is a possibility that an emergency may occur and the room entrance / exit must be unlocked without a personal authentication card. In these cases, it is common to issue a temporary personal authentication card or reissue a complicated and time-consuming personal authentication card. Further, when an emergency occurs, the security system itself using a personal authentication card may be counterproductive.

  On the other hand, Patent Document 1 discloses a personal authentication method and system using a mobile phone. Here, it is described that the user's member ID and password are individually managed secretly by the authentication support system and the entrance management server, respectively, and the entrance door is unlocked when each authentication is successful.

JP 2005-128847 A

  In the conventional security system, for example, when an employee or the like notices that he / she has left his / her personal authentication card at the entrance / exit of the room, the employee loses his / her personal authentication card on the way to work, or an emergency occurs. Issue a temporary personal authentication card or reissue a complicated and time-consuming personal authentication card when it is necessary to unlock the entrance / exit of the room without a personal authentication card. Such complicated procedures were necessary.

  In addition, in a building or facility having a plurality of rooms, when the above situation occurs, it is necessary to specify which door of the door to be unlocked. However, the conventional security system does not take measures against this point. For this reason, employees who have forgotten their personal authentication card, employees who have lost their personal authentication card, etc. have had to take time to explain to the security center by telephone or to prepare documents.

  In addition, in the conventional security system, it is impossible to determine whether an employee who has lost the personal authentication card is in front of the door of the door to be unlocked. was there.

  The object of the present application is to solve such problems and provide a remote security system using a mobile phone that can unlock the door of an entrance / exit by a simple operation and has high security.

  In order to achieve the above object, a remote security system using a mobile phone according to the present invention is a remote security system that unlocks an entrance door in a building by remote control, and is a mobile phone mail possessed by a registered user. A personal information storage unit for storing an address and an answer phrase registered by the user for the set question phrase, a blank mail receiving unit for receiving blank mail transmitted from the user's mobile phone, and an individual Includes a mobile phone confirmation unit that confirms the user's own mobile phone by the registered email address of the user stored in the information storage unit, a one-time ID, a question phrase, and a telephone number of the automatic telephone response means A reply mail sending unit that sends the reply mail to the user, and a reply mail that is sent back from the user's mobile phone and includes a one-time ID and a reply phrase Email automatic answering means comprising a reply mail receiving part, a user authentication part that authenticates the user by comparing the returned answer phrase and the registered answer phrase, and an automatic telephone answering means by the user using a mobile phone Automatic telephone response means that asks for the one-time ID and the unique door code displayed on the doorway to be unlocked and authenticates the user and confirms the position from the answer And a remote security management server that unlocks the entrance / exit door corresponding to the door code when both the user authentication unit of the automatic mail response unit and the automatic telephone response unit authenticate themselves, To do.

  With the above configuration, in the remote security system using a mobile phone, the user authentication unit of the automatic mail response means authenticates the person with the one-time ID and the response phrase included in the response mail sent from the user's mobile phone, The automatic telephone answering means authenticates the person based on the one-time ID and the unique door code displayed on the doorway to be unlocked. In this way, by using the mail function and the telephone function of the mobile phone, the personal authentication can be performed simply by operating only the mobile phone. Further, when the remote security management server authenticates that the user authentication unit of the automatic mail response means and the automatic telephone response means are authentic, the remote control management server causes the security control device to unlock the doorway corresponding to the door code. As described above, this system can allow the user to unlock the entrance door by a simple means by using both the automatic mail answering means and the automatic telephone answering means. Furthermore, this system assigns unique ID codes to a plurality of entrance doors and displays them on the entrance doors, thereby confirming that the user is in front of the entrance doors and having higher security. .

  In the remote security system using a mobile phone, the personal information storage unit stores the mobile phone number of the user of the system in association with the mail address, and the automatic telephone response means stores the registered mobile phone stored in the personal information storage unit. It is preferable to confirm the identity of the mobile phone by comparing the phone number with the called mobile phone number. Thereby, the automatic telephone response means can confirm whether or not the mobile phone is automatically registered from the mobile phone number registered by the user.

  In the remote security system using a mobile phone, the personal information storage unit stores a plurality of sets of different question phrases and answer phrases, and the user authentication unit randomly selects a question phrase from the plurality of question phrases. It is preferable to make the reply mail transmission unit reply. Thereby, security can be secured even when an answer phrase for a specific question phrase leaks to another person or when an answer phrase for a specific question phrase is easy to guess.

  In addition, the remote security management system using a mobile phone causes the remote security management server to select two or more question phrases from a plurality of question phrases according to the level of security input, and reply to the reply mail transmission unit. It is preferable to make it. Thereby, even when security needs to be improved due to security requirements, it can be easily handled.

  Further, in the remote security system using a mobile phone, the remote security management server may delete the registered answer phrase for the selected question phrase with respect to the personal information storage unit, and allow the user to register a new answer phrase. preferable. Thereby, the degree of security of an answer phrase can be raised.

  To achieve the above object, a remote security method using a mobile phone according to the present invention is a remote security method for unlocking an entrance door in a building by remote control, and is a mobile phone mail possessed by a registered user. Storing an address and an answer phrase registered by the user for the set question phrase, receiving an empty mail transmitted from the user's mobile phone, and storing the stored user A step of confirming the user's own mobile phone by the e-mail address, a step of sending a reply e-mail including the one-time ID, the question phrase, and the telephone number of the automatic telephone answering system to the user; Receive a reply e-mail containing a one-time ID and answer phrase, and a reply answer phrase registered. A step of authenticating the person from the comparison with the answer phrase, and a unique door displayed on the doorway that is unlocked with the one-time ID when the user calls the telephone number of the automatic telephone answering system with a mobile phone Asking the code, replying to the user's identity verification and location confirmation, and verifying both by email and telephone identity verification, the door corresponding to the door code is opened. And unlocking.

  With the above configuration, in the remote security method using a mobile phone, the user authentication unit of the automatic mail response means authenticates the person with the one-time ID and the response phrase included in the response mail sent from the user's mobile phone, The automatic telephone answering means authenticates the person based on the one-time ID and the unique door code displayed on the doorway to be unlocked. In this way, by using the mail function and the telephone function of the mobile phone, the personal authentication can be performed simply by operating only the mobile phone. Further, when the remote security management server authenticates that the user authentication unit of the automatic mail response means and the automatic telephone response means are authentic, the remote control management server causes the security control device to unlock the doorway corresponding to the door code. As described above, this system can allow the user to unlock the entrance door by a simple means by using both the automatic mail answering means and the automatic telephone answering means. Furthermore, this system assigns unique ID codes to a plurality of entrance doors and displays them on the entrance doors, thereby confirming that the user is in front of the entrance doors and having higher security. .

  In addition, the remote security method using a mobile phone stores the mobile phone number of the user in association with the e-mail address, and when the user calls the telephone number of the automatic telephone answering system by the mobile phone, the stored registration is stored. It is preferable to confirm the identity of the mobile phone by comparing the mobile phone number with the called mobile phone number. Thereby, the automatic telephone response means can confirm whether or not the mobile phone is automatically registered from the mobile phone number registered by the user.

  In the remote security method using a mobile phone, it is preferable to store a plurality of sets of different question phrases and corresponding answer phrases, and to randomly select a question phrase from the plurality of question phrases. Thereby, security can be secured even when an answer phrase for a specific question phrase leaks to another person or when an answer phrase for a specific question phrase is easy to guess.

  In the remote security method using a mobile phone, it is preferable to select two or more question phrases from a plurality of question phrases according to the input security level. Thereby, even when security needs to be improved due to security requirements, it can be easily handled.

  Furthermore, it is preferable that the remote security method using a mobile phone deletes the answer phrase registered for the selected question phrase and causes the user to register a new answer phrase. Thereby, the degree of security of an answer phrase can be raised.

  As described above, according to the remote security system using a mobile phone according to the present invention, it is possible to provide a remote security system using a mobile phone that can unlock the entrance door with a simple operation and has high security.

It is the block diagram and explanatory drawing which show schematic structure of one Embodiment of the remote security system by the mobile telephone which concerns on this invention. It is the block diagram and explanatory drawing which show a response with a user's mobile telephone and a mail automatic response means. It is the block diagram and explanatory drawing which show the response with a user's mobile telephone and an automatic telephone response means. It is explanatory drawing which shows one Example of the registration question phrase memorize | stored in the personal information storage part, and the registration reply phrase with respect to it. It is a schematic structure of one Embodiment of the remote security method by the mobile telephone which concerns on this invention, and is a flowchart which shows a response with a user's mobile telephone and a mail automatic response means. It is a schematic structure of one Embodiment of the remote security method by the mobile telephone which concerns on this invention, and is a flowchart which shows the response of a user's mobile telephone and an automatic telephone response means. It is a schematic structure of one Embodiment of the remote security method by the mobile telephone which concerns on this invention, and is a flowchart which shows operation | movement of a remote management server.

  Hereinafter, embodiments of a remote security system using a mobile phone according to the present invention will be described in detail with reference to the drawings.

(Remote security system using mobile phone)
FIG. 1 shows a schematic configuration of one embodiment of a remote security system using a mobile phone according to the present invention. The mobile phone remote security system 1 includes an automatic mail response means 2, an automatic telephone response means 3, a remote security management server 4, a security control device 5, an entrance door 6, a user 7, and a mobile phone 8 possessed by the user 7. Consists of The mobile phone 8 possessed by the user 7 is connected to the automatic mail answering means 2 and the automatic telephone answering means 3 via the communication line 20. The automatic mail response unit 2 includes a personal information storage unit 10, a blank mail reception unit 11, a mobile phone confirmation unit 12, a reply mail transmission unit 13, a response mail reception unit 14, and a user authentication unit 15. The entrance / exit door 6 in the building is unlocked by remote operation by the remote security system 1 using this mobile phone.

  FIG. 2 shows a response between the mobile phone 8 of the user 7 and the mail automatic response means 2 of the remote security system 1 using the mobile phone. Here, the user 7 represents a plurality of employees who use the remote security system 1 using the mobile phone, and the mobile phone 8 is owned by a plurality of employees who use the remote security system 1 using the mobile phone. On behalf of mobile phones.

  The personal information storage unit 10 stores in advance the registered mail address 18 of the mobile phone 8 possessed by the registered user 7 and the registered telephone number 19 of the mobile phone 8. The personal information storage unit 10 stores in advance the set registered question phrase 26 and the registered answer phrase 17 registered by the user 7 with respect to the question phrase 26.

  The empty mail receiving unit 11 receives an empty mail 21 transmitted from the mobile phone 8 of the user 7 as indicated by an arrow A in FIG. The empty mail receiving unit 11 acquires the mail address 23 and the mobile phone number 24 of the mobile phone 8 from the empty mail 21. Then, the mobile phone confirmation unit 12 includes the registered mail address 18 and the registered mobile phone number 19 of the user 7 stored in the personal information storage unit 10, and the mail address 23 and the mobile phone number 24 of the transmitted mobile phone 8. Compare If the transmitted mail address 23 and the registered mail address 18 are the same, and the transmitted mobile phone number 24 and the registered mobile phone number 19 are the same, it is transmitted from the mobile phone 8 of the seven users. It is authenticated that the empty mail 21 is received. On the other hand, if at least one of them is not the same, it is determined that it is not the empty mail 21 transmitted from the mobile phone 8 of the seven users, and the empty mail 21 is ignored.

  When the mobile phone confirmation unit 12 authenticates that it is the empty mail 21 transmitted from the mobile phone 8 of the user, the reply mail transmission unit 13, as shown by the arrow B in FIG. A reply mail 22 including the phrase 26 and the telephone number 27 of the automatic telephone response means 3 is transmitted to the user 7. Then, the reply mail receiver 14 receives the reply mail 28 transmitted from the mobile phone 8 of the user 7 as indicated by an arrow C in FIG. This reply mail 28 includes a one-time ID 29 and a reply phrase 30. When the registered response phrase 17 stored in the personal information storage unit 10 and the returned response phrase 30 match, the user authentication unit 15 determines that the response mail 28 is from the user and authenticates the user. I do. On the other hand, if the registered response phrase 17 stored in the personal information storage unit 10 and the returned response phrase 30 do not match, it is determined that it is not the response mail 28 from the principal, and the personal authentication is not performed.

  FIG. 3 shows the response of the mobile phone 8 of the user 7 and the automatic telephone response means 3. The user 7 obtains the telephone number 27 of the automatic telephone response means 3 from the reply mail transmission unit 13, and makes a confirmation call 32 from the mobile phone 8 to the telephone number 27. The automatic telephone response means 3 compares the registered mobile phone number 19 stored in the personal information storage unit 10 with the mobile phone number 24 that has been dialed, and if they match, it is confirmed that the mobile phone 8 of the user 7 is present. . If the registered mobile phone number 19 does not match the mobile phone number 24 that has been dialed, it is determined that the mobile phone 8 is not 7 users.

  When the automatic telephone answering means 3 confirms that it is the mobile phone 8 of seven users, it uses the one-time ID 31 and the unique door code 16 displayed on the doorway 6 to be unlocked in the confirmation telephone 31. Ask person 7. The user 7 replies with a unique door code 16 displayed on the door 6 that is unlocked and the one-time ID 31 by a call on the mobile phone 8. The automatic telephone response means 3 obtains the one-time ID 25 from the reply mail transmission unit 13. Then, the one-time ID 31 answered by the user 7 is compared with the one-time ID 25 acquired from the reply mail transmission unit 13. Then, the automatic telephone response means 3 performs personal authentication when they match, and does not perform personal authentication when they are different.

  Further, the automatic telephone response means 3 confirms the position of the user 7 by inquiring the specific door code 16 displayed on the door 6 to be unlocked by the confirmation telephone 32. That is, in a building or facility having a plurality of rooms, each door 6 is assigned a door code 16 that is a unique ID code. The door code 16 is displayed on each door 16. This display is performed by, for example, a method of attaching a label printed with the door code 16 to the entrance door 6. The user 7 cannot obtain the door code 16 unless he / she goes to the door 6 in front of the door 6 to be unlocked.

  And if the remote security management server 4 authenticates that both the user authentication part 15 of the automatic mail response means 2 and the automatic telephone response means 3 are the person, the gateway corresponding to the door code 16 is sent to the security control device 5. The door 6 is unlocked. Thereby, it can prevent being mischievous by the outside person who acquired the lost personal authentication card.

  FIG. 4 shows one embodiment of the registered question phrase 26 stored in the personal information storage unit 10 and the registered answer phrase 17 corresponding thereto. The personal information storage unit 10 stores a plurality of sets of different registered question phrases 26 and registered answer phrases 17 corresponding thereto. For example, the registered answer phrase 17 is “Mimi” for the registered question phrase 26 “What is the name of the pet?”. Further, for example, the registered answer phrase 17 “Italian” is associated with the registered question phrase 26 “What is your favorite dish?”. Further, for example, the registered answer phrase 17 “Greece” is associated with the registered question phrase 26 “What country do you want to visit?”. The user authentication unit 15 randomly selects the registered question phrase 26 from the plurality of registered question phrases 26 and causes the reply mail transmission unit 13 to reply. Thereby, security can be secured even when the registered answer phrase 17 for the specific registered question phrase 26 leaks to another person or when the registered answer phrase 17 for the specific registered question phrase 26 is easy to guess.

  Further, the remote security management server 4 causes the user authentication unit 15 to select two or more registered question phrases 26 from the plurality of registered question phrases 26 according to the input security level, and causes the reply mail transmission unit 13 to reply. . For example, a registered question phrase 26 “What is your favorite dish?” And a registered question phrase 26 “What country do you want to visit?” Are selected, and both questions are answered. On the other hand, the personal authentication is performed only when the record reply phrase 17 is answered. Thereby, even when security needs to be improved due to security requirements, it can be easily handled.

  When the user 7 replies the answer phrase 30 to the registered question phrase 26 selected for the personal information storage unit 10, the remote security management server 4 stores the registered answer stored in the personal information storage unit 10. The phrase 17 is deleted and the user 7 is newly registered. For example, when the answer phrase 30 “Greece” is replied to the registered question phrase 26 “What country do you want to visit?”, Another answer phrase, for example, “Italy” is newly set as the registered answer phrase 17. It is stored in the personal information storage unit 10.

(Remote security method using mobile phone)
FIG. 5 is a flowchart showing the responses of the mobile phone 8 of the user 7 and the automatic mail response means 2 in the remote security method using the mobile phone 8. First, the mail address 23 and the mobile phone number 24 of the mobile phone 8 of the user 7 and the registered answer phrase 17 registered by the user with respect to the set registration question phrase 26 are stored (S1). Here, the user 7 refers to an employee who uses the remote security system 1 using the mobile phone 8. Then, when the empty mail 21 transmitted from the mobile phone 8 of a certain user 7 is received (S2), the mobile phone 8 of the user 7 by the registered mail address 18 and the registered mobile phone number 19 of the stored user 7 is stored. (S3). If it is not the mobile phone 8 of the seven users, the blank mail 21 is ignored and the process returns to S2, and if it is the mobile phone 8 of the seven users, the process proceeds to the next step (S4). A reply mail 22 including the ID 25, the registered question phrase 26, and the telephone number 27 of the automatic telephone answering system 3 is transmitted to the user 7 (S5). Then, the reply mail 28 is received from the mobile phone 8 of the user 7 (S6). This reply mail 28 includes a one-time ID 29 and a reply phrase 30. The answer phrase 30 is compared with the registered answer phrase 17 registered by the seven users, and authentication of the seven users is performed (S7). Then, the result of the personal authentication is stored (S8). The subsequent flow proceeds to X in FIG. 6 and Y in FIG.

  FIG. 6 is a flowchart showing the response of the user 7 to the mobile phone 8 and the automatic telephone response means 3 in the remote security method using the mobile phone 8. The user 7 calls the telephone number 27 of the automatic telephone answering system 3 using the mobile phone 8 (S9). By comparing the registered mobile phone number 19 with the registered mobile phone number 24, it is confirmed that it is the mobile phone 8 of seven users (S10). If it is not the mobile phone 8 of the seven users, for example, if the mobile phone 8 of the user hangs up with a message such as "the mobile phone you have called is not registered" Advances to the next step (S11). That is, the door code 16 displayed on the doorway door 6 to be unlocked and the one-time ID 25 is inquired (S12). The user 7 answers the door code 16 displayed on the door 6 that is unlocked and the one-time ID 31 in a telephone call (S13). Then, the one-time ID 31 answered by the user 7 is compared with the one-time ID 25 transmitted to the user by the reply mail 22 to authenticate the user (S14). The subsequent flow proceeds to Y in FIG.

  FIG. 7 is a flowchart showing the operation of the remote management server 4 in the remote security method using the mobile phone 8. It is confirmed that both the authentication of the reply mail 22 and the confirmation telephone 32 is the person (S15). If it is confirmed that both are seven users, the process proceeds to the next step, and if at least one of the seven users is not confirmed, the process returns to S2 (S16). And if it can confirm that it is both seven users, the door 6 corresponding to the door code 16 is unlocked (S17).

  In the remote security method using the mobile phone 8 described above, a plurality of sets of different registered question phrases 26 and registered answer phrases 17 corresponding thereto are stored, and the registered question phrases 26 can be selected at random from the plurality of registered question phrases 26. good. Further, two or more registered question phrases 26 may be selected from the plurality of registered question phrases 26 according to the input security level. Furthermore, the registered answer phrase 17 answered to the selected registered question phrase 26 may be deleted, and the user 7 may be registered as a new registered answer phrase 17.

  DESCRIPTION OF SYMBOLS 1 Remote security system by mobile phone, 2 Mail automatic response means, 3 Automatic telephone response means, 4 Remote security management server, 5 Security control device, 6 Doorway entrance, 7 User, 8 Mobile phone, 10 Personal information storage part, 11 Blank email reception unit, 12 mobile phone confirmation unit, 13 reply email transmission unit, 14 reply email reception unit, 15 user authentication unit, 16 door code, 17 registration reply phrase, 18 registration email address, 19 registration mobile phone number, 20 Communication line, 21 Blank mail, 22 Reply mail, 23 Mail address, 24 Mobile phone number, 25, 29, 31 One-time ID, 26 Registration question phrase, 27 (Automatic telephone response means) telephone number, 28 Reply mail, 30 Answer phrase, 32 confirmation phone.

Claims (10)

A remote security system for unlocking doorways in buildings by remote control,
A personal information storage unit for storing an email address of a mobile phone possessed by the registered user and an answer phrase registered by the user for the set question phrase;
A blank email receiver that receives blank email sent from the user's mobile phone;
A mobile phone confirmation unit for confirming that the mobile phone is the user's own mobile phone based on the registered email address of the user stored in the personal information storage unit;
A reply mail sending unit for sending a reply mail containing a one-time ID, a question phrase, and a telephone number of an automatic telephone response means to the user;
A reply mail receiving unit that receives a reply mail that includes a one-time ID and a reply phrase that is replied from the user's mobile phone;
A mail automatic response means comprising: a user authentication unit that authenticates a person by comparing a response phrase that has been answered and a registered answer phrase;
When a user makes a call to the telephone number of the automatic telephone answering means using a mobile phone, the user asks the one-time ID and the unique door code displayed on the doorway to be unlocked, and the user's identity from the answer Automatic telephone response means for authentication and location confirmation;
When both the user authentication unit of the automatic mail response means and the automatic telephone response means authenticate themselves, a remote security management server that causes the security control device to unlock the entrance door corresponding to the door code,
A remote security system using a mobile phone, comprising:   2. A remote security system using a mobile phone according to claim 1, wherein the personal information storage unit stores the mobile phone number of the user of the system in association with the mail address, and the automatic telephone response means includes the personal information storage unit. A mobile phone remote security system for confirming that the mobile phone is the user's own mobile phone by comparing the registered mobile phone number stored in the mobile phone number and the mobile phone number that has been dialed.   The remote security system using a mobile phone according to claim 1 or 2, wherein the personal information storage unit stores a plurality of sets of different question phrases and answer phrases corresponding thereto, and the user authentication unit includes a plurality of question phrases. A remote security system using a mobile phone, wherein a question phrase is randomly selected from and a reply mail transmission unit is made to reply.   The remote security system using a mobile phone according to any one of claims 1 to 3, wherein the remote security management server receives two or more question phrases from a plurality of question phrases in the user authentication unit according to the level of security inputted. A remote security system using a mobile phone, wherein a question phrase is selected and a reply mail transmission unit is made to reply.   The remote security system using a mobile phone according to any one of claims 1 to 4, wherein the remote security management server deletes the registered answer phrase for the selected question phrase with respect to the personal information storage unit, A remote security system using a mobile phone, which allows a user to register a new answer phrase. A remote security method for unlocking doorways in buildings by remote control,
Storing an email address of a mobile phone possessed by the registered user and an answer phrase registered by the user for the set question phrase;
Receiving a blank email sent from the user's mobile phone;
Confirming the user's own mobile phone with the stored user's registered email address;
Sending a reply email containing a one-time ID, a question phrase, and a telephone number of an automatic telephone answering system to the user;
Receiving a reply e-mail returned from the user's mobile phone and including a one-time ID and an answer phrase;
A step of authenticating the person by comparing the answer phrase that has been answered and the registered answer phrase,
When a user calls the telephone number of the automatic telephone answering system using a mobile phone, he / she asks about the unique door code displayed on the doorway to be opened and the one-time ID, and authenticates the user from the answer. And a step of confirming the position;
A step of unlocking the entrance door corresponding to the door code when the identity is confirmed by both the e-mail and telephone authentication,
A remote security method comprising:   7. The remote security method using a mobile phone according to claim 6, wherein the mobile phone number of the user is stored in association with an e-mail address, and the user calls the phone number of the automatic answering system by the mobile phone. And a stored mobile phone number stored and the mobile phone number that has been dialed are compared to confirm that the mobile phone is the user's own mobile phone.   The remote security method using a mobile phone according to claim 6 or 7, characterized in that a plurality of sets of different question phrases and answer phrases are memorized and a question phrase is selected at random from the plurality of question phrases. Remote security method using mobile phone.   The remote security method using a mobile phone according to any one of claims 6 to 8, wherein two or more question phrases are selected from a plurality of question phrases according to an input security level. Remote security by telephone.   The remote security method using a mobile phone according to any one of claims 6 to 9, wherein the answer phrase registered for the selected question phrase is deleted, and the user is made to register a new answer phrase. A remote security method using a cellular phone.

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