GB2489247A

GB2489247A - Method for secure communication of machine-readable encoded data

Info

Publication number: GB2489247A
Application number: GB201104779A
Authority: GB
Inventors: Marcus James Roberts; Allan John Chaplin
Original assignee: BIG BOX SOFTWARE Ltd
Current assignee: BIG BOX SOFTWARE Ltd
Priority date: 2011-03-21
Filing date: 2011-03-21
Publication date: 2012-09-26
Also published as: GB201104779D0

Abstract

A method of secure communication of machine-readable encoded data comprising the steps of encrypting 13a a data set at a first location 1 by a stored encryption/decryption key, generating 14a a machine-readable code at that location, the code containing the encrypted data set encoded in the matrix of a quick-response (QR) code, and transporting or transmitting 15a the QR code to a second location 2. At the second location the code is scanned 26, decoded 24b and decrypted 23b with use of the same key to recover the data set and this data set is then reproduced 22b, preferably on a display. The key may be communicated from the first location to the second location, e.g. by electrical or electromagnetic means. The QR code may be displayed on a screen or printed, e.g. on a label.

Description

METHOD OF SECURE COMMUNICATION OF MACHINE-READABLE ENCODED DATA

The present invention relates to a method of secure communication of machine-readable encoded data and to a device for use in such a method.

Scannable codes based on geometric patterns exist in various forms and are employed for the purpose of presenting coded data in a form able to be read and interpreted by machine, but not directly by the human eye. Useful information intended to be relatively confidential or, at least, concealed from ready recognition can thus be provided on goods for sale or on other articles entering the public arena or otherwise accessible without constraint. The most widely used codes of that kind are bar codes, in which data is coded in the form of parallel lines of varying thickness and spacing. Other forms of codes include quick-response codes, which are composed of matrices of squares in contrasting tones, in particular black and white. The relatively large number of matrix squares able to be accommodated in a code panel of small size allows the code to contain a larger amount of information by comparison with, for example, a bar code. The information can be coded in mutually orthogonal directions, which further increases the amount of information able to be accommodated. The code, which can incorporate a degree of redundancy to accommodate error correction, is scannable to yield a bit stream of binary digits. This is readily decodable for retrieval of the embedded data, whether numerical, textual or a combination of both.

Such quick-response codes can be read, as in the case of bar codes, by dedicated scanners or other, suitably programmed scanners, including those frequently incorporated in portable transceivers, such as mobile telephones equipped with suitable code recognition and decoding software. Consequently, although an individual might not, unaided, be able to extract information from a quick-response code, this can be easily achieved with use of an appropriate scanner. Quick-response codes are thus inherently insecure and in certain circumstances, particularly in the case of use of quick-response codes containing information intended to be read only by specific or authorised persons, confidentiality and security are compromised. In the end result, quick-response codes have to be confined to situations in which there are no security or related risks connected with decoding of the codes. As soon as a quick-response code leaves the immediate jurisdiction or control of the party responsible for creating or applying the code, the data content of the code is effectively accessible to any interested party.

There is therefore a need for a procedure for secure communication of machine-readable codes, particularly quick-response codes, so that data embedded in the codes cannot be retrieved by unauthorised parties even when equipped with readers capable of reading the codes. Such a procedure has practical application especially in situations where, for example, such codes are applied to articles or goods leaving the direct control of the party or parties applying the codes.

According to a first aspect of the present invention there is provided a method of secure communication of machine-readable encoded data, comprising the steps of encrypting a data set at a first location by means of an encryption/decryption key, generating a machine-readable code at the first location, the code containing the encrypted data set encoded in the matrix of a quick-response code, transporting or transmitting the quick-response code to a second location, scanning the quick-response code and decoding the scanned code at the second location by scanning and decoding means, decrypting the decoded code by decrypting means storing the key so as to recover the data set and reproducing the recovered data set in optical or acoustic form at the second location.

Such a method utilises a conventional quick-response code with the indicated advantage of high information content, but without an unfettered capability of interpretation of the code. The key employed for encryption of the code at the first location, for example a fixed or mobile equipment position, is made available at the second location, for example another fixed or mobile equipment position, to enable decryption of the scanned code after transport or transmission -depending on the form in which the code is generated -to the second location. Consequently, the data set after scanning and decoding at the second location cannot be translated into comprehensible form by anybody other than the user of scanning and decoding means and associated decrypting means in which the key is stored. The authorisation of the user to access the data set can thus be granted under the control of a party generating the code at the first location. As an example of deployment of the method in practice the generated quick-response code can be applied externally to or embedded electronically in computer equipment by a supplier, so that when the code is later scanned, decoded and decrypted it reveals confidential data, for example a password and/or enabling or commissioning instructions, to and only to a designated recipient furnished with the decryption key. The equipment is thus safeguarded against use by unauthorised third parties.

The method can include a preliminary step of generating the encryption/decryption key, which can thus be specific to a particular quick-response code and the transport or transmission of that code. In one option, such a key can be generated at the first location, thus by, for example, the party generating the quick-response code, and communicated to the second location separately from the code. The separate communication ensures that the key is isolated from the code and cannot be readily acquired by an unauthorised third party. The communicated key can, on receipt, be entered into a memory of the decrypting means at the second location so that a facility is available at the second location, before or after receipt of the quick-response code itself, to enable recovery of the data set from the code.

In another option, the key is generated at a location different from the first location and communicated to the first location. The key can thus be imported at the first location from an outside source when this is appropriate. If the location different from the first location is the second location, an intended recipient of the quick-response code can exercise individual control from the outset over recovery of the data set from the code. The key in that case can be, for example, a private key normally confidential to the recipient. In this option, the imported key is preferably stored in data encrypting means at the first location so as to then be available for data encryption prior to generation of the quick-response code.

Communication of the key to or from the first location can be carried out electrically, electronically, electromagnetically, optionally or acoustically, especially by radio frequency such as used by transceivers in the nature of mobile telephones or electronically in the context of telecommunications via the Internet. The key transmission procedure can advantageously be assimilated to other aspects of the method if the key itself is encoded in the matrix of a quick-response code different from that containing the data set and if the communicated key encoded in that form is then scanned and decoded at the destination location to capture the key. The code containing the key can thus be processed in similar manner to the code containing the data set, subject to any essential security considerations relating to separation of the transmission of the code with the key and the code with the data set.

Communication of the quick-response code containing the data set to the second location is preferably carried out, in one example of the method, by transport to the second location of the code in a physical form generated at the first location. The code. in physical form can, for example, be applied to a parcel, an item of goods or another article which is then delivered to the second location, where scanning of the code can take place. Such a physical form can be a print, which can be printed on a label, packaging or even directly on an article to be transported. In another example of the method, the code containing the data set is generated in non-physical form, for example in electronic form, and transmitted in that form to the second location, for example electrically, electronically, electromagnetically, optically or acoustically. The generated code is in that case output at the first location as a signal train representing the code and is reproducible at the second location as a scannable image of the code. It is equally possible to combine the two methods, thus generation of the code in both physical and non-physical forms and communication of both forms to the second location.

The scanning and decoding means and the decrypting means at the second location can be conveniently incorporated in a mobile telephone or other item of equipment which has a fixed position or is portable. In the case of portability, the second location is then the instantaneous position of the equipment. The recovered data set is preferably reproduced in optical and/or acoustic form, for example as a display on a display screen and/or as a synthesised voice output, so that a party at the second location can read or hear, for example, a message in text form or as speech originating from the first location and extracted from the code containing the data set.

According to a second aspect of the invention there is provided a device for use in performing a method according to any one of the preceding claims, comprising data encrypting/decrypting means storing at least one encryption/decryption key for encrypting and decrypting data sets, code generating means for generating machine-readable codes, each generated code containing a data set encrypted by the key and encoded in the matrix of a quick-response code, scanning and decoding means for scanning quick-response codes containing encrypted data sets and for decoding the scanned codes to recover the encrypted data sets for decryption by the encrypting/decrypting means, and data reproducing means for reproducing recovered and decrypted data sets.

Such a device can be used at either or each of the first and second locations in the context of performance of the method. If used at both locations, the method can be performed bidirectionally, in which case the first location and second location are identifiable with, respectively, the origin and the destination of the code on each occasion of code communication.

The device preferably comprises key generating means for generating at least one encryption/decryption key, whereby the method can be performed with autonomous key generation rather than rely on importation of a key. In that case it can be advantageous if the code generating means is operable to encode the generated key in the matrix of a quick-response code different from a code containing a data set. Consequently, the key can be provided and processed by the same code generating means employed for the codes with data sets. The device preferably also includes transmitting means for transmitting the generated codes, including codes containing keys when such are generated by the device. The transmitting means is preferably operable to transmit electrically, electronically, electromagnetically, optically or acoustically.

In one preferred embodiment the device includes printing means for printing the codes containing data sets so that the codes can be produced in physical form, when this is appropriate to the specific method procedure, by the device itself without resort to an external printer. The data reproducing means is preferably operable to reproduce recovered and decrypted data sets in optical and/or acoustic form. Accordingly, the device can include a display screen to optically reproduce the recovered and decrypted data sets, which provides a user of the device with ready access to the data in, for example, readable form. Additionally or alternatively, the data reproducing means can comprise voice synthesising means to acoustically reproduce recovered and decrypted data sets. In that case, the user can hear a message analogously to normal use of a mobile telephone.

An example of the method and an embodiment of the device of the present invention will now be more particularly described with reference to the accompanying drawings, in which: Fig. I is a schematic view of a typical format of a quick-response code employed in an example of the method of the invention; and Fig. 2 is a schematic block diagram of two telecommunications devices each embodying the invention and each usable in connection with performance of a method exemplifying the invention, the diagram showing device components representative of steps or stages of the method.

Referring now to the drawings there is shown in Fig. 1 part of a quick-response code A of the kind described in the introduction, in particular a two-dimensional panel composed of a matrix of squares B contrastingly rendered in black and white to encode a message, which can be textual, numerical or both. The panel, i.e. the code, can be scanned by a suitable optical scanner to generate a bit stream of binary digits which differ in sequence corresponding with the sequence of differing tones of the matrix squares scanned in horizontal or vertical direction, the digits being decodable to recover the message. Such codes and the procedure for decoding are well-known and accordingly not described in further detail.

Fig. 2 shows steps in a method for secure communication of a quick-response code of this kind, for example the code A, and two devices 10 and 20 usable for that purpose. For ease of understanding, the two devices 10 and 20 are shown in identical form, albeit in mutually inverted relationship to facilitate illustration of method steps, but the devices used in the method can be of quite different construction provided only they include features appropriate to performance of the method. The two devices 10 and 20 can thus be, for example, two mobile telephones with suitable hardware and software, a mobile telephone and a personal computer, two computers, two mobile telephones in combination with two computers, or other equipment. The device 10 is disposed in a first location I and the device 20 in a second location 2, signified in Fig. 2 by two planes respectively above and below a median dashed line. Each location can be a fixed position if the device is a fixed station, for example computer equipment with usual peripherals, or a movable position if the device is portable, as in the case of a mobile telephone or portable computer, for

example laptop.

In the illustration in Fig. 2 the communication capability is bidirectional. For easier representation of aspects of the method, communication from the plane or location 1 to the plane or location 2 is represented by solid lines and that in opposite sense by dashed lines. However, this is merely by way of example and it will be evident from the following description that other forms and directions of communication are possible. These include communication to and from outside sources, particularly to and from further such devices or equipment.

The device 10 comprises message generating means 11, display means 12, encrypting/decrypting means 13, encoding/decoding means 14 suitable for constructing and deconstructing quick-response codes, transmitting/receiving means 15 and scanning means 16. The device 10 is here represented by a combination of a mobile telephone and a computer, in which the scanning means is respective to the mobile telephone and the display means 12 is in part a display of the mobile telephone and in part a display of the computer.

The message generating means 11 serves for generating a set of data, here in the form of a message, and typically comprises a keyboard or keypad with discrete keys or pads or a corresponding touch-sensitive panel with individual touch zones. Such a panel can be integrated in the display means 12 if the latter has contact-recognition zones and an associated signal generating capability. The keyboard/keypad or panel preferably has an alpha-numeric input capability, i.e. a capability of input of signals representing all of the numerals 0 to 9 and all of the letters A to Z; the input of letters can optionally be based on numeral combinations.

The display means 12 preferably comprises a liquid-crystal display screen or other form of display screen conventionally employed in electronic equipment, including portable telecommunications devices, and is depicted with divisions into a display zone 12a for output messages created by the message generating means, a display zone 12b for input messages received from the device 20 or other equipment, and a display zone 12c for quick-response codes similarly received from the device 20 or other equipment. The display zone 12a and 12b are merely notional designations of two display capabilities of the display means 12, which can display various incoming and intended outgoing messages with textual and/or numerical content as well as user prompts, acknowledgements and other internally generated communications. The display zone 12c, however, is required to display a graphical image of variable composition, i.e. a quick-response code, and to be scannable for recordal of the image, for which reason it is physically separate from, at least, the scanning means 16.

The display means 12 can be supplemented by audio means for acoustical output of messages, particularly received messages, by voice synthesis as in the case of a telephone.

The encrypting/decrypting means 13 serves for encrypting generated messages intended for output and decrypting received messages and is depicted with notional division into an encrypt zone 13a and decrypt zone 13b. The encoding/decoding means 14 serves for encoding an encrypted message into the format of a quick-response code matrix, thus for generating a quick-response code A, and for decoding a received quick-response code A. Accordingly, it is depicted with notional division into an encode zone 14a and a decode zone 14b. The encrypting/decrypting means 13 and encoding/decoding means 14 can, in practice, be embodied as respective parts of programmable software of the device, but can equally well be individual components.

The transmitting/receiving means 15 serves for transmitting generated quick-response codes intended for output and for receiving quick-response codes transmitted from the device 20 or another source and accordingly is depicted as a transmit zone iSa and receive zone I Sb. Transmission and reception can be by way of, for example, radio frequency as in the case of mobile telephones, portable computers and the like or signal transmission on line conductors in the case of hard-wired equipment, included non-portable computers. Instead of or in addition to the transmit zone iSa the device can include printing means for printing a generated quick-response code, for example on a label which can be attached to an article. The code in that case is created in physical rather than electrical or signal form and physically transported from the first location I to the second location 2.

Finally, the scanning means 16 serves for scanning quick-response codes A received from the device 20 or another source and for that purpose comprises an optical reader able to record and store the image of the code and convert the pattern of contrasting zones in the code matrix into a binary code for decoding in the encode zone 14b of the encoding/decoding means. The decoded code yields an encrypted message which can be decrypted in the decrypt zone 1 3b of the encrypting/decrypting means 13 and forwarded for display in the received-message display zone 1 2b of the display means 12.

The operation of the encrypting/decrypting means 13 is on the basis of a stored encrypt/decrypt key and explained further below. The encrypting/decrypting means 13, as other components of the device, includes an erasable memory for selectable or automatic storage of input data.

As mentioned above, in this example the device 20 is of identical construction to the device 10 and accordingly has the same components, which are denoted by reference numerals corresponding with those employed for the components of the device 10, but incremented by 10, thus 11 incremented to 21, 12 to 22, 12a to 22a, 12b to 22b and so forth. Accordingly, repetition of the description of the construction and purpose of the components of the device 20 is not necessary. As also already mentioned, the sequence of the components of the device 20 is illustrated with inversion by comparison with that of the components of the device 10.

In performance of a method exemplifying the invention, particularly with use of the devices and 20, for secure transmission or transport of machine-readable encoded data in the form of a scannable quick-response code A, initially a data set to be communicated is generated by the message generating means of the device 10 at the first location 1. The data set can be, for example, a simple message in text, perhaps with a user name and password for an item of equipment or log-in site to be accessed by a recipient of the message, or a considerably more complex communication including operating and control instructions or other technical information. The sole criterion is that the data set, which in the present example is a message, is to be kept confidential to the communicating parties.

The generated message is, in this instance, displayed in the display zone 12a of the display means 12 to assist the composition procedure and then passed for encryption to the encrypt zone I 3a of the encrypting/decrypting means 13. Encryption is carried out with use of an encryption/decryption key comprising a stored encryption and decryption algorithm selected from a standard encryption library. The same key is stored in the encrypting/decrypting means 23 of the device 20 and can be a symmetric key shared by both parties concerned, i.e. the users of the devices 10 and 20, or half of an asymmetric key pair, in which a private key remains confidential to the sender and a public key is shared by the sender with the recipient. Procedures for key selection in specific circumstances are indicated further below.

The encrypted message is now encoded into standard quick-response code format in the encode zone 14a of the encoding/decoding means 14, thus to create a code of the kind depicted in Fig. 1, and transmitted by the transmit zone 1 5a of the transmitting/receiving means 15. Transmission can be by way of various carriers, including wire conduction of electrical signals and electromagnetic, light and sound waves. In one particularly convenient method the code is sent by electronic mail on the Internet so as to be reproduced in high definition within a typical Internet transmission time. The transmitted quick-response code is exclusively addressed to and received by the device 20, specifically the receive zone 25a of the receiving/transmitting means 25 of that device, at the second location 2. This can be at any distance from the location 1, including in a different country. The received code is displayed as an electronically generated image in the display zone 22c of the display means 22, for example the screen of a computer. The displayed code is now scanned by the scanning means 26 to record and store the code image and thus capture the data represented by the specific contrasting zone pattern of the code matrix. Binary code signals representing the captured data are passed to and decoded by the decode zone 24b of the encoding/decoding means 24 to recover the encrypted message, which is then decrypted in the decrypt zone 23b of the encrypting/decrypting means 23 with use of the stored key and finally displayed in the display zone 22b of the display means 22. The display zone 22b is in this instance, for example, the screen of a mobile telephone which incorporates the scanning means 26 and also software representing the encoding/decoding means 22 and decrypting/encrypting means 23. The device 20, like the device 10, can take various forms, thus a single item of appropriately configured equipment or t*o or more items of co-operating or co-operable equipment.

Since storage of the encryption/decryption key is exclusive to the two devices 10 and 20, only the user of the device 20 has the facility of accessing the message, in comprehensible form, delivered by or from the device 10. Consequently, it is of no concern if the quick-response code itself enters the public arena or is otherwise capable of overt or covert access. ln the just-described example the communication link between the devices provides transmission and reception of the quick-response code in non-physical form, but if the code is generated in physical form, for example a printed label applied to an object at the first location, the object is physically transported to the second location where the label can be scanned by the scanning means 26 without a requirement for use of receiving means or code display means as intermediate stages. This can be an effective procedure for, for example, transporting equipment, parcels and other articles intended for a specific recipient at the second location, i.e. destination.

The encryption/decryption key central to unlocking or recovering the originally generated message after transmission or transport can be selected by the user of the device 10 or imported from an external source, including the user of the device 20. If selected by the user of the device 10, the key is communicated to the user of the device 20 by suitable means, but preferably a channel separate from that employed for communication of the quick-response code containing the message. If, on the other hand, the key originates with the user of the device 20 an additional overlay of security is afforded to the recipient of the message. Selection of the key by the user of the device 20 and communication to the user of the device 10 can be by various procedures, but conveniently by a procedure analogous to that involved in communicating the encrypted message encoded as a quick-response code. Accordingly, in a preferred procedure as indicated by the dotted progression in Fig. 2 an encryption code is generated at the device 20 by way of the message generating means 21, which is furnished with suitable operating commands and access to a standard encryption code library, encoded into a quick-response code format in the encode zone 24a of the encoding/decoding means 24 and transmitted by the transmit zone 25a of the transmitting/receiving means 25 to the device 10. At the device the code containing the key is received by the receive zone lSb, displayed as an image in the display zone 12c, scanned by the scanning means 16 and decoded in the decode zone 14b to recover the encrypted key, which is then stored in the encrypting/decrypting means 13 at the choice of the user 10 and under the prompt of an enquiry displayed by the display means 12. The stored key is then available for use in a succeeding procedure for secure transmission of useful data -embodied as an encrypted message in quick-response code format -from the device 10 to the device 20.

The method can be readily expanded to provide secure communication of encoded data to multiple recipients, the only requirement being possession of the decryption key in stored form in compatible devices operated or controlled by the intended recipients. The method is advantageous in any circumstances where confidential data is to be securely communicated without concern for the otherwise non-secure transmission or transport of a code, namely a quick-response code, in which the data is embedded.

Claims

CLAIMS1. A method of secure communication of machine-readable encoded data, comprising the steps of -encrypting a data set at a first location by means of an encryption/decryption key, -generating a machine-readable code at the first location, the code containing the encrypted data set encoded in the matrix of a quick-response code, -transporting or transmitting the quick-response code to a second location, -scanning the quick-response code and decoding the scanned code at the second location by scanning and decoding means, -decrypting the decoded code by decrypting means storing the key so as to recover the data set and -reproducing the recovered data set at the second location.
2. A method according to claim 1, comprising a preliminary step of generating the encryption/decryption key.
3. A method according to claim 2, wherein the key is generated at the first location and communicated to the second location separately from the quick-response code.
4. A method according to claim 3, comprising the step of storing the communicated key in the decrypting means at the second location.
5. A method according to claim 2, wherein the key is generated at a location different from the first location and communicated to the first location.
6. A method according to claim 5, wherein the location different from the first location is the second location.
7. A method according to claim 5 or claim 6, comprising the step of storing the communicated key in data encrypting means at the first location.
8. A method according to any one of claims 3 to 7, wherein the key is communicated electrically, electronically, electromagnetically, optically or acoustically.
9. A method according to any one of claims 3 to 8, wherein the key is encoded in the matrix of a quick-response code different from that containing the data set and the communicated key encoded in that form is scanned and decoded at the location receiving the transmission to capture the key.
10. A method according to any one of the preceding claims, wherein the code containing the data set is generated in physical form at the first location and transported to the second location.
11. A method according to claim 10, wherein the physical form is a print.
12. A method according to claim 11, wherein the print is applied to a label, to packaging or to an article to be transported.
13. A method according to any one of the preceding claims, wherein the code containing the data set is generated in non-physical form and transmitted in that form to the second location.
14. A method according to claim 13, wherein the code containing the data set is transmitted electrically, electronically, electromagnetically, optically or acoustically.
15. A method according to any one of the preceding claims, wherein the scanning and decoding means and decrypting means are incorporated in a mobile telephone.
16. A method according to any one of the preceding claims, wherein the recovered data set is reproduced in optical or acoustic form at the second location
17. A method according to any one of the preceding claims, wherein the recovered data set is reproduced as a message in text form.
18. A device for use in performing a method according to any one of the preceding claims, comprising data encrypting/decrypting means storing at least one encryption/decryption key for encrypting and decrypting data sets, code generating means for generating machine-readable codes, each generated code containing a data set encrypted by the key and encoded in the matrix of a quick-response code, scanning and decoding means for scanning quick-response codes containing encrypted data sets and for decoding the scanned codes to recover the encrypted data sets for decryption by the encrypting/decrypting means, and data reproducing means for reproducing recovered and decrypted data sets.
19. A device according to claim 18, comprising key generating means for generating at least one encryption/decryption key.
20. A device according to claim 19, wherein the code generating means is operable to encode the generated key in the matrix of a quick-response code different from those containing data sets.
21. A device according to any one of claims 18 to 20, comprising transmitting means for transmitting codes.
22. A device according to claim 21, wherein the transmitting means is operable to transmit electrically, electronically, electromagnetically, optically or acoustically.
23. A device according to any one of claims 18 to 22, comprising printing means for printing the codes containing data sets.
24. A device according to any one of claims 18 to 23, wherein the data reproducing means is operable to reproduce the recovered and decrypted data sets in optical and/or acoustic form.
25. A device according to claim 24, wherein the data reproducing means comprises a display screen to optically reproduce the recovered and decrypted data sets.
26. A device according to claim 24 or claim 25, wherein the data reproducing means comprises voice synthesising means to acoustically reproduce the recovered and decrypted data sets.