RU2611991C2 - Crum module and image forming apparatus for authentication and communication and methods therefor - Google Patents

Abstract

FIELD: information technology; image forming apparatus.

SUBSTANCE: invention relates to authentication of imaging device. Method comprises forming first data determining integrity relative to first data by means of a main controller installed on main housing of imaging device, for authentication with a CRUM module. Method comprises transmitting by main controller to CRUM module a first signal, which includes first data and first data for determining integrity. Integrity of first signal is tested via CRUM module using first data of determining integrity. Method includes forming by CRUM module second data for determining integrity using second data which must be transmitted to main controller, and first data for determining integrity in response to integrity of verified first signal. Method includes transmitting by CRUM module a second signal, which includes second data and second data for determining integrity of main controller.

EFFECT: technical result consists in reduction of errors of communication between flow control unit and image forming apparatus.

17 cl, 29 dwg

Description

1. The technical field to which the invention relates.

[0001] Embodiments of the disclosure herein relate to a CRUM module and an image forming apparatus for authentication and communication, and methods for doing this, and more particularly, a module for monitoring user replaceable blocks (CRUM) and an image forming apparatus for authentication and communications to determine whether or not the data is integral, using integrity determination data in the communication process, and to a method for this.

2. The level of technology

[0002] As computers become more widespread, the speed of distribution of computer peripherals also increases. Computer peripherals include imaging devices, for example, printers, faxes, scanners, copiers, and multifunction printers.

[0003] Image forming apparatuses may use ink or toner to print images on paper. Ink or toner is used every time an image forming operation is performed, and therefore is completely consumed when used for a longer time than a predetermined period of time. In this case, the unit in which ink or toner is stored must be replaced. Such parts or components that are replaceable during use of the image forming apparatus may be defined as consumable blocks or replaceable blocks. For convenience of explanation, they are referred to as consumables in this document.

[0004] In addition to these units, which must be replaced due to depletion of ink or toner, as explained above, there are also consumable units having characteristics that change when the units are used for a longer period of time, and are therefore replaced in order to achieve satisfactory print quality. Consumables include interchangeable color toner for developing machines and parts such as intermediate transfer belts.

[0005] In the case of laser imaging devices, electrical units, intermediate units or stabilizing units can be used in which various types of rollers and belts used in each unit can wear out or reduce their effectiveness when used for a period exceeding the service life . Accordingly, image quality can be significantly reduced. The user must replace each component, i.e. each consumable unit in an appropriate replacement period so that the printing operation can be performed so as to form clear images.

[0006] In order to more efficiently manage the consumable units, the storage devices may be attached to the consumable units in order to exchange information with the housing of the image forming apparatus.

[0007] In other words, it is possible to record various usage information, such as the number of printed sheets of paper, the number of printed dots and the period of use, in the storage device of the expendable unit for time management in order to replace the expendable unit.

[0008] As an example, large organizations, such as government agencies, universities, and organizations, use print management services (MPS) to manage multiple imaging devices with simplicity. The service of providing integrated solutions using MSP allows you to provide functions for calculating the costs of using supplies for each group or each user and their corresponding payment, as well as functions for checking the terms of use of supplies and ordering supplies before they wear out. Such functions may be provided based on accurate usage information for consumable units and materials.

[0009] To control this information, the controller provided in the housing of the image forming apparatus and the storage device provided in the consumable unit exchange data with each other. However, there are many variables in the communication process. For example, an attack may occur by a hacker who is trying to control a controller or storage device for malicious purposes.

[0010] In addition, interruption due to noise may occur, caused for example by an electronic circuit or an electric motor provided in the image forming apparatus. Unexpected events can occur, such as the penetration of foreign substances into the connecting part between the main body and the consumable unit of the imaging device, disconnection due to vibration during operation and / or the use of an electrical interference signal through the connecting part.

[0011] Transmitted data may vary due to these variables. For example, when the task is completed, the consumable unit can transfer information such as the number of pages printed, the number of dots and the remaining amount of toner to the controller and copies the information to the non-volatile memory of the controller. When reading data as an incorrect value, for example, such as 0xFFFFFFFF, there is a risk that the controller may perceive that the resource of the corresponding consumable unit has been exhausted. In this case, the consumable unit can no longer be used.

[0012] In addition, the consumable unit of the image forming apparatus may have a structure that can be removable. The storage device of the consumable unit is usually not accessed, and only the storage device of the image forming apparatus is used during the printing operation in the image forming apparatus due to, for example, vibration of the electric motor and noise in the circuit that may occur during operation. Thus, communication between the storage device of the consumable unit and the image forming apparatus can be performed only in limited periods, for example, when the expendable unit is installed in the image forming apparatus, so that the storage device of the expendable unit and the storage device of the image forming apparatus are synchronized with each other, or when the expendable the unit is updated for changes after the printing operation is completed, and the electric motor is stopped.

[0013] Since there may be a significant amount of data stored and managed in the consumable unit, various additional functions may be required, resulting in a long communication time. Accordingly, when the consumable unit is replaced during communication, problems may occur. As an example, information on the use of consumable units and materials of the consumable unit 1 indicates, for example, 100 printable pages, 200 output points and 300 actuations of the electric motor, and information on the use of consumable units and materials of the consumable unit 2 indicates, for example, 200 printable pages, 300 output points and 400 actuations of the electric motor. In this exemplary case, if the consumable unit 1 is installed in the image forming apparatus, the consumable unit 1 may synchronize with the storage device and the image forming apparatus data. If the consumable unit 1 is replaced by the consumable unit 2 during the synchronization process, i.e. only the data of 100 printed pages and 200 output points of the expendable unit 1 is stored in the storage device of the image forming apparatus, and then the expendable unit 1 is replaced by the expendable unit 2, authentication can be performed again. After that, the data 400 actuating the electric motor can be copied to the storage device of the imaging device. As a result, the storage device of the image forming apparatus indicates, for example, 100 printed pages, 200 output points and 400 actuations of the electric motor, which are not correct values. In this exemplary case, if the consumable unit 2 is updated for changes after the printing operation is completed in the image forming apparatus, data in 100 printed pages and 200 output points stored in the memory of the image forming apparatus can be stored in the consumable unit 2, while the actual data of the consumable unit 2 indicate 200 printable pages and 300 output points. When the printed page becomes 100 instead of 200, the corresponding consumable unit has incorrect data values and, therefore, can cause problems.

[0014] In addition, the image forming apparatus can have and use multiple consumable units in one channel based on an interface integrated circuit (I2C), wherein consumable units can be classified by the slave address in the I2C channel. In this case, if the slave address is modified to the identifier of another consumable unit due to some temporary problems, incorrect data may be stored in the storage device of another consumable unit.

[0015] Additionally, as regards a consumable unit whose life has expired, the hacker may attempt to reset user information on consumable units and materials, for example, to a value of “0” for malicious purposes, in order to reuse the consumable unit improperly. Accordingly, the user may try to use a consumable unit whose resource has been exhausted, which causes problems such as a failure of the imaging device or a decrease in resolution, and the user may not be provided with accurate information regarding consumable units, and in addition, the integrated solutions service may not be available due to MPS problems caused by incorrect information of consumables and materials.

[0016] Accordingly, a technology is required that effectively determines communication errors between the consumable unit and the image forming apparatus in order to strive to ensure data security.

SUMMARY OF THE INVENTION

[0017] Additional aspects and / or advantages are set forth in part in the description that follows, and in part are obvious from the description, or can be recognized through the practical use of the invention.

[0018] An aspect of exemplary embodiments is associated with a CRUM module and an image forming apparatus for ensuring communication security using integrity determination data, as well as a communication method for this.

[0019] An image forming apparatus according to an exemplary embodiment includes a main body that includes a main controller capable of controlling the operations of the image forming apparatus, a consumable unit that is installed in the main body with the ability to exchange data with the main controller, and a monitoring module user-replaceable blocks (CRUM), which is provided in the consumable block and stores information regarding the consumable block, and the main controller and CRUM module in exchange data if authentication succeeds, while authentication is performed through a plurality of authentication processes, and integrity determination data, which are generated by reflecting previous integrity determination data, is used in at least two authentication processes from a plurality of authentication processes.

[0020] The main controller and the CRUM module can generate final integrity determination data by cumulatively reflecting all integrity determination data transmitted or received in previous authentication processes in the final authentication process from a plurality of authentication processes.

[0021] The main controller and the CRUM module can transmit / receive a signal including integrity determination data during an authentication process to generate a session key and in an authentication process to verify compatibility from a plurality of authentication processes.

[0022] The main controller and the CRUM module may perform at least one authentication process between the authentication process to generate the session key and the authentication process to verify compatibility.

[0023] When the authentication process for generating the session key begins, the main controller can transmit a signal including the first data and the first integrity determination data to the CRUM module, and the CRUM module can generate the second integrity determination data using the second data and the first integrity determination data and transmit a signal including second data and second integrity determination data to the main controller, and each of the first data and second data may include data communicating data with a session key to generate a session key.

[0024] When the authentication process for verifying compatibility begins, the main controller may generate third integrity determination data using third data, first integrity data and second integrity data, and transmit a signal including third data and third integrity determination data to CRUM -module, CRUM-module can generate fourth integrity determination data using fourth data and first-third integrity determination data and transmit cash including fourth data and fourth integrity determination data, and third data may include index information in a table previously stored in the image forming apparatus, and fourth data may include a value corresponding to index information.

[0025] Each of the main controller and the CRUM module, when the signal including the integrity determination data is received from another element, can separate the integrity determination data from the received signal and compare the separated integrity determination data with the integrity determination data, which are generated independently of the remaining data to verify the integrity of the signal.

[0026] An image forming apparatus according to an exemplary embodiment includes an interface unit that connects to a CRUM module installed in a consumable unit integrated in the image forming apparatus, and a controller that, when an event occurs that requires authentication, authenticates CRUM the module by performing many authentication processes of the CRUM module, and the controller transmits / receives a signal including the integrity determination data in the authentication process for ormirovaniya session key and the authentication process to verify the compatibility of the plurality of authentication processes, and determine the integrity data generated by reflection accumulating manner, at least one integrity data determination included in the previously received signal.

[0027] The CRUM module installed in the consumable unit of the image forming apparatus according to an exemplary embodiment includes an interface unit that receives a signal including first data and first integrity determination data associated with the first data from the main body of the forming apparatus image, a testing unit that separates the first integrity determination data from the received signal to verify the integrity of the signal, a formation unit that generates second data integrity determinations using the second authentication data in the main body of the image forming apparatus and the first integrity determination data, and a controller that authenticates by transmitting a signal including the second data and second integrity determination data to the main body of the image forming apparatus through the interface block.

[0028] Each of the first data and the second data may include data associated with the session key to generate the session key, and the controller can generate the session key using the first data and second data and perform many subsequent authentication processes.

[0029] A plurality of subsequent authentication processes may comprise a second authentication process for synchronizing a first table stored in each of a main body of an image forming apparatus and a CRUM module, a third authentication process for synchronizing a second table stored in each of a main body of an image forming apparatus and a CRUM module, and the fourth authentication process for determining compatibility between the imaging device and the CRUM module based on at least one of first and second tables.

[0030] The controller may generate and transmit final integrity determination data by reflecting all integrity determination data that is transmitted and received in the fourth authentication process.

[0031] A method for authenticating an image forming apparatus according to an exemplary embodiment includes determining whether or not an event occurs that requires authentication of a consumable unit installed in the image forming apparatus, and after the event occurs, performing authentication of the CRUM module installed in the consumable block, through the main controller of the imaging device, for authentication of the CRUM module, and authentication is performed through many out processes ntifikatsii, and determining the integrity of the data generated by the reflection of the previous determination of the integrity of the data used by at least two authentication processes of a plurality of authentication processes.

[0032] Integrity determination data that is transmitted / received in the final authentication process from a plurality of authentication processes can be generated by cumulative reflection of all integrity determination data that is transmitted or received in previous authentication processes.

[0033] Authentication may comprise a first authentication operation in which the main controller transmits a signal including first data and first integrity determination data to a CRUM module, and the CRUM module generates second integrity determination data using the second data and first determination data integrity and transmits a signal including second data and second integrity determination data to the main controller, and a second authentication operation in which the main controller generates third data to determine integrity using third data, first integrity determination data and second integrity determination data, and transmits a signal including third data and third integrity determination data to a CRUM module, and the CRUM module generates fourth integrity determination data using fourth data and the first or third integrity determination data and transmits a signal including fourth data and fourth integrity determination data to the main controller, wherein each of the first data and second the data include data associated with the session key to form the session key, wherein the third data includes index information in a table previously stored in the image forming apparatus, and the fourth data includes a value corresponding to the index information

[0034] A method for authenticating a CRUM module installed in a consumable unit of an image forming apparatus according to an exemplary embodiment includes receiving a signal including first data and first integrity determination data for authentication from the main body of the image forming apparatus, integrity testing signal by separating the first integrity determination data from the received signal, the formation of the second integrity determination data using the second yes the first and first integrity determination data for authentication in the main body of the image forming apparatus and performing authentication by transmitting a signal including second data and second integrity determination data to the main body of the image forming apparatus.

[0035] The method may include performing a plurality of subsequent authentication processes after transmitting a signal including second data and second integrity determination data to the main body of the image forming apparatus, and integrity determination data that are transmitted / received in the final authentication process from the plurality subsequent authentication processes can be formed by reflecting in an accumulative manner all integrity determination data that is transmitted or received These are in previous authentication processes.

[0036] The final authentication process may include receiving third data, first integrity determination data and a signal including third integrity determination data generated using second integrity determination data and third data from the main body of the image forming apparatus, and generating fourth data and fourth integrity determination data using first or third integrity determination data and transmitting a signal including fourth data and four outputted integrity determination data to the main body of the image forming apparatus, and each of the first data and second data may include data associated with a session key to generate a session key, and third data may include index information in a table previously stored in the image forming apparatus, and the fourth data may include a value corresponding to index information.

[0037] An image forming apparatus according to an exemplary embodiment includes a main body that includes a main controller capable of controlling the operations of the image forming apparatus, and a consumable unit in which a module for monitoring user replaceable blocks (CRUM) is installed, and a main controller when an event occurs that requires authentication of the CRUM module, transmits a first signal including first data and first integrity determination data to the CRUM module, and CRUM the module generates the second integrity determination data using the second data and the first integrity determination data and transmits the second data and the second signal including the second data and the second integrity determination data to the main controller to perform the authentication process in order to generate the session key and the main controller transmits a third signal including third integrity determination data and third data that are generated using the first integrity determination data and the second integrity determination data, to the CRUM module, generates fourth integrity determination data using the first-third integrity determination data and transmits a fourth signal including fourth data and fourth integrity determination data to the main controller to perform an authentication process for in order to determine compatibility.

[0038] The first data may include a first command, first authentication data and a first assignment unit for assigning the first integrity determination data, and second data may include second authentication data and a second assignment unit for assigning the second integrity determination data based on the execution result operations according to the first command, the third data may include a second command, third authentication data and a third destination unit for assigning third integrity determination data, and The Fourth data may include a fourth data and a fourth authentication unit for assigning destination fourth data integrity determination based on a result of the operation according to the second team.

[0039] As mentioned above, according to various exemplary embodiments of the present disclosure, it is possible to achieve security of the entire communication by using in an accumulative manner integrity data used in the previous communication. Accordingly, information of consumable units and imaging devices can be controlled safely.

Brief Description of the Drawings

[0040] The above and / or other aspects of the present disclosure should be more apparent by describing a specific present disclosure with reference to the accompanying drawings, in which:

FIG. 1 illustrates an image forming apparatus according to an exemplary embodiment;

FIG. 2 is a timing chart illustrating a communication process between a controller and a CRUM module in an image forming apparatus according to an exemplary embodiment;

FIG. 3 is a timing chart illustrating a signal integrity analysis process using integrity determination data;

FIG. 4 is a timing chart illustrating a communication process between a controller and a CRUM module in an image forming apparatus according to an exemplary embodiment;

FIG. 5 is a block diagram illustrating an exemplary image forming apparatus installed in a consumable unit;

FIG. 6 and 7 represent an exemplary image forming apparatus according to various exemplary embodiments;

FIG. 8 illustrates a configuration of a CRUM module according to an exemplary embodiment of the present disclosure;

FIG. 9 and 10 illustrate a communication method according to various exemplary embodiments;

FIG. 11-18 are views illustrating an authentication method of an image forming apparatus according to an exemplary embodiment;

FIG. 19 is a block diagram illustrating a configuration of a CRUM module according to an exemplary embodiment;

FIG. 20 is a timing chart illustrating an authentication process;

FIG. 21-24 illustrate an example method for generating integrity determination data used for each authentication process;

FIG. 25-27 illustrate an example connection of a consumable unit to a main body of an image forming apparatus;

FIG. 28 illustrates an example waveform that is transmitted and received according to an I2C interface method; and

FIG. 29 is an enlarged view of an exemplary portion of the signal in FIG. 28.

DETAILED DESCRIPTION OF THE INVENTION

[0041] The following is a detailed reference to embodiments, examples of which are illustrated in the accompanying drawings, in which like reference numerals refer to like elements throughout. Embodiments are described below in order to explain the present invention with reference to the drawings.

[0042] Exemplary embodiments are explained in detail below with reference to the accompanying drawings.

[0043] In the description below, like reference numerals in the drawings are used for like elements. Aspects indicated in the description, such as a detailed design and elements, are provided in order to assist in a comprehensive understanding of exemplary embodiments.

[0044] FIG. 1 illustrates a configuration of an image forming apparatus according to an exemplary embodiment. As illustrated in FIG. 1, for example, an image forming apparatus includes a housing 100, a controller 110 provided in the housing 100, and a consumable unit 200 that can be installed in the housing 100. The image forming apparatus can be implemented as various types of devices, such as a printer, a scanner , multifunction device, facsimile or copy machine, which can form images on paper or on various other recording media. According to an exemplary embodiment, the housing 100 may be the main body of the image forming apparatus, and the controller 110 may be the main controller.

[0045] The controller 110 may be installed in the housing 100 of the image forming apparatus in order to control the functions of the image forming apparatus. According to an exemplary embodiment, the controller 110 is the main controller that controls all the functions of the image forming apparatus.

[0046] The consumable unit 200 may be installed in the housing 100 of the image forming apparatus and may be one of various types of blocks that are included in the image forming apparatus directly or indirectly. For example, in the case of a laser imaging device, electrical units, optical exposure units, developing units, transfer units, stabilizing units, various types of rollers, belts and drum units may be consumable units. In addition, various types of blocks that must be replaced when using the image forming apparatus can be defined as a consumable block 200.

[0047] Each consumable unit 200 may have a predetermined period of use. Therefore, the consumable unit 200 may include a microprocessor and / or circuit, such as a CRUM module 210 (module for monitoring user-replaceable blocks), which provides for replacement at the right time.

[0048] The CRUM module 210 may be installed in the consumable unit 200 and record various information. CRUM module 210 includes a storage device. Therefore, the CRUM module 210 may be referred to under various terms, for example, a memory device or a CRUM memory (monitoring memory of user replaceable blocks), but for convenience of explanation, the term “CRUM module” is used.

[0049] In the storage device provided in the CRUM module, various characteristic information can be stored with respect to the consumable unit 200, the CRUM module or the imaging device itself, as well as usage or program information associated with the imaging task.

[0050] Various programs stored in the CRUM module may include not only common applications, but also O / S (operating system) and encryption programs. Information regarding the manufacturer of the consumable unit 200, information regarding the manufacturer of the image forming apparatus, names of installed image forming apparatuses, information regarding the manufacturing date, serial number, model name, electronic signature information, encryption key and encryption key index may be included in the characteristic information. The usage information may include information such as how many sheets of paper have been printed so far, how many sheets of paper can be printed from that moment, and how much toner is left. Instead, characteristic information may also be referred to as unique information.

[0051] According to an exemplary embodiment, information, as illustrated in Table 1 below, can be stored in CRUM module 210.

Table 1 general information OS version CLP300_V1.30.12.35 02.22.2007 SPL-C Version 5.24 06-28-2006 Engine version 6.01.00 (55) USB serial number BH45BAIP914466B Installed Model Dom Service Start Date 2007-09-29 Extra options RAM size 32 megabytes EEPROM Size
USB connection (high speed) 4096 bytes Consumable Resource Total number of pages 774/93 pages (color / monochrome) Resource fuser device 1,636 pages Transfer Roller Resource 864 pages Tray Roller Resource 867 pages Total number of images 3251 images Resource imaging unit / developing roller 61 images / 19 pages Belt Resource 3251 images Number of Toner Images 14/9/14/19 images (C / M / Y / K) Toner Information The amount of remaining toner, percent 99% / 91% / 92% / 100% (C / M / Y / K) Average ink intensity 5% / 53% / 31% / 3% (C / M / Y / K) Supplies Information Cyan toner SAMSUNG (DOM) Magenta toner SAMSUNG (DOM) Yellow toner SAMSUNG (DOM) Black toner SAMSUNG (DOM) Imaging unit SAMSUNG (DOM) Color management menu Custom color Manual adjustment (CMYK: 0, 0, 0, 0) Settings menu Power saving mode 20 minutes Auto Continue Printing Included Tilt adjustment Flat

[0052] In the memory of the CRUM module 210, approximate information of the consumable unit 200 and information regarding the resource, information menu and settings of the consumable unit 200 can be stored. In addition to the body of the image forming apparatus, the O / S provided for use in the consumable unit can be stored in the storage device.

[0053] The CRUM module may include a CPU (not illustrated) that can control the storage device, execute various programs stored in the storage device, and communicate with the body of the image forming device or the controller of other devices.

[0054] The CPU may drive the O / S stored in the memory of the CRUM module and initialize the consumable unit 200 itself, in addition to initializing the image forming apparatus. The CPU can authenticate between the body of the imaging device when initialization is completed, or during initialization. When initialization is complete, it can exchange encryption data with the body of the imaging device. Various commands and data transmitted from the body of the image forming apparatus can be encrypted according to an arbitrary encryption algorithm and transmitted.

[0055] In a specific case, for example, when the power of the image forming apparatus having the consumable unit 200 is turned on, or when the consumable unit 200 is disconnected and then reconnected to the housing 100 of the image forming apparatus, the CPU can initialize itself, in addition to initializing the controller 100 Initialization includes various processes, such as the initial activation of various applications used in the consumable unit 200, the calculation of secret information necessary for the exchange of data with the controller rum 110 after initialization, setting a communication channel, initialization of memory values, checking of when to replace itself, setting of internal register values consumable unit 200, and setting of internal-external clock.

[0056] The setting of the register value may be defined as the operation of setting the functional values of the register in the consumable unit 200 so that the consumable unit 200 may operate according to various functional states that the user has previously determined. Setting the internal-external clock means the operation of adjusting the frequency of the external clock provided from the controller 110 of the imaging device, so that it corresponds to the internal clock that the CPU uses in the consumable unit 200.

[0057] Verifying when to replace yourself may be an operation of identifying the remaining toner or ink volume currently used, predicting when the ink or toner is completely consumed, and notifying the controller 110. After determining during the initialization process that the toner volume is already full consumed, the consumable unit 200 can be implemented with the ability to notify the controller 110 that it is inoperative. Since the consumable unit 200 itself has O / S, various types of initialization can be performed according to the types and characteristics of the consumable unit 200.

[0058] With the CPU installed and the O / S provided, the remaining volume of the consumable block stored in the memory 210 or the number of replenishes before the controller 110 requests communication with the block 200 can be identified when the imaging device is turned on. Accordingly, the notification time for the need to replace the consumable unit can be set earlier than before. For example, when the toner comes to an end, the user can turn on the power and then make adjustments to enter the toner save mode, and then perform imaging. In addition, the same applies when only a particular toner comes to an end.

[0059] The CPU may not respond to a command from the controller 110 until initialization is completed and then completed. The controller 110 waits for a response while transmitting the command periodically until a response is provided.

[0060] Accordingly, when the response is received, ie acknowledgment, authentication may be performed between the controller 110 and the CPU. In this case, due to the O / S itself installed in the CRUM module 210, authentication can be performed through the interaction between the CRUM block 210 and the controller 110.

[0061] The controller 110 encrypts the data or command for authentication and transmits it to the CRUM module 210. An arbitrary value of R1 may be included in the transmitted data. As used herein, R1 may be a random value that changes with each authentication, or a predefined fixed value. The CRUM module that receives the data generates a partial key using an arbitrary value of R2 and received R1 and then generates a MAC (message authentication code) using the generated partial key.

[0062] A signal including the generated MAC and R2, as mentioned above, is transmitted to the controller 110. The controller 110 generates a partial key using the received R2 and R1, generates a MAC using the generated partial key, and then certifies the CRUM module 210 by comparison the generated MAC and MAC in the received signal. According to various exemplary embodiments, electronic signature information or key information may be transmitted in such an authentication process and used in authentication.

[0063] When the authentication is successful, the controller 110 and the CRUM module exchange encryption data to manage the data. In other words, when a user command is entered, or when an imaging task is initiated or completed, the controller 110 encrypts the command or data to read, write data or additional functions using the encryption algorithm and then transfers them to the CRUM module 210.

[0064] The CRUM module 210 may decode the received command or data and perform operations such as reading or writing data according to the decoded command. The encryption algorithm used in the CRUM module 210 or controller 110 may be a standardized encryption algorithm. Such an encryption algorithm is mutable when the encryption key is disclosed, or when there is a need for increased security. Various encryption algorithms can be used, such as an algorithm with an asymmetric RSA key, an algorithm with a symmetric key ARIA, TDES, SEED, AES.

[0065] In this regard, between the CRUM module 210 and the controller 110, communication for authentication and data exchange can be performed multiple times. With each communication, signals are transmitted from the controller 110 to the CRUM module 210, or vice versa. In this case, the transmitted signal includes error detection data for determining the integrity of the data included in the corresponding signal. Such error detection data is data generated by accumulating error detection data included in a transmitted or received signal from a previous communication.

[0066] In other words, between the controller 110 and the CRUM module 210, a plurality of data exchanges can be performed, for example, authentication 1, authentication 2, authentication 3, ..., authentication n, data exchange 1, data exchange 2 ,. .., exchange of m data. According to an exemplary embodiment, integrity determination data may be included in a signal transmitted at each communication or in some communication process. In such integrity determination data, the integrity determination data used in the previous communication is reflected cumulatively.

[0067] The party that receives the signal determines the integrity of the corresponding signal using the integrity determination data in the signal. Accordingly, when the corresponding data is determined to be integral, the next operation or subsequent communication is performed. If it is necessary to record received data, data and integrity determination data included in this signal can be temporarily stored. New integrity determination data may be generated using subsequent data that must be transmitted to the party that transmitted the signal and integrity determination data received from a previous communication and temporarily stored. Accordingly, a signal to which new integrity determination data has been added may be transmitted in subsequent data. Between the controller 110 and the CRUM module 210, a connection can be made multiple times that includes such integrity determination data. When communication including the latest integrity determination data is made, a final determination can be made using the integrity determination data included in the last received signal. If everything is correct in the final determination, all data that has been temporarily stored so far can be recorded.

[0068] FIG. 2 illustrates an example communication process between a controller 110 and a CRUM module 210 according to an example embodiment of the present disclosure. According to FIG. 2, the controller 110 transmits a first signal 10, which includes data 1 and integrity determination data 1. The CRUM module 210, which receives the first signal 10, generates integrity determination data 2 using the integrity determination data 1 included in the first signal 10 and data 2. The CRUM module 210 transmits a second signal that includes data 2 and data 2 ensure integrity, to the controller 110. In this regard, signals (30, ..., N), which include integrity determination data generated using the integrity determination data from the previous connection, are performed repeatedly.

[0069] The result value of the logical calculation for the data to be transmitted, the result value generated by applying a predetermined mathematical formula to the data, or the result value of the data encryption, i.e. MAC can be used as integrity determination data.

[0070] FIG. 3 illustrates a determination method using integrity determination data. According to FIG. 3, when a signal is received that includes the data a and the integrity determination data a (S310), the CRUM module 210 separates the integrity determination data a (S320).

[0071] The CRUM module 210 generates integrity data a ’using the remaining data and integrity determination data that it transmitted during the previous communication (S330). The CRUM module 210 then compares the integrity determination data a ’correspondingly generated with the separated integrity determination data a (S340), and if they are identical, determines it as integral (S350). If they are not identical, the CRUM module 210 determines that the data is in an error state and stops communication (S360). For convenience of explanation later in this document, data a ’integrity determination is referred to as data to be compared.

[0072] When it is determined that the corresponding data is integral, the integrity determination data b is generated by using the data b to be transmitted and the determination data a (S370). Accordingly, a signal that includes data b and integrity determination data b is transmitted to the controller 110 (S380).

[0073] FIG. 3 illustrates an example determination process performed, for example, in CRUM module 210, but an identical process can also be performed in controller 110. In other words, when controller 110 receives a signal that includes data b and integrity determination data b, it separates data b determine the integrity and performs the determination. This determination method is similar to (S330) to (S370), and therefore, a second explanation and illustration are omitted.

[0074] The configuration of the signals transmitted and received between the controller 110 and the CRUM module 210 may be designed for various types. In other words, the data included in the signals may include at least one of a command, information to be recorded, resultant operation information according to a command, resultant integrity determination information regarding previously received signals and indicator information for notification the location of the integrity determination data. The resulting integrity determination information may be excluded from the signals initially transmitted and received between the controller 110 and the CRUM module 210. The method for determining the integrity data can be used for each communication operation in the above communication process, but can also be applied only to certain or important communications operations throughout the entire communications process.

[0075] FIG. 4 illustrates an exemplary embodiment of an integrity determination process using signals having other formats, for example, other than the formats of FIG. 2. Referring to FIG. 4, the controller 110 transmits a signal that includes data and integrity determination data 1 (S410). As used herein, data includes read command data (CMD) 1 and indicator U1. The read command data (CMD) 1 includes not only a command, but also a read target or a cell address of a storage device. U1 means indicator information that is provided after data 1 of a read command (CMD). The indicator information U1 means a symbol for notifying the location of the parsing of the integrity determination data in a signal. Indicator information can be expressed as a fixed number of bytes. For example, five bytes can be used for indicator information. On the other hand, the read command data (CMD) 1 is variable according to the data content, and thus the size of the integrity determination data 1 is also variable.

[0076] When a signal is received, the CRUM module 210 performs integrity determination using the integrity determination data 1 included in the signal (S415). CRUM module 210 allows the formation of integrity determination data 2 using data to be transmitted and integrity determination data 1 and transmits a signal that includes them (S420). As illustrated in FIG. 4, the read data 1 is included in the signal to be transmitted, which is data read from the memory provided in the consumable unit 100 according to the read command data (CMD) 1, the resulting data 2, which indicate the result of the operation performed according to read command data (CMD) 1, U2 indicator, and integrity determination data 2.

[0077] The controller 110 separates the integrity determination data 2 from the received signal and performs integrity determination (S425). Then, if there is subsequent read command data (CMD) 3, controller 110 generates integrity determination data 3 using read command data (CMD) 3 and integrity determination data 2 and then transmits a signal that includes read command data 3 (CMD) , indicator U3 and integrity determination data 3, in CRUM module 210 (S430).

[0078] As illustrated in FIG. 4, for example, communication is performed using a plurality of integrity determination data 4, 5, 6, T1 and T2 (S440, S450, S460, S470, S485), after which the integrity determination is performed, respectively (S435, W445, S455, S465). When the final communication signal is received from the CRUM module 210 (S470), the CRUM module 210 determines the integrity of the data that is transmitted and received in the entire communication process and temporarily stored using the integrity determination data T1 included in the final communication signal (S475). If, as a result of the final determination, it is determined that the data is integral, data that is temporarily stored is stored in a non-volatile storage device (not illustrated) (S480). Similarly, when the final communication signal is transmitted from the CRUM module 210, the controller 110 also performs a general integrity determination using the integrity determination data T2 included in the final communication signal (S490). Accordingly, data that is temporarily stored is stored in the non-volatile memory if it is determined that the data is integral (S495).

[0079] The integrity determination data used in these communication processes is generated by accumulating the integrity determination data used in the previous communication.

[0080] According to an exemplary embodiment, the integrity determination data may be processed as follows:

Integrity determination data 1 = E (CMD read data 1 | U1)

Integrity determination data 2 = E (CMD read data 2 | resulting data 2 | U2 | integrity determination data 1)

Integrity determination data 3 = E (read CMD data 3 | U3 | integrity determination data 2)

Integrity determination data 4 = E (CMD read data 4 | resulting data 4 | U4 | integrity determination data 3)

Integrity determination data 5 = E (CMD record data 5 | U5 | integrity determination data 4)

Integrity determination data 6 = E (read data 6 | U6 | integrity determination data 5)

Integrity determination data T1 = E (L1 CMD record data | U-T1 | integrity determination data T1-1)

Integrity determination data T2 = E (resulting data L2 | U-T2 | integrity determination data T1)

[0081] In the above formulas, the term "E ()" indicates the function of applying the predefined formula in order to obtain the resulting value. In this regard, the integrity determination data can be formed from summing up the previous integrity determination data and all the data to be transmitted, applying various logical calculations, such as XOR (excluding OR), from the resulting value when substituting data into other known formulas between the controller 110 and the CRUM module 210, and from the resulting value during encryption by applying the various various different encryption algorithms above.

[0082] FIG. 5 illustrates an example imaging apparatus in which a plurality of consumable units 200-1, 200-2, ..., 200-n are provided in a housing 500, according to an exemplary embodiment of the present disclosure.

[0083] As illustrated in FIG. 5, the image forming apparatus includes a controller 510, a user interface unit 120, an interface unit 130, a storage device 140, and a plurality of consumable units 200-1, 200-2, ..., 200-n.

[0084] The user interface unit 120 is used to receive various commands from the user or to display and notify various information. The user interface unit 120 may include an LCD or LED display of at least one button or speaker. It may also include a touch screen, as appropriate.

[0085] The interface unit 130 means a configuration that allows you to connect using a wired connection and / or wirelessly with a host PC or various external devices in order to communicate. The interface unit 130 may include various types of interfaces, such as a local interface, a USB (universal serial bus) interface, and a wireless network interface.

[0086] The storage device 140 is used to store various programs or data necessary for operating the image forming apparatus.

[0087] The controller 510 serves to control all operations of the image forming apparatus. The controller 510 processes the data received through the interface unit 130, and converts the processed data into a format in which an image can be formed.

[0088] The controller 510 performs an imaging task for the converted data using a plurality of consumable blocks 200-1, 200-2, ..., 200-n. The consumable unit may be provided in various ways depending on the type of imaging device.

[0089] In the case of a laser printer, electrical units, optical exposure units, developing units, transfer units, stabilizing units, various types of rollers, belts and drum units may be consumable units.

[0090] In each consumable unit 200-1, 200-2, ..., 200-n, can be included from the first CRUM module to the nth CRUM module 210-1, 210-2, ..., 210-n.

[0091] Each CRUM module may include a storage device and a CPU, etc. At least one of a crypto module, tamper detector, an interface unit, a clock signal block (not illustrated) that outputs clock signals, or a random value generation block (not illustrated) that can generate a random value for authentication may be included.

[0092] The cryptoblock (not illustrated) supports an encryption algorithm so that the CPU (not illustrated) can authenticate or encrypted communication with the controller 510. The cryptoblock can support a specific algorithm from a variety of encryption algorithms, for example, an algorithm with an asymmetric RSA, ECC, and symmetric key algorithm ARIA, TDES, SEED and AES. The controller 510 may also support the corresponding algorithm from a variety of encryption algorithms. Accordingly, the controller 510 can identify which encryption algorithm is used in the consumable unit 200, continue to execute the encryption algorithm, and perform communication during encryption.

[0093] Therefore, even when the key is issued, regardless of the type of encryption algorithm applied to the consumable unit 200, the key can be easily installed in the housing 100, and communication is performed during encryption.

[0094] An unauthorized tamper detector (not illustrated) is a unit for protecting against various physical cracking attempts, i.e. unauthorized interference. The tamper detector monitors the working environment, such as voltage, temperature, pressure, light and frequency, and when an attempt occurs, for example, to remove the protective cap, it erases or physically blocks the data. In this case, the tamper detector may have a separate power supply.

[0095] The storage device provided in the CRUM module 210 may include an O / S storage device, a non-volatile storage device, or a non-volatile storage device. An O / S memory device (not illustrated) may store O / S for driving the consumable unit 200. Non-volatile memory device (not illustrated) may store various non-volatile data. Various information can be stored in the non-volatile memory, for example, electronic signature information, various information of the encryption algorithm, information regarding the status of the consumable unit 200 (for example, the remaining toner volume, when to replace the toner, the remaining number of sheets for printing, etc.) , unique information (e.g. manufacturer information, manufacturing date information, serial number, product model name, etc.) and A / S information. Data received during communication with the controller can be stored in non-volatile memory.

[0096] Volatile memory (not illustrated) can be used as temporary storage space necessary for operation. In volatile memory, data determined to be integral in each connection and integrity determination data used in each determination can be temporarily stored.

[0097] An interface unit (not illustrated) serves to connect the CPU to the controller and can be implemented as a serial interface or a wireless interface. Since the serial interface uses fewer signals than the parallel interface, it has the effect of reducing costs and is additionally preferred in a work environment in which there is a lot of noise, for example, in a printer.

[0098] A CRUM module may be provided in each consumable unit. Each CRUM module can communicate with the controller and other CRUM modules. During the communication, new integrity determination data is transmitted, generated by accumulating the integrity determination data used in the previous communication.

[0099] FIG. 6 illustrates an image forming apparatus according to an exemplary embodiment of the present invention. As illustrated in FIG. 6, for example, the image forming apparatus includes a controller 610 and an interface unit 630, and the controller 610 includes a data processor 111, a forming unit 112, a determining unit 113, and a control unit 114.

[00100] The data processor 111 generates data to be transmitted to the CRUM module installed in the consumable unit, which can be installed in the image forming apparatus. The data includes at least one of a command and information to be processed by this command. In other words, in the case of a read command, the address of the storage device to be read, or information regarding the object to be read, can be transmitted together. In the case of a recording command, information to be recorded may be transmitted together. The data processor 111 may output the data as is, or may encrypt the data and then output it. Various commands, for example, an authentication command and information associated with these commands, may be generated in the data processor 111. These commands and information can often be generated before, during or after the imaging task. For example, when the image forming apparatus is turned on, or when the consumable unit 200 is disconnected and then reconnected, or when an initialization command for specifying the image formation is entered, the controller 110 may transmit an authentication command or a read command for authentication in the consumable unit 200. Accordingly, the controller 610 can identify various information managed in the consumable unit 200 itself, or store it in a storage device 140 of the housing of the image forming apparatus 100 nings.

[00101] During or after completion of the imaging task, the data processor 111 may generate a recording command and related information to record information regarding the consumable item, i.e. information regarding ink or toner, the number of printed pages, the number of printed dots, and background information regarding the user who is printing to the consumable unit 200.

[00102] The forming unit 112 generates integrity determination data using data output from the data processor 111. The generating unit 112 can simply summarize the data output from the data processor 111, perform a logical calculation such as XOR, perform a substitution in a predefined mathematical formula, or encrypt the data using an encryption algorithm and output the resulting value as the integrity determination data. If there are integrity determination data used in the previous communication, the forming unit 112 collectively accumulates and reflects even these previous integrity determination data and generates integrity determination data.

[00103] The integrity determination data generated in the generating unit 112 is added to the data generated in the data processor 111 and transmitted to the interface unit 630. In FIG. 6, it is illustrated that only the output of the data processor 111 is provided to the generating unit 112, but the output of the data processor 111 can be provided directly to the interface unit 630 or provided to the multiplexer (not illustrated). In the event that a multiplexer is provided, the output of the generating unit 112 is also provided to the multiplexer and may be transmitted to the interface unit 630 in the form of a signal in which data and integrity determination data are included together.

[00104] The interface unit 630 transmits a signal, which includes data and first integrity determination data, to the CRUM module 210.

[00105] The interface unit 630 may receive a response signal from the CRUM module 210. For convenience of explanation, the signal transmitted from the interface unit is referred to as the first signal, and the signal transmitted from the CRUM module is referred to as the second signal.

[00106] The second integrity determination data included in the second signal is data in which the first integrity determination data is accumulated and reflected.

[00107] The determination unit 113 separates the second integrity determination data included in the second signal received through the interface unit 630, and determines the integrity of the data included in the second signal. More specifically, the determination unit 113 applies the known method between the CRUM module 210 with respect to the remaining data after separating the second integrity determination data and the integrity determination data that the controller 610 previously transmitted, and generates integrity determination data.

[00108] The determination unit 113 compares the integrity determination data appropriately generated with the second integrity determination data separated from the second signal, and determines whether they are identical or not. If they are identical, the determination unit 113 determines that the corresponding data is integral, and if they are not identical, the determination unit 113 determines that the corresponding data is in an error state.

[00109] The control unit 114 carries out subsequent communication according to the determination result by the determination unit 114. In other words, if it is determined that the second signal includes data in an error state, the control unit 114 may terminate the subsequent communication or make another attempt. If it is determined that the second signal is in the normal state, i.e. in integral state, the control unit 114 carries out subsequent communication.

[00110] According to an exemplary embodiment, after determining that the corresponding data is in an integral state, the control unit 114 may store the corresponding data directly into the memory 140.

[00111] According to an exemplary embodiment, the control unit 114 may temporarily store data obtained with each communication and integrity determination data, and when the final communication is completed, record temporarily stored data in the memory 140.

[00112] FIG. 7 illustrates an image forming apparatus according to an exemplary embodiment. As illustrated in FIG. 7, the housing 700 includes a storage device 740 in addition to a controller 710, which includes a data processor 711, a generating unit 712 and a determining unit 713, and a control unit 714 and an interface unit 730. The storage device 740 includes a temporary storage unit 741 and block 742 storage.

[00113] Accordingly, in the temporary storage unit 741, data defined as integral and integrity determination data can be temporarily stored. The temporarily stored integrity determination data may be used during the integrity determination in a subsequent communication process.

[00114] In other words, when the second signal associated with the first signal is transmitted after the first signal, which includes the first integrity determination data, is transmitted to the CRUM module 210, the determination unit 713 separates the second integrity determination data from the second signal and generates new integrity determination data, i.e. data to be compared using the remaining data and integrity determination data stored in the temporary storage unit 741. Thereafter, the determination unit 713 compares the newly generated integrity determination data with the second integrity determination data in the temporary storage unit 741 and can determine the integrity of the second signal or data included in the second signal.

[00115] The generating unit 712 may generate, for example, third integrity determination data based on subsequent data and second integrity determination data, if there is subsequent data to be transmitted to CRUM module 210 in a state in which the second signal is integral. Accordingly, the interface unit 730 transmits the third integrity determination data and the third signal, which includes subsequent data, to the CRUM module 210. In other words, as illustrated in FIG. 2-4, the controller and the CRUM module communicate multiple times.

[00116] The determination unit 713 may perform a final determination for the integrity of all signals received during communication using the final integrity determination data included in the signal received during the communication. In other words, as mentioned above, the integrity determination data transmitted and received during communication is generated by accumulating and analyzing the previous integrity determination data, and thus the final integrity determination data includes all data from the very first integrity determination data right up to the data directly before the current data. Therefore, if it is determined that the data is integral using the final integrity determination data, all temporarily stored data is stored in the storage unit 742 in the memory 740 when communication requiring recording is made based on the determination that all communication content is reliable .

[00117] During the first communication, the controller 710 and the CRUM module 210 include an indicator that notifies that it is the first communication, and then transmit a signal, and during the final communication, include an indicator that notifies that it represents the final connection, and then transmit the signal. Accordingly, when this determination is made from a signal received from another element, the controller 710 and the CRUM module 210 perform the above final determination and store the data in the storage unit 742.

[00118] Such a final determination can be made when one imaging task is completed, or in each unit of a time period previously determined according to exemplary embodiments. It can also be performed when a user command for storing data is entered, when a shutdown command associated with the image forming apparatus is entered, or during authentication of the image forming apparatus and the consumable unit.

[00119] FIG. 6 and 7 illustrate that an example data processor, a generating unit, a determining unit, and a control unit are included in the controller, but this is not necessarily limited to such an embodiment. In other words, at least one of a data processor, a generating unit, a determining unit, and a control unit may be provided, in addition to the controller. In this case, in contrast to that illustrated in FIG. 1-4, the controller can only perform the initial function, and communication with the CRUM module 210 can be performed by a data processor, a generating unit, a determining unit, and a control unit.

[00120] FIG. 8 illustrates the configuration of a CRUM module 810 according to an exemplary embodiment of the present disclosure. As illustrated in FIG. 8, the CRUM module 810 includes an interface unit 811, a determination unit 812, a generating unit 2813, a data processor 814, a control unit 815, a temporary storage unit 816, and a storage unit 817.

[00121] The interface unit 811 receives a first signal, which includes first data and first integrity determination data, from a housing of an image forming apparatus, in particular a controller mounted in a housing.

[00122] The determination unit 812 separates the first integrity determination data from the first signal and determines the integrity of the first signal. The determination method of the determination unit 812 is similar to the method illustrated above, and therefore, a second explanation is omitted.

[00123] The temporary storage unit 816 temporarily stores the first data and the first integrity determination data when it is determined that the first signal is integral.

[00124] The data processor 814 generates second data when there is second data to be transmitted to the body of the image forming apparatus.

[00125] The generating unit 813 generates second integrity determination data using the generated second data and first integrity determination data.

[00126] The control unit 815 controls the interface unit to transmit a second signal, which includes second data and second integrity determination data, to the body of the image forming apparatus. In addition, the control unit 815 controls all the operations of the CRUM module. In other words, as mentioned above, when the CRUM module itself has O / S, the control unit 815 can drive the CRUM module using O / S. When saving the initialization program, the initialization can be performed separately from the body of the image forming apparatus.

[00127] The control unit 815 performs an operation corresponding to each command received from the body of the image forming apparatus. In other words, when a read command is received, the control unit 815 reads the data stored in the storage unit 817 according to this command and transmits the data to the image forming apparatus via the interface unit 811. In this process, integrity determination data can be added.

[00128] Meanwhile, the determination unit 812 performs integrity determination for the third signal when the third signal, which includes the third integrity determination data, is generated by accumulating and analyzing the second integrity determination data.

[00129] When the communication is completed, the determination unit 812 determines all signals received during the imaging task using the final integrity determination data included in the signal received in the communication process. When the communication is completed in the integrity state, the temporary storage unit 816 stores, if necessary, data that is temporarily stored in the storage unit 817.

[00130] In other words, when the communication is completed, the control unit 815 controls the determination unit 812 to perform the final determination using the final integrity determination data. Accordingly, when as a result of the final determination in the determination block 812 it is determined that the corresponding data is integral, the control unit 815, if necessary, stores data that is temporarily stored in the temporary storage unit 816 in the storage unit 817.

[00131] The operations of the CRUM module 810 in FIG. 8 are similar to the operations of the image forming apparatus of FIG. 7. In other words, the controller of the image forming apparatus and the CRUM module of the consumable unit perform operations that likewise correspond to each other, as illustrated in FIG. 1-4. Therefore, both parties must generate integrity determination data and must have algorithms that perform the determination using the generated integrity determination data.

[00132] FIG. 9 illustrates a method according to an exemplary embodiment of the present disclosure. The communication method illustrated in FIG. 9 may be implemented in a controller provided in the housing of the image forming apparatus, or in a CRUM module provided in a consumable unit.

[00133] As illustrated in FIG. 9, when data to be transmitted is generated (S910), integrity determination data is generated using these generated data (S920).

[00134] After that, the generated integrity determination data and a signal that includes data are transmitted (S930).

[00135] Accordingly, a response signal corresponding to the transmitted signal is received from another element (S940). The response signal includes new integrity determination data generated by accumulating and analyzing integrity determination data transmitted from S930.

[00136] The integrity determination is performed using the integrity determination data included in the response signal (S950).

[00137] Thus, according to an exemplary embodiment, it is possible to determine the integrity of each communication using the previous integrity determination data in an accumulated manner.

[00138] FIG. 10 illustrates a communication method according to an exemplary embodiment. As illustrated in FIG. 10, when data to be transmitted is generated (S1010), integrity determination data is generated based on this data (S1020). After that, a signal is transmitted, which includes data and integrity determination data (S1030), and a response signal associated with this signal is received (S1040). Accordingly, the integrity determination data is separated from the response signal (S1050).

[00139] Whether the data is complete or not can be determined using the remaining data from which the integrity determination data is separated and the existing integrity determination data (S1060).

[00140] If it is determined that the data is integral, as a result of the determination, the data is temporarily stored (S1070), while if it is determined that the data is in an error state, communication is terminated (S1100), or another attempt may be made.

[00141] If there is subsequent data in a temporarily stored state (S1080), the above step may be repeatedly performed. If there is no further data, the temporarily stored data is stored according to the result of determining the integrity of the received signal (S1090).

[00142] In the above exemplary embodiments, in addition to the integrity determination data transmitted from the controller of the image forming apparatus during the first data exchange initialization, the integrity determination data is generated by accumulating and analyzing the integrity determination data during the previous communication. As a result, the integrity determination data during the final communication includes all integrity determination data used in some, for example, important communication processes. Therefore, accurate data can be recorded.

[00143] Thus, it is possible to safely protect information regarding the controller and CRUM module from external influences such as noise, poor contact point, abnormal changes in consumables, intentional modification and cracking.

[00144] According to an exemplary embodiment, it can be based on an image forming apparatus and a CRUM module mounted in a consumable unit used in an image forming apparatus, but the above communication method can also be applied to other types of devices. For example, an exemplary embodiment includes, can be applied to the case of communication between a device made for communication with a CRUM module and not to an image forming device, as well as to the case of communication between a conventional electronic device and a storage device installed in a component used in this device.

[00145] Integrity determination data may be used, for example, only for certain authentication processes. In other words, the main controller provided in the main body of the image forming apparatus can authenticate in the CRUM module of the consumable unit in various cases, for example, when the expendable unit in which the CRUM module is installed is replaced when the imaging device is booted, when updating data is required, when a predetermined period of time arrives, etc.

[00146] The CRUM module may be designed to authenticate with the image forming apparatus and perform operations such as reading or writing data from the CRUM module only when it is confirmed that the CRUM module is suitable for the corresponding image forming apparatus. There may be various types of authentication, which can be selected depending on the circumstances. For example, if the information of the previous CRUM module cannot be used due to the initial loading or replacement of the consumable unit, an authentication method can be used that has a high level of encryption but requires a relatively longer time to complete. In case authentication is required to update part of the data during printing, faster and easier authentication can be performed. Although authentication performed during the printing process is relatively simple, it is a strong authentication method in terms of encryption, as it is based on data generated during previous authentication with a high level of encryption.

[00147] FIG. 11 illustrates an example authentication process between a main body of an image forming apparatus and a CRUM module installed in a consumable unit. Referring to FIG. 11, the main body 100 of the image forming apparatus and the CRUM module 210 performs final authentication after passing through several authentication processes (Auth-1 ~ 4). The number and order of authentication processes (Auth-1 ~ 4) may vary in various exemplary embodiments. The main body 100 of the image forming apparatus and the CRUM module 210 may perform an authentication process for generating a session key and an authentication process for verifying the compatibility of the CRUM module, and one or more authentication processes may be performed before, after, or between authentication processes.

[00148] As illustrated in FIG. 11, authentication can be divided into basic authentication and additional authentication. Basic authentication includes the first authentication process (Auth-1) to perform internal authentication, and additional authentication includes several operations, for example, Auth-2, Auth-3 and Auth-4.

[00149] The first authentication process (Auth-1) performs authentication between the image forming apparatus 100 and the CRUM module 210 and performs an operation to create a common session key. The image forming apparatus 100 and the CRUM module 210 exchange data with each other by encrypting all or part of the data that is transferred between them during communication using an encryption algorithm such as a symmetric key or an asymmetric key, so that the data cannot be seen from the outside .

[00150] The image forming apparatus 100 and the CRUM module 210 create a common session key using the data transmitted during the first authentication process (Auth-1), and use the session key to encrypt the data for subsequent communication.

[00151] The second authentication process (Auth-2) means an operation to synchronize the combination table (C-table) of the image forming apparatus 100 with the combination table of the CRUM module 210. The C-table is information that is used to authenticate each other by the device 100 imaging and CRUM module 210. In other words, a C-table means a table in which a value is written that should be controlled when sending the request code, and may also be referred to as the first table.

[00152] When bootstrapping is performed on the image forming apparatus 100, or when it is determined that the C table of the image forming apparatus 100 is not consistent with the C table of the CRUM module 210, a second authentication process may be performed to synchronize C -tables of the image forming apparatus 100 and the CRUM module 210. Whether or not the C-table of the image forming apparatus 100 is consistent with the C-table of the CRUM module 210 can be determined in the image forming apparatus 100.

[00153] FIG. 12 is a timing chart that illustrates an exemplary second authentication process. As illustrated in FIG. 12, the image forming apparatus 100 may generate PRT data and REQEST_CMD (request command) (S1110) and transmit them to the CRUM module 210. REQUEST_CMD may be provided in various formats. For example, REQUEST_CMD may be CMD || E (PRT data) || MAC || CRC (cyclic redundancy check) or EDC (error detection and correction bits). "E ()" represents the cryptographic algorithm, and "||" represents a predefined operation symbol, i.e. summation symbol.

[00154] When REQUEST_CMD is received, the CRUM module 210 generates CRUM data (S1230) and generates a C-table using the generated CRUM data and received PRT data (S1240). CRUM module 210 may generate a C-table by applying a predefined configuration function with respect to CRUM data and PRT data.

[00155] The CRUM module 210 may generate a RESPONSE including the generated CRUM data (S1250) and transmit the generated RESPONSE to the image forming apparatus 100 (S1260). RESPONSE can be generated using the E methods (CRUM data) || MAC || CMD result || CRC or EDC.

[00156] The image forming apparatus 100 generates a C-table using the received CRUM data and PRT data (S1270). The image forming apparatus 100 may also generate a C-table by applying a predetermined configuration function. Therefore, the image forming apparatus 100 and the CRUM module 210 may have an identical C table, respectively.

[00157] When the second authentication process (Auth-2) is completed, a third authentication process (Auth-3) can be performed. The third authentication process (Auth-3) may be a process in which the image forming apparatus 100 and the CRUM module 210 synchronize a query table (Q table). Q-table means a table in which authentication data such as a request code is recorded, and may also be referred to as a second table.

[00158] FIG. 13 illustrates an exemplary third authentication process. As illustrated in FIG. 13, when the second authentication process is completed, the main body of the image forming apparatus 100 determines whether the version of the Q table in the main body (i.e., the PRT version) of the version of the Q table in the CRUM module 210 is higher or not (S1310). If it is determined that the PRT version is higher than the CRUM version, the main body of the image forming apparatus 100 provides information related to the Q-table to the CRUM module 210. Accordingly, the CRUM module 210 updates the CRUM version so that it matches with a Q-table version of the main body of the image forming apparatus (S1320).

[00159] On the other hand, if the PRT version is lower than the CRUM version (S1330), the CRUM module 210 provides information related to the Q-table to the main body of the image forming apparatus 100. Accordingly, the image forming apparatus 100 updates the PRT version so that it matches the Q-table version of the CRUM module 210 (S1340).

[00160] In fact, when the Q-tables of both parties become consistent through updating, or if they are consistent without updating, the operation of checking the request code is performed, that is, values recorded in the Q-table (S1350). Such an operation of verifying a request code may be a fourth authentication process.

[00161] FIG. 14 illustrates an example process for synchronizing a Q-table with a Q-table of a main body of an image forming apparatus. As illustrated in FIG. 14, the image forming apparatus 100 generates REQUEST_CMD1 to request CRUM data (S1410), and transmits REQUEST_CMD1 to the CRUM module 210 (S1415). The CRUM module 210 generates RESPONSE 1 in response to REQUEST_CMD1 (S1420) and transmits RESPONSE 1 to the image forming apparatus 100 (S1425). RESPONSE 1 can be generated using methods E1 (E2 (PRT index of Q data) || CRUM data) || MAC || result CMD1 || CRC or EDC. Herein, E1 means an encryption algorithm, and E2 (PRT index of Q data) can be defined as obtaining Q data by applying the index of the Q table to the Q table and encrypting the Q data using an arbitrary first encryption algorithm.

[00162] When RESPONSE 1 is received, the image forming apparatus 100 compares the received Q data (S1430). In other words, the image forming apparatus 100 determines the Q data corresponding to the index that is transmitted to the CRUM module 210 from the stored Q table and compares the Q data with the Q data transmitted from the CRUM module 210 to determine whether they are consistent with each other or not. If it is determined that they are not consistent, the image forming apparatus 100 generates REQUEST_CMD2 (S1435) and transmits REQUEST_CMD2 to the CRUM module 210 (S1440). REQUEST_CMD2 can be generated using the E1 methods (E5 (PRT Q-table) || MAC || CRC or EDC. In this document, E5 means a second encryption algorithm that is different from E1 and E2.

[00163] When REQUEST_CMD2 is received, the CRUM module 210 compares the Q-table version of the image forming apparatus with the Q-table version of the CRUM module 210, and if it is determined that they are not consistent (S1445), or a rule that is different from the rules for the Q-table of CRUM module 210, (S1450), an error response is generated. Accordingly, the CRUM module 210 updates its Q-table so that it matches the PRT Q-table (S1455), generates RESPONSE 2 (S1460), and transmits RESPONSE 2 to the image forming apparatus 100 (S1465). RESPONSE 2 can be generated using the CMD2 || CRC or EDC Result methods.

[00164] FIG. 15 is a timing chart illustrating an exemplary process for synchronizing a Q-table with a Q-table of a CRUM module 210. As illustrated in FIG. 15, the image forming apparatus 100 generates REQUEST_CMD (S1510) and transmits REQUEST_CMD to the CRUM module 210 (S1520). The CRUM module 210 generates a RESPONSE according to the received command (S1530) and transmits the RESPONSE to the image forming apparatus 100 (S1540). RESPONSE can be generated by using the methods E1 (E2 (CRUM Q-data) || E5 (CRUM Q-table)) || MAC || CMD result || CRC or EDC. When a RESPONSE is received, the image forming apparatus 100 checks the CRUM Q data of the received RESPONSE and compares the CRUM Q data with the response CRUM Q data (S1550). If it is determined that they are not consistent with each other, the error state is determined. The image forming apparatus 100 checks whether or not the received QUM Q-table matches the rule for the Q-table, and if it is determined that the Q-table is not valid, an error state is determined (S1560).

[00165] If it is determined that the Q-table is not consistent, the image forming apparatus 100 updates the Q-table in accordance with the received data (S1570). Therefore, Q-tables of both sides are synchronized with each other.

[00166] The second and third authentication processes (Auth-2, Auth-3) are processes for synchronizing the information of the image forming apparatus 100 and the consumable unit 200 in order to analyze the data that is transmitted during the fourth authentication process (Auth- four). If the existing data is already identical, the third authentication process (Auth-3) may not be performed.

[00167] The fourth authentication process (Auth-4) is an authentication process to confirm compatibility. In the fourth authentication process, the image forming apparatus 100 and the consumable unit 200 use a session key generated by the first authentication process (Auth-1) and information shared during the second and third authentication processes (Auth-2, 3) to confirm that whether or not the consumable unit 200 or the CRUM module 210 installed in the consumable unit 200 is suitable for the image forming apparatus 100.

[00168] FIG. 16 is a timing chart that illustrates an example method for performing a fourth authentication process (Auth-4). As illustrated in FIG. 16, the image forming apparatus 100 selects a Q index, C index, etc., generates a REQUEST_CMD including the selected indices (S1610), and transmits REQUEST_CMD to the CRUM module 210 (S1620). The CRUM module 210 generates CRUM data using the received REQUEST_CMD, generates a RESPONSE including them, and transmits the RESPONSE to the image forming apparatus 100 (S1640).

[00169] When a RESPONSE is received, the image forming apparatus 100 generates RPT Q data (S1650) and compares the PRT Q data with CRUM data included in the RESPONSE (S1660). If it is determined that they are consistent with each other, it is determined that the CRUM module 210 is proper, and authentication is completed.

[00170] The image forming apparatus 100 and the consumable unit 200 may transmit / receive a signal including integrity determination data during the first authentication process (Auth-1) to create a session key, and during the fourth authentication process (Auth-4 ) to confirm compatibility. Integrity determination data means data that is generated by reflecting in an accumulative manner integrity data included in previously received signals. If the signals including the integrity determination data are not received earlier, i.e. if the integrity determination data is to be generated for the first time, the integrity determination data can be generated using only the data to be transmitted.

[00171] The transmitted data replaced during the second and third authentication processes (Auth-2, Auth-3) affect the next communication process, which is the fourth authentication process (Auth-4). Accordingly, even if the integrity determination data is not used in the intermediate authentication process, the fourth authentication process (Auth-4) may fail when a problem occurs in the second and third authentication processes (Auth-2, Auth-3), thereby ultimately leading authentication failed. Therefore, it is not necessary to include integrity determination data in the entire authentication process, and integrity determination data can only be included in Auth-1 and Auth-4, which are important authentication processes. However, this is only an example, and integrity determination data may be transmitted / received in each authentication process or in at least one of the second and third authentication processes.

[00172] According to an exemplary embodiment, authentication can be performed between the main body 100 and the CRUM module 210, but such an authentication operation can be performed between the main controller 110 installed in the main body 100 and the CRUM module 210. An exemplary authentication process between the main controller 110 and CRUM module 210 is explained with reference to FIG. 17 and 18.

[00173] FIG. 17 illustrates an exemplary first authentication process (Auth-1) to generate a session key in a plurality of authentication processes. For convenience of explanation, the authentication process to generate the session key may be defined as the first authentication in the exemplary embodiment, but other authentication processes may be performed prior to the authentication process to generate the session key.

[00174] As illustrated in FIG. 17, the first authentication process (Auth-1) can be divided into com-1 and com-2. The com-1 process is a process for transmitting data, so that the main controller 100 can perform an authentication operation using the CRUM module 210. The signals transmitted during the com-1 process include CMD1, DATA1, CRC1, character, VC1, and t .d. CMD1 represents a command and may include selectable authentication related parameters or information regarding the size of the data to be transmitted. DATA1 includes random data necessary for authentication, data values associated with encryption for authentication, specific information stored in the image forming apparatus, etc. In the case of the first authentication process, not only the above random data (R1), but also the data associated with the session key, for example, information regarding the key size, various keys used in the asymmetric key algorithm, etc., and other information stored in the main body of the image forming apparatus 100 may be transferred to DATA1. According to an exemplary embodiment, a portion of the above information may be omitted or replaced with other information.

[00175] The random data may be a value that the main controller 110 generates arbitrarily for authentication. Accordingly, random data may vary for each authentication, but sometimes a single value can be transmitted, which is set temporarily, instead of random data. CRC1 represents an error detection code. CRC1 is sent to check for errors in CMD1 and DATA1. Other error detection methods, such as checksum or MAC, may be used in addition to or instead of CRC1.

[00176] The symbol in com-1 indicates integrity determination data. FIG. 17 illustrates a case in which SECU1 is used as a symbol that can identify integrity determination data from other data and display an operation type of integrity data. SECU1 used in FIG. 17 is a symbol representing a first relationship using the integrity determination data function. VC1 is the integrity determination data that is generated for the first time. VC1 generates content consisting of the line CMD1, DATA1, CRC1 and SECU1 according to a particular equation. Since VC1 is the integrity determination data generated for the first time, it is generated not by accumulating reflectively the integrity determination data received earlier, but using only the remaining data. A method of forming VC1 is disclosed.

[00177] When the CRUM module 210 receives com-1, the CRUM module 210 transmits com-2, which includes DATA2, SW2, CRC2, SECU2, VC2, etc. If the first authentication process means an authentication process for generating a session key, data com-2 may include first random data (R1), second random data (R2), module serial number (CSN), information regarding the key used for the algorithm with asymmetric key, part of the internal information of the CRUM module, etc. The first random data (R1) is the value received at com-1, and the second random data (R2) is the value that is generated from the CRUM module 210. The information included in com-2 may be omitted or replaced with other information.

[00178] In addition, SW2 provides result data that shows the result of a job executed in the CRUM module 210 according to the command com-1. Since CRC2 and SECU2 operate similarly to CRC1 and SECU1 in com-1, descriptions associated with CRC2 and SECU2 are omitted. VC2 is the integrity determination data that is generated by reflectively accumulating VC1, which is the com-1 integrity determination data. CRUM module 210 may generate VC2 by combining DATA2, SW2, CRC2, and SECU2, which are to be transmitted to com-2, with VC1 according to a predefined method, which is explained in more detail below.

[00179] If the first authentication process is performed, as illustrated in FIG. 17, the first random data (R1) generated by the main controller 110 and the second random data (R2) generated in the CRUM module 210 can be shared with each other. The main controller 110 and the CRUM module 210 may generate a session key using R1 and R2, respectively.

[00180] As illustrated in FIG. 11, the final authentication is performed after passing through a plurality of authentication processes. Of the processes, the fourth authentication process is to check the compatibility of the CRUM module 210 or the consumable unit 200 installed in the CRUM module 210. At least one more authentication process may be added between the first authentication and the fourth authentication to prepare for the fourth authentication.

[00181] FIG. 18 illustrates an example authentication process to confirm compatibility. In FIG. 11, an authentication process to confirm compatibility, which is the fourth authentication, is performed by the last of a plurality of authentication processes, but the order is not limited thereto.

[00182] As illustrated in FIG. 18, the fourth authentication process (Auth-4) comprises com-3 and com-4. Com-3 means the process in which the main controller 110 transmits a signal to the CRUM module 210, and com-4 means the process in which the CRUM module 210 transmits a signal to the main controller 110. CMD3, DATA3, SECT1 and VC3. CMD3 is a command representing com-3, and DATA3 represents the data necessary to perform an Auth-4 operation. The main controller 110 may pre-save the table in order to confirm the compatibility of the CRUM module 210 or the consumable unit 200. For example, if multiple tables are stored, DATA3 may include any of the first index information (index 1) of table 1 and any of the second index information ( index 2) of table 2. The main controller 110 may encrypt DATA3 using a session key generated through the first authentication process. SECT1 is a character string to report on the last communication operation using the integrity determination data, and VC3 is the integrity determination data. The main controller 110 may generate VC3 using the lines CMD3, DATA3, CRC3, SECT1 and VC1 and VC2, which are the integrity determination data that are currently generated. The CRUM module 210, which receives com-3, transmits com-4 to the main controller 110. Com-4 may include DATA4, SW4, CRC4, SECT2, VC4, etc. DATA4 may include a third value that is generated using the first value (value 1) and the second value (value 2) corresponding to the first and second index information received from com-3, respectively. The main controller 110 can confirm whether or not the CRUM module 210 or the consumable unit 200 is suitable for the image forming apparatus 100 by comparing the first, second and third values confirmed through com-4 with the table. Functions SW4, CRC4 and SECT2 are disclosed. VC4 is the integrity determination data that is generated by reflectively accumulating VC1, VC2, and VC3.

[00183] Integrity determination data may be transmitted / received during at least some of the plurality of authentication processes. In this case, if previously used integrity determination data exists, the corresponding integrity determination data may be reflected in an accumulating manner. In other words, the integrity determination data can be summarized according to equation 1:

equation 1

VCn SECU (n) = CMD (+) DATA (+) SW (+) CRC (+) character (+) VC (n-1)

VCn SECT (n) = CMD (+) DATA (+) SW (+) CRC (+) symbol (+) VC (1) (+) VC (2) (+) ... (+) VC (n- 2) (+) VC (n-1)

[00184] In equation 1, (+) can represent an equation based on a logical operation such as XOR, or other equations for an encryption algorithm. According to Equation 1, the VCN SECU (n), which is the integrity determination data used in authentication processes other than the final authentication process, can be generated by combining each of the data to be transmitted and VC (n-1), which represents the integrity determination data previously adopted. On the other hand, the VCN SECT (n), which is the integrity determination data used for the final authentication process, can be generated by combining each of the data to be transmitted and the general integrity determination data transmitted or received in previous authentication processes . For example, in the case of n-th integrity determination data, the integrity determination data 1, 2, ..., n-1 may be reflected. Accordingly, if an error exists in the authentication process, an error can be detected in the final authentication process, and the authentication can be completed, or it can be determined that the authentication failed.

[00185] FIG. 19 illustrates an exemplary configuration of a CRUM module using integrity determination data in an authentication process according to an exemplary embodiment. The CRUM module 1400 can be installed in various consumable units and then used. As illustrated in FIG. 19, the CRUM module 1400 comprises an interface unit 1410, a test unit 1420, a forming unit 1430, and a controller 1440. The interface unit 1410 is a component that can be connected to the main body 100 of the image forming apparatus. Interface unit 1410 may accommodate various interface connection methods. For example, an interface integrated circuit (I2C) may be used.

[00186] If an event occurs that requires authentication, the interface unit 1410 may receive various signals. For example, the interface unit 1410 may receive a signal including first authentication data and first integrity determination data associated with the first data from the main body 100. The first data represents data, excluding the first integrity determination data, from among the received signals. The first data of FIG. 17 represent CMD1, DATA1, CRC1, and SECU1. DATA1 may include various data, for example, the first random data.

[00187] Testing unit 1420 may test signal integrity by separating the first integrity determination data, i.e. VC1, from received signals. According to the first authentication process of FIG. 17, the test unit 1420 may calculate VC1 by processing CMD1 (+) DATA1 (+) CRC1 (+) SECU1. Testing unit 1420 may compare VC1, which is separate from com-1, with VC1, which is directly computed, and determine that com-1 is coherent if they are consistent.

[00188] If it is determined that com-1 is integral, the controller 1440 may temporarily store some necessary data, including VC1. A controller 1440 controls the generating unit 1430 to perform the first authentication process.

[00189] The forming unit 1430 generates second integrity determination data using the second authentication data in the main body of the image forming apparatus and the first integrity determination data. A generating unit 1430 may generate second random data using a random value generating algorithm. According to an exemplary embodiment using the above equation 1, the second integrity determination data may be calculated as the resultant value DATA2 (+) SW2 (+) CRC2 (+) SECU2 (+) VC1.

[00190] The controller 1440 may perform a first authentication operation using data received from the main body 100. The controller 1440 may generate a session key using the first random data (R1) received from the main body 100 and the second random data (R2) generated by block 1430 formation.

[00191] The controller 1440 transmits a signal including the calculated second integrity determination data along with the second data, i.e. DATA2, SW2, CRC2 and SECU2, to the main body 100 of the image forming apparatus via the interface unit 1410. The main body 100 of the image forming apparatus can also determine the first and second random data from the received signal and generate the session key using certain data.

[00192] Authentication includes many authentication operations. In other words, the controller 1440 may perform many subsequent authentication processes after generating the session key using the first and second data.

[00193] Many of the subsequent authentication processes may include an authentication process for compatibility testing, as described above with respect to the fourth authentication process. During this authentication process, new integrity determination data, which reflects in an accumulating manner, integrity determination data that has already been transmitted and received, can be transmitted and received.

[00194] The interface unit 1410 may receive a signal including third data and third integrity determination data from the main body 100 of the image forming apparatus. The third integrity determination data represents data that is generated using the integrity determination data that has been used by the main body 100 of the image forming apparatus and the main controller 110 to date, and third data. If the fourth authentication process is the final authentication process, all of the first and second integrity determination data may be reflected to form third integrity determination data.

[00195] If third data and third integrity data are received, the controller 1440 controls the testing unit 1420 to test the data. The testing method is as described above.

[00196] If, based on the test result, it is determined that there are no problems with the third data, the controller 1440 controls the forming unit 1430 so as to generate the fourth integrity determination data. The generating unit 1430 may generate fourth integrity determination data by reflecting the fourth data along with the first, second, and third integrity determination data in the above equation 1.

[00197] If fourth integrity determination data is generated, the controller 1440 transmits a signal including fourth data and fourth integrity determination data to the main body 100 of the image forming apparatus.

[00198] If the fourth authentication process is an authentication process to test compatibility, the third data may include table index information previously stored in the image forming apparatus, and the fourth data may be implemented as data including a value corresponding to the index information .

[00199] The interface unit 1410 may be implemented as a block based on a contact or a block based on a connector. The contact based type or communication method of the interface unit 1410 is explained in more detail below.

[00200] As described above, the integrity determination data may be used in part or completely in the authentication or data exchange process depending on exemplary embodiments.

[00201] FIG. 20 illustrates an exemplary method for using integrity determination data in the case of a communication in which recording in an image forming apparatus or an expendable unit is not required. Integrity determination data can be used as part of the authentication process.

[00202] As illustrated in FIG. 20, the main controller 110 and the CRUM module 210 communicate only 8 times for authentication and transmit and verify integrity determination data 4 times during the process.

[00203] The final integrity test is completed in the last authentication process, which is the 8th process, and is not used additionally in the subsequent process, which is the data read / write process. In other words, the integrity testing process is performed only with authentication 1, 2, 7, and 8, and full integrity testing is performed with authentication 7 and 8. In FIG. 20, a signal transmit / receive process may be referred to as a single authentication process. For example, S1510 and S1530 may be the first authentication process, S1550 and S1560 may be the second authentication process, S1570 and S1580 may be the third authentication process, and S1590 and S1620 may be the fourth authentication process.

[00204] As illustrated in FIG. 20, the main controller 110 transmits a signal com-1, which includes data and integrity determination data 1 (S1510). The data includes authentication start command data 1 (authentication command data (CMD) 1), authentication data 1, and SECU1. The authentication initiation command data 1 includes not only the command, but also the data necessary to perform authentication. SECU1 represents indicator information that is provided after the authentication initiation command data 1. The indicator information SECU1 represents a symbol to report the location of the parsing of the integrity determination data in the signal. Indicator information can be represented as a fixed number of bytes. For example, 5 bytes can be used for indicator information. On the other hand, the size of the authentication data 1 may vary according to the content of the data, and accordingly, the size of the integrity determination data 1 may also vary.

[00205] After receiving com-1, the CRUM module 210 performs integrity testing using the integrity determination data 1 included in the signal (S1520). Then, the CRUM module 210 generates integrity determination data 2 using the data to be transmitted and integrity determination data 1 and then transmits a signal com-2, which includes the above data (S1530). The CRUM module 210 performs the function of a consumable unit according to the authentication start command data 1 and configures the authentication data 2 by collecting random data, which are generated, respectively, and data necessary to perform other functions. The CRUM module 210 configures the resulting data 2, which represents the result of the job, which is performed according to the data 1 of the authentication start command. CRUM module 210 transmits com-2, which is a signal including authentication data 2, resultant data 2, SECU2 indicator, and integrity determination data 2 (S1530).

[00206] After receiving com-2, the main controller 110 separates the integrity determination data 2 from the received com-2 and performs integrity testing (S1540).

[00207] If it is determined that an error exists in at least one of the integrity test operations described above (S1520, S1540), the main controller 110 or the CRUM module 210 may terminate the authentication process and determine that the authentication has failed. In this case, the main controller 110 may report authentication failure through the user interface unit 120, which is generated in the main controller 100.

[00208] On the other hand, if the integrity is confirmed, the main controller 110 and the CRUM module 210 sequentially perform subsequent authentication processes.

[00209] In FIG. 20, integrity determination data is not used in the second and third authentication processes. In this case, even if the subsequent authentication task data 3 exists, the main controller 110 transmits com-3, which is a signal including the authentication command 3 and authentication data 3, to the CRUM module 210 without additionally generating integrity data 3 (S1550 )

[00210] When com-3 is received, CRUM module 210 performs the task without performing integrity testing. In particular, the CRUM module 210 transmits com-4, which is a signal including authentication data 4 and resultant authentication data 4, to the main controller 110 (S1560).

[00211] The main controller 110 also transmits com-5, which is a signal including an authentication command 5 and authentication data 5, without performing integrity testing (S1570), and the CRUM module 210 transmits com-6, which is a signal, including authentication data 6 and resultant authentication data 6 (S1580). The second and third authentication processes may be performed without integrity determination data.

[00212] The main controller 110 executes the integrity determination data again in the final authentication process. In other words, the main controller 110 generates integrity determination data 7 using the integrity determination data 1 and 2, which is all existing integrity determination data, along with the authentication command 7, authentication data 7 and SECT7, and transmits com-7, which is a signal including the above data to the CRUM module 210 (S1590).

[00213] The CRUM module 210 ultimately tests the data that is transmitted / received and temporarily stored during the entire communication process using the integrity determination data 7 (S1600). If the integrity is confirmed according to the final test result, the CRUM module 210 determines that the authentication succeeds (S1610) and performs the following process, such as generating data to be transmitted to the image forming apparatus. If there is nothing to write to the storage device during the authentication process, which indicates that there is no temporarily stored data, the data storage operation in the non-volatile storage device (not shown) may be omitted.

[00214] The CRUM module 210 transmits com-8, which is a signal including authentication data 8, resultant authentication data 8, SECT8, and integrity determination data 8, to the main controller 110 (S1620). In order to generate integrity determination data 8, integrity determination data 1, 2 and 7 are used, which are all the data that has been transmitted / received so far.

[00215] The main controller 110 also performs general integrity testing using the integrity determination data SECT8 included in the authentication communication signal 8 received from the CRUM module (S1630). If the integrity is confirmed according to integrity testing (S1640), this becomes an authentication success state, and the main controller 110 performs subsequent operations, such as generating a session key. Similarly, if there is nothing to write to the storage device during the authentication process, which indicates that there is no temporarily stored data, the operation of storing data in a non-volatile storage device (not shown) may be omitted.

[00216] The integrity determination data that is used in this communication process is generated as the previously used integrity determination data, is reflected in an accumulating manner.

[00217] For example, integrity determination data may be processed as follows:

Integrity determination data 1 = E (CMD authentication / authentication data 1 / SECU1)

Integrity determination data 2 = E (authentication data 2 / authentication result 2 / SECU2 / integrity determination data 1)

Integrity determination data T1 = E (authentication CMD 7 / authentication data 7 / integrity determination data 1 / integrity determination data 2)

Integrity determination data T2 = E (authentication data 8 / authentication result 8 / SECT2 / integrity determination data 1 / integrity determination data 2 / integrity determination data T1)

[00218] In the above equations, E () represents a function for obtaining the resulting value by applying a predetermined equation. As illustrated in FIG. 17 and 18, data that is represented as authentication data or an authentication result may include verification data, such as a checksum or MAC, which are used to stabilize a single communication.

[00219] The integrity determination data that is used for part of the authentication process can be configured as illustrated in FIG. 21-24.

[00220] FIG. 21 illustrates the first integrity determination data that the main controller 110 transmits to the CRUM module 210 during the first authentication process. As illustrated in FIG. 21, the main controller 110 generates a new 8-byte value by applying the first 8 bytes and the next 8 bytes of the transmitted data to a particular equation or encryption algorithm and generates the next value by processing the newly generated 8-byte value with the following 8 bytes. Using this method, the main controller 110 may generate integrity determination data by generating an identical equation or algorithm up to SECU1 and temporarily store the generated integrity determination data. If the number of data in the final 8 bytes is not 8 bytes, a specific value, for example, 0x00, can be supplemented to the full 8 bytes, and the operation with insufficient number of bytes can be omitted.

[00221] When the integrity determination data (VC) is generated, if the integrity determination data is SECU, the integrity determination data that was used immediately prior to this should be used. However, the integrity determination data illustrated in FIG. 21 may be transmitted for the first time, and previous integrity determination data is missing. In this case, integrity integrity data can be used, which is initialized as a specific value, for example, 0x00, or the operation can be performed without including previous integrity data. Such conditions may not be applicable if the image forming apparatus and the CRUM module generate integrity data using an identical method.

[00222] If com-1 is received during the first authentication process, the CRUM module tests the CMD and DATA values using the CRC to check whether or not a problem occurs. The CRUM module generates a value according to the method for generating integrity determination data explained in FIG. 21, using the above transmission data including the string SECU1, and compares the value with VC1 included in the signal received in the first authentication process. In other words, the CRUM module 210 generates and compares the integrity determination data similarly to the main controller 110.

[00223] If a problem occurs in the verification of the integrity data, the CRUM module does not perform the following authentication process. In this case, the imaging device can check the error of the CRUM module and, accordingly, can stop or restart the operation. If there are no problems during verification of the integrity data, the imaging device temporarily stores VC1 and performs the following operation.

[00224] The CRUM module 210 performs an authentication operation for encryption according to DATA content and generates com-2 having encryption related data to be used in the image forming apparatus, specific data stored in the CRUM module 210, the CRUM serial number -module and random data as DATA. The CRUM module 210 may be encrypted using an encryption method using all or part of the DATA as a symmetric or asymmetric key. The com-2 content includes DATA, SW, indicating whether the task completed successfully or unsuccessfully, according to the received command, CRC, which is an error detection code, character, VC1 and VC2. In the case of com-2, the character is specified as the string SECU2. Data 2 definitions of integrity, i.e. VC2 can be generated using the method illustrated in FIG. 22.

[00225] As illustrated in FIG. 22, DATA2, SW2, CRC2, SECU2, and VC1 are classified by 8 bytes, and each of the classified data is calculated sequentially using a specific equation or encryption algorithm. The addition can be used depending on the length of the data, thereby forming VC2. The generated VC2 is temporarily stored in the CRUM module 210.

[00226] FIG. 23 and 24 illustrate an exemplary method and configuration for generating integrity determination data that are used in the fourth authentication process.

[00227] For example, in FIG. 20, the main controller 10 uses the integrity determination data in the transmission of com-7, and the CRUM module 210 uses the integrity determination data in the transmission of com-8.

[00228] Com-7 includes a CMD representing com-7, DATA, required for Auth-4 operation, CRC and character string and VC3 indicating the end of communication using integrity determination data. In this case, DATA is encrypted using the session key generated in Auth-1. The character string com-7 is SECT1.

[00229] As illustrated in FIG. 23, VC3 is generated using the lines CMD3, DATA3, CRC3, SECT1 and VC1 and VC2, which are all the integrity determination data that has been generated so far. The main controller 110 temporarily stores the generated VC3. When com-7 is received, the CRUM module 210 generates integrity determination data, similarly to that illustrated in FIG. 23. Since VC1 and VC2 are temporarily stored in CRUM module 110 during the Auth-1 process, integrity determination data that are identical to VC3 can be generated. If a problem arises during the verification of the integrity data, the CRUM module does not perform the following authentication process. In this case, the imaging device can check the error of the CRUM module and, accordingly, can stop or restart the operation.

[00230] If there are no problems with the verification of integrity data, the CRUM module 210 decrypts the DATA as a session key, performs the operations necessary for Auth-4, and generates com-8 data in order to respond to the image forming apparatus. Com-8 includes the DATA, SW, CRC, SECT2 string that is required for Auth-4, and VC4, which is the integrity integrity endpoint. DATA is encrypted as a session key.

[00231] FIG. 24 illustrates an example method and configuration for generating VC4. As illustrated in FIG. 24, CRUM module 210 may generate VC4 by sequentially computing the DATA4, SW4, CRC4, SECT2, and VC1, VC2, VC3 strings by 8 bytes.

[00232] When com-8 is received, the main image forming apparatus controller 110 generates VC4 using the strings DATA4, SW4, CRC4, SECT2 and VC1, VC2, VC3, which are temporarily stored in the main body 100 of the image forming apparatus, and compares them to confirm integrity. If there are no problems during integrity testing, DATA is decrypted as a session key to perform the final authentication operation. Accordingly, when the CRUM module 210 or the consumable unit 200 in which the CRUM module 210 is installed is confirmed to be compatible with the image forming apparatus 100, it is determined that the final authentication completes successfully and a subsequent communication operation can be performed.

[00233] The consumable unit 200 may be removable from the main body 100 of the image forming apparatus. When the consumable unit 200 is installed, it can be electrically connected to the main body 100. Such a connection can be made on the basis of a contact or on the basis of a connector, and communication between the consumable unit 200 and the main body 100 can be performed using the I2C method.

[00234] FIG. 25 illustrates an example of an external configuration of a contact based interface unit 1410. As illustrated in FIG. 25, the consumable unit 200 includes a contact unit 2010 for communication. The main body 100 of the image forming apparatus includes a contact block. When the consumable unit 100 is installed in the main body 100, the interface unit 1410 contacts the contact unit 2010 formed in the main body 100 of the image forming apparatus so that they are electrically connected.

[00235] FIG. 26 illustrates an exemplary connection state between the contact based consumable unit 200 and the main body 100 of the image forming apparatus. FIG. 26 illustrates a contact block 2020, a system board 2040, in which various parts including a main controller 110, and a connection cable 2030 may be arranged to connect the system board 2040 to a contact block 2020. When a consumable unit 200 is installed in the main body 100, as illustrated in FIG. 26, the contact block 2010 formed in the consumable unit 200 is in contact with the main body 100, so that they are electrically connected to each other.

[00236] When the contact blocks are of a contact based type, as illustrated in FIG. 25 and FIG. 26, nothing to fasten the contacting parties. Therefore, if an oscillation of the image forming apparatus occurs, the contact blocks 2010, 2020 may be temporarily separated from each other, which causes communication problems. In other words, if the contact points of the consumable units installed in the image forming apparatus are separated, incorrect data may be transmitted. However, if integrity determination data is used when performing authentication and data exchange as described above, such problems can be resolved. In other words, the main controller 110 or CRUM module 210 can detect an authentication failure or communication error by checking the integrity determination data of the previous data that is received when the contact points are normally connected to each other, and the data that is received while the contact points unstable attached to each other. Accordingly, the operation of reading or writing data cannot be performed, which eliminates the recording of incorrect information in the expendable unit 200.

[00237] FIG. 27 illustrates an exemplary external configuration of a connector based interface unit 1410. Referring to FIG. 27, the consumable unit 200 includes a connector 2210 for communication. Connector 2210 connects to port 2220, which may be located in the main body 100 of the image forming apparatus. When using a connector-based type, contact problems can occur, for example, if foreign matter enters between the connector 2210 and port 2220, or if the attachment unit is damaged when the interface unit 1410 is of a connector-based type, as illustrated in FIG. 27. In this case, an exemplary embodiment of the present invention can prevent an incorrect operation by performing authentication or data exchange using integrity determination data according to various exemplary embodiments.

[00238] The serial communication method may be used for communication between the consumable unit 200 and the main body 100 of the image forming apparatus. For example, an I2C communication method may be used.

[00239] FIG. 28 illustrates exemplary various waveforms that can be transmitted and received between the consumable unit 200 and the main body 100 of the image forming apparatus according to the I2C communication method. The I2C communication method includes VCC and GND, which supply power to the slave device, SCL, which provides a clock signal for synchronization between the main controller 110 and CRUM module 210, SDA, which is an I2C interface data line, etc. In this regard, I2C communication has a simple structure and allows you to connect many blocks to one bus.

[00240] An I2C communication method can be prepared for communication between ICs in a single board circuit, and therefore there is no configuration for checking errors during communication. However, various communication errors may occur during the communication process between the consumable unit and the image forming apparatus.

[00241] Unpredictable resistance may occur, for example, electrical noise interference may occur on the contact surface, dust, toner powder, etc. may affect the communication, or the contact points of the contact surfaces may diverge due to oscillation. Additionally, incorrect transmitted data may be sent in the I2C communication method when the clock signals (SCL) become inconsistent and the transmitted data (SDA) is changed.

[00242] FIG. 29 enlarged illustrates SDA and SCL in the I2C signal of FIG. 28. As illustrated in FIG. 29, the SCL signal has 8 matched high / low signals at once, and 1 byte of data is presented as the high / low signals are generated by SDA, respectively. In other words, a single high / low signal represents 1 bit in SCL or SDA.

[00243] According to method I2C, if a problem occurs during communication, i.e. if there is only 1 bit signal distortion, it is impossible to transmit data normally. For example, if there is a problem in transmitting 4-byte data, 00000000000000000000000000000000 ("0" as a decimal number), and thus only the very first digit of 1 bit is changed, there may be a significant difference when they become 10000000000000000000000000000000 ( "2147483648" as a decimal number).

[00244] However, according to an exemplary embodiment of the present invention, even if this error occurs during communication, data can be tested immediately using integrity determination data that has been transmitted or received previously, and the integrity of all data can also be checked in the final operation using integrity determination data. Accordingly, even if the interface unit 1410 is connected to the main body on the basis of the contact or on the basis of the connector, or the communication between the main body 100 and the consumable unit 200 is carried out according to the I2C communication method, recording of incorrect data due to incorrect authentication or incorrect communication can be prevented.

[00245] A method for authentication and communication according to an exemplary embodiment may be encoded as software, respectively, and recorded on a non-volatile recordable medium. Non-volatile recordable media can be installed in an image forming apparatus, an expendable unit or in a CRUM module and / or in various types of devices, and, accordingly, the above authentication and communication method can be implemented in various devices.

[00246] Non-volatile recordable medium means a medium that can store data semi-permanently instead of storing data for a short time, for example, in a register, cache and memory, and can be read by the device. The above various applications or programs may be stored on and provided on a non-transitory recordable medium such as a CD, DVD, hard disk, Blu-ray disc, USB, memory card and ROM. Although several embodiments of the present invention have been shown and described, those skilled in the art will appreciate that changes can be made in this embodiment without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.

Claims (54)

1. An image forming apparatus comprising: the main body, which includes a main controller, configured to control the operations of the image forming apparatus; a consumable unit that is installed in the main body; and a module for monitoring user-replaceable blocks (CRUM), which stores information regarding the consumable block, the main controller transmits to the CRUM module the first signal containing the first data and the first integrity determination data relative to the first data for authentication with the CRUM module, wherein the CRUM module tests the integrity of the first signal using the first integrity determination data, in response to the first signal received from the main controller, generates the second integrity determination data using the second data to be transmitted to the main controller, and the first integrity determination data , in response to the integrity of the verified first signal, and transmits a second signal containing second data and second integrity determination data to the main controller. 2. The imaging device according to claim 1, in which the main controller and the CRUM module authenticate through a variety of authentication processes, the main controller generates the third integrity determination data using the third data, the first integrity determination data and the second integrity determination data in the final authentication process from the plurality of authentication processes and transmits a third signal to the CRUM module, which includes the third data and third data determination of integrity wherein the CRUM module finally tests the third signal using the third integrity determination data, in response to receiving the third signal, generates the fourth integrity determination data using the fourth data and the first to third integrity determination data, in response to the integrity of the verified third signal, and transmits a fourth signal, which includes fourth data and fourth integrity determination data, to a main controller, wherein the main controller finally tests the fourth signal using the fourth integrity determination data in response to the received fourth signal. 3. The image forming apparatus of claim 2, wherein the plurality of authentication processes includes a first authentication process, in which the main controller and the CRUM module transmit and receive a first signal and a second signal and generate a session key, respectively, a second authentication process for synchronization the first table stored in each of the main body of the image forming apparatus and the CRUM module, the third authentication process for synchronizing the second table stored in each of the main body of the mouth oystva imaging and CRUM-module, and the fourth authentication process, wherein the master controller module and CRUM-transmitting and receiving the third signal and the fourth signal and determining compatibility between the imaging device and the CRUM-module. 4. The imaging device according to claim 2, wherein the main controller and the CRUM module store integrity determination data used for the plurality of authentication processes, respectively, and exchange data in response to the completed authentication. 5. CRUM-module, interacting with the device imaging, containing: an interface unit that receives a first signal including first data and first integrity determination data with respect to the first data from the main body of the image forming apparatus; a testing unit that tests signal integrity using the first integrity determination data; a forming unit that generates integrity determination data; and a controller that controls the actions of the testing unit and the formation unit, wherein the controller controls the forming unit to generate second integrity determination data using the second data to be transmitted to the main body of the image forming apparatus and the first integrity determination data in response to the integrity of the first signal including the first integrity determination data verified by the testing unit, and transmits a second signal including second data and second integrity determination data to the main body of the formation device from images through the interface unit. 6. The CRUM module according to claim 5, further comprising: a storage unit for storing the first integrity determination data and the second integrity determination data. 7. The CRUM module according to claim 6, in which the controller controls the testing unit for final testing of the third signal using the third integrity determination data, in response to receiving the third signal including the third data and the third integrity determination data with respect to the third data, a forming unit for generating fourth integrity determination data using fourth data to be transmitted to the main body of the image forming apparatus, and from the first to eti definition data integrity in response to the verified integrity of the third signal, and transmits a fourth signal which includes the fourth data and the fourth data determining integrity on the main body of the image forming apparatus through the interface unit. 8. The CRUM module according to claim 6, in which the controller generates a session key using the first data and second data, and in response to the completion of the formation of the session key, performs an authentication process to synchronize the first table stored in each of the main body of the image forming apparatus and A CRUM module, an authentication process for synchronizing a second table stored in each of the main body of the image forming apparatus and a CRUM module, and an authentication process for determining compatibility between devices m and imaging CRUM-module based on at least a first table and a second table. 9. The CRUM module of claim 8, wherein the controller, during the authentication process to determine compatibility, controls the testing unit to perform final testing for all of the multiple authentication processes using third integrity determination data, in response to receiving a signal including third integrity determination data, including both first and second integrity determination data, from the main body, and controls the forming unit to generate fourth integer determination data stities, which include first to third integrity determination data, in response to a final test result showing data integrity, and transmits a signal including fourth integrity determination data to the main body via an interface unit. 10. An authentication method for an image forming apparatus, comprising the steps of: generating the first integrity determination data with respect to the first data by means of a main controller mounted on the main body of the image forming apparatus for authentication with a CRUM module; transmit through the main controller to the CRUM module the first signal, which includes the first data and the first integrity determination data; test the integrity of the first signal using a CRUM module using the first integrity determination data; generating by the CRUM module the second integrity determination data using the second data to be transmitted to the main controller and the first integrity determination data in response to the integrity of the verified first signal; and transmit by the CRUM module a second signal, which includes second data and second integrity determination data, to the main controller. 11. The method according to p. 10, further comprising stages in which: generating third integrity determination data by means of the main controller using the third data, first integrity determination data and second integrity determination data, and transmitting to the CRUM module a third signal, which includes third data and third integrity determination data; the third signal is finally tested using the CRUM module using the third integrity determination data, the fourth integrity determination data is generated using the fourth data and the first to third integrity determination data, in response to the integrity of the verified third signal, and the fourth signal is transmitted, which includes fourth data and fourth integrity determination data to the main controller; and the fourth signal is finally tested by the main controller using the fourth integrity determination data in response to the received fourth signal. 12. The method according to p. 11, further comprising stages in which: the authentication process for synchronizing the first table stored in each of the main body of the image forming apparatus and the CRUM module is performed by the main controller, and the authentication process for synchronizing the second table stored in each of the main body of the image forming apparatus and the CRUM module after receiving the second signal and before transmitting the third signal, wherein the first and second data are data for generating a session key, and the third and fourth data are data for determining the integrity between the main body of the image forming apparatus and the CRUM module. 13. An authentication method for a CRUM module configured to communicate with an image forming apparatus, comprising the steps of: receive from the main body of the image forming apparatus a first signal including first data and first integrity determination data with respect to the first data; testing the integrity of the first signal using the first integrity determination data; generating second integrity determination data using the second data to be transmitted to the main body of the image forming apparatus and the first integrity determination data; and transmitting a second signal including second data and second integrity determination data to the main body of the image forming apparatus. 14. The method of claim 13, further comprising the step of: store the first and second integrity determination data. 15. The method of claim 14, further comprising the steps of: finally testing the third signal using the third integrity determination data in response to the third signal including the third data and third integrity determination data with respect to the third data received from the main body of the image forming apparatus; generating fourth integrity determination data using fourth data to be transmitted to the main body of the image forming apparatus, and first to third integrity determination data, in response to the integrity of the verified third signal; and transmitting a fourth signal, which includes fourth data and fourth integrity determination data, to the main body of the image forming apparatus. 16. The method according to p. 14, further comprising stages in which: generating a session key using the first data and second data; and in succession, in response to the completion of the formation of the session key, the authentication process for synchronizing the first table stored in each of the main body of the image forming apparatus and the CRUM module, the authentication process for synchronizing the second table stored in each of the main body of the image forming apparatus and CRUM module, and the authentication process for determining compatibility between the imaging device and the CRUM module based on at least the first table and the second tables. 17. The method of claim 16, wherein the authentication process for determining compatibility includes the steps of: finally testing the whole set of authentication processes using third integrity determination data in response to receiving a signal including third integrity determination data including both first and second integrity determination data from the main body; in response to the final testing result showing the integrity of the data, the fourth integrity determination data is generated, which include first to third integrity determination data; and transmitting a signal including fourth integrity determination data to the main body.

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