PRINTING DEVICES TO CONTROL ACCESS TO DATA

An example printing device includes: printing components; a communication interface to communicate with a server; a memory storing a cryptographic key and a device identifier; and a processor connected to the printing components, the communication interface and the memory, the memory further storing instructions, the processor to execute the instructions. The instructions are to: generate usage data indicative of usage of the printing components. The instructions are further to: encrypt the usage data using the cryptographic key to generate encrypted usage data. The instructions are further to: transmit, using the communication interface, the encrypted usage data to the server for storage with the device identifier. The instructions are further to: receive a request to transmit the cryptographic key to the server to decrypt the encrypted usage data. The instructions are further to: in response, transmit, using the communication interface, the cryptographic key to the server with the device identifier.

BACKGROUND

Managed services for printing devices may be provided by an entity which may maintain the printing devices of a company and the like once an agreement is reached to do so. However, prior to reaching an agreement, the company that owns or leases the printing devices first engages the entity offering the managed services such that the entity can provide an offer. However, the entity must first gain access to the printing devices (e.g. after being contacted by the company that owns or leases the printing devices) to install software which, during an assessment period, causes the printing devices to transmit usage data to a central server of the entity, so that the managed services to be provided to the printing devices can be assessed. Such managed services may include device maintenance and replacing consumables at the printing devices. Such an approach introduces significant delay in providing the managed services, which can lead to improper maintenance of the printing devices and/or consumables not being replaced in a timely fashion, each which can lead to the printing devices becoming at least partially inoperable.

DETAILED DESCRIPTION

Managing a fleet of printing devices may present a challenge. For example, staff at a company may purchase or lease a fleet of printing devices and attempt to manage the printing devices in-house. After a time, however, such management may become unwieldy and/or outside the purview of the staff of the company, who may waste their time to troubleshooting printers and replacing consumables (e.g. printing cartridges, paper, etc.). As such, a managed printing services entity may be engaged to manage the fleet of printing devices; however, before such an entity provide such managed services, the printing services entity may study the fleet of printing devices during an assessment period to determine a level of managed service that may be needed, and a commensurate cost for such managed services. Such an assessment period, which may occur by installing software on the printers after the printing services entity is contacted by the company that owns and/or leases the printing devices, may delay the rollout of the managed services which may lead to the printing devices being improperly serviced by the company that owns/leases the printing devices, and/or further waste the time of IT staff, and the like, maintaining the printing devices.

Hence, provided herein is a printing device which may have preinstalled software to transmit encrypted data indicative of usage of printing components to a server of a printing services entity. The printing device generally encrypts the data indicative of usage of printing components. The encrypted data may be decrypted using a cryptographic key which may be generated by the printing device, for example when first powered on, and which is hence unknown to the server. The cryptographic key may the same key used to encrypt the data, or a complementary key. In some examples, the printing device may transmit the encrypted data indicative of usage of printing components, to the server, when permission to do is so is received at the printing device, for example via input received at an input device. The server receives and stores the encrypted data indicative of usage of printing components, but cannot decrypt the encrypted data until permission is received to obtain the cryptographic key. Indeed, when permission is received, the printing device transmits the cryptographic key to the server. Once the cryptographic key is received, for example when a company that is operating the printing device engages the printing services entity, the server may decrypt the data indicative of usage of printing components and determine usage of the printing components without having to go through an assessment period.

Referring toFIG. 1, a printing device101to control access to data is depicted. The printing device101comprises: printing components103; a communication interface105to communicate with a server (not depicted); a memory112storing a cryptographic key114and a device identifier116; and a processor120connected to the printing components103, the communication interface105and the memory112, the memory112further storing instructions136, the processor120to execute the instructions136. The instructions136are to: generate usage data indicative of usage of the printing components103; encrypt the usage data to generate encrypted usage data; transmit, using the communication interface105, the encrypted usage data to the server for storage with the device identifier116; receive a request to transmit the cryptographic key114to the server to decrypt the encrypted usage data, the cryptographic key114to decrypt the encrypted usage data; and, in response, transmit, using the communication interface105, the cryptographic key114to the server with the device identifier116.

The printing device101may include additional components, such as various additional interfaces and/or input/output devices such as display screens to interact with a user or an administrator of the printing device101. The printing device101may be to generally print printed materials using the printing components103which may include, but are not limited to, print heads, printing cartridges, mechanical components such as feed mechanisms (e.g. for paper), and the like.

The communication interface105is to communicate with the server, for example via a network, such as a wired or wireless network which may include one or more of the Internet, a cellular network, a WiFi network, and the like.

In addition, the printing device101may communicate with an other device and/or server (e.g. different from the server receiving encrypted usage date), via the communication interface105, or another communication (and/or network) interface, to receive print jobs to print printed materials at the printing device101using the printing components103. Such communication may occur via one or more of the Internet, a cellular network, a WiFi network, a Bluetooth™ network, a Zigbee™ networks, a local area network (LAN), and the like.

The memory112is coupled to the processor120and includes a non-transitory machine-readable storage medium that may be any electronic, magnetic, optical, or other physical storage device. The non-transitory machine-readable storage medium of the memory112may include, for example, random access memory (RAM), electrically-erasable programmable read-only memory (EEPROM), flash memory, a storage drive, an optical disc, and the like. The memory112may also be encoded with executable instructions to operate the communication interface105and other hardware in communication with the processor120. In other examples, it is to be appreciated that the memory112may be substituted with a cloud-based storage system. Indeed the non-transitory machine-readable storage medium of the memory112is generally encoded with the instructions136executable by the processor120of the printing device101.

The non-transitory machine-readable storage medium of the memory112may include, for example, random access memory (RAM), electrically-erasable programmable read-only memory (EEPROM), flash memory, a storage drive, an optical disc, and the like. The memory112may also be encoded with executable instructions to operate the communication interface105and other hardware in communication with the processor120. In other examples, it is to be appreciated that the memory112may be substituted with a cloud-based storage system.

The memory112may also store an operating system that is executable by the processor120to provide general functionality to the printing device101, for example, functionality to support various applications such as a user interface to access various features of the printing device101. Examples of operating systems include Windows™, macOS™, iOS™, Android™, Linux™, and Unix™. The memory112may additionally store applications that are executable by the processor120to provide specific functionality to the printing device101, and which may include the instructions136.

The processor120may include a central processing unit (CPU), a microcontroller, a microprocessor, a processing core, a field-programmable gate array (FPGA), an application-specific integrated circuit (ASIC) or similar. The processor120and memory112may cooperate to execute various instructions such as the instructions136.

Accordingly, the processor120may execute instructions stored on the memory112to implement print jobs to print the printed materials using the printing components103; such instructions may be in addition to the instructions136and/or a component of the instructions136. Regardless, the processor120monitors the printing components103to determine data indicative of usage of the printing components103. Such data indicative of usage of the printing components103may include, but is not limited to, one or more of: a frequency that a printing cartridge is replaced; a rate of use of ink, and the like, at a printing cartridge; frequency and/or rate of print jobs; numbers of print jobs as a function of time; a frequency of jamming and/or breakage of mechanical components, such as feed mechanisms, and the like.

Indeed, the data indicative of usage of the printing components103may be generally used to determine a maintenance schedule of the printing device101, which may include, but is not limited to, a schedule to replace printing cartridges (e.g. before ink runs out), a schedule to replace paper, a schedule to replace mechanical components, a schedule to clean and/or service a print head, a recommendation for a different printing device (e.g. as the printing device101may not meet the needs of a company and/or entity using the printing device101), and the like.

Such the usage data may include, but is not limited to, print job level usage data (e.g. a type of a print job, a number of pages of the print job) and which may also include a timestamp of each print job.

Hence, the processor120and/or the instructions136may be further to: monitor the usage of the printing components103by monitoring usage of consumables (e.g. paper, printing cartridges) by the printing components103or a number of times the printing components103are used as a function of time.

The cryptographic key114may include any suitable cryptographic key including, but not limited to, a symmetric key, and the like. In these examples, processor120and/or the instructions136may be further to: encrypt the usage data, indicative of usage of the printing components103, using the cryptographic key114. Hence, in these examples, the cryptographic key114may be to both encrypt and decrypt the usage data.

In some of these examples, the processor120and/or the instructions136may be further to: generate the cryptographic key114when the printing device101is first powered on; and store the cryptographic key114in the memory112. For example, the instructions136may be further to generate the cryptographic key114from a MAC (media access control) address, and the printing device101and/or the device identifier116and/or using a time and/or date, and the like.

Indeed, the device identifier116may comprise one or more of: a MAC address of the printing device101, a serial number of the printing device101, an internet protocol (IP) address of the printing device101, the like.

However, in some examples, the cryptographic key114may be asymmetric and include a public key of a private/public key pair, (e.g. as issued by a certificate authority, and the like). In these examples, the memory112may store the private key, complementary to the public key, and the processor120and/or the instructions136may be to further to encrypt the usage data using the private key. In some of these examples, the processor120and/or the instructions136may be further to communicate with a certificate authority to obtain the digital certificate signed by the private key, the digital certificate including the public key. In these examples, the private key (and optionally the public key, which may be obtained by the printing device101after shipping) may be stored in the memory112in a factory setting, for example, in a secure manner such that the manufacturer of the printing device201does not have access to the private key.

Regardless, the processor120generally encrypts the data indicative of usage of the printing components103and transmits the encrypted data to the server for storage, and the cryptographic key114is for decrypting the encrypted data.

In some of these examples, for example, where the cryptographic key114is symmetric, the processor120and/or the instructions136may also be to: generate the cryptographic key114and a control code when the printing device101is first powered on; store the cryptographic key114in the memory112in association with the control code; and receive the control code with the request to transmit the cryptographic key114to the server, the cryptographic key114and the device identifier116being transmitted when the control code received with the request matches the control code stored in the memory112.

For example, the control code may comprise random alphanumeric text and/or a random number, and the like, generated by the processor120. The control code may be provided to the server as authorization and/or permission for the server to decrypt the previously received encrypted data indicative of usage of the printing components103, for example to generate an assessment of the usage data, and the like, for servicing the printing device101.

However, in other examples, the memory112may further store a control code in association with the cryptographic key114regardless of whether the cryptographic key114is symmetric or asymmetric. For example the control code may be received at an input device of the printing device101, for example when the printing device101is first powered on and stored in association with the cryptographic key114. For example, a user of the printing device101may be prompted to enter a control code via the input device. Alternatively, the control code may be generated by the processor120and stored in association with the cryptographic key114; in these examples, the control code may be generated by the processor120and rendered at a display screen of the printing device101such that a user of the printing device101may record the control code for later usage in an authorization procedure.

In yet further examples, the printing device101may further comprise an input device, and the memory112may further store a control code in association with the cryptographic key114. In some of these examples, the processor120and/or the instructions136may be are further to: receive the request to transmit the cryptographic key114by receiving the control code via the input device, for example, in an authorization procedure to transmit the cryptographic key114to the server, such that the server may decrypt the previously received encrypted data indicative of usage of the printing components103.

However, the user of the printing device101may contact a user of the server and provide the user of the server with the control code for input at the server. In these examples, the processor120and/or the instructions136may also be to: receive the request to transmit the cryptographic key114to the server by receiving the control code via the communication interface105.

Hence, the processor120and/or the instructions136may be further to: receive a control code associated with the cryptographic key114, the control code received via the communication interface105or an input device of the printing device101.

However, in yet further examples, an employee, and the like, of the entity operating the server to which the encrypted usage data is transmitted by visit the company operating the printing device101and collect the device identifier116and optionally the control code. Indeed, when the company is operating a plurality of printing devices, the employee may collect respective device identifiers (and, optionally, associated control codes) from each of the plurality of printing devices. For example, each of the plurality of printing devices may be operated to print a respective device identifier and control code. The employee may then enter the respective device identifiers (and control codes) at the server which transmits a request for a respective cryptographic key to each of the plurality of printing devices.

In some examples, prior to the encrypted data being generated and transmitted, permission to do so is received at the printing device101. For example, the processor120and/or the instructions136may be further to, when printing device101is first powered on: provide, at a display screen of the printing device101, rendered data indicative of requesting permission to transmit the encrypted usage data to the server; and receive, via an input device, input indicative of permission to transmit the encrypted usage data to the server, the encrypted usage data being generated and transmitted after receiving the input indicative of permission.

FIG. 2depicts a schematic block diagram of a system200that includes a printing device201similar to the printing device101, with like components having like numbers, but in a “200” series rather than a “100” series. Hence, the printing device201comprises: printing components203; a communication interface205to communicate with a server206; a memory212storing a cryptographic key214(e.g. in association with a control code215) and a device identifier216; and a processor220connected to the printing components203, the communication interface205and the memory212, the memory212further storing instructions236, the processor220to execute the instructions236. The instructions236are to: generate usage data indicative of usage of the printing components203; encrypt the usage data to generate encrypted usage data; transmit, using the communication interface205, the encrypted usage data to the server206for storage with the device identifier216; receive a request to transmit the cryptographic key214to the server206to decrypt the encrypted usage data, the cryptographic key214to decrypt the encrypted usage data; and, in response, transmit, using the communication interface205, the cryptographic key214to the server206with the device identifier216.

The control code215may be used to provide authorization for the server206to receive the cryptographic key214, as described in further detail below. The association between the cryptographic key214and the control code215at the memory212is depicted inFIG. 2via a dashed line therebetween. The cryptographic key214and the control code215may be stored and/or generated in any suitable manner, for example as described above with respect to the printing device101.

As depicted, the printing device201further comprises an input device237and a display screen238which may be used as a human/machine interface to the printing device201. The input device237may include a touchscreen, alphanumeric keypad, and the like, and the display screen238may include any suitable flat panel display screen and/or the touchscreen of the input device237. Indeed, when the display screen238comprises the touchscreen of the input device237, the display screen238and the input device237may be combined. The input device237and the display screen238may hence be used by a user of the printing device201to enter and/or view the control code215, as described above, and/or to print the device identifier216and the control code215.

A chassis239of the printing device201is also depicted inFIG. 2. In particular, the chassis239has a configuration of a printer in which paper is fed from an upper tray through a feed mechanism and out onto a lower tray. However, the depicted configuration of the chassis239is merely an example, and the chassis239and/or the printing device201may have any suitable printer configuration.

The system200further comprises the server206in communication with the printing device201via a communication network240(interchangeably referred to hereafter as the network240). Furthermore, communication links between the various components of the system200are depicted as double-ended arrows, and which may be wired or wireless as desired.

While only one printing device201is depicted inFIG. 2, the system200may comprise a plurality of printing devices (including the printing device201) in communication with the server206, including, but not limited to a fleet of printing devices purchased and/or leased by a company to provide printing functionality to employees, and the like. However, the plurality of printing devices201may include printing devices of a plurality of companies and/or entities, for example different companies, and the like.

The server206may comprise a server device, a computing device, a cloud computing device, and the like, associated with an entity offering managed printing services, for example, to the entity operating the printing device101. Furthermore, the server206may be embodied in a plurality of computing devices, for example in a cloud computing environment.

The server206generally comprises: a communication interface255to communicate with a printing device201; and a processor270connected to the communication interface255and a memory272, the processor270to execute instructions286stored in the memory272, the instructions286to: receive, via the communication interface255, from the printing device201, encrypted usage data of the printing device201, the encrypted usage data comprising an encrypted version of usage data indicative of usage of the printing components203of the printing device201; store the encrypted usage data in a storage device289in association with a device identifier216of the printing device201; transmit, via the communication interface255, to the printing device201, a request for the cryptographic key214for decrypting the encrypted usage data; receive, via the communication interface255, from the printing device201, the cryptographic key214; decrypt the encrypted usage data using the cryptographic key214to generate the usage data; generate an assessment of the usage data; and delete the cryptographic key214and the usage data.

The communication interface255, the processor270, the memory272and the input device297may be respectively similar to the communication interface205, the processor220, the memory222and the input device237, but adapted for the functionality of the server206. The server206may include other components, not depicted, such as a display screen and the like. Furthermore, the input device237may be external to the server206, and may be a component of a terminal to access the server206.

As depicted, the storage device289comprises a cloud storage device and/or database accessible to the server206. As depicted, the server206is in local communication with the storage device289, for example via cables, a local area network, and the like. However in other examples the server206may be in communication with the storage device289via the network240. In yet further examples, the server206may comprise the storage device289(e.g. the memory272may comprise the storage device289).

The server206is generally to store encrypted data received from the printing device201at the storage device289, in association with the device identifier216. However, prior to access being granted to the encrypted data, the server206does not have access to the unencrypted data. When such access is granted, for example, by receiving the device identifier216and/or the control code215, the server206is to request and/or received the cryptographic key214from the printing device201to decrypt encrypted data received from the printing device201.

For example, the processor270and/or the instructions286may be further to: receive the control code215associated with the cryptographic key214; and transmit the request for the cryptographic key214, the request including the control code215.

For example, as depicted, the processor270is further in communication with the input device297(e.g. a keyboard, and the like, which may be external to the server206). In these examples, the processor270and/or the instructions286may be further to: receive, using the input device297, the control code215associated with the cryptographic key214; and transmit the request for the cryptographic key214, the request including the control code215. For example, a user of the printing device201may communicate the control code215to a user of the server206to authorize the user of the server206to input the control code215into the server206using the input device297to, in turn, authorize the server206to access the encrypted data as stored at the storage device289. Alternatively, a user of the server206may visit the printing device201and collect the control code215(and/or the device identifier216) therefrom, as described below.

In some examples, processor270and/or the instructions286may be further to: generate the assessment of the usage data based on indications of usage of consumables at the printing device201, as stored in the usage data, or a number of times the printing components203are used as a function of time, as stored in the usage data. Hence, the assessment of the usage data may include a proposal for providing printer services for the printing device201that takes such factors into account.

In some examples, processor270and/or the instructions286may be further to: receive, via the communication interface255, from the printing device201, after deleting the cryptographic key214and the usage data, further encrypted usage data in association with the device identifier216, the further encrypted usage data comprising a further encrypted version of further usage data indicative of further usage of the printing components203of the printing device201. Hence, the server206may continue to receive encrypted usage data, which may be combined with the encrypted usage data already received, for example for use in later assessments of usage of the printing device201.

Referring toFIG. 3, a flowchart of a method300for controlling access to data is depicted. In order to assist in the explanation of method300, it will be assumed that method300may be performed with the printing device201, and specifically by the processor220implementing the instructions236. Indeed, the method300may be one way in which printing device201may be configured to interact with the server206. Furthermore, the following discussion of method300may lead to a further understanding of the processor220, the printing device201, the server206, the system200, and their various components. Furthermore, the method300may be performed with the printing device101, and for example by the processor120implementing the instructions136. Furthermore, it is to be emphasized, that method300may not be performed in the exact sequence as shown, and various blocks may be performed in parallel rather than in sequence, or in a different sequence altogether.

Beginning at a block301, the processor220generates usage data indicative of usage of the printing components203, as described above.

At a block303, the processor220encrypts the usage data to generate encrypted usage data, as described above.

At a block305, the processor220transmits, using the communication interface205, the encrypted usage data to the server206for storage with the device identifier216.

In some examples, the processor220transmits the encrypted usage data to the server206periodically, for example once per day, once per week, and the like, accumulating such encrypted usage data in between transmissions. In other examples, the processor220transmits the encrypted usage data to the server206as the usage data is generated.

In some examples, the processor220transmits the encrypted usage data to the server206with the device identifier216with each transmission. However, in other examples, the processor220registers the printing device201with the server206, including the device identifier216and an internet protocol address, and the like, of the printing device201(e.g. when the device identifier216is different from the internet protocol address); hence, when the server206later receives the encrypted usage data from the registered internet protocol address (e.g. without the device identifier216) the server206may store the encrypted usage data at the storage device289in association with the previously registered device identifier216.

At a block307, the processor220determines whether a request to transmit the cryptographic key214to the server206has been received, the request to decrypt the encrypted usage data, the cryptographic key214to decrypt the encrypted usage data. As depicted, the request may include receiving a control code which may be compared with the control code215stored in the memory222.

When a request is not received, or the control code received with a request does not match the control code215stored in the memory222(e.g. a “NO” decision at the block307) the processor220continues to generate, encrypt and transmit usage data to the server206at the blocks301,303,305.

However, when a request is received, and/or the control code received with a request matches the control code215stored in the memory222(e.g. a “YES” decision at the block307) in response, at a block309, the processor220transmits, using the communication interface205, the cryptographic key214to the server206with the device identifier216.

Hence, the server206may decrypt the previously received encrypted usage data to generate an assessment of the usage data, without introducing an assessment period that begins with installing software at the printing device201to transmit the usage data. Furthermore, such a method300preserves the privacy of the usage data as the server206, while receiving and storing the encrypted usage data, does not have access to the unencrypted usage data until permission is received to do so.

Indeed, referring toFIG. 4, a flowchart of a method400for controlling access to data at the server206is depicted. In order to assist in the explanation of method400, it will be assumed that method400may be performed with the server206, and specifically by the processor270implementing the instructions286. Indeed, the method400may be one way in which the server206may be configured to interact with the printing device201. Furthermore, the following discussion of method400may lead to a further understanding of the processor270, the server206, the printing device201, the system200, and their various components. Furthermore, it is to be emphasized, that method400may not be performed in the exact sequence as shown, and various blocks may be performed in parallel rather than in sequence, or in a different sequence altogether.

Beginning at a block401, the processor270receives, via the communication interface255, from the printing device201, encrypted usage data of the printing device201, the encrypted usage data comprising an encrypted version of usage data indicative of usage of the printing components203of the printing device201, as described above.

At a block403, the processor270stores the encrypted usage data in a storage device289in association with the device identifier216.

At a block405, the processor270transmits, via the communication interface255, to the printing device201, a request for the cryptographic key214for decrypting the encrypted usage data. The request may include the device identifier216received from the printing device201and/or via the input device297. The request may further include the control code215received from the printing device201and/or via the input device297.

At a block407, the processor270receives, via the communication interface255, from the printing device201, the cryptographic key214. The cryptographic key214is generally received in response to transmitting the request of the block405.

At a block409, the processor270decrypts the encrypted usage data using the cryptographic key214to generate the usage data. Hence, the processor270now has access to the usage data as generated at the printing device201.

At a block411, the processor270generates an assessment of the usage data, as described elsewhere in the present specification.

At a block413, the processor270deletes the cryptographic key214and the usage data.

Hence, the server206receives the encrypted usage data, for example before being engaged by the company operating the printing device201but does not have access to the unencrypted usage data until permission is received to do so, for example when the cryptographic key214is received. The server206may then decrypt the encrypted usage data to generate the assessment without introducing an assessment period that begins with installing software at the printing device201to transmit the usage data. Furthermore, once the server206has decrypted the encrypted usage data to generate the assessment, the usage data (e.g. as decrypted) and the cryptographic key214are deleted, for example to continue to preserve the privacy of the usage data. The method400may continue to be implemented after the usage data and the cryptographic key214are deleted, for example to again generate an assessment of usage data at a later time based on the encrypted usage data previously received and stored in the storage device289, and further encrypted usage data received as the method400continues to be implemented. In some examples, however, historic encrypted usage data stored in the storage device289may be deleted after a given period of time, for example to store the encrypted usage date only for a given period of time (e.g. a year and/or a time period configurable by an administrator of the server206).

Attention is next directed toFIG. 5toFIG. 9which depicts an example of the method300and the method400. For example,FIG. 5toFIG. 9each depicts the system200, however not all components of the printing device201and the server206are shown. Such components are, however, present (e.g. the processors220,270, etc. are present at the printing device201and the server206). Furthermore, inFIG. 5toFIG. 9, the processor220of the printing device201is implementing the instructions236, and the processor270is implementing the instructions286.

Attention is first directed toFIG. 5which depicts an interaction with the display screen238, for example when the printing device201is first powered on. In particular, the processor220may control the display screen238to provide a selectable option as to whether encrypted usage data is to be transmitted to the server206. As depicted, a user of the printing device201has interacted with display screen238(e.g. via a touch screen) to select “Y” that, yes, the encrypted usage data is to be transmitted to the server206.

As such, the printing device201is depicted as generating (e.g. at the block301of the method300) usage data501of the printing components203, encrypting (e.g. at the block303of the method300) the usage data501using the cryptographic key214to generate encrypted usage data503, and transmitting (e.g. at the block305of the method300) the encrypted usage data503to the server206. As depicted, the encrypted usage data503is transmitted with the device identifier216.

As also depicted inFIG. 5, the server206is receiving (e.g. at the block401of the method400) the encrypted usage data503, and storing e.g. at the block403of the method400) at the storage device289, for example in association with the device identifier216.

Attention is next directed toFIG. 6which depicts another interaction with the display screen238for example after a period of time during which the printing device201has been transmitting the encrypted usage data503to the server206. In this example, via a user of the printing device201interacting with a menu system provided at the display screen238, the processor220may control the display screen238to provide a selectable option to request printing of the device identifier216and optionally the control code215. As depicted, a user of the printing device201has interacted with display screen238(e.g. via a touch screen) to select “Y” that, yes, printing of the device identifier216and optionally the control code215is to occur. In some examples (not depicted), the processor220may request entry of the control code215(and/or a password) for further authorization.

As such, as also depicted inFIG. 6, the printing device201prints a page601that includes the device identifier216and optionally the control code215. As depicted, the device identifier216and optionally the control code215are entered and/or received at the server206, for example using data entry techniques using the input device297. Alternatively, the device identifier216and optionally the control code215may be transmitted as a message to the server206(e.g. via an email, and the like transmitted from a communication device of a user of the printing device201, and the like). Alternatively, the printing device201may be controlled to transmit an authorization of assessment of the usage data501to the server206that includes the device identifier216and optionally the control code215

Regardless, the server206receives the device identifier216and optionally the control code215. As depicted, in response, the server206is transmitting (e.g. at the block405of the method400) a request603for the cryptographic key214the printing device201, the request603including the control code215. As also depicted inFIG. 6, the printing device201is receiving the request603(e.g. at the block307of the method300) and determines that the control code215in the request603matches the control code215as stored in the memory222.

As such, inFIG. 7, the printing device201is depicted as transmitting (e.g. at the block309of the method300) the cryptographic key214to the server206, for example in association with the device identifier216. The server206is receiving (e.g. at the block407of the method400) the cryptographic key214. The server206may use the device identifier216to retrieve the encrypted usage data503from the storage device289. The server206is further depicted as decrypting (e.g. at the block409of the method400) the encrypted usage data503, using the cryptographic key214, to generate the usage data501.

Attention is directed toFIG. 8which depicts the server206generating (e.g. the block411of the method400) an assessment801of the usage data501, which may include, but is not limited to, a schedule for servicing the printing device201, as well as associated costs.

FIG. 9further depicts the server206deleting (e.g. the block413of the method400) the cryptographic key214and the usage data501to preserve the privacy of the encrypted usage data501stored at the storage device289.

In general, the assessment801may be transmitted to a communication device associated with a user and/or administrator of the printing device201to determine whether the entity associated with the server206is to be engaged for printing manage services. Deletion of the cryptographic key214and the usage data501may ensure ongoing privacy of the usage data of the printing device201.

While present examples are described with respect to the server206collecting encrypted usage data for one printing device, present examples include the server206collecting encrypted usage data for a plurality of printing devices, such that the method300may be implemented at the plurality of printing devices, and the server206may implement the method400to generate an assessment of usage data for the plurality of printing devices, based on encrypted usage data and respective cryptographic keys received from each of the plurality of printing devices. In this manner, the assessment generated at the block411of the method400may include a proposal for providing printer services for all of the plurality of printing devices.

It should be recognized that features and aspects of the various examples provided above may be combined into further examples that also fall within the scope of the present disclosure.