Patent Publication Number: US-8112116-B2

Title: Bidirectional dynamic offloading of tasks between a host and a mobile device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This patent application is a continuation of, and claims priority from, U.S. patent application Ser. No. 11/670,891 filed on Feb. 2, 2007, which is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND 
     Today&#39;s mobile devices often have advanced processing power and specialized circuitry. An example of such specialized circuitry includes a Digital Signal Processor (DSP) in a mobile phone. Mobile devices may be connected to a host, such as a personal computer, for exchanging data between the mobile device and the host. However, current designs do not consistently allow for host workflows to be performed by the computational resources of a connected mobile device and in cases of traditionally constrained devices (like flash memory drives) make it almost impossible. 
     SUMMARY 
     The following presents a simplified summary of the disclosure in order to provide a basic understanding to the reader. This summary is not an extensive overview of the disclosure and it does not identify key/critical elements of the invention or delineate the scope of the invention. Its sole purpose is to present some concepts disclosed herein in a simplified form as a prelude to the more detailed description that is presented later. 
     Embodiments of the invention provide offloading of tasks between a host and a mobile device. In one embodiment, a host may use a function of a mobile device to perform host tasking. The processing power and dedicated circuitry of a connected mobile device may be exploited by the host system to optimize the workflow of the host system. In another embodiment, a mobile device may offload device tasking to a host. 
     Many of the attendant features will be more readily appreciated as the same become better understood by reference to the following detailed description considered in connection with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Like reference numerals are used to designate like parts in the accompanying drawings. 
         FIG. 1  is a block diagram of a host connected to a mobile device in accordance with an embodiment of the invention. 
         FIG. 2  is a block diagram of a mobile device in accordance with an embodiment of the invention. 
         FIG. 3  is a flowchart showing the logic and operations of a host offloading a task to a mobile device in accordance with an embodiment of the invention. 
         FIG. 4  is a block diagram of exposing device functions in accordance with an embodiment of the invention. 
         FIG. 5  is a block diagram of exposing device functions in accordance with an embodiment of the invention. 
         FIG. 6  is a block diagram of exposing device functions in accordance with an embodiment of the invention. 
         FIG. 7  is an array for exposing device functions in accordance with an embodiment of the invention. 
         FIG. 8  is a flowchart showing the logic and operations of a mobile device offloading a device task to a host in accordance with an embodiment of the invention. 
         FIG. 9  is a block diagram of an example computing device for implementing embodiments of the invention. 
     
    
    
     DETAILED DESCRIPTION 
     The detailed description provided below in connection with the appended drawings is intended as a description of the present examples and is not intended to represent the only forms in which the present examples may be constructed or utilized. The description sets forth the functions of the examples and the sequence of steps for constructing and operating the examples. However, the same or equivalent functions and sequences may be accomplished by different examples. 
       FIG. 1  and the following discussion are intended to provide a brief, general description of a suitable computing environment to implement embodiments of the invention. The operating environment of  FIG. 1  is only one example of a suitable operating environment and is not intended to suggest any limitation as to the scope of use or functionality of the operating environment. Although not required, embodiments of the invention will be described in the general context of “computer readable instructions” being executed by one or more computing devices. Computer readable instructions may be distributed via computer readable media. Computer readable instructions may be implemented as program modules, such as functions, objects, Application Programming Interfaces (APIs), data structures, and the like, that perform particular tasks or implement particular abstract data types. Typically, the functionality of the computer readable instructions may be combined or distributed as desired in various environments. 
       FIG. 1  shows a host  102  connected to mobile device  110  via connection  108 . Host  102  may include any computing device such as a desktop, laptop, and the like. Host  102  may include other computing devices such as a camera, media player, mobile phone, and the like. In one embodiment, mobile device  110  may include a free standing mobile device, such as a mobile phone, a media player, and the like. In another embodiment, mobile device  110  may include a host-dependent mobile device, such as a Universal Serial Bus (USB) Flash Drive, a memory card, a security card, and the like. As used herein, “host-dependent” refers to a mobile device that may not be utilized unless the mobile device is connected to a host. As used herein, “host” refers to a computing device that manages another computing device. The computing device controlled by the “host” is referred to as the “device.” This host/device relationship may also be referred to as a master/slave relationship. 
     Embodiments of the invention may be used with short-lived tasks invoked on demand. In one example, a personal computer (host) may offload complex cryptography computations to a storage device having cryptography dedicated circuitry. In general, cryptography may be performed much faster in hardware than by software instructions executed by a processor. Further, cryptography performed by the dedicated circuitry is usually more secure than software instructions and dedicated circuitry may be required for using some cryptography algorithms (e.g., government use). 
     In another example, a personal computer (host) may offload digital rights management computations or media content watermarking to a connected device (such as a digital camera). The digital cameral may include dedicated circuitry or special routines that may be more efficient than the personal computer in performing these media related tasks. 
     Connection  108  may include a wired or a wireless connection between host  102  at interface  107  and mobile device  110  at interface  116 . In one embodiment, host  102  and mobile device  110  are in close proximity to one another as part of a user&#39;s Personal Area Network (PAN). Examples of connection  108  include USB (wired or wireless), firewire (IEEE 1394), radio frequency (e.g., Bluetooth, Wi-Fi, etc.), infrared, and the like. 
     In one embodiment, a mobile device may be host-capable and serve as a host in some scenarios. For example, a mobile phone may act as mobile device  110  connected to a laptop computer acting as host  102 . In another example, the same mobile phone may act as host  102  connected to a memory card acting as mobile device  110 . In this example, the memory card is a host-dependent mobile device. 
     Host  102  may include a processing unit  104  and memory  106 . Host  102  also includes an interface  107  for inputting/outputting data from host  102 . Host  102  may also include a storage device, such as a Hard Disk Drive or flash memory (not shown). 
     Mobile device  110  may include a controller  112  coupled to storage  114 . Controller  112  may manage the reading/writing of data on storage  114  as well as perform other functions. Storage  114  may include a magnetic disc drive, an optical drive, non-volatile storage, such as flash memory, and the like. 
     From the viewpoint of host  102 , mobile device  110  is considered a transient device. Mobile device  110  may be connected/disconnected from host  102  without warning to host  102 . It will be appreciated that mobile device  110  may be connected/disconnected from host  102  without restarting host  102 . The transient nature of mobile device  110  leads to the dynamic aspect of embodiments herein. Host  102  may take advantage of the processing capabilities of mobile device  110  when the mobile device is present, but when mobile device  110  is disconnected, the host  102  simply notes the unavailability of the device for completing host tasking. Failover handling of situations when mobile device  110  is disconnected from host  102  before an offloaded task is completed is discussed below. Also, in some embodiments, tasks of mobile device  110  may be offloaded to host  102  for completion. Thus, the offloading of tasks between host  102  and mobile device  110  may be bi-directional. 
     Turning to  FIG. 2 , an embodiment of mobile device  110  is shown. Mobile device  110  may include a smart storage device such as a USB Flash Device (UFD), a memory card, and the like. In one embodiment, a smart storage device is host-dependent for operability. Mobile device  110  may also include free-standing devices such as media players, mobile phones, Personal Digital Assistants (PDAs), and the like. 
     Controller  112  may include a processing unit  206  and non-volatile storage (NVS)  210 . Processing unit  206  may include a general processor, such as a 32-bit Reduced Instruction Set Computing (RISC) processor. While a single processing unit  206  is shown, embodiments of mobile device  110  may include multiple processing units such as multiple processors, multiple cores, and the like. 
     In one embodiment, NVS  210  has stored firmware  212  that may be executed by processing unit  206 . Firmware  212  may include an operating system (such as a Real-Time Operating System (RTOS)), one or more applications, and the like, for mobile device  110 . Firmware  212  may also include instructions for executing embodiments of the invention. 
     In the embodiment of  FIG. 2 , controller  112  includes dedicated circuitry  208 . Dedicated circuitry  208  includes hardware that may perform specialized operations. Examples of dedicated circuitry  208  include an Application-Specific Integrated Circuit (ASIC), a Field Programmable Logic Array (FPLA), Field Programmable Gate Array (FPGA), and the like. Functionality performed by dedicated circuitry  208  may include cryptography, digital signal processing, digital rights management, and the like. Embodiments herein enable host  102  to utilize the functionality of dedicated circuitry  208  for more efficiently completing host workflows. 
     Turning to  FIG. 3 , a flowchart  300  shows the logic and operations of offloading tasks from a host to a mobile device in accordance with an embodiment of the invention. Flowchart  800  of  FIG. 8  (discussed below) shows embodiments where device tasks are offloaded to the host for the host to complete. It will be understood that at least some of the logic of flowcharts  300  and  800  may occur at the same time. In other words, in some instances, host  102  may offload tasks to mobile device  110  while at the same time mobile device  110  offloads tasks to host  102 . Thus, the offloading of tasks between host  102  and mobile device  110  may be bi-directional. 
     In one embodiment, the logic of flowchart  300  occurs during a session when the mobile device is connected to the host. A single session begins when the mobile device is connected to the host and ends when the mobile device is disconnected from the host. From the perspective of the host, the mobile device is transient and the presence of the mobile device is unpredictable. Further, the length of any session with the mobile device is unpredictable and the time between sessions is also unpredictable. As discussed below, embodiments of the invention cope with the transient nature of the mobile device when offloading host tasks. 
     Starting in block  302 , a mobile device connects to a host. The connection may be via wired connection or a wireless connection. In one embodiment of the invention, the host does not need prior knowledge of the mobile device or task offloading in order to implement embodiments of the invention. This may be the first time the host has seen the mobile device. The mobile device may provide the host the means for offloading tasks to the mobile device. In one embodiment, setting up the connection may include establishing a secured communication session between the host and the mobile device. 
     In one example, the mobile device may be used with a public host, such a public computer at a kiosk. For example, a user wishes to use a public computer at an airport to check email on the user&#39;s corporate network. However, the connection requires a certain cryptography algorithm that is not supported by the public computer or may take too long to execute by the limited processing capabilities of the public computer. The user may connect their USB Flash Drive (UFD) (that contains dedicated cryptography circuitry) to the public computer. With embodiments herein, the public computer may use the dedicated cryptography circuit of the UFD to connect to the user&#39;s corporate network. In this example, all footprints of the session with the public host may be removed when the session ends. 
     Proceeding to block  304 , the mobile device exposes its functions to the host. In one embodiment, the mobile device functions are exposed as interfaces that may be utilized by the host. For example, the mobile device may expose an ENCRYPT interface that will encrypt a block of data for the host. Embodiments of exposing device functions are discussed below in connection with  FIGS. 4-7 . 
     Continuing to block  306 , the mobile device uploads host policies to the host for offloading host tasks. In one embodiment, this may be the first connection between the host and the mobile device and the host may not have stored host policies. Also, by providing the host with default host policies, prior knowledge of task offloading by the host is not necessary to carry out embodiments of the invention. 
     Continuing to block  308 , the host applies host policies. In one embodiment, the host has received polices from the mobile device as described in block  306 . In another embodiment, the host may have already stored host policies or have stored host policies from a previous session with the mobile device. In yet another embodiment, the host may acquire (and then merge with any policies already stored on the host) host policies from a central server in a managed network. For example, a managed network may want to push the same policy to all (or groupings of) managed hosts. Alternatively, policy stored at a central server may be tailored for each particular host. Also, the ability to update the policy at a central server location would ease system administration of the managed network. 
     As used herein, a “host task” refers to a computational task to be performed by the host. When a mobile device is connected, the host policies determine whether execution of a host task may be performed by a function exposed by the mobile device. In general, one or more device functions may be used to complete a host task. 
     For example, a host task may be to encrypt a text document of 500 KB using encryption algorithm A. The mobile device has exposed a function that will encrypt 100 KB blocks of data using encryption algorithm A with dedicated circuitry. The host may complete the host tasking of encrypting the text document by calling the device function 5 times to complete the host tasking. 
     In one embodiment, multiple functions may be called in the form of a batch using a script language executable by the mobile device. The mobile device would have knowledge of the batch language and be able to execute the batch language for executing multiple functions. 
     Host polices control offloading of tasks to the mobile device. For example, a host policy may be “if a device with encryption algorithm A is present, then offload algorithm A encryption tasks to the device.” The host polices may be modifiable by a user or a system administrator. In one embodiment, host policies may be associated with an administrative polices, such as security. For example, the host may not offload tasks until the mobile device can be authenticated. 
     In another embodiment, host policies may be associated with host performance issues. For example, tasks will be offloaded where a significant increase in performance is expected (e.g., above some threshold). In another example, a task that is relied upon for a lengthy series of follow-on tasks may not necessarily be offloaded. This is because of the expected transient nature of the mobile device. If the mobile device is disconnected while the mobile device is still performing the task, then the host will not receive the results of the offloaded task. In this instance, the host may have to perform the task itself from the beginning, and thus, waste time. 
     In another embodiment, host policies may monitor the health of the mobile device. The host may monitor performance factors of the mobile device such as processor load, available memory space, and the like. Another mobile device health indicator may include execution time of an offloaded task. Host policies may suspend host task offloading until mobile device health improves. 
     Proceeding to block  310  of flowchart  300 , the host offloads a task to the mobile device by calling one or more exposed mobile device functions as described in block  304 . As discussed further below, in one embodiment, these functions may be exposed as interfaces, such as APIs, to applications and the operating system. 
     In an alternative embodiment, the host may offload a task by downloading an executable image or an intermediate language to the mobile device. For example, the offloaded task may include an executable routine written in a platform neutral language. The mobile device may advertise support for the platform neutral language during the connection handshake. The device driver on the host may download the executable routine to the mobile device when needed (i.e., on the fly). The return of the completed task may also be handled by the device driver. In another example, the intermediate language may include an interpreted language that may be run using an interpreter on the host or a compatible interpreter on the mobile device. 
     While flowchart  300  shows an embodiment of offloading one task from the host, it will be appreciated that more than one task may be offloaded to the mobile device at one time. It will also be understood that one or more tasks may be offloaded at different times to the mobile device without regards to when results of the tasks are returned to the host. These embodiments (and others) may be implemented through the host polices. For example, task A may be offloaded at time T 1  and task B offloaded at time T 2 . The execution of tasks A and B may occur without regard to the other. Also, tasks A and B may not even be associated with each other. For example, task A may be related to encrypting data for storage on the mobile device and task B may be related to signal processing of a Wi-Fi signal by the DSP of the mobile device. 
     Continuing to block  312 , the mobile device performs the function in compliance with mobile device policies. A mobile device&#39;s policies may be related to security, administrative items, and the like. For example, a mobile device may need to authenticate the host before performing any offloaded task requests. In another example, a UFD may include crypto hardware for use by a government agency. The host may request use of the crypto hardware for encrypting an email being sent from a user&#39;s personal non-government email (e.g., a Hotmail account). The mobile device may have a policy of only encrypting email being sent from (or to) a government email address because the encryption algorithm is classified. Because of this policy, the mobile device may refuse to perform the encryption for the user&#39;s personal email. In one embodiment, device policies may be updated when connected to a host, such as an administrative host. The updated device policies may then be enforced by the device in future task offloading from the currently connected host or other hosts. 
     Mobile device polices may also indicate if particular mobile device activities take precedent over host task offloading. For example, if the device is a mobile phone, when a call arrives for the mobile phone, any DSP activity for the host is suspended until the phone call for the mobile phone is completed. 
     Continuing to block  314 , the host receives the results of the function from the mobile device. The results may be in any appropriate form such as Boolean, integer, floating-point integer, string, and the like. For example, the mobile device may expose an encryption function with two parameters: 100 KB data block to encrypt and a key. The mobile device performs the encryption and returns an encrypted data block to the host. The host may then use the encrypted block as desired (e.g., save on local storage, send to network storage, send as email, etc.). 
     Proceeding to decision block  316 , the logic of flowchart  300  determines if the mobile device has been disconnected. In one embodiment, the logic of flowchart  300  is alerted by the host OS when the mobile device is removed using well known methods. If the answer to decision block  316  is no, then the logic returns to block  308  to offload another task to the mobile device from the host. Flowchart  300  may repeatedly loop through blocks  308 - 316  offloading tasks from the host to the mobile device until the mobile device is disconnected from the host. 
     If the answer to decision block  316  is yes, then the logic continues to decision block  318 . At decision block  318 , the logic determines if the host has received results from all called functions. Since the mobile device is transient in nature, the mobile device may be removed at anytime while the host is running. Thus, the mobile device may be removed when the host is still waiting for results of an offloaded task. 
     If the answer to decision block  318  is yes, then flowchart  300  ends. If the answer to decision block  318  is no, then the logic proceeds to block  320  for performing failover handling by the host. In one embodiment, the host inventories the task(s) that did not complete before the mobile device was disconnected. The function(s) associated with these incomplete task(s) will then be completed by the host. These tasks may be re-started and performed by the host or may be offloaded to another mobile device that is connected to the host and supports task offloading as described herein. After block  320 , flowchart  300  ends. 
     Turning to  FIG. 4 , an embodiment of exposing functions by the mobile device to the host is shown. In  FIG. 4 , a host  402  is connected to a mobile device  404 . In order to expose its available functions, mobile device  404  sends a software module  406  (executable on the host) stored on mobile device  404  to host  402 . 
     In one embodiment, software module  406  includes one or more interfaces, such as APIs, that may be used by host  402 . In one embodiment, the APIs may be exposed to host  402  as a library of Component Object Model (COM) objects for use by applications and/or an OS operating on host  402 . The use of the mobile device for executing the APIs may be transparent to the applications and/or OS. The APIs would divert computations to the mobile device. In other embodiments, software module  406  may include language neutral objects, such as Java® objects, Common Language Runtime (CLR) objects, and the like. 
     In one embodiment, when mobile device  404  is disconnected from host  402 , the APIs of software module  406  are marked as unavailable from host  402 . In this way, software executing on host  402  will not attempt to call APIs that are no longer available since mobile device  404  has been disconnected. In alternative embodiments, uploaded software module  406  is purged from host  402  after mobile device  404  is disconnected. 
     In one embodiment, host  402  may authenticate software module  406 . Such authentication techniques may include use of a certificate, a signature, and the like. In other embodiments, software module  406  may need to be digitally signed to be recognized and loaded in accordance with host policies. 
       FIG. 5  shows one embodiment of authenticating software module  406 . In  FIG. 5 , host  402  may contact an update manager  504  via network  502 . Update manager  504  may authenticate software module  406  and may offer updates to software module  406  to host  402 . In one embodiment, updates to software module  406  received by host  402  may also be used to update software module  406  stored on mobile device  404 . In one embodiment, the update manager  504  may include Microsoft Windows® Update. 
     Turning to  FIG. 6 , another embodiment of exposing functions by the mobile device is shown.  FIG. 6  shows mobile device  404  connected to host  402 . Host  402  includes an application  602  supported by OS  604 . OS  604  includes a device driver  606  for communicating with mobile device  404 . Mobile device  404  may report to driver  606  that the mobile device  404  has available functions. The functions may be expressed using a self-describing language. Device driver  606  is aware of the self-describing language. For example, the concept of Web Services Description Language (WSDL) may be applied to exposing functions to driver  606  in the host driver stack. NVS  608  may have stored a set of interfaces  610  (that correspond to the mobile device functions) that are provided to driver  606  using the self-describing language. Driver  606  may use an interface to request mobile device  404  perform the corresponding function. In this example, specific interfaces supported by the mobile device do not need to by known by the host OS or host applications in advance (i.e., prior to connection of the mobile device). These interfaces may be discovered upon mobile device connection and then bind to the host. This example differs from other implementations in which the host would either have to have pre-loaded libraries that are compatible with the mobile device or upload a whole library on connection to the mobile device (such as discussed in  FIGS. 4-5 ). 
     In one embodiment, host  402  and mobile device  404  may extend a well known protocol for exposing and calling the device functions. For example, in the case of a storage device, a Small Computer System Interface (SCSI) protocol may be extended for embodiments herein. The SCSI protocol may be extended to enable the mobile device to report the function descriptors to the host using a self-describing language. The SCSI host driver may be extended to understand these function descriptors. The extended SCSI host driver would use the self-describing language to expose these capabilities to the host OS and host applications so they can utilize the device functions. The extended SCSI host driver would report the connected mobile device to OS  604  and expose the available functions to OS  604  and application  602 . When a function is requested by OS  604  or application  602 , then the SCSI host driver may manage the calling of the function on the mobile device. 
     An embodiment of an array of descriptors  700  that may be provided by mobile device  404  is shown in  FIG. 7 . Array  700  includes the function name  702 , input argument(s)  704 , and return value(s)  706 . For example, function ENCRYPT — 1 encrypts a block of data from 0 to 100 KB using a provided 128-bit key. The function returns the data in encrypted form in a 0-100 KB data block. 
     It will be appreciated that in the embodiments of  FIGS. 6 and 7 , execution code for the functions is not being inserted into the host system. The code for the functions is kept on the mobile device and executed on the mobile device. Also, the calling and return of a function is kept at the driver level of host  402 . 
     It will also be appreciated that the host device driver does not have to be updated to utilize the functions of the mobile device. The extended host device driver may query the mobile device for its functions. Since the mobile device functions are expressed in a self-describing language, the extended host device driver does not need prior knowledge of the mobile device functions to utilize those mobile device functions. This self-describing feature may differentiate embodiments of the invention from today&#39;s mobile devices that require the host to be loaded with a new driver in order to utilize the mobile device. 
     Embodiments of the invention are also distinguishable from Plug-and-Play (PnP). In PnP, the host OS must find a matching device driver in local storage or in a network storage in order to fully utilize the mobile device. In embodiments herein, the mobile device provides the host with the ability to utilize the mobile device&#39;s functionality. The host is not required to provide specialized device drivers for the mobile device functions. 
     Turning to  FIG. 8 , a flowchart  800  shows the logic and operations of offloading a task from a mobile device to a host in accordance with an embodiment of the invention. Similarly as with flowchart  300 , flowchart  800  shows the offloading of a single task, but one skilled in the art having the benefit of this description will appreciate that more than one task may be offloaded at a time from the mobile device to the host. Also, multiple mobile device tasks are not necessarily offloaded at the same time. Further, multiple device tasks may be executed by the host using batch programming. 
     Starting in block  802 , the mobile device connects to the host. Continuing to block  804 , the mobile device applies device polices. The mobile device may include modifiable policies about which tasks may be offloaded and when tasks may be offloaded. For example, device policies may require the mobile device to authenticate the host before offloading any tasks to the host. In another example, the device policies may allow offloading device tasks when the host meets particular performance thresholds, such as host processor speed. 
     Proceeding to block  806 , the mobile device offloads the device task to the host. In one embodiment, the mobile device loads the host memory with executable code for execution on the host processor. A host executable image may be stored on the mobile device. Any data the host is to operate on may also be offloaded to the host. 
     In one embodiment, if the offloaded task is a continuation of a previously offloaded device task, then the offloaded device task may continue from a position indicated by saved state information (discussed further below). 
     Next, in block  808 , the host performs the device task. For example, the mobile device may have stored numerous music files that need to be indexed. While the mobile device may have the ability to index the music files itself, the mobile device may utilize the processing power of the host if the host has a faster processor. In this example, the mobile device may include a media player, a mobile phone with media player capabilities, and the like. In another example, the mobile device may use the host for transcoding of media content stored on the mobile device. Normally, transcoding (i.e., reformatting media content for use with various applications and platforms) is a computationally expensive operation. With embodiments herein, the mobile device may use the computing power of the host for transcoding when connected to the host. 
     In block  810 , the mobile device may periodically store the state of the device task being performed by the host. Since the mobile device is of a transient nature, the mobile device saves the task state so that the task may be offloaded and continued at a subsequent session with the host (or another host). In an alternative embodiment, the mobile device may be able to complete the task without a host by continuing from the saved task state. 
     Proceeding to block  812 , the mobile device receives the results of the task from the host. In decision block  814 , the logic determines if the mobile device has been disconnected. If the answer to decision block  814  is no, then the logic returns to block  804  to offload another task. If the answer to decision block  814  is yes, then the logic continues to decision block  816 . 
     At decision block  816 , the logic determines if the mobile device received the results of all offloaded tasks. If the answer to decision block  816  is yes, then flowchart  800  ends. If the answer to decision block  816  is no, then the logic continues to block  818  where the mobile device performs failover handling. In one embodiment, the mobile device may preserve the saved state of the task so that the next time the mobile device connects to a host, the mobile device may offload the task for completion. In another embodiment, the mobile device, if free-standing, may finish the task itself by continuing from the saved task state. In yet another embodiment, the mobile device may ignore the saved task state. In this embodiment, the task may be restarted from the beginning the next time the mobile device is connected to a host. 
     Embodiments of the invention provide for offloading tasks between a host and a mobile device. In one embodiment, when connected to a host, a mobile device exposes functions to the host that the host may utilize. In this way, the host may utilize the processing capability and/or specialized hardware of the mobile device for more efficiently completing host workflows. Similarly, the mobile device may offload tasks to the host for execution by the host. 
       FIG. 9  shows an example of a computing device  900  for implementing one or more embodiments of the invention. For example, host  102  or mobile device  110  may be implementations of computing device  900 . In one configuration, computing device  900  includes at least one processing unit  902  and memory  904 . Depending on the exact configuration and type of computing device, memory  904  may be volatile (such as RAM), non-volatile (such as ROM, flash memory, etc.) or some combination of the two. This configuration is illustrated in  FIG. 9  by dashed line  906 . 
     In other embodiments, device  900  may include additional features and/or functionality. For example, device  900  may also include additional storage (e.g., removable and/or non-removable) including, but not limited to, magnetic storage, optical storage, and the like. Such additional storage is illustrated in  FIG. 9  by storage  908 . In one embodiment, computer readable instructions to implement embodiments of the invention may be stored in storage  908 . Storage  908  may also store other computer readable instructions to implement an operating system, an application program, and the like. 
     The term “computer readable media” as used herein includes computer storage media. Computer storage media includes volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions or other data. Memory  904  and storage  908  are examples of computer storage media. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, Digital Versatile Disks (DVDs) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by device  900 . Any such computer storage media may be part of device  900 . 
     Device  900  may also include communication connection(s)  912  that allow device  900  to communicate with other devices. Communication connection(s)  912  may include, but is not limited to, a modem, a Network Interface Card (NIC), or other interfaces for connecting computing device  900  to other computing devices. Communication connection(s)  912  may include a wired connection or a wireless connection. Communication connection(s)  912  may transmit and/or receive communication media. 
     The term “computer readable media” may include communication media. Communication media typically embodies computer readable instructions or other data in a “modulated data signal” such as a carrier wave or other transport mechanism and includes any information delivery media. The term “modulated data signal” means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, radio frequency, infrared, Near Field Communication (NFC), and other wireless media. 
     Device  900  may include input device(s)  914  such as keyboard, mouse, pen, voice input device, touch input device, infra-red cameras, video input devices, and/or any other input device. Output device(s)  916  such as one or more displays, speakers, printers, and/or any other output device may also be included in device  900 . Input device(s)  914  and output device(s)  916  may be connected to device  900  via a wired connection, wireless connection, or any combination thereof. In one embodiment, an input device or an output device from another computing device may be used as input device(s)  914  or output device(s)  916  for computing device  900 . 
     Components of computing device  900  may be connected by various interconnects, such as a bus. Such interconnects may include a Peripheral Component Interconnect (PCI), such as PCI Express, a Universal Serial Bus (USB), firewire (IEEE 1394), an optical bus structure, and the like. In another embodiment, components of computing device  900  may be interconnected by a network. For example, memory  904  may be comprised of multiple physical memory units located in different physical locations interconnected by a network. 
     Those skilled in the art will realize that storage devices utilized to store computer readable instructions may be distributed across a network. For example, a computing device  930  accessible via network  920  may store computer readable instructions to implement one or more embodiments of the invention. Computing device  900  may access computing device  930  and download a part or all of the computer readable instructions for execution. Alternatively, computing device  900  may download pieces of the computer readable instructions, as needed, or some instructions may be executed at computing device  900  and some at computing device  930 . Those skilled in the art will also realize that all or a portion of the computer readable instructions may be carried out by a dedicated circuit, such as a Digital Signal Processor (DSP), programmable logic array, and the like. 
     Various operations of embodiments of the present invention are described herein. In one embodiment, one or more of the operations described may constitute computer readable instructions stored on one or more computer readable media, which if executed by a computing device, will cause the computing device to perform the operations described. The order in which some or all of the operations are described should not be construed as to imply that these operations are necessarily order dependent. Alternative ordering will be appreciated by one skilled in the art having the benefit of this description. Further, it will be understood that not all operations are necessarily present in each embodiment of the invention. 
     The above description of embodiments of the invention, including what is described in the Abstract, is not intended to be exhaustive or to limit the embodiments to the precise forms disclosed. While specific embodiments and examples of the invention are described herein for illustrative purposes, various equivalent modifications are possible, as those skilled in the relevant art will recognize in light of the above detailed description. The terms used in the following claims should not be construed to limit the invention to the specific embodiments disclosed in the specification. Rather, the following claims are to be construed in accordance with established doctrines of claim interpretation.