VEHICLE AND PORTABLE DEVICE COMMUNICATION

A portable computing device includes a processor and a memory, the memory storing instructions executable by the processor to initiate communication between the portable computing device and a vehicle computer via a first access address provided by the vehicle computer, then, based on at least one of (1) a user input to the portable computing device, or (2) a change of an output of the portable computing device, obtain from the vehicle computer a second access address for the vehicle computer, and provide a command to the vehicle computer to actuate one or more vehicle components via the second access address.

BACKGROUND

Portable devices, such as mobile phones and wearable devices, can communicate with vehicles. The portable devices can transmit data and/or messages to the vehicles, and the vehicles can transmit data and/or messages to the portable devices. These communications can occur over a wireless network. Such networks typically have dedicated bandwidth for communications.

DETAILED DESCRIPTION

A system includes a portable computing device including a processor and a memory, the memory storing instructions executable by the processor to initiate communication between the portable computing device and a vehicle computer via a first access address provided by the vehicle computer, then, based on at least one of (1) a user input to the portable computing device, or (2) a change of an output of the portable computing device, obtain from the vehicle computer a second access address for the vehicle computer, and provide a command to the vehicle computer to actuate one or more vehicle components via the second access address.

The instructions can further include instructions to input an encryption key to an address generator program to obtain the second access address, the encryption key being a numeric key stored in both the portable computing device and the vehicle computer.

The instructions can further include instructions to generate the encryption key upon initiating communication between the portable computing device and the vehicle computer.

The instructions can further include instructions to generate the encryption key upon identifying the user input to the portable computing device or the change of the output of the portable computing device.

The instructions can further include instructions to send the generated encryption key to the vehicle computer via the first access address.

The instructions can further include instructions to receive the encryption key from the vehicle computer via the first access address.

The address generator program can be a Resolvable Private Address program, and the encryption key can be an Identity Resolving Key.

The instructions can further include instructions to obtain the second access address upon determining that an elapsed time from generation of the first access address exceeds a time threshold.

The instructions can further include instructions to cease communication with the vehicle computer upon identifying the user input to the portable computing device or the change of the output of the portable computing device, request the second access address from the vehicle computer, obtain the second access address, and reestablish communication with the vehicle computer via the second access address.

The instructions can further include instructions to identify the user input on the portable computing device as an input to actuate one or more vehicle components and to provide a command to the vehicle computer based on the user input via the first access address.

The instructions can further include instructions to generate the second access address when the identified user input is an input other than the input to actuate one or more vehicle components.

The user input to the portable computing device can be a haptic input to an icon on a display of the portable computing device.

The change of the output of the portable computing device can be a transition to a darkened power-saving display.

The system can further include the vehicle computer, wherein the vehicle computer is programmed to generate the second access address upon detecting the portable computing device cease communication with the vehicle computer and then receiving a request to reestablish communication with the vehicle computer.

A method includes initiating communication between the portable computing device and a vehicle computer via a first access address provided by the vehicle computer, then, based on at least one of (1) a user input to the portable computing device, or (2) a change of an output of the portable computing device, obtaining from the vehicle computer a second access address for the vehicle computer, and providing a command to the vehicle computer to actuate one or more vehicle components via the second access address.

The method can further include inputting an encryption key to an address generator program to obtain the second access address, the encryption key being a numeric key stored in both the portable computing device and the vehicle computer.

The method can further include generating the encryption key upon initiating communication between the portable computing device and the vehicle computer.

The method can further include generating the encryption key upon identifying the user input to the portable computing device or the change of the output of the portable computing device.

The method can further include sending the generated encryption key to the vehicle computer via the first access address.

The method can further include receiving the encryption key from the vehicle computer via the first access address.

The method can further include obtaining the second access address upon determining that an elapsed time from generation of the first access address exceeds a time threshold.

The method can further include ceasing communication with the vehicle computer upon identifying the user input to the portable computing device or the change of the output of the portable computing device, requesting the second access address from the vehicle computer, obtaining the second access address, and reestablishing communication with the vehicle computer via the second access address.

The method can further include identifying the user input on the portable computing device as an input to actuate one or more vehicle components and providing a command to the vehicle computer based on the user input via the first access address.

The method can further include generating the second access address when the identified user input is an input other than the input to actuate one or more vehicle components.

The method can further include generating the second access address in the vehicle computer upon detecting the portable computing device cease communication with the vehicle computer and then receiving a request to reestablish communication with the vehicle computer.

A system includes a portable computing device and a vehicle computer including a processor and a memory, the memory storing instructions executable by the processor to initiate communication with the portable computing device via a first access address, receive a request from the portable computing device to generate a second access address, reestablish communication between the portable computing device via the second access address, and receive a command from the portable computing device to actuate one or more vehicle components via the second access address.

The instructions can further include instructions to generate the second access address upon detecting the portable computing device cease communication with the vehicle computer and then receiving a request from the portable computing device to reestablish communication with the vehicle computer.

The instructions can further include instructions to input an encryption key to an address generator program to generate the second access address, the encryption key being a numeric key stored in both the portable computing device and the vehicle computer.

The instructions can further include instructions to generate the encryption key upon initiating communication between the portable computing device and the vehicle computer.

The instructions can further include instructions to generate the second access address upon determining that an elapsed time from generation of the first access address exceeds a time threshold.

Further disclosed is a computing device programmed to execute any of the above method steps. Yet further disclosed is a vehicle comprising the computing device. Yet further disclosed is a computer program product, comprising a computer readable medium storing instructions executable by a computer processor, to execute any of the above method steps.

Communications between a portable computing device and a vehicle computer occur over a communications protocol specified between the portable computing device and the vehicle computer. One such protocol is Bluetooth® Low Energy (BLE). Communications over BLE can be secured by changing an access address of communication between the portable device and the vehicle computer. Changing the access address requires the portable device to perform a plurality of computations, which consumes energy from a battery of the portable device. Frequent changes to the access address can drain the battery of the portable device.

As explained herein, changing the access address upon detecting a specified change in operation of an application executing on the portable device advantageously provides security for communications between the portable device and the vehicle computer while reducing the amount of energy consumed to change the access address. That is, in examples of changes to application operation discussed further below, when a user provides input to the portable device or a program on the portable device changes an output of the portable device, the portable device can update the access address. By changing an access address only upon changes in application operation, the portable device reduces the total number of changes to the access address during communication with the vehicle computer, while still changing the access address often enough to secure communications with the vehicle computer. Thus, battery consumption of the portable device is reduced.

FIG. 1illustrates an example system100for operating a vehicle105. A computer110in the vehicle105is programmed to receive collected data from one or more sensors115. For example, vehicle105data may include a location of the vehicle105, data about an environment around a vehicle, data about an object outside the vehicle such as another vehicle, etc. A vehicle105location is typically provided in a conventional form, e.g., geo-coordinates such as latitude and longitude coordinates obtained via a navigation system that uses the Global Positioning System (GPS). Further examples of data can include measurements of vehicle105systems and components, e.g., a vehicle105velocity, a vehicle105trajectory, etc.

The computer110is generally programmed for communications on a vehicle105network, e.g., including a conventional vehicle105communications bus such as a CAN bus, LIN bus, etc., and or other wired and/or wireless technologies, e.g., Ethernet, WIFI, etc. Via the network, bus, and/or other wired or wireless mechanisms (e.g., a wired or wireless local area network in the vehicle105), the computer110may transmit messages to various devices in a vehicle105and/or receive messages from the various devices, e.g., controllers, actuators, sensors, etc., including sensors115. Alternatively or additionally, in cases where the computer110actually comprises multiple devices, the vehicle network may be used for communications between devices represented as the computer110in this disclosure. For example, the computer110can be a generic computer with a processor and memory as described above and/or may include a dedicated electronic circuit including an ASIC that is manufactured for a particular operation, e.g., an ASIC for processing sensor data and/or communicating the sensor data. In another example, computer110may include an FPGA (Field-Programmable Gate Array) which is an integrated circuit manufactured to be configurable by a user. Typically, a hardware description language such as VHDL (Very High Speed Integrated Circuit Hardware Description Language) is used in electronic design automation to describe digital and mixed-signal systems such as FPGA and ASIC. For example, an ASIC is manufactured based on VHDL programming provided pre-manufacturing, whereas logical components inside an FPGA may be configured based on VHDL programming, e.g. stored in a memory electrically connected to the FPGA circuit. In some examples, a combination of processor(s), ASIC(s), and/or FPGA circuits may be included in computer110.

In addition, the computer110may be programmed for communicating with the network125, which, as described below, may include various wired and/or wireless networking technologies, e.g., cellular, Bluetooth®, Bluetooth® Low Energy (BLE), wired and/or wireless packet networks, etc.

The memory can be of any type, e.g., hard disk drives, solid state drives, servers, or any volatile or non-volatile media. The memory can store the collected data sent from the sensors115. The memory can be a separate device from the computer110, and the computer110can retrieve information stored by the memory via a network in the vehicle105, e.g., over a CAN bus, a wireless network, etc. Alternatively or additionally, the memory can be part of the computer110, e.g., as a memory of the computer110.

Sensors115can include a variety of devices. For example, various controllers in a vehicle105may operate as sensors115to provide data via the vehicle105network or bus, e.g., data relating to vehicle speed, acceleration, location, subsystem and/or component status, etc. Further, other sensors115could include cameras, motion detectors, etc., i.e., sensors115to provide data for evaluating a position of a component, evaluating a slope of a roadway, etc. The sensors115could, without limitation, also include short range radar, long range radar, LIDAR, and/or ultrasonic transducers.

Collected data can include a variety of data collected in a vehicle105. Examples of collected data are provided above, and moreover, data are generally collected using one or more sensors115, and may additionally include data calculated therefrom in the computer110, and/or at the server130. In general, collected data may include any data that may be gathered by the sensors115and/or computed from such data.

The vehicle105can include a plurality of vehicle components120. In this context, each vehicle component120includes one or more hardware components adapted to perform a mechanical function or operation—such as moving the vehicle105, slowing or stopping the vehicle105, steering the vehicle105, etc. Non-limiting examples of components120include a propulsion component (that includes, e.g., an internal combustion engine and/or an electric motor, etc.), a transmission component, a steering component (e.g., that may include one or more of a steering wheel, a steering rack, etc.), a brake component, a park assist component, an adaptive cruise control component, an adaptive steering component, a movable seat, and the like. Components120can include computing devices, e.g., electronic control units (ECUs) or the like and/or computing devices such as described above with respect to the computer110, and that likewise communicate via a vehicle105network.

The system100can further include a network125connected to a server130. The computer110can further be programmed to communicate with one or more remote sites such as the server130, via the network125, such remote site possibly including a processor and a memory. The network125represents one or more mechanisms by which a vehicle computer110may communicate with a remote server130. Accordingly, the network125can be one or more of various wired or wireless communication mechanisms, including any desired combination of wired (e.g., cable and fiber) and/or wireless (e.g., cellular, wireless, satellite, microwave, and radio frequency) communication mechanisms and any desired network topology (or topologies when multiple communication mechanisms are utilized). Exemplary communication networks include wireless communication networks (e.g., using Bluetooth®, Bluetooth® Low Energy (BLE), IEEE 802.11, vehicle-to-vehicle (V2V) such as Dedicated Short Range Communications (DSRC), etc.), local area networks (LAN) and/or wide area networks (WAN), including the Internet, providing data communication services.

The system100includes a portable device135. The portable device135may be any one of a variety of devices, such as computing devices including a processor and a memory, that have communication capabilities to communicate over the network125. For example, the portable device135may be a wearable device, e.g. a watch or a smart watch, a smartphone, a tablet, a personal digital assistant, a watch-phone pairing, a vibrating apparatus, etc. that includes capabilities for wireless communications using IEEE 802.11, Bluetooth®, UWB, NFC, and/or cellular communications protocols. Further, the portable device135may use such communications capabilities to communicate directly with a vehicle computer110, e.g., using Bluetooth®.

The portable device135can communicate with the computer110via an access address. An “access address” is a set of numeric values that the portable device135and the computer110append to each communication to confirm that the communications are intended for the portable device135and the computer110. The access address can be a previously generated set of numeric values stored in a memory of the computer110and broadcast to the portable device135. That is, the computer110and the portable device135can, upon receiving a packet of data including the access address, accept the packet knowing that the packet originated from the computer110or the portable device135. The access address can be generated upon initiating communication between the computer110and the portable device135, i.e., upon “pairing” the computer110and the portable device135via Bluetooth® Low Energy. When the computer110and the portable device135have previously initiated communication (i.e., when the computer110and the portable device135have previously been paired), the access address can be a previously generated access address generated upon the first communication between the computer110and the portable device135.

FIG. 2is a view of an example portable device135communicating with a vehicle computer110. As described above, the portable device135and the vehicle computer110use an access address stored in the vehicle computer110and broadcast by the vehicle computer110to transmit messages via, e.g., Bluetooth® Low Energy. The access address may be intercepted by a third party eavesdropping device, e.g., in what is sometimes referred to as a man-in-the-middle attack. Thus, to prevent a third party from sending messages to the computer110and the portable device135with the access address, the computer110and the portable device135can change the access address periodically. That is, upon changing the access address, the computer110and the portable device135can ignore messages with the previous access address and only accept messages with the new access address.

The portable device135can initiate communication between the portable device135and the computer110via a first access address provided by the computer110. Alternatively, the computer110can initiate communication with the portable computing device135via the first access address. The first access address can be a default access address that the computer110broadcasts to nearby devices such as the portable device135. That is, the computer110can initially communicate with the portable device135via the first access address.

The portable device135can provide a command to the vehicle computer110. For example, the portable device135can provide a command to the vehicle computer110to actuate one or more vehicle components120, e.g., to actuate a lock on a door, to activate a propulsion, to actuate a climate controller, etc. A user can provide input to the portable device135, e.g., to a touchscreen of the portable device135. Based on the input, the portable device135can provide the command to the vehicle computer110. The portable device135can provide the command via the access address. Thus, the user can actuate the vehicle components120remotely from the vehicle105.

The computer110and/or the portable device135can change the access address used to communicate between the computer110and the portable device135. That is, to prevent eavesdroppers from intercepting communications between the computer110and the portable device135, at least one of the computer110or the portable device135can request to change the access address. Frequently changing the access address reduces the likelihood that an eavesdropper would have a current access address. Changing the access address can consume energy from a battery of the portable device135, so reducing the total number of changes to the access address during communication with the vehicle computer110can reduce power consumption and extend and/or preserve the battery life of the portable device135.

The portable device135can determine to change the access address based on a change in operation of an application on the portable device135. A “change” in operation of the application is a new input or output from a current input or output of the portable device135. The change in operation can include an input to the portable device, the input being a physical input from a user to a display of the portable device135. That is, the user can provide a physical input to an icon on the display of the portable device135, and the portable device can determine to change the access address upon receiving the input to the display of the portable device135. The physical input can include, e.g., input to an icon to provide a command to actuate one or more components120, input to an icon to close a current application, input to an icon to open another application, etc.

The change in operation can include a change of output of the portable device135, e.g., a change to one or more visible items on a display of the portable device135. That is, the output to the display of the portable device135can change based on whether the portable device135has received input, and the portable device135can determine to change the access address when one or more visible items on the display of the portable device135change. For example, the change in the display of the portable device135can be a transition of the display to a darkened power-saving display when no input has been provided to the display for an elapsed time exceeding a time threshold. In another example, the change in the display of the portable device135can be a transition to a default set of icons on the display, i.e., a “home screen.” That is, the “change in operation” of the application can include a user input to the display to the portable device135and/or a transition of the display to a darkened power-saving display.

After detecting the change in the application, the portable device135can obtain a second access address. The portable device135can obtain the second access address from the vehicle computer110. Alternatively, the portable device135can generate the second access address and send a message to the vehicle computer110requesting to communicate via the second access address. Alternatively or additionally, the portable device135can obtain the second access address upon determining that an elapsed time from generation of the first access address exceeds a time threshold. That is, the portable device135can obtain the second access address and predetermine intervals of time determined by a manufacturer and/or a security program to reduce the likelihood that an eavesdropper would have a current access address.

The user can provide input to the portable device135to actuate one or more vehicle components120, as described above, and as may be known via various “mobile apps,” i.e., applications that run on smartphones or the like to provide access to and/or control of a vehicle. For example, as shown inFIG. 2, the portable device135can display a plurality of icons to which the user can provide input. The user can provide input to one of the icons to, e.g., lock a door of the vehicle105, unlock a door of the vehicle105, remotely start a propulsion of the vehicle105, etc. The user input can be a haptic input to an icon on the display of the portable computing device135, e.g., a touch, a swipe, a pinch, etc. The portable device135and/or the vehicle computer110can generate the second access address upon identifying user input that is an input other than input to actuate the vehicle components120. That is, while the user is providing input to actuate the components120, the computer110and the portable device135can communicate over a current access address. When the user input is input other than input to actuate the components120, such as input to close an application that provides commands to the components120, the computer110and/or the portable device135can determine that the user no longer intends to actuate the components120and can generate the second access address. Thus, while the user is communicating with the computer110, the portable device135and the computer110use the current access address, and when the user no longer intends to communicate with the computer110, the computer110and/or the portable device135can generate the second access address.

The computer110and/or the portable device135can generate the second access address by ceasing communication between the computer110and/or the portable device135. To “cease” communication means to disconnect the portable device135from communication with the computer110and end a current communication session between the portable device135and the computer110. For example, the portable device135can send a message to the computer110via Bluetooth® Low Energy protocol to end a current communication session between the portable device135and the computer110. That is, upon ceasing communication, the computer110and/or the portable device135can determine to use a different access address to communicate than the access address used prior to ceasing communication. Using a new access address each time the computer110and the portable device135initiate communication prevents eavesdroppers from using a previously determined access address to intercept communications. The portable device135can cease communication with the computer110upon identifying the user input to the portable device135or the change of output of the portable device135, as described above. Upon ceasing communication, the portable device135can request the second access address from the computer110. Upon obtaining the second access address from the computer110, the portable device135can reestablish communication with the computer110via the second access address.

The computer110can be programmed to generate the second access address upon determining that the portable computing device135has ceased communication with the computer110, i.e., has ended a current communication session with the computer110. If the computer110attempts to reestablish communication with the portable device135with the current access address, the portable device135can transmit a request to the computer110via the current access address to generate the second access address. Upon generating the second access address, which as explained below can be done in a secure manner, the computer110can reestablish communication with the portable device135via the second access address. The computer110can receive a command from the portable device135to actuate one or more vehicle components120via the second access address. Upon receiving the command, the computer110can actuate the one or more components120and one more sensors115that collect data used in actuation of the components120. For example, if the computer110receives a command to actuate a propulsion120, the computer110can actuate a fuel level sensor115in a fuel tank, an air/fuel ratio sensor115, a fuel injector sensor115, etc., to collect data that the computer110can use to activate the propulsion120.

The computer110and/or the portable device135can generate the second access address using an address generator program. An “address generator program” is an algorithm or method to generate an access address. For example, the address generator program can be a Resolvable Private Address (RPA) program that generates an access address from an input random number and an input numeric key. The address generator program generates a randomly generated number and a hash and concatenates the random number and the hash to generate the access address. A “hash” is an output of a “hash” function that outputs a unique string of alphanumeric bits for a specific input numeric key. That is, while the hash appears random, only the specific numeric key can produce the specific hash. The randomly generated number can be generated using a convention pseudorandom number generator, e.g., a stream cipher, a Mersenne Twister, an AES block cipher, etc.

The computer110and/or the portable device135can input an encryption key to the address generator program to generate the second access address. An “encryption key” is a numeric value stored in both the portable device135and the computer110, e.g., a cryptographic public key. The computer110and/or the portable device135can generate the encryption key upon initiating communication and can share the encryption key with the other of the computer110or the portable device135. That is, the computer110and the portable device135can store the same encryption key. When the portable device135generates the encryption key, the portable device135can send the generated encryption key to the computer110via the first access address. When the computer110generates the encryption key, the portable device135can receive the encryption key from the computer110via the first access address. Alternatively or additionally, the portable device135can generate the encryption key upon identifying the change to operation of the portable device135.

The encryption key can be an Identity Resolving Key (IRK). An IRK is a key used to generate an access address with the address generator program, as described above. Each portable device135can include a unique IRK identifying the portable device135. The portable device135and/or the computer110can input the IRK to the hash function of the address generator program to generate an access address. That is, the output of the address generator function with the IRK input can be unique to the specific portable device135from which the IRK is received. The portable device135can share the IRK with the computer110with a conventional cryptographic protocol, e.g., Advanced Encryption Standard (AES), RSA encryption, etc.

FIG. 3is a diagram of an example process300for communicating between a vehicle computer110and a portable computing device135. The process300begins in a block305, in which the portable device135initiates communication with the vehicle computer110via a first access address. The vehicle computer110can broadcast an access address to nearby devices, and the portable device135requests to establish communication with the vehicle computer110via the access address. As described above, an access address is a set of numeric values that the portable device135and the computer110append to each communication to confirm that the communications are intended for the portable device135and the computer110.

Next, in a block310, the portable device135detects a change to operation of the portable device135. As described above, the portable device135can identify a change to operation of the portable device135is a new input or output from a current input or output of the portable device135. The change to the operation can be a change to an application on the portable device135that can result in a change or changes to the display screen. For example, the portable device135can detect a transition of the display to a darkened, power-saving mode. In another example, the portable device135can detect user input to an icon on the display.

Next, in a block315, the portable device135ceases communication with the computer110. That is, the portable device135ceases communication with the computer110via the current access address. The portable device135can send a message to the computer110that the portable device135will no longer accept messages with the current access address, ending communications between the portable device135and the computer110via the current access address.

Next, in a block320, the portable device135and/or the computer110generate a new access address. The portable device135and/or the computer110can generate the new access address with an address generator program. As described above, the address generator program can be a conventional algorithm that generates an access address from an input numeric value. For example, the address generator program can generate a pseudorandom number and an output of a hash function (i.e., a “hash”), and the access address can be the concatenation of the pseudorandom number and the hash.

Next, in a block325, the portable device135reestablishes communication with the computer110via the new access address. The portable device135or the computer110can send a message to the other of the portable device135and the computer110with the new access address. Then, the portable device135and the computer110can communicate via the new access address.

Next, in a block330, the portable device135provides a command to the computer110to actuate one or more vehicle components120. As described above, a user can provide input to the portable device135to actuate one or more vehicle components120, and the portable device135can provide a command to the computer110to actuate the one or more vehicle components120based on the user input. The computer110can, based on the command, actuate the one or more vehicle components120requested by the user.

Next, in a block335, the portable device135determines whether to continue the process300. For example, the portable device135can determine to continue the process300when the portable device135is within transmission range of Bluetooth® Low Energy communications with the computer110. If the portable device135determines to continue, the process300returns to the block310. Otherwise, the process300ends.

FIG. 4is a diagram of another example process400for communicating between a vehicle computer110and a portable computing device135. The process400begins in a block405, in which the portable device135initiates communication with the vehicle computer110via a first access address. As described above, the vehicle computer110can broadcast an access address to nearby devices, and the portable device135requests to establish communication with the vehicle computer110via the access address.

Next, in a block410, the portable device135detects a change to operation of the portable device135. As described above, the portable device135can identify changes to an application on the portable device135that result in a change to output by the portable device135. For example, the portable device135can detect a transition of the display to a darkened power-saving display mode as a change in output of the portable device135. In another example, the portable device135can detect physical user input to a portion of the display on which an icon is shown.

Next, in a block415, the portable device135and/or the computer110generate a new access address with an encryption key. As described above, the portable device135and/or the computer110can input an encryption key that is a numeric string into an address generator program to generate the new access address. For example, the encryption key can be an Identity Resolving Key (IRK), and the address generator program can be a Resolvable Private Address algorithm.

Next, in a block420, the portable device135or the computer110can send the new access address to the other of the portable device135and the computer110. For example, the portable device135or the computer110can broadcast the new access address, and the other of the portable device135and the computer110can initiate communications via the new access address. Then, the portable device135and the computer110can communicate via the new access address.

Next, in a block425, the portable device135provides a command to the computer110to actuate a vehicle component120via the new access address. As described above, a user can provide input to the portable device135to actuate one or more vehicle components120, and the portable device135can provide a command to the computer110to actuate the one or more vehicle components120based on the user input. The computer110can, based on the command, actuate the one or more vehicle components120requested by the user.

Next, in a block430, the portable device135determines whether to continue the process400. For example, the portable device135can determine to continue the process400when the portable device135is within transmission range of Bluetooth® Low Energy communications with the computer110. If the portable device135determines to continue, the process400returns to the block410. Otherwise, the process400ends.

Computing devices discussed herein, including the computer110, include processors and memories, the memories generally each including instructions executable by one or more computing devices such as those identified above, and for carrying out blocks or steps of processes described above. Computer executable instructions may be compiled or interpreted from computer programs created using a variety of programming languages and/or technologies, including, without limitation, and either alone or in combination, Java™, C, C++, Visual Basic, Java Script, Python, Perl, HTML, etc. In general, a processor (e.g., a microprocessor) receives instructions, e.g., from a memory, a computer readable medium, etc., and executes these instructions, thereby performing one or more processes, including one or more of the processes described herein. Such instructions and other data may be stored and transmitted using a variety of computer readable media. A file in the computer110is generally a collection of data stored on a computer readable medium, such as a storage medium, a random access memory, etc.

With regard to the media, processes, systems, methods, etc. described herein, it should be understood that, although the steps of such processes, etc. have been described as occurring according to a certain ordered sequence, such processes could be practiced with the described steps performed in an order other than the order described herein. It further should be understood that certain steps could be performed simultaneously, that other steps could be added, or that certain steps described herein could be omitted. For example, in the process400, one or more of the steps could be omitted, or the steps could be executed in a different order than shown inFIG. 4. In other words, the descriptions of systems and/or processes herein are provided for the purpose of illustrating certain embodiments and should in no way be construed so as to limit the disclosed subject matter.

The article “a” modifying a noun should be understood as meaning one or more unless stated otherwise, or context requires otherwise. The phrase “based on” encompasses being partly or entirely based on.