Patent Publication Number: US-9898602-B2

Title: System, apparatus, and method for adaptive observation of mobile device behavior

Description:
RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 13/627,401 entitled “System, Apparatus and Method for Adaptive Observation of Mobile Device Behavior,” filed Sep. 26, 2012, which claims the benefit of priority to U.S. Provisional Patent Application No. 61/646,590 entitled “System, Apparatus and Method for Adaptive Observation of Mobile Device Behavior” filed May 14, 2012; and U.S. Provisional Application No. 61/683,274, entitled “System, Apparatus and Method for Adaptive Observation of Mobile Device Behavior” filed Aug. 15, 2012, the entire contents of all which are hereby incorporated by reference for all purposes. 
    
    
     BACKGROUND 
     Cellular and wireless communication technologies have seen explosive growth over the past several years. This growth has been fueled by better communications, hardware, larger networks, and more reliable protocols. Wireless service providers are now able to offer their customers an ever-expanding array of features and services, and provide users with unprecedented levels of access to information, resources, and communications. To keep pace with these service enhancements, mobile electronic devices (e.g., cellular phones, tablets, laptops, etc.) have become more powerful and complex than ever. This complexity has created new opportunities for malicious software, software conflicts, hardware faults, and other similar errors or phenomena to negatively impact a mobile device&#39;s long-term and continued performance and power utilization levels. Accordingly, identifying and correcting the conditions and/or mobile device behaviors that may negatively impact the mobile device&#39;s long term and continued performance and power utilization levels is beneficial to consumers. 
     SUMMARY 
     The various aspects include methods of observing mobile device behaviors over a period of time to recognize mobile device behaviors inconsistent with normal operation patterns, the method including dynamically determining in a processor which mobile device behaviors are to be observed, and adaptively observing the determined mobile device behaviors to identify a suspicious mobile device behavior from a limited set of observations. In an aspect, the method may include controlling an observation granularity of the adaptive observation. In a further aspect, dynamically determining which mobile device behaviors are to be observed may include observing mobile device behaviors over a period of time to recognize mobile device behaviors that are inconsistent with normal operation patterns, and identifying a limited set of behaviors associated with inconsistent operations as the mobile device behaviors to be observed. 
     In a further aspect, the operations of dynamically determining which mobile device behaviors are to be observed and controlling the observation granularity of the adaptive observation are accomplished within an observer daemon operating within a system kernel. In a further aspect, identifying a limited set of behaviors associated with inconsistent operations as the mobile device behaviors to be observed may include receiving behavior inputs from one or more of a high-level application, a system kernel, and a driver API after filtering by an adaptive filter, receiving a context input regarding operations of the mobile device, performing spatial correlations of the received behaviors and the received context, and generating a behavior vector. In a further aspect, identifying a limited set of behaviors associated with inconsistent operations as the mobile device behaviors to be observed further may include performing temporal correlations of the received behaviors and the received context input, in which generating a behavior vector may include generating a behavior vector based on a result of the spatial and temporal correlations. In a further aspect, identifying a limited set of behaviors associated with inconsistent operations as behaviors to be observed further may include storing the generated behavior vector in a secure memory. 
     Further aspects include a computing device that may include a processor, means for dynamically determining which mobile device behaviors are to be observed to identify behaviors inconsistent with normal operation patterns, and means for adaptively observing the determined mobile device behaviors to identify a suspicious mobile device behavior from a limited set of observations. In an aspect, the computing device may include means for controlling an observation granularity of the adaptive observation. In a further aspect, means for dynamically determining which mobile device behaviors are to be observed may include means for observing mobile device behaviors over a period of time to recognize mobile device behaviors that are inconsistent with normal operation patterns, and means for identifying a limited set of behaviors associated with inconsistent operations as the mobile device behaviors to be observed. 
     In a further aspect, the computing device may include observer daemon means, in which the observer daemon means may include means for dynamically determining which mobile device behaviors are to be observed and means for controlling the observation granularity of the adaptive observation within an observer daemon operating within a system kernel. In a further aspect, means for identifying a limited set of behaviors associated with inconsistent operations as the mobile device behaviors to be observed may include means for receiving behavior inputs from one or more of a high-level application, a system kernel, and a driver API after filtering by an adaptive filter, means for receiving a context input regarding operations of the mobile device, means for performing spatial correlations of the received behaviors and the received context, and means for generating a behavior vector. In a further aspect, means for identifying a limited set of behaviors associated with inconsistent operations as the mobile device behaviors to be observed further may include means for performing temporal correlations of the received behaviors and the received context input, in which means for generating a behavior vector may include means for generating a behavior vector based on a result of the spatial and temporal correlations. In a further aspect, means for identifying a limited set of behaviors associated with inconsistent operations as behaviors to be observed further may include means for storing the generated behavior vector in a secure memory. 
     Further aspects include a computing device that may include a processor configured with processor-executable instructions to perform operations that may include a processor configured with processor-executable instructions to perform operations including dynamically determining which mobile device behaviors are to be observed to identify behaviors inconsistent with normal operation patterns, and adaptively observing the determined mobile device behaviors to identify a suspicious mobile device behavior from a limited set of observations. In an aspect, the processor is configured with processor-executable instructions to perform operations further including controlling an observation granularity of the adaptive observation. 
     In a further aspect, the processor is configured with processor-executable instructions such that dynamically determining which mobile device behaviors are to be observed may include observing mobile device behaviors over a period of time to recognize mobile device behaviors that are inconsistent with normal operation patterns, and identifying a limited set of behaviors associated with inconsistent operations as the mobile device behaviors to be observed. In a further aspect, the processor is configured with processor-executable instructions such that the operations of dynamically determining which mobile device behaviors are to be observed and controlling the observation granularity of the adaptive observation are accomplished within an observer daemon operating within a system kernel. In a further aspect, the processor is configured with processor-executable instructions such that identifying a limited set of behaviors associated with inconsistent operations as the mobile device behaviors to be observed may include receiving behavior inputs from one or more of a high-level application, a system kernel, and a driver API after filtering by an adaptive filter, receiving a context input regarding operations of the mobile device, performing spatial correlations of the received behaviors and the received context, and generating a behavior vector. 
     In a further aspect, the processor is configured with processor-executable instructions such that identifying a limited set of behaviors associated with inconsistent operations as the mobile device behaviors to be observed further may include performing temporal correlations of the received behaviors and the received context input, and in which the processor is configured with processor-executable instructions such that generating a behavior vector may include generating a behavior vector based on a result of the spatial and temporal correlations. In a further aspect, the processor is configured with processor-executable instructions such that identifying a limited set of behaviors associated with inconsistent operations as behaviors to be observed further may include storing the generated behavior vector in a secure memory. 
     Further aspects include a non-transitory server-readable storage medium having stored thereon processor-executable instructions configured to cause a computing device to perform operations that may include dynamically determining which mobile device behaviors are to be observed to recognize mobile device behaviors inconsistent with normal operation patterns, and adaptively observing the determined mobile device behaviors to identify a suspicious mobile device behavior from a limited set of observations. In an aspect, the stored processor-executable instructions may be configured to cause a processor of a mobile device to perform operations further including controlling an observation granularity of the adaptive observation. 
     In a further aspect, dynamically determining which mobile device behaviors are to be observed may include observing mobile device behaviors over a period of time to recognize mobile device behaviors that are inconsistent with normal operation patterns, and identifying a limited set of behaviors associated with inconsistent operations as the mobile device behaviors to be observed. In a further aspect, operations of dynamically determining which mobile device behaviors are to be observed and controlling the observation granularity of the adaptive observation are accomplished within an observer daemon operating within a system kernel. In a further aspect, identifying a limited set of behaviors associated with inconsistent operations as the mobile device behaviors to be observed may include receiving behavior inputs from one or more of a high-level application, a system kernel, and a driver API after filtering by an adaptive filter, receiving a context input regarding operations of the mobile device, performing spatial correlations of the received behaviors and the received context, and generating a behavior vector. 
     In a further aspect, identifying a limited set of behaviors associated with inconsistent operations as the mobile device behaviors to be observed further may include performing temporal correlations of the received behaviors and the received context input, in which generating a behavior vector may include generating a behavior vector based on a result of the spatial and temporal correlations. In a further aspect, identifying a limited set of behaviors associated with inconsistent operations as behaviors to be observed further may include storing the generated behavior vector in a secure memory. 
     The various aspects also include methods of performing on a mobile device processor real-time behavior analysis of mobile device behaviors to generate coarse observations, identifying suspicious behavior from the coarse observations, dynamically determining the mobile device behaviors that require further observation in greater detail, dynamically determining a level of detail required for the further observation, performing finer observations based on the determined level of detail required for the further observation, and identifying suspicious behavior from the finer observations. In an aspect, the method may include performing mobile devices operations to correct the identified suspicious behavior. In a further aspect, the method may include performing spatial and temporal correlations of observed mobile device behaviors to detect high-level mobile device behaviors. 
     Further aspects include a computing device that may include a processor, means for performing real-time behavior analysis of mobile device behaviors to generate coarse observations, means for identifying suspicious behavior from the coarse observations, means for dynamically determining the mobile device behaviors that require further observation in greater detail, means for dynamically determining a level of detail required for the further observation, means for performing finer observations based on the determined level of detail required for the further observation, and means for identifying suspicious behavior from the finer observations. In an aspect, the computing device may include means for performing mobile devices operations to correct the identified suspicious behavior. In a further aspect, the computing device may include means for performing spatial and temporal correlations of observed mobile device behaviors to detect high-level mobile device behaviors. 
     Further aspects include a computing device that may include a processor configured with processor-executable instructions to perform operations that may include a processor configured with processor-executable instructions to perform operations including performing real-time behavior analysis of mobile device behaviors to generate coarse observations, identifying suspicious behavior from the coarse observations, dynamically determining the mobile device behaviors that require further observation in greater detail, dynamically determining a level of detail required for the further observation, performing finer observations based on the determined level of detail required for the further observation, and identifying suspicious behavior from the finer observations. In an aspect, the processor is configured with processor-executable instructions to perform operations further including performing mobile devices operations to correct the identified suspicious behavior. In a further aspect, the processor is configured with processor-executable instructions to perform operations further including performing spatial and temporal correlations of observed mobile device behaviors to detect high-level mobile device behaviors. 
     Further aspects include a non-transitory server-readable storage medium having stored thereon processor-executable instructions configured to cause a computing device to perform operations that may include performing real-time behavior analysis of mobile device behaviors to generate coarse observations, identifying suspicious behavior from the coarse observations, dynamically determining the mobile device behaviors that require further observation in greater detail, dynamically determining a level of detail required for the further observation, performing finer observations based on the determined level of detail required for the further observation, and identifying suspicious behavior from the finer observations. In an aspect, the stored processor-executable software instructions are configured to cause a processor to perform operations including performing mobile devices operations to correct the identified suspicious behavior. In a further aspect, the stored processor-executable software instructions are configured to cause a processor to perform operations including performing spatial and temporal correlations of observed mobile device behaviors to detect high-level mobile device behaviors. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated herein and constitute part of this specification, illustrate exemplary aspects of the invention, and together with the general description given above and the detailed description given below, serve to explain the features of the invention. 
         FIG. 1  is an architectural diagram of an example system on chip suitable for implementing the various aspects. 
         FIG. 2  is a block diagram illustrating example logical components and information flows in a computing system configured to perform dynamic and adaptive observations in accordance with the various aspects. 
         FIG. 3  is a block diagram illustrating example logical components and information flows in an observer module configured to perform dynamic and adaptive observations in accordance with an aspect. 
         FIG. 4  is a block diagram illustrating logical components and information flows in a computing system implementing observer modules in accordance with an aspect. 
         FIG. 5A  is block diagram illustrating logical components and information flows in a computing system implementing observer modules in accordance with another aspect. 
         FIG. 5B  is block diagram illustrating logical components and information flows in a computing system implementing observer modules in accordance with another aspect. 
         FIG. 6A  is block diagram illustrating logical components and information flows in a computing system implementing observer modules in accordance with another aspect. 
         FIG. 6B  is block diagram illustrating logical components and information flows in a computing system implementing observer modules in accordance with another aspect. 
         FIG. 7A  is a block diagram illustrating logical components and information flows in a computing system implementing observer daemons in accordance with an aspect. 
         FIG. 7B  is a block diagram illustrating logical components and information flows in a computing system implementing observer daemons in accordance with another aspect. 
         FIG. 8A  is a block diagram illustrating logical components and information flows in a computing system implementing observer daemons in accordance with another aspect. 
         FIG. 8B  is a block diagram illustrating logical components and information flows in a computing system implementing observer daemons in accordance with another aspect. 
         FIG. 9  is a process flow diagram illustrating an aspect method for performing adaptive observations on mobile devices. 
         FIG. 10  is a process flow diagram illustrating another aspect method for performing adaptive observations on mobile devices. 
         FIG. 11  is a process flow diagram illustrating another aspect method for performing adaptive observations on mobile devices. 
         FIG. 12  is a component block diagram of a mobile device suitable for use in an aspect. 
         FIG. 13  is a component block diagram of a server device suitable for use in an aspect. 
     
    
    
     DETAILED DESCRIPTION 
     The various aspects will be described in detail with reference to the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. References made to particular examples and implementations are for illustrative purposes, and are not intended to limit the scope of the invention or the claims. 
     The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any implementation described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other implementations. 
     The terms “mobile computing device” and “mobile device” are used interchangeably herein to refer to any one or all of cellular telephones, smartphones, personal or mobile multi-media players, personal data assistants (PDA&#39;s), laptop computers, tablet computers, smartbooks, ultrabooks, palm-top computers, wireless electronic mail receivers, multimedia Internet enabled cellular telephones, wireless gaming controllers, and similar personal electronic devices which include a memory, a programmable processor for which performance is important, and operate under battery power such that power conservation methods are of benefit. While the various aspects are particularly useful for mobile computing devices, such as smartphones, which have limited resources and run on battery, the aspects are generally useful in any electronic device that includes a processor and executes application programs. 
     Computer program code or “program code” for execution on a programmable processor for carrying out operations of the various aspects may be written in a high level programming language such as C, C++, C#, Smalltalk, Java, JavaScript, Visual Basic, a Structured Query Language (e.g., Transact-SQL), Perl, or in various other programming languages. Program code or programs stored on a computer readable storage medium as used herein to refer to machine language code (such as object code) whose format is understandable by a processor. 
     The term “performance degradation” is used herein to refer to a wide variety of undesirable mobile device operations and characteristics, such as longer processing times, lower battery life, loss of private data, malicious economic activity (e.g., sending unauthorized premium SMS message), operations relating to commandeering the mobile device or utilizing the phone for spying or botnet activities, etc. 
     Many mobile computing devices operating system kernels are organized into a user space (where non-privileged code runs) and a kernel space (where privileged code runs). This separation is of particular importance in Android® and other general public license (GPL) environments where code that is part of the kernel space must be GPL licensed, while code running in the user-space may not be GPL licensed. It should be understood that the various software components/modules discussed here may be implemented in either the kernel space or the user space, unless expressly stated otherwise. 
     The term “system on chip” (SOC) is used herein to refer to a single integrated circuit (IC) chip that contains multiple resources and/or processors integrated on a single substrate. A single SOC may contain circuitry for digital, analog, mixed-signal, and radio-frequency functions. A single SOC may also include any number of general purpose and/or specialized processors (digital signal processors, modem processors, video processors, etc.), memory blocks (e.g., ROM, RAM, Flash, etc.), and resources (e.g., timers, voltage regulators, oscillators, etc.). SOCs may also include software for controlling the integrated resources and processors, as well as for controlling peripheral devices. 
     The term “multicore processor” is used herein to refer to a single integrated circuit (IC) chip or chip package that contains two or more independent processing cores (e.g., CPU cores) configured to read and execute program instructions. A SOC may include multiple multicore processors, and each processor in an SOC may be referred to as a core. The term “multiprocessor” is used herein to refer to a system or device that includes two or more processing units configured to read and execute program instructions. 
     Generally, the performance and power efficiency of a mobile device degrade over time. Recently, anti-virus companies (e.g., McAfee, Symantec, etc.) have begun marketing mobile anti-virus, firewall, and encryption products that aim to slow this degradation. However, many of these solutions rely on the periodic execution of a computationally-intensive scanning engine on the mobile device, which may consume many of the mobile device&#39;s processing and battery resources, slow or render the mobile device useless for extended periods of time, and/or otherwise degrade the user experience. In addition, these solutions are typically limited to detecting known viruses and malware, and do not address the multiple complex factors and/or the interactions that often combine to contribute to a mobile device&#39;s degradation over time (e.g., when the performance degradation is not caused by viruses or malware). For these and other reasons, existing anti-virus, firewall, and encryption products do not provide adequate solutions for identifying the numerous factors that may contribute to a mobile device&#39;s degradation over time, for preventing mobile device degradation, or for efficiently restoring an aging mobile device to its original condition. 
     Various other solutions exist for modeling the behavior of processes or application programs executing on a computing device, and such behavior models may be used to differentiate between malicious and benign process/programs on computing devices. However, these existing modeling solutions are not suitable for use on mobile devices because such solutions generally require the execution of computationally-intensive processes that consume a significant amount of processing, memory, and energy resources, all of which may be scarce on mobile devices. In addition, these solutions are generally limited to evaluating the behavior of individual application programs or processes, and do not provide an accurate or complete model of the performance-degrading mobile device behaviors. For these and other reasons, existing modeling solutions are not adequate for identifying the numerous factors that may contribute to a mobile device&#39;s degradation over time, for preventing mobile device degradation, or for efficiently restoring an aging mobile device to its original condition. 
     There are a variety of factors that may contribute to the degradation in performance and power utilization levels of a mobile device over time, including poorly designed software applications, malware, viruses, fragmented memory, background processes, etc. However, due to the complexity of modern mobile devices, it is increasingly difficult for users, operating systems, and/or application programs (e.g., anti-virus software, etc.) to accurately and efficiently identify the sources of such problems and/or to provide adequate remedies to identified problems. As a result, mobile device users currently have few remedies for preventing the degradation in performance and power utilization levels of a mobile device over time, or for restoring an aging mobile device to its original performance and power utilization levels. 
     The various aspects provide devices, systems, and methods for efficiently identifying, preventing, and/or correcting the conditions and/or mobile device behaviors that often degrade a mobile device&#39;s performance and/or power utilization levels over time. 
     As mentioned above, mobile devices are resource constrained systems that have relatively limited processing, memory, and energy resources. As also mentioned above, modern mobile devices are complex systems, and there are a large number (i.e., thousands) of factors that may contribute to the mobile device&#39;s degradation over time. Due to these constraints, it is often not feasible to monitor/observe all the various processes, behaviors, or factors (or combinations thereof) that may degrade performance and/or power utilization levels of the complex yet resource-constrained systems of modern mobile devices. 
     To overcome the above mentioned limitations of existing solutions, the various aspects intelligently, dynamically, and/or adaptively determine mobile device behaviors that are to be observed, the number of behaviors that are to be observed, and the level of detail (i.e., granularity) at which the mobile device behaviors are to be observed. The various aspects efficiently identify suspicious or performance-degrading mobile device behaviors without consuming an excessive amount of processing, memory, or energy resources. Various aspects may correct suspicious or performance-degrading mobile device behaviors. Various aspects may prevent the identified suspicious or performance-degrading mobile device behaviors from degrading the performance and power utilization levels of a mobile device over time. Various aspects may restore an aging mobile device to its original performance and power utilization levels. 
     In an aspect, a mobile device processor may be configured to observe any or all of library application programming interface (API) calls, system call APIs, file-system operations, networking sub-system operations, driver API calls for the numerous sensors, state changes, and other similar events/operations at a high level, and perform real-time behavior analysis operations based on these high level observations to identify programs/processes that may contribute to the mobile device&#39;s degradation over time (e.g., programs that are actively malicious, poorly written, etc.). The mobile device processor may be configured to intelligently increase the level of detail (i.e., granularity) at which the mobile device behaviors are to be observed until enough information is available to identify and/or correct the cause of a suspicious or performance-degrading mobile device behavior. 
     In an aspect, the mobile device processor may be configured to dynamically change the set of observed behaviors (e.g., by selecting new behaviors to observe, observing fewer behaviors, etc.) based on the results of the on-line real-time analysis operations and/or the availability of system resources. 
     In various aspects, the mobile device processor may be configured to dynamically adjust the observation granularity (i.e., the level of detail at which mobile device behaviors are observed) based on the results of the real-time analysis operations and/or based on the availability of system resources. For example, in various aspects, the mobile device processor may be configured to recursively increase the granularity of one or more observations (i.e., make finer or more detailed observations) until a source of a suspicious or performance-degrading mobile device behavior is identified, until a processing threshold is reached, or until the mobile device processor determines that the source of the suspicious or performance-degrading mobile device behavior cannot be identified from further increases in observation granularity. 
     In an aspect, the mobile device processor may be configured to dynamically adjust the observation granularity based on the availability of system resources. For example, the mobile device processor may be configured to increase the observation granularity in response to determining that mobile device resources are available or underutilized, or that the mobile is currently connected to a power supply, and/or to reduce the observation granularity in response to determining that the computing device is under heavy load or low battery. 
     In an aspect, an observer process/daemon/module/sub-system (herein collectively referred to as a “module”) of the mobile device may instrument various application programming interfaces (APIs) at various levels of the mobile device system, collect information from the instrumented APIs, and generate a behavior vector based on the collected information. The observer module may send the generated behavior vector to an analyzer module (e.g., via a memory write operation, etc.) of the mobile device, which may generate spatial and/or temporal correlations based on information included in the behavior vector and/or information collected from various other mobile device sub-systems. The generated spatial and/or temporal correlations may be used by various modules (e.g., by an actuation module, etc.) of the mobile device to identify and/or respond to behaviors that are determined to have a high probability of negatively impacting the mobile device&#39;s performance or battery consumption levels. 
     The various aspects may be implemented on a number of single processor and multiprocessor systems, including a system-on-chip (SOC).  FIG. 1  is an architectural diagram illustrating an example system-on-chip (SOC)  100  architecture that may be used in computing devices implementing the various aspects. The SOC  100  may include a number of heterogeneous processors, such as a digital signal processor (DSP)  102 , a modem processor  104 , a graphics processor  106 , and an application processor  108 . The SOC  100  may also include one or more coprocessors  110  (e.g., vector co-processor) connected to one or more of the heterogeneous processors  102 ,  104 ,  106 ,  108 . Each processor  102 ,  104 ,  106 ,  108 ,  110  may include one or more cores, and each processor/core may perform operations independent of the other processors/cores. For example, the SOC  100  may include a processor that executes a first type of operating system (e.g., FreeBSD, LINUX, OS X, etc.) and a processor that executes a second type of operating system (e.g., Microsoft Windows 8). 
     The SOC  100  may also include analog circuitry and custom circuitry  114  for managing sensor data, analog-to-digital conversions, wireless data transmissions, and for performing other specialized operations, such as processing encoded audio signals for games and movies. The SOC  100  may further include system components and resources  116 , such as voltage regulators, oscillators, phase-locked loops, peripheral bridges, data controllers, memory controllers, system controllers, access ports, timers, and other similar components used to support the processors and clients running on a computing device. 
     The system components  116  and custom circuitry  114  may include circuitry to interface with peripheral devices, such as cameras, electronic displays, wireless communication devices, external memory chips, etc. The processors  102 ,  104 ,  106 ,  108  may be interconnected to one or more memory elements  112 , system components, and resources  116  and custom circuitry  114  via an interconnection/bus module  124 , which may include an array of reconfigurable logic gates and/or implement a bus architecture (e.g., CoreConnect, AMBA, etc.). Communications may be provided by advanced interconnects, such as high performance networks-on chip (NoCs). 
     The SOC  100  may further include an input/output module (not illustrated) for communicating with resources external to the SOC, such as a clock  118  and a voltage regulator  120 . Resources external to the SOC (e.g., clock  118 , voltage regulator  120 ) may be shared by two or more of the internal SOC processors/cores (e.g., DSP  102 , modem processor  104 , graphics processor  106 , applications processor  108 , etc.). 
     In addition to the SOC  100  discussed above, the various aspects may be implemented in a wide variety of computing systems, which may include a single processor, multiple processors, multicore processors, or any combination thereof. 
       FIG. 2  illustrates example logical components and information flows in a computing system  200  configured to perform dynamic and adaptive observations in accordance with the various aspects. In the example illustrated in  FIG. 2 , the computing system  200  includes a coarse observer module  202 , an analyzer module  204 , an external context information module  206 , and an actuation module  208 . In various aspects, such modules may be implemented in software, hardware, or any combination thereof. In various aspects, the modules may be implemented within parts of the operating system (e.g., within the kernel, in the kernel space, in the user space, etc.), within separate programs or applications, in specialized hardware buffers or processors, or any combination thereof. In an aspect, one or more of the modules may be implemented as software instructions executing on one or more processors of the mobile device. 
     The observer module  202  may be configured to instrument/coordinate application programming interfaces (APIs) at various levels/modules of the mobile device, and monitor/observe mobile device operations and events (e.g., system events, state changes, etc.) at the various levels/modules via the instrumented APIs, collect information pertaining to the observed operations/events, intelligently filter the collected information, generate one or more observations based on the filtered information, efficiently store the generated observations in a memory, and send (e.g., via memory writes, function calls, etc.) the generated observations to the analyzer module  204 . 
     The analyzer module  204  may include intelligence for utilizing the limited set of information (i.e., coarse observations) to identify behaviors, processes, or programs that are contributing to (or are likely to contribute to) the device&#39;s degradation over time, or which may otherwise cause problems on the device. For example, the analyzer module  204  may be configured to analyze information (e.g., in the form of observations) collected from various modules (e.g., the observer module  202 , external context information module  206 , etc.), learn the normal operational behaviors of the mobile device, generate behavior models of the mobile device&#39;s behaviors, and compare the generated models to information/observations received from the observer module  202  to identify suspicious mobile device behaviors. 
     As mentioned above, the observer module  202  may monitor/observe mobile device operations and events. In various aspects, observing mobile device operations and events may include collecting information pertaining to any or all of library API calls in an application framework or run-time libraries, system call APIs, file-system and networking sub-system operations, device (including sensor devices) state changes, and other similar events. In an aspect, the observer module  202  may monitor file system activity, which may include searching for filenames, categories of file accesses (personal info or normal data files), creating or deleting files (e.g., type exe, zip, etc.), file read/write/seek operations, changing file permissions, etc. In an aspect, the observer module  202  may monitor data network activity, which may include types of connections, protocols, port numbers, server/client that the device is connected to, the number of connections, volume or frequency of communications, etc. In an aspect, the observer module  202  may monitor phone network activity, which may include monitoring the type and number of calls or messages (e.g., SMS, etc.) sent out, received, or intercepted (e.g., the number of premium calls placed). In an aspect, the observer module  202  may monitor the system resources that are used, which may include monitoring the number of forks, memory uses, number of files open, etc. In an aspect, the observer module  202  may monitor the device state, which may include monitoring various factors, such as whether the display is on or off, whether the device is locked or unlocked, the amount of battery remaining, the state of the camera, etc. In an aspect, the observer module  202  may also monitor inter-process communications (IPC) by, for example, monitoring intents to crucial services (browser, contracts provider, etc.), the degree of inter-process communications, pop-up windows, etc. 
     To reduce the number of factors monitored to a manageable level, in operation 1 illustrated in  FIG. 2 , the observer module  202  may perform coarse observations by monitoring/observing a small subset of the factors that could contribute to the mobile device&#39;s degradation, and send the coarse observations to the analyzer module  204 . In an embodiment, the initial set of behaviors and/or subset of the factors may be selected by analysis of benign and problematic applications on mobile devices. 
     In operation 2, the analyzer module  204  may receive the coarse observations from the observer module  202  and identify subsystems, processes, and/or applications associated with the received coarse observations that may potentially contribute to the mobile device&#39;s degradation. This may be achieved by, for example, the analyzer module  204  comparing the received information with contextual information received from the external context information module  206 . 
     In operation 3, the analyzer module  204  may instruct the observer module  202  to perform or enable deeper logging/observations or final logging on the identified subsystems, processes or applications. In operation 4, the observer module  202  may perform deeper observations on the identified subsystems, processes or applications. In operation 5, the observer module  202  may send the results of the deeper observations to the analyzer module  204  for further (and deeper) analysis. Operations 1-5 may be repeated until the source of a problem is identified or until it is determined that the identified subsystems, processes or applications are not likely to cause problems or degradation. In operation 6, the analyzer module  204  may send the results of the analysis to the actuation module  208 , which may receive the results and perform operations to heal, cure, isolate, or otherwise fix the identified problem. 
     In an aspect, the observer module  202  and the analyzer module  204  may provide, either individually or collectively, real-time behavior analysis of the computing system&#39;s behaviors to identify suspicious behavior from limited and coarse observations, to dynamically determine behaviors to observe in greater detail, and to dynamically determine the level of detail required for the observations. In this manner, the observer module  202  enables the computing system  200  to efficiently identify and prevent problems from occurring on mobile devices without requiring a large amount of processor, memory, or battery resources on the device. 
     In an aspect, the observer module  202  may store the observations in a space efficient and query-service-time efficient manner to reduce the performance-impact on benign applications. The observer module  202  may provide the system with various observer modes to enable multi-level logging (e.g., fine grained and coarse-grained logging). The observer module  202  may provide the ability to automatically and dynamically switch between the different observer modes. The observer module  202  may monitor and restrict process/application that may exhaust system resources. The observer module  202  may manage communications (e.g., non-secure to secure world) overhead, such that the overhead is minimal and flow control is maintained/performed efficiently. 
     In an aspect, the analyzer module  204  may be configured to receive and analyze information collected by various mobile device sub-systems and/or over various time periods to learn the normal operational behaviors of the mobile device under a variety of contexts and conditions, and generate models of normal mobile device behaviors under the various contexts/conditions. In an aspect, the analyzer module  204  may be configured to correlate the received observations against the generated behavior models, and perform behavior analysis operations based on the correlations to determine whether the received observations conflict with (or do not match) the learned normal operational behaviors. 
       FIG. 3  illustrates example logical components and information flows in an observer module  202  of a computing system configured to perform dynamic and adaptive observations in accordance with an aspect. The observer module  202  may include an adaptive filter module  302 , a throttle module  304 , an observer mode module  306 , a high-level behavior detection module  308 , a behavior vector generator  310 , and a secure buffer  312 . The high-level behavior detection module  308  may include a spatial correlation module  314  and a temporal correlation module  316 . 
     The observer mode module  306  may receive control information from various sources, which may include an analyzer unit (e.g., the analyzer module  204  described above with reference to  FIG. 2 ) and/or an application API. The observer mode module  306  may send control information pertaining to various observer modes to the adaptive filter module  302  and the high-level behavior detection module  308 . 
     The adaptive filter module  302  may receive data/information from multiple sources, and intelligently filter the received information to generate a smaller subset of information selected from the received information. This filter may be adapted based on information or control received from the analyzer module, or a higher-level process communicating through an API. The filtered information may be sent to the throttle module  304 , which may be responsible for controlling the amount of information flowing from the filter to ensure that the high-level behavior detection module  308  does not become flooded or overloaded with requests or information. 
     The high-level behavior detection module  308  may receive data/information from the throttle module  304 , control information from the observer mode module  306 , and context information from other components of the mobile device. The high-level behavior detection module  308  may use the received information to perform spatial and temporal correlations to detect or identify high level behaviors that may cause the device to perform at sub-optimal levels. The results of the spatial and temporal correlations may be sent to the behavior vector generator  310 , which may receive the correlation information and generate a behavior vector that describes the behaviors of particular process, application, or sub-system. In an aspect, the behavior vector generator  310  may generate the behavior vector such that each high-level behavior of a particular process, application, or sub-system is an element of the behavior vector. In an aspect, the generated behavior vector may be stored in a secure buffer  312 . Examples of high-level behavior detection may include detection of the existence of a particular event, the amount or frequency of another event, the relationship between multiple events, the order in which events occur, time differences between the occurrence of certain events, etc. 
     In the various aspects, the observer module  202  may perform adaptive observations and control the observation granularity. That is, the observer module  202  may dynamically identify the relevant behaviors that are to be observed, and dynamically determine the level of detail at which the identified behaviors are to be observed. In this manner, the observer module  202  enables the system to monitor the behaviors of the mobile device at various levels (e.g., multiple coarse and fine levels). The observer module  202  may enable the system to adapt to what is being observed. The observer module  202  may enable the system to dynamically change the factors/behaviors being observed based on a focused subset of information, which may be obtained from a wide verity of sources. 
     As discussed above, the observer module  202  may perform adaptive observation techniques and control the observation granularity based on information received from a variety of sources. For example, the high-level behavior detection module  308  may receive information from the throttle module  304 , the observer mode module  306 , and context information received from other components (e.g., sensors) of the mobile device. As an example, a high-level behavior detection module  308  performing temporal correlations might detect that a camera has been used and that the mobile device is attempting to upload the picture to a server. The high-level behavior detection module  308  may also perform spatial correlations to determine whether an application on the mobile device took the picture while the device was holstered and attached to the user&#39;s belt. The high-level behavior detection module  308  may determine whether this detected high-level behavior (e.g., usage of the camera while holstered) is a behavior that is acceptable or common, which may be achieved by comparing the current behavior with past behaviors of the mobile device and/or accessing information collected from a plurality of devices (e.g., information received from a crowd-sourcing server). Since taking pictures and uploading them to a server while holstered is an unusual behavior (as may be determined from observed normal behaviors in the context of being holstered), in this situation the high-level behavior detection module  308  may recognize this as a potentially threatening behavior and initiate an appropriate response (e.g., shutting off the camera, sounding an alarm, etc.). 
     In an aspect, the observer module  202  may be implemented in multiple parts. 
       FIG. 4  illustrates logical components and information flows in an example computing system  400  implementing an observer module in accordance with an aspect. The illustrated computing system  400  includes an application framework  402 , a run time library  404 , a user log API  406 , and a logger library  408  in the user space. The computing system  400  may include a kernel core  410 , kernel drivers  412 , a kernel log API  414 , an observer logger  424 , a filter rules module  416 , a throttling rules module  418 , a ring buffer  422 , and an observer daemon  420  in the kernel space. In an aspect, the ring buffer  422  may be a fixed-sized and/or circular buffer. In an aspect, the combination of the user log API  406  and the kernel log API  414  may constitute the observer logger  424 . In an aspect, the combination of the observer daemon  420  and the observer logger  424  may constitute the observer module  202 . 
     The application framework  402  and the run time library  404  may be preexisting software code/components of the mobile device, each of which may be instrumented with logic to monitor activities and send information to the user log API  406  in the user space. The user log API  406  may provide an API that enables the user space applications to communicate with the kernel via the kernel log API  414 . 
     In an aspect, the observer logger  414  may be automatically invoked whenever a particular event, action, or API (e.g., an API identified in a list of APIs as being of particular importance) is invoked, and the corresponding information may be stored in the ring buffer  422 . The information stored in the ring buffer  422  may include, for example, information for identifying the caller, information for identifying the exact function being called, the parameters that have been passed to the function call, and other similar information. In an aspect, this information may be stored in the ring buffer  422  in a raw format. Alternatively, the ring buffer  422  may be used to store information after the log has been processed. 
     The observer logger  424  may be controlled by a set of filter and throttling rules  416 ,  418 . The filter rules  416  may specify whether a particular API is to be logged or not. The throttling rules  418  may specify conditions under which the system is to termination the logging/monitoring of a specific API to prevent overloads. 
     The filter and throttling rules  416 ,  418  may be created, updated, and/or maintained by the observer daemon  420 . For example, if after observing the mobile device for ten minutes, the observer daemon  428  decides that a particular API is no longer of interest (e.g., it is not providing the system with useful information), the observer daemon  420  may update the filter rules  416  such that events relating to that particular API are no longer monitored/logged. 
       FIG. 5A  illustrates logical components and information flows in a computing system  500  implementing an observer module  202  in accordance with another aspect. The computing system  500  illustrated in  FIG. 5A  includes all the components described above with reference to  FIG. 4 , except that the filter rules  416  are enforced on the user log API  406  in the user space and/or kernel space on the device. Thus, instead of each call coming to the observer logger  424  and the observer logger  424  deciding whether the call should be logged or not (as described with reference to  FIG. 4 ), the filter rules  416  may be implemented within the instrumentations (e.g., user log API, etc.) such that the call itself will not reach the logger based on the filter rules  416 . Implementing the configuration illustrated in  FIG. 5A  may further improve the mobile device efficiency because function calls do not need to be made to a logger inside the kernel. 
       FIG. 5B  illustrates logical components and information flows in a computing system  550  implementing an observer module in accordance with yet another aspect. The computing system  550  illustrated in  FIG. 5B  includes all the components described above with reference to  FIG. 5A , except that the observer daemon  420  is in the user space. In an aspect, the observer daemon  420 , filter rules  416 , throttling rules  418 , and observer logger  424  may be part of the same component. Implementing the configuration illustrated in  FIG. 5B  may further improve the mobile device efficiency because the observer daemon  420  may update the filter rules without functions calls into the kernel space. 
     At any given time, several applications and several kernel threads may be attempting to store/write information in the ring buffer, which may cause contention issues that hinder scalability. In an aspect, the system&#39;s scalability may be improved via the inclusion of multiple ring buffers, as illustrated in  FIGS. 6A-B . The computing system  600  illustrated in  FIG. 6A  includes all the components described above with reference to  FIG. 5A , but includes multiple ring buffers  430 . The computing system  600  may include a ring buffer for each application, throttle, and kernel thread being monitored by the system. For example, the computing system  600  may include a ring buffer for a kernel thread being monitored by the system, and one or more ring buffers for each application and/or throttle being monitored by the system. Alternatively, the computing system  600  may include a ring buffer for groups of applications, groups of throttles, and/or groups of kernel threads being monitored by the system. The inclusion of multiple ring buffers enables the computing system  600  to avoid contention issues from arising and reduces bottle necks. 
     The computing system  650  illustrated in  FIG. 6B  includes all the components described above with reference to  FIG. 6A , except that the observer daemon  420  is in the user space Implementing the configuration illustrated in  FIG. 6B  may further improve the mobile device efficiency because the observer daemon  420  may update the filter rules without functions calls into the kernel space. 
       FIG. 7A  illustrates logical components and information flows in a computing system  700  implementing an aspect observer daemon  420 . The computing system  700  may include an analyzer component (e.g., the analyzer module  204  illustrated in  FIG. 2 ), a filter rules  416  component, a throttling rules  418  component, multiple ring buffers  430 , a database  702 , a secure buffer  704 , and an observer daemon  420 . The observer daemon  420  may include a ring buffer API  706 , system health monitor  708 , a behavior detector  712 , a database engine  714 , a rules manager  710 , a secure buffer manager  716 , a query processor  720 , a query API  718 , a database API  722 . A logger (not illustrated) may store information in the ring buffers  430 . The observer daemon  420  may extract the information from the ring buffers  430  via the ring buffer API  706 . The behavior detector  712  may receive information from the ring buffer API  706 , and perform correlation and formatting operations on the received data to generate a behavior vector. 
     The generated behavior vector may be sent to the database engine  714  for storing in the database  702 . The database engine  714  may manage all of the specificities of the database implementation (e.g., kind of data structure that is implemented, types of information included in the data structure, etc.). 
     The rules manager  710  may be configured to receive inputs from different components (e.g., system health monitor, behavior detection unit, analyzer, etc.), and update the filter and throttle rules  416 ,  418  based on the received inputs. For example, the rules manager  710  may receive log statistics from the behavior detector  712  and update the filter and throttle rules  416 ,  418  based on the log statistics. 
     The system health monitor  708  may be configured to monitor system resources, and inform the rules manager  710  of the system health. For example, the system health monitor  708  may inform the rules manager  710  about the amount of energy that remains stored in the battery, how much memory is available, whether there are enough resources to perform a detailed observation, etc. The rules manager  710  may use the information received from the system health monitor  708  to update the rules. For example, if the system health monitor  708  indicates that the device battery state is below a certain threshold, the rules manager  710  may update the filter rules  416  such that the system performs more coarse observations in order to reduce power consumption. 
     The query processor  720  may be configured to perform conversions between various API&#39;s, such as from a query API  718  to a database-specific API  722 . 
     The secure buffer  704  may enable kernel space components (e.g., in the un-trusted region) to communicate with the user space components (e.g., in the trusted region). 
     The secure buffer manager  716  may be configured to control the communications that occur via the secure buffer  704 . 
     The database engine  714  may be configured to store the database response to the secure buffer manager  716 , which may perform flow control operations and store the information in the secure buffer  704 . 
     The information generated by the observer daemon  420  may be utilized by an analyzer  204 , which may be implemented in the kernel space, user space, or in a trusted computing base of a system-on-chip (SOC). 
       FIG. 7B  illustrates logical components and information flows in a computing system  750  implementing another aspect observer daemon  420 . The computing system  750  may include an analyzer  204  component, a filter rules  416  component, a throttling rules  418  component, multiple ring buffers  430 , a secure buffer  704 , a secure buffer manager  716 , and an observer daemon  420 . The observer daemon  420  may include a ring buffer API  706 , system health monitor  708 , a behavior detector  712 , a database engine  714 , and a rules manager  710 . A logger (not illustrated) may store information in the ring buffers  430 . The computing system  750  may perform the same operations as the computing system  700  illustrated in  FIG. 7A , except that the secure buffer manager  716  is in the kernel space and may control the data that is sent to an analyzer  204  in the user space. 
       FIG. 8A  illustrates logical components and information flows in a computing system  800  implementing another aspect observer daemon. The computing system  800  illustrated in  FIG. 8A  includes all of the components described above with reference to  FIG. 7A , except for a query processor because the database in this aspect is included as part of the secure buffer. In this configuration, whenever the analyzer issues a query, the query may come directly from the database engine. Similarly, responses to the query may be sent directly from the secure buffer to the analyzer. 
       FIG. 8B  illustrates logical components and information flows in a computing system  800  implementing yet another aspect observer daemon. In the example illustrated in  FIG. 8B , the observer daemon includes a behavior detector  712  and a database engine  714  in the user space, and a secure buffer manager  716 , a rules manager  710 , and a system health monitor  708  in the kernel space. 
     The various aspects provide cross-layer observations on mobile devices encompassing webkit, SDK, NDK, kernel, drivers, and hardware in order to characterize system behavior. The behavior observations may be made in real time. 
     An important feature of the various aspects is that the observer module may perform adaptive observation techniques and control the observation granularity. As discussed above, there are a large number (i.e., thousands) of factors that could contribute to the mobile device&#39;s degradation, and it may not be feasible to monitor/observe all of the different factors that may contribute to the degradation of the device&#39;s performance. To overcome this, the various aspects dynamically identify the relevant behaviors that are to be observed, and dynamically determine the level of detail at which the identified behaviors are to be observed. 
       FIG. 9  illustrates an example method  900  for performing dynamic and adaptive observations in accordance with an aspect. In block  902 , the mobile device processor may perform coarse observations by monitoring/observing a subset of large number factors/behaviors that could contribute to the mobile device&#39;s degradation. In block  903 , the mobile device processor may generate a behavior vector characterizing the coarse observations and/or the mobile device behavior based on the coarse observations. In block  904 , the mobile device processor may identify subsystems, processes, and/or applications associated with the coarse observations that may potentially contribute to the mobile device&#39;s degradation. This may be achieved, for example, by comparing information received from multiple sources with contextual information received from sensors of the mobile device. In block  906 , the mobile device processor may perform behavioral analysis operations based on the coarse observations. In determination block  908 , the mobile device processor may determine whether suspicious behaviors or potential problems can be identified and corrected based on the results of the behavioral analysis. When the mobile device processor determines that the suspicious behaviors or potential problems can be identified and corrected based on the results of the behavioral analysis (i.e., determination block  908 =“Yes”), in block  918 , the processor may initiate a process to correct the behavior and return to block  902  to perform additional coarse observations. 
     When the mobile device processor determines that the suspicious behaviors or potential problems can not be identified and/or corrected based on the results of the behavioral analysis (i.e., determination block  908 =“No”), in determination block  909  the mobile device processor may determine whether there is a likelihood of a problem. In an embodiment, the mobile device processor may determine that there is a likelihood of a problem by computing a probability of the mobile device encountering potential problems and/or engaging in suspicious behaviors, and determining whether the computed probability is greater than a predetermined threshold. When the mobile device processor determines that the computed probability is not greater than the predetermined threshold and/or there is not a likelihood that suspicious behaviors or potential problems exist and/or are detectable (i.e., determination block  909 =“No”), the processor may return to block  902  to perform additional coarse observations. 
     When the mobile device processor determines that there is a likelihood that suspicious behaviors or potential problems exist and/or are detectable (i.e., determination block  909 =“Yes”), in block  910 , the mobile device processor may perform deeper logging/observations or final logging on the identified subsystems, processes or applications. In block  912 , the mobile device processor may perform deeper and more detailed observations on the identified subsystems, processes or applications. In block  914 , the mobile device processor may perform further and/or deeper behavioral analysis based on the deeper and more detailed observations. In determination block  908 , the mobile device processor may again determine whether the suspicious behaviors or potential problems can be identified and corrected based on the results of the deeper behavioral analysis. When the mobile device processor determines that the suspicious behaviors or potential problems can not be identified and corrected based on the results of the deeper behavioral analysis (i.e., determination block  908 =“No”), the processor may repeat the operations in blocks  910 - 914  until the level of detail is fine enough to identify the problem or until it is determined that the problem cannot be identified with additional detail or that no problem exists. 
     When the mobile device processor determines that the suspicious behaviors or potential problems can be identified and corrected based on the results of the deeper behavioral analysis (i.e., determination block  908 =“Yes”), in block  918 , the mobile device processor may perform operations to correct the problem/behavior, and the processor may return to block  902  to perform additional operations. 
     In an aspect, as part of blocks  902 - 918  of method  900 , the mobile device processor may perform real-time behavior analysis of the system&#39;s behaviors to identify suspicious behavior from limited and coarse observations, to dynamically determine the behaviors to observe in greater detail, and to dynamically determine the precise level of detail required for the observations. This enables the mobile device processor to efficiently identify and prevent problems from occurring, without requiring the use of a large amount of processor, memory, or battery resources on the device. 
       FIG. 10  illustrates an example observer method  1000  for performing dynamic and adaptive observations on a mobile device processor in accordance with an aspect. The observer method  1000  may be implemented as part of an observer module in the mobile device&#39;s kernel space, user space, or a combination thereof. In block  1002 , the observer module operating on the processor may receive data, control, and/or context information from various sources, which may include an analyzer unit (e.g., analyzer module  204  described in  FIG. 2 ), application APIs, Driver APIs, kernel threads, user threads, processes, programs, mobile device sensors, etc. In block  1004 , the observer module operating on the processor may adaptively and intelligently filter the received information to generate a smaller subset of the received information. In block  1006 , the observer module operating on the processor may throttle control the filtered information to control/prevent flooding or overloading. In block  1008 , the observer module operating on the processor may perform spatial and temporal correlations to detect/identify high level behaviors that may cause the device to perform at sub-optimal levels. In block  1010 , the observer module operating on the processor may generate a behavior vector that describes the behaviors of particular process, application, or sub-system. In block  1012 , the observer module operating on the processor may store the generated behavior vector in a secure buffer. 
       FIG. 11  illustrates another example method  1100  for perform dynamic and adaptive observations by a mobile device processor in accordance with another aspect. In block  1102 , the mobile device processor may dynamically identify the relevant behaviors that are to be observed on the mobile device. In block  1104 , the mobile device processor may dynamically determine the level of detail at which the identified behaviors are to be observed. In optional block  1106 , the mobile device processor may dynamically adapt to what is being observed. In optional block  1108 , the mobile device processor may dynamically change or update the parameters, factors, behaviors, processes, applications, and/or subsystems that are to be observed. The operations of blocks  1102 - 1108  may be repeated continuously or as is necessary to improve the mobile device performance (e.g., battery power consumption, processing speed, network communication speeds, etc.). 
     The various aspects may be implemented on a variety of mobile computing devices, an example of which is illustrated in  FIG. 12  in the form of a smartphone. A smartphone  1200  may include a processor  1201  coupled to internal memory  1202 , a display  1203 , and to a speaker. Additionally, the smartphone  1200  may include an antenna  1204  for sending and receiving electromagnetic radiation that may be connected to a wireless data link and/or cellular telephone transceiver  1205  coupled to the processor  1201 . Smartphone  1200  typically also include menu selection buttons or rocker switches  1206  for receiving user inputs. 
     A typical smartphone  1200  also includes a sound encoding/decoding (CODEC) circuit  1212 , which digitizes sound received from a microphone into data packets suitable for wireless transmission and decodes received sound data packets to generate analog signals that are provided to the speaker to generate sound. Also, one or more of the processor  1201 , wireless transceiver  1205  and CODEC  1212  may include a digital signal processor (DSP) circuit (not shown separately). 
     Portions of the aspect methods may be accomplished in a client-server architecture with some of the processing occurring in a server, such as maintaining databases of normal operational behaviors, which may be accessed by a mobile device processor while executing the aspect methods. Such aspects may be implemented on any of a variety of commercially available server devices, such as the server  1300  illustrated in  FIG. 13 . Such a server  1300  typically includes a processor  1301  coupled to volatile memory  1302  and a large capacity nonvolatile memory, such as a disk drive  1303 . The server  1300  may also include a floppy disc drive, compact disc (CD) or DVD disc drive  13011  coupled to the processor  1301 . The server  1300  may also include network access ports  1304  coupled to the processor  1301  for establishing data connections with a network  1305 , such as a local area network coupled to other broadcast system computers and servers. 
     The processors  1201 ,  1301  may be any programmable microprocessor, microcomputer or multiple processor chip or chips that can be configured by software instructions (applications) to perform a variety of functions, including the functions of the various aspects described below. In some mobile devices, multiple processors  1201  may be provided, such as one processor dedicated to wireless communication functions and one processor dedicated to running other applications. Typically, software applications may be stored in the internal memory  1202 ,  1302 ,  1303  before they are accessed and loaded into the processor  1201 ,  1301 . The processor  1201 ,  1301  may include internal memory sufficient to store the application software instructions. 
     The foregoing method descriptions and the process flow diagrams are provided merely as illustrative examples and are not intended to require or imply that the steps of the various aspects must be performed in the order presented. As will be appreciated by one of skill in the art the order of steps in the foregoing aspects may be performed in any order. Words such as “thereafter,” “then,” “next,” etc. are not intended to limit the order of the steps; these words are simply used to guide the reader through the description of the methods. Further, any reference to claim elements in the singular, for example, using the articles “a,” “an” or “the” is not to be construed as limiting the element to the singular. 
     The various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the aspects disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention. 
     The hardware used to implement the various illustrative logics, logical blocks, modules, and circuits described in connection with the aspects disclosed herein may be implemented or performed with a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a multiprocessor, but, in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a multiprocessor, a plurality of multiprocessors, one or more multiprocessors in conjunction with a DSP core, or any other such configuration. Alternatively, some steps or methods may be performed by circuitry that is specific to a given function. 
     In one or more exemplary aspects, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored as one or more instructions or code on a non-transitory computer-readable medium or non-transitory processor-readable medium. The steps of a method or algorithm disclosed herein may be embodied in a processor-executable software module which may reside on a non-transitory computer-readable or processor-readable storage medium. Non-transitory computer-readable or processor-readable storage media may be any storage media that may be accessed by a computer or a processor. By way of example but not limitation, such non-transitory computer-readable or processor-readable media may include RAM, ROM, EEPROM, FLASH memory, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that may be used to store desired program code in the form of instructions or data structures and that may be accessed by a computer. Disk and disc, as used herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk, and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of non-transitory computer-readable and processor-readable media. Additionally, the operations of a method or algorithm may reside as one or any combination or set of codes and/or instructions on a non-transitory processor-readable medium and/or computer-readable medium, which may be incorporated into a computer program product. 
     The preceding description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the aspects shown herein but is to be accorded the widest scope consistent with the following claims and the principles and novel features disclosed herein.