Patent Publication Number: US-10333861-B2

Title: Modular cloud computing system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is related to commonly-assigned U.S. patent application Ser. No. 12/872,110, filed on Aug. 31, 2010, now U.S. Pat. No. 9,003,014, which is incorporated by reference herein. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to cloud computing and, more particularly, to techniques for building and managing cloud computing infrastructures. 
     BACKGROUND OF THE INVENTION 
     Cloud computing includes a model for enabling convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction. Cloud computing is often characterized by on-demand self services, broad network access, resource pooling, rapid elasticity, and measured services. 
     For example, cloud computing could include an Infrastructure as a Service (IaaS) model, in which the consumer does not manage or control the underlying cloud infrastructure, but the customer is provided with a capability to provision processing, storage, networks, and other fundamental computing resources where the consumer is able to deploy and run arbitrary software, which can include operating systems and applications. Cloud computing is often used in conjunction with virtualized resources. Virtualization of a resource typically refers to an arrangement in which logical resources are abstracted from physical resources. 
     Cloud computing has received a great deal of attention recently, including the provision of several solutions from prominent information technology (IT) companies. Cloud computing has the potential to overhaul the way IT services and businesses are offered and conducted, thus providing significant cost savings and additional capabilities. 
     Part of the cost savings are due to the scale and level of automation provided in such a model. For example, in order to have cost savings in an Infrastructure as a Service (IaaS) model, one may need at least 20,000 computer servers. Indeed, many established IaaS providers have more than 100,000 servers as part of the cloud. However, building and managing such a large system presents a number of challenges. 
     SUMMARY OF THE INVENTION 
     Principles of the invention provide techniques for building and maintaining a computing infrastructure. While not intended to be limited thereto, such techniques are particularly suitable for application to an cloud computing infrastructure implementing an IaaS model. 
     In an illustrative embodiment, a cloud computing system comprises a first computer coupled to one or more additional computers. Each of the one or more additional computers manages a respective set of one or more virtualized computing resources. The first computer manages the one or more additional computers. 
     Illustrative embodiments of the present invention advantageously provide an infrastructure management methodology for managing large numbers of highly virtualized resources, which can reside in multiple locations, so that they resemble a single large resource that can be used to deliver services. For example, illustrative embodiments advantageously provide a modular approach such that very large scale infrastructures can be built incrementally. Thus, illustrative embodiments can be adapted to future needs to grow to even larger scales, both in size and functionality. Moreover, illustrative embodiments could allow a cloud provider to add additional resources without disrupting the existing available services. 
     These and other objects, features and advantages of the present invention will become apparent from the following detailed description of illustrative embodiments thereof, which is to be read in connection with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows an exemplary embodiment of a cloud computing system in accordance with an illustrative embodiment of the present invention. 
         FIG. 2  shows an exemplary Cloud Operations Center in accordance with an illustrative embodiment of the present invention. 
         FIG. 3  shows an exemplary Point of Deployment system in accordance with an illustrative embodiment of the present invention. 
         FIG. 4  shows an exemplary application-specific cloud computing platform in accordance with an illustrative embodiment of the present invention. 
         FIG. 5  shows a computer system that may be useful in implementing one or more aspects and/or elements of the invention. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     As heretofore discussed, the term “cloud computing” is typically defined as a computing capability that provides an abstraction, or virtualization, between the computing resource and its underlying technical architecture (e.g., servers, storage, networks), enabling convenient, on-demand network access to a shared pool of configurable computing resources that can be rapidly provisioned and released with minimal management effort or service provider interaction. It is to be understood that principles of the invention are not intended to be limited to any particular definition of cloud computing, and that other suitable computing environments are contemplated as being within the scope of the invention. 
       FIG. 1  shows an exemplary embodiment of a cloud computing system  100  in accordance with an illustrative embodiment of the present invention. The exemplary system  100  includes a Cloud Operations Center  120  coupled to one or more data center point-of-deployment (POD) systems numbered  130 - 1 ,  130 - 2  to  130 -N via respective connections  110 - 1 ,  110 - 2  to  110 -N. Typically, the Cloud Operations Center and each POD system will comprise one or more computing systems, as will be discussed in greater detail with reference to  FIG. 5 . 
     More particularly, each POD system is typically responsible for a set of virtualized resources, which may include a data center comprising servers, storage and network equipment. The POD system may include management applications to control this set of virtualized resources in order to support a customer&#39;s IT requirements to run their business. A POD system may include a front end console application. A POD system may be shipped to the customer or it may he hosted at a provider&#39;s data center. 
     Connections  110  may be via the Internet, an intranet and/or an extranet, for example. Alternatively or in addition, one or more of the connections  110  could be a network cable in an embodiment in which one or more of the POD systems  130  is local to the Cloud Operations Center  120 . Generally, performance and availability data is transmitted from each POD system  130  to the Cloud Operations Center  120 , and in turn delegated actions are transmitted from the Cloud Operations Center  120  to the respective POD systems  130 . Examples of these delegated actions include upgrades to software in a POD system, fixes for problems reported in the POD system, and remote installations. 
     The Cloud Operations Center  120  may be clustered for high availability and disaster reliability. The POD systems  130  may also be clustered and/or distributed for performance, availability and reduced latency. The POD systems  130  may be associated with either a service provider or a customer. 
     In contrast to conventional techniques in which management of a computing system is either centralized or distributed, an illustrative embodiment of the present invention provides a separation of end-to-end management responsibilities between the front-end Cloud Operations Center  120  and the respective POD systems  130 . Generally, each POD system  130  is operative to manage a set of virtualized resources. For example, a given POD could provide management of infrastructure, configuration, provisioning, releases, changes, incidents, problems, capacity, service levels, availability, and service desk issues associated with a corresponding set of virtualized resources (e.g., a data center). 
     The Cloud Operations Center  120  is operative to manage the overall cloud computing infrastructure. For example, Cloud Operations Center  120  could provide business support services (e.g., revenue management and customer management), as well as services catalog management. 
     Resource-specific management is handled at the POD system level so that higher-level intelligent orchestration of a requested service is managed at the front-end Cloud Operations Center  120  without requiring server-specific information at the Cloud Operations Center  120 . For example, the Cloud Operations Center  120  requires no knowledge of the specific physical resources associated with each POD. 
     For example, as will be discussed further with reference to  FIG. 2 , Cloud Operations Center  120  handles service requests from users and orchestrates the end-to-end workflow to facilitate that request. For example, customer requirements for a service could be collected through a front end portal of the Cloud Operations Center, then the customer requirements could be sent to an operation layer to provision resources in order to provide the customer with the requested service. 
     A service request refers to a request by a user for a specified service offering, typically in accordance with a service level agreement. Typically, a service request will be based on a service offering selected from a service catalog, which enumerates various service offerings. Examples of service requests include a request for a desktop service, computing infrastructure, or storage service. More generally, a service request will typically entail provisioning of a specified computing infrastructure or platform. One could request a specified number of units of one or more virtualized computing resources (e.g., processor resources, storage resources, or network resources). For example, one may request 50 gigabytes of storage space or 300 megabytes per second of network bandwidth. One could also request access to a specified computing platform or software package, which in turn would require provisioning of virtualized computing resources, such as processor and memory resources. 
     The Cloud Operations Center  120  will also define a set of clearly identified application program interfaces (APIs) that a POD system  130  should support for modularity. As will be discussed further with reference to  FIG. 3 , each POD system  130  represents a self-sufficient and modular unit which is associated with a given set of resources. The POD system  130  performs all resource-level management for its associated resources, thereby hiding these lower-level management specifics from the front-end Cloud Operations Center  120 . In some embodiments, these POD systems may represent diverse application-specific resources. For example, POD system  130 - 1  could be a healthcare POD system similar to that described hereinbelow with reference to  FIG. 4 , while POD system  130 - 2  could be a transportation POD system as will be discussed herein. 
     This modular approach allows one to add or remove POD systems  130  without requiring an overhauling of existing management infrastructures. More particularly, each POD system  130  is designed in a self-contained manner such that additional POD systems  130  can be added to the existing ones without requiring any changes to the existing POD systems. Rather, only the configuration at the Cloud Operation Center  120  needs to be updated to accommodate the additional POD system  130 . Likewise, POD systems can be removed without requiring changes to the remaining POD systems. 
     The Cloud Operations Center  120  keeps track of statistics about each POD system  130  so as to make intelligent decisions about where to dispatch the request to provision or facilitate the requested resources or services. These decisions could be based not only on workload, but also on business level aspects such as cost and QoS. These decisions could also take into account capabilities of the various POD systems, such as industry-specific capabilities associated with one or more of these POD systems, as discussed hereinbelow. The Cloud Operations Center would have sufficient information to map requests into cloud specific operations. This information could, for example, be hierarchical in nature. 
     Once the request is mapped to specific cloud resources and operations, Cloud Operations Center  120  will contact a POD system or a set of POD systems with the request and workflow details to actuate the provisioning of the requested service on the physical resources. This resource-level provisioning is carried out locally by the POD system  130  itself as it has the knowledge of the resources locally available in the POD system. It should be noted that this provisioning may include one POD system operating in a peer-to-peer manner with one or more other POD systems 
       FIG. 2  shows an exemplary architecture for a Cloud Operations Center  200  suitable for use in an embodiment of the present invention. For example, Cloud Operations Center  200  in  FIG. 2  could be a more detailed view of Cloud Operations Center  120  in  FIG. 1 . 
     Cloud Operations Center  200  comprises three main components: Customer Administrator Interface  210 , Cloud Runtime Manager  220 , and Service Provider Administrator Interface  230 . Generally, the Customer Administrator Interface  210  provides functionality to end users (e.g., customers of the service provider) while the Service Provider Administrator Interface  230  provides functionality to an administrator of the cloud computing infrastructure (e.g., the service provider itself). 
     The Customer Administrator Interface  210  comprises Business Support Services module  211 , Portal module  212 , Service Request Catalog module  213 , Provisioning module  214 , and Analytics module  215 . 
     Business Support Services module  211  provides various business support services to users of the cloud computing infrastructure, such as customer management and revenue management. Portal module  212  allows users of the cloud to request cloud services. Examples of these cloud services include creating a new virtual machine (VM) with an image, deleting a resource, or modifying an existing resource. Service Request Catalog module  213  provides intelligence to map an incoming user request to cloud-specific requirements, including the ability to identify which POD system should support this request. Service Request Catalog  213  also provides an interface that allows users/customers to select, size and order the services they want. Service Request Catalog  213  may comprise, for example, a list of available service offerings which the user may select and customize. 
     Provisioning module  214  allows for remote management of the resources so as to facilitate cloud services. For example, Provisioning module  214  works with Service Request Catalog  213  by translating the user&#39;s request for a service—for example, a test environment with specified characteristics—into a specific infrastructure configuration. Provisioning module  214  is also operative to distribute of new and updated software, such as software patches. Analytics module  215  provides analytics and recommendations to support business level analysis, for example, to help minimize risk, maximize value and align IT and business objectives. 
     Cloud Runtime Manager  220  is the core module that provides service monitoring and management for the cloud computing infrastructure. Cloud Runtime Manager  220  is a common resource to the Customer Administrator Interface  210  and the Service Provider Administrator Interface  230 . Once a customer is subscribed to a service and that is deployed and running, both the customer&#39;s IT administrator and the service provider administrator can access the Cloud Runtime Manager  220 , e.g. via web services or programmatic APIs, in order to manage the service. 
     Service Provider Administrator Interface  230  includes Dashboard module  231 , Metering/Monitoring module  232 , Historical Reports module  233 , Event Management module  234 , Alerts module  235 , and Data Warehouse module  236 . Service Provider Administrator Interface  230  also includes a configuration management database (CMDB)  237  and a set of images  238  for problem determination (PD). 
     Dashboard module  231  provides a user interface for the administrator of the cloud computing infrastructure to the other modules described herein. Metering/Monitoring module  232  is operative to obtain performance and availability data from the POD systems  130 . Metering/Module module  232  also tracks actual usage according to defined metrics and translates them into either an internal charge-back transaction or a bill. 
     Generally, the Cloud Operation Center will perform high-level monitoring for the POD systems which it supervises. More particularly, the Cloud Operations Center tracks and keeps data related to the functional capabilities of each POD system as well as high-level POD system state information, including but not limited to, processor utilization and storage capacity. 
     Historical Reports module  233  tracks the performance of the POD systems  130  over time to allow for determination of changes, such as gradual deteriorations in system performance. Event Management module  234  provides for management of both routine and unexpected events. Alerts module  235  generates alerts to the administrator when necessary, such as when an error condition occurs. For example, a breach of pre-established thresholds may automatically trigger the deployment of an additional POD system. 
     Data Warehouse module  236  provides data warehouse operations for management optimization. Element  237  is a CMDB which includes elements representing the configurations of various elements of the cloud computing infrastructure and which may be used in, for example, change management. 
     Element  238  is a PD image repository that stores system checkpoint snapshots of specific POD system software products. These snapshot images are typically labeled as either a correct image or as indicative of a problem type. These snapshot images may include attachments such as, for example, error descriptions and suggested remediation. During the deployment of a POD system, the installation of software is validated against the related images in the PD repository. If the deployment intermediary image matching an image in the PD repository labeled “correct image,” the deployment continues. Otherwise, if a “problem” image is matched, the deployment follows the corresponding attached workflow to solve the problem. Depending on the problem type, the remediation can include an automated restart of deployment, rollout to a previous correct intermediary image, or a suite of manual actions. 
       FIG. 3  shows an exemplary architecture for a POD system  300  suitable for use in an embodiment of the present invention. For example, POD system  300  in  FIG. 2  could be a more detailed view of one the POD systems  130  in  FIG. 1 . 
     POD system  300  generally comprises two major components: Virtualized Infrastructure  310  and Management Interface  320 . Virtualized Infrastructure  310  typically represents resources with which a given POD system is associated. These resources typically comprise components within a data center, such as Servers  311 , Storage  312 , and Network  313 . 
     Management Interface  320 , also known as an Appliance, provides an interface for resource-level management. Data Collection module  321  is responsible for gathering and analyzing performance and availability data regarding the resources associated with the POD system. Detailed monitoring is performed by a POD system with respect to its resources, including the virtualized ones. Configuration and Provisioning module  322  is responsible for managing and altering the configuration of the resources, as well as provisioning of additional resources. Configuration and Provisioning module may utilize a CMDB  324  in a manner similar to that heretofore described with reference to CMDB  237  in  FIG. 2 . Repair Services  323  is responsible for correcting errors and problems with the resources, and may use a PD image repository  325  in a manner similar to that heretofore discussed with reference to PD image repository  238  in  FIG. 2 . 
       FIG. 4  shows an exemplary industry-specific cloud computing application  400  in accordance with an illustrative embodiment of the present invention. More particularly, cloud computing application  400  is targeted toward the healthcare industry. This application begins with patients  410 , whose vital signs or other diagnostic criteria are measured  415  by sensors  420 . The sensors  420  in turn provide data which is collected (acquired)  425  by external data storage  430 . 
     External data storage  430  could include high-end archival storage connected to content. Examples of storage paradigms suitable for use with external data storage  430  include, for example, Scale out File Services (SoFS) and Scale out Network Attached Storage (SoNAS), both of which are commercially available from International Business Machines Corp. of Armonk, N.Y. 
     External data storage  430  could also include a scalable federated database infrastructure operative to provide performance and multi-tenancy for large numbers of clients of varying sizing. An example could be, for example, DB2 data sharing/accelerator. DB2 is a trademark of International Business Machines Corp. of Armonk, N.Y. 
     Cloud computing platform  440  could be a POD system of the type heretofore described with reference to elements  130  in  FIGS. 1 and 300  in  FIG. 3 . Cloud computing platform  440  is operative to host healthcare specific client applications and to enable interaction with the other components of the modular cloud platform shown in  FIG. 1  (e.g., interaction with the Cloud Operations Center for service management). Cloud computing platform  440  preferably provides a highly secure, highly scalable, elastic, on-demand virtual server infrastructure appropriate to serve the workload types specific to healthcare. 
     Cloud computing platform  440  preferably provides functionalities including, for example, one or more of data mining, data warehousing, text processing, and streaming data analytics. Cloud computing platform  440  could include, for example, an Analytics Cloud commercially available from International Business Machines Corp. of Armonk, N.Y. Cloud computing platform  440  preferably includes ETL (Extract-Transform-Load) infrastructure to quickly extract healthcare data in standard formats. 
     In an illustrative embodiment, cloud computing platform  440  includes a number of APIs. In addition to a POD system API heretofore described for modular integration, various healthcare-specific APIs could be provided, such as feedback to sensors and PDA devices. These APIs could be high-availability and highly-specialized mission-critical APIs for developers who need to access and utilize the infrastructures without worrying about implementation details. 
     Other APIs could include social network collaboration APIs to facilitate in finding experts and finding expertise. These could include healthcare-relevant collaboration APIs such as an infrastructure for trusted self-diagnostics applications. Other APIs could include APIs for simulating applications on top of existing data and an API for evidence generation. 
     Cloud computing platform  440  may be operative to provide notifications  443  to medical professionals  450 . Notifications  443  could be provided via modalities such as, for example, electronic mail, world wide web (WWW), short messaging service (SMS), telephone, television, or broadcasting. These notifications  443  could be used by medical professionals  450  to, for example, formulate decisions about the care of patients  410 , such as whether emergency medical services or other first responders would be needed to rescue the patients. 
     Cloud computing platform  440  may also be operative to accept queries  447  from medical professionals  450  and to provide appropriate responses to such queries. Moreover, cloud computing platform could also facilitate collaboration  455  among medical professionals  450  to enhance patient care. 
     Another example of an industry-specific POD system could be one oriented toward the transportation industry. This POD system could be operative to host transportation specific client applications and to enable interaction with the other components of the modular cloud platform shown in  FIG. 1  (e.g., interaction with the Cloud Operations Center for service management). This POD system preferably provides a highly secure, highly scalable, elastic, on-demand virtual server infrastructure appropriate to serve the workload types specific to the transportation industry. 
     The POD system could also include high-end archival storage connected to content. Examples of suitable storage paradigms include, for example, Scale out File Services (SoFS) and Scale out Network Attached Storage (SoNAS), both of which are commercially available from International Business Machines Corp. of Armonk, N.Y. 
     A transportation-specific POD system could also include support for mobility and connectivity in public and private transportation, such as a mobile cloud or cloud roaming. Another possible feature would be a Web 2.0 based ability to communicate missions, goals and activities, as well as receive guidance from the general public and from localized constituencies. It could also be desirable to interface with government bodies such as, for example, the Travel Model Improvement Program and the Freight Analysis Framework, both of which are programs of the Federal Highway Administration. 
     In an illustrative embodiment, cloud computing platform  440  includes a number of APIs. In addition to a POD system API heretofore described for modular integration, various transportation-specific APIs could be provided to process various transportation-specific workloads. These APIs could be high-availability and highly-specialized mission-critical APIs for developers who need to access and utilize the infrastructures without worrying about implementation details. 
     Examples of such workloads include, for example, schedule optimization, route planning, shipment tracking, and delay forecasting. Another exemplary workload is travel demand behavior modeling, which could include simulation of social, demographic, and economic impact on travel demands and could also include financial analytics to produce a sustained competitive advantage. 
     One could also include a collaboration API, for example, to match customers to providers. It may also be desirable to include an API for “what if” analysis in order to assess possible future scenarios and needs, as well as to identify solutions to adapt to these alternative scenarios. Another possible API could include a marketplace API to match transportation services profiles with appropriate analytic services (e.g., analysis of needs or prices), weather forecasting services, urban pattern update requirements, etc. It may also be desirable to include an API for energy-efficiency and environmental sustainability compliance management via sensor data collection and report. 
     As will be appreciated by one skilled in the art, aspects of the present invention may be embodied as a system, method or computer program product. Accordingly, aspects of the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc.) or an embodiment combining software and hardware aspects that may all generally be referred to herein as a “circuit,” “module” or “system.” Such a system may include distinct software modules (for example, a partitioning module executing on a hardware processor). Furthermore, aspects of the present invention may take the form of a computer program product embodied in one or more computer readable medium(s) having computer readable program code embodied thereon. 
     Additionally, the techniques as heretofore described can be implemented via a computer program product that can include computer useable program code that is stored in a computer readable storage medium in a data processing system, and wherein the computer useable program code was downloaded over a network from a remote data processing system. Also, in one or more embodiments of the invention, the computer program product can include computer useable program code that is stored in a computer readable storage medium in a server data processing system, and wherein the computer useable program code are downloaded over a network to a remote data processing system for use in a computer readable storage medium with the remote system. 
     A variety of techniques, utilizing dedicated hardware, general purpose processors, firmware, software, or a combination of the foregoing may be employed to implement the present invention or components thereof. One or more embodiments of the invention, or elements thereof, can be implemented in the form of a computer product including a computer usable medium with computer usable program code for performing the method steps indicated. Furthermore, one or more embodiments of the invention, or elements thereof, can be implemented in the form of an apparatus including a memory and at least one processor that is coupled to the memory and operative to perform exemplary method steps. 
     One or more embodiments can make use of software running on a general purpose computer or workstation. With reference to  FIG. 5 , such an implementation employs, for example, a processor  510 , a memory  520 , and an input/output interface formed, for example, by a display  530  and a keyboard  540 . The term “processor” as used herein is intended to include any processing device, such as, for example, one that includes a CPU (central processing unit) and/or other forms of processing circuitry. Further, the term “processor” may refer to more than one individual processor. The term “memory” is intended to include memory associated with a processor or CPU, such as, for example, RAM (random access memory), ROM (read only memory), a fixed memory device (for example, hard drive), a removable memory device (for example, diskette), a flash memory and the like. In addition, the phrase “input/output interface” as used herein, is intended to include, for example, one or more mechanisms for inputting data to the processing unit (for example, keyboard or mouse), and one or more mechanisms for providing results associated with the processing unit (for example, display or printer). The processor  510 , memory  520 , and input/output interface such as display  530  and keyboard  540  can be interconnected, for example, via bus  550  as part of a data processing unit  560 . Suitable interconnections, for example via bus  550 , can also be provided to a network interface  570 , such as a network card, which can be provided to interface with a computer network, and to a media interface  580 , such as a diskette or CD-ROM drive, which can be provided to interface with media  590 . 
     Accordingly, computer software including instructions or code for performing the methodologies of the invention, as described herein, may be stored in one or more of the associated memory devices (for example, ROM, fixed or removable memory) and, when ready to be utilized, loaded in part or in whole (for example, into RAM) and executed by a CPU. Such software could include, but is not limited to, firmware, resident software, microcode, and the like. 
     Furthermore, the invention can take the form of a computer program product accessible from a computer-usable or computer-readable medium (for example, media  590 ) providing program code for use by or in connection with a computer or any instruction execution system. For the purposes of this description, a computer usable or computer readable medium can be any apparatus for use by or in connection with the instruction execution system, apparatus, or device. The medium can store program code to execute one or more method steps set forth herein. 
     A data processing system suitable for storing and/or executing program code can include at least one processor  510  coupled directly or indirectly to memory elements  520  through a system bus  550 . The memory elements can include local memory employed during actual execution of the program code, bulk storage, and cache memories which provide temporary storage of at least some program code in order to reduce the number of times code must be retrieved from bulk storage during execution. 
     Input/output or I/O devices (including but not limited to keyboard  540 , display  530 , pointing device, and the like) can be coupled to the system either directly (such as via bus  550 ) or through intervening I/O controllers (omitted for clarity). 
     Network adapters such as network interface  570  may also be coupled to the system to enable the data processing system to become coupled to other data processing systems or remote printers or storage devices through intervening private or public networks. Modems, cable modem and Ethernet cards are just a few of the currently available types of network adapters. 
     As used herein, including the claims, a “server” includes a physical data processing system (for example, system  560  as shown in  FIG. 5 ) running a server program. It will be understood that such a physical server may or may not include a display and keyboard. 
     Embodiments of the invention have been described herein with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks. 
     These computer program instructions may also be stored in a tangible computer-readable storage medium that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable medium produce an article of manufacture including instruction means which implement the function/act specified in the flowchart and/or block diagram block or blocks. The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks. 
     Any combination of one or more computer readable medium(s) may be utilized. The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A computer readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of the computer readable storage medium would include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer readable storage medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. 
     A computer readable signal medium may include a propagated data signal with computer readable program code embodied therein, for example, in baseband or as part of a carrier wave. Such a propagated signal may take any of a variety of forms, including, but not limited to, electro-magnetic, optical, or any suitable combination thereof. A computer readable signal medium may be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device. 
     Program code embodied on a computer readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing. 
     The flowchart and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems that perform the specified functions or acts, or combinations of special purpose hardware and computer instructions. 
     Furthermore, it should be noted that any of the methods described herein can include an additional step of providing a system comprising distinct software modules embodied on a tangible computer readable storage medium. The method steps can then be carried out using the distinct software modules and/or sub-modules of the system, as described above, executing on a hardware processor. Further, a computer program product can include a tangible computer-readable storage medium with code adapted to be executed to carry out one or more method steps described herein, including the provision of the system with the distinct software modules. 
     In any case, it should be understood that the components illustrated herein may be implemented in various forms of hardware, software, or combinations thereof; for example, application specific integrated circuit(s) (ASICs), functional circuitry, one or more appropriately programmed general purpose digital computers with associated memory, and the like. Given the teachings of the invention provided herein, one of ordinary skill in the related art will be able to contemplate other implementations of the components of the invention. 
     It will be appreciated and should be understood that the exemplary embodiments of the invention described above can be implemented in a number of different fashions. Given the teachings of the invention provided herein, one of ordinary skill in the related art will be able to contemplate other implementations of the invention. Indeed, although illustrative embodiments of the present invention have been described herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various other changes and modifications may be made by one skilled in the art without departing from the scope or spirit of the invention.