Patent Publication Number: US-9838449-B2

Title: Local streaming proxy server

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 14/748,188, filed on Jun. 23, 2015, which is a continuation of U.S. patent application Ser. No. 14/520,601, filed on Oct. 22, 2014, now U.S. Pat. No. 9,083,774, which is a continuation of U.S. patent application Ser. No. 14/211,196, filed on Mar. 14, 2014, now U.S. Pat. No. 8,874,699, which is a continuation of U.S. patent application Ser. No. 13/536,585, filed on Jun. 28, 2012, now U.S. Pat. No. 8,676,938, which claims priority to U.S. Provisional No. 61/502,258, filed on Jun. 28, 2011, all of which are incorporated by reference. 
    
    
     BACKGROUND 
     An area of ongoing research and development is application delivery to computing devices. One aspect of application delivery is speed. Current application delivery platforms enable a device to download an application, which takes as much time as is required to accomplish the download, followed by an installation time. When the application is delivered from a relatively remote source, additional issues arise. 
     Another aspect of application delivery is security. Not all application delivery platforms offer the same amount of security in application delivery, piracy prevention, or the like. Other aspects of application delivery include network utilization, reduced power requirements for devices to which applications are delivered (and potentially for devices from which applications are delivered), and application and operating system performance consistency. 
     Downloading and installing an application is a simple way to obtain performance consistency, but this technique has other shortcomings. For example, there is often no effective piracy prevention in the delivery mechanism (though there can be piracy prevention through other techniques). This technique also means the device onto which the application is delivered must be capable of storing the application and running the application with sufficient speed such that users are not bothered by the performance. Network utilization is also limited to controlling the download, which essentially only impacts download times for a device without necessarily enabling load balancing to improve performance of all devices. These weaknesses with standard download/install have led to continuing research into virtual application delivery solutions. 
     SUMMARY 
     The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools, and methods that are meant to be exemplary and illustrative, not necessarily limiting in scope. In various embodiments, one or more of the above-described problems have been addressed, while other embodiments are directed to other improvements. 
     The proxy can create a virtual image of storage media, which allows cloud operators to rapidly deliver applications, or deliver any operating system remotely, while providing better security, network utilization, low power requirements, and consistent performance for streamed applications and operating systems. A station using its WiFi/LAN provides QoS guarantees (or priority) for application streaming network communications to create a consistent user experience regardless of other application bandwidth utilization. “HTTP demand paging” is also possible. 
     A proof of concept running on a wireless netbook delivering virtual machines using techniques described in this paper has been impressive—for VM running WinTPC (a stripped Win? OS), startup times very close to machines with the OS natively installed have been achieved. 
     The foregoing examples of the related art and limitations related therewith are intended to be illustrative and not exclusive. For example, wireless clients may use different protocols other than WiFi (or IEEE 802.11), potentially including protocols that have not yet been developed. However, problems associated with performance may persist. Other limitations of the relevant art will become apparent to those of skill in the art upon a reading of the specification and a study of the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  depicts a diagram of an example of an application streaming system with a local proxy. 
         FIG. 2  depicts a diagram of an example of an application streaming system with a local proxy. 
         FIG. 3  depicts a flowchart of an example of a method for local application streaming. 
         FIG. 4  depicts a flowchart of an example of a method of local proxy application streaming. 
         FIG. 5  depicts a diagram of an example of a system with a local proxy smartphone. 
         FIG. 6  depicts a diagram of an example of a system for an application streaming system. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  depicts a diagram  100  of an example of an application streaming system with a local proxy. In the example of  FIG. 1 , the diagram  100  includes a network  102 , an application streaming server  104 , a local application streaming proxy  106 , a computer-readable medium  108 , and clients  110 - 1  to  110 -N (collectively referred to as clients  110 ). 
     In the example of  FIG. 1 , the network  102  may be practically any type of communications network, such as the Internet or an infrastructure network. The term “Internet” as used in this paper refers to a network of networks that use certain protocols, such as the TCP/IP protocol, and possibly other protocols, such as the hypertext transfer protocol (HTTP) for hypertext markup language (HTML) documents that make up the World Wide Web (“the web”). More generally, the network  102  can include, for example, a wide area network (WAN), metropolitan area network (MAN), campus area network (CAN), or local area network (LAN), but the network  102  could at least theoretically be of any size or characterized in some other fashion. Networks can include enterprise private networks and virtual private networks (collectively, private networks). As the name suggests, private networks are under the control of a single entity. Private networks can include a head office and optional regional offices (collectively, offices). Many offices enable remote users to connect to the private network offices via some other network, such as the Internet. The example of  FIG. 1  is intended to illustrate a network  102  that may or may not include more than one private network. 
     In the example of  FIG. 1 , the application streaming server  104  is coupled to the network  102 . In the example of  FIG. 1 , the application streaming server  104  provides administrative and license management in coordination with a local application streaming proxy server. In a specific implementation, the application streaming server  104  is implemented as a NUMECENT™/APPROXY™ portal or gateway. As such, the application streaming server  104  can in alternative implementations be referred to as an “application streaming portal” or an “application streaming gateway.” 
     The application streaming server  104 , and more generally any device connected to a network, can be referred to as “on” the network. For illustrative purposes, the application streaming server  104  is described in this example as serving content. Accordingly, in this example, the application streaming server  104  can be referred to as a content server. A web server, which is one type of content server, is typically at least one computer system that operates as a server computer system and is configured to operate with the protocols of the World Wide Web and is coupled to the Internet. Unless context dictates otherwise, a server as used in this paper includes at least a portion of a computer system running server software. 
     A computer system, as used in this paper, is intended to be construed broadly. In general, a computer system will include a processor, memory, non-volatile storage, and an interface. A typical computer system will usually include at least a processor, memory, and a device (e.g., a bus) coupling the memory to the processor. 
     The processor can be, for example, a general-purpose central processing unit (CPU), such as a microprocessor, or a special-purpose processor, such as a microcontroller. 
     The memory can include, by way of example but not limitation, random access memory (RAM), such as dynamic RAM (DRAM) and static RAM (SRAM). The memory can be local, remote, or distributed. As used in this paper, the term “computer-readable storage medium” is intended to include only physical media, such as memory. As used in this paper, a computer-readable medium is intended to include all mediums that are statutory (e.g., in the United States, under 35 U.S.C. 101), and to specifically exclude all mediums that are non-statutory in nature to the extent that the exclusion is necessary for a claim that includes the computer-readable medium to be valid. Known statutory computer-readable mediums include hardware (e.g., registers, random access memory (RAM), non-volatile (NV) storage, to name a few), but may or may not be limited to hardware. 
     The bus can also couple the processor to the non-volatile storage. The non-volatile storage is often a magnetic floppy or hard disk, a magnetic-optical disk, an optical disk, a read-only memory (ROM), such as a CD-ROM, EPROM, or EEPROM, a magnetic or optical card, or another form of storage for large amounts of data. Some of this data is often written, by a direct memory access process, into memory during execution of software on the computer system. The non-volatile storage can be local, remote, or distributed. The non-volatile storage is optional because systems can be created with all applicable data available in memory. 
     Software is typically stored in the non-volatile storage. Indeed, for large programs, it may not even be possible to store the entire program in the memory. Nevertheless, it should be understood that for software to run, if necessary, it is moved to a computer-readable location appropriate for processing, and for illustrative purposes, that location is referred to as the memory in this paper. Even when software is moved to the memory for execution, the processor will typically make use of hardware registers to store values associated with the software, and local cache that, ideally, serves to speed up execution. As used herein, a software program is assumed to be stored at any known or convenient location (from non-volatile storage to hardware registers) when the software program is referred to as “implemented in a computer-readable storage medium.” A processor is considered to be “configured to execute a program” when at least one value associated with the program is stored in a register readable by the processor. 
     In one example of operation, a computer system can be controlled by operating system software, which is a software program that includes a file management system, such as a disk operating system. One example of operating system software with associated file management system software is the family of operating systems known as Windows® from Microsoft Corporation of Redmond, Wash., and their associated file management systems. Another example of operating system software with its associated file management system software is the Linux operating system and its associated file management system. The file management system is typically stored in the non-volatile storage and causes the processor to execute the various acts required by the operating system to input and output data and to store data in the memory, including storing files on the non-volatile storage. 
     The bus can also couple the processor to the interface. The interface can include one or more input and/or output (I/O) devices. The I/O devices can include, by way of example but not limitation, a keyboard, a mouse or other pointing device, disk drives, printers, a scanner, and other I/O devices, including a display device. The display device can include, by way of example but not limitation, a cathode ray tube (CRT), liquid crystal display (LCD), or some other applicable known or convenient display device. The interface can include one or more of a modem or network interface. It will be appreciated that a modem or network interface can be considered to be part of the computer system. The interface can include an analog modem, isdn modem, cable modem, token ring interface, satellite transmission interface (e.g. “direct PC”), or other interfaces for coupling a computer system to other computer systems. Interfaces enable computer systems and other devices to be coupled together in a network. 
     In the example of  FIG. 1 , the application streaming server  104  includes a network interface  112 , a demand paging engine  114 , a composite master image datastore  116 , an access control token definition engine  118 , and a streamified application datastore  119 . The application streaming server  104  can communicate using a network transport and message service (NTS). The network interface  112  can be implemented as an applicable known or convenient interface sufficient to enable the application streaming server  104  communication with or through the network  102 . 
     The demand paging engine  114  is responsible for streaming an application using a demand paging technique. As used in this paper, an engine includes a dedicated or shared processor and, typically, firmware or software modules that are executed by the processor. Depending upon implementation-specific or other considerations, an engine can be centralized or its functionality distributed. An engine can include special purpose hardware, firmware, or software embodied in a computer-readable medium for execution by the processor. As used in this paper, a computer-readable medium is intended to include all mediums that are statutory (e.g., in the United States, under 35 U.S.C. 101), and to specifically exclude all mediums that are non-statutory in nature to the extent that the exclusion is necessary for a claim that includes the computer-readable medium to be valid. Known statutory computer-readable mediums include hardware (e.g., registers, random access memory (RAM), non-volatile (NV) storage, to name a few), but may or may not be limited to hardware. 
     The composite master image datastore  116  includes one or more images that can be provided to the clients  110 . The images include snapshots of applications on top of a machine. Thus, the images can be referred to as “application snapshots.” Application snapshots can be made portable across at least some machines (or OSs if the application is sufficiently neutral, such as Java). A snapshot engine (not shown) can take an initial snapshot of an environment before the application is run (unless the snapshot engine has access to an installation file from which an application install can be deconstructed, such as Android) then after installation in the cloud. The resultant package, the application snapshot, can be invoked on a device or in the cloud using the environment snapshot, if needed. 
     A datastore can be implemented, for example, as software embodied in a physical computer-readable medium on a general- or specific-purpose machine, in firmware, in hardware, in a combination thereof, or in an applicable known or convenient device or system. Datastores in this paper are intended to include any organization of data, including tables, comma-separated values (CSV) files, traditional databases (e.g., SQL), or other applicable known or convenient organizational formats. Datastore-associated components, such as database interfaces, can be considered “part of” a datastore, part of some other system component, or a combination thereof, though the physical location and other characteristics of datastore-associated components is not critical for an understanding of the techniques described in this paper. 
     Datastores can include data structures. As used in this paper, a data structure is associated with a particular way of storing and organizing data in a computer so that it can be used efficiently within a given context. Data structures are generally based on the ability of a computer to fetch and store data at any place in its memory, specified by an address, a bit string that can be itself stored in memory and manipulated by the program. Thus some data structures are based on computing the addresses of data items with arithmetic operations; while other data structures are based on storing addresses of data items within the structure itself. Many data structures use both principles, sometimes combined in non-trivial ways. The implementation of a data structure usually entails writing a set of procedures that create and manipulate instances of that structure. 
     The demand paging engine  114  can deliver partial or full images from the composite master image datastore  116  to the local application streaming proxy  106 . 
     The access control token definition engine  118  creates tokens to define access policies of the clients  110 . The access control tokens are passed to the local application streaming proxy  106  and clients  110 . In a specific implementation, the access control includes digital rights management (DRM) functionality. 
     The streamified application datastore  119  is coupled to the demand paging engine  114 . A streamified application is broken into portions (e.g., blocks, chunks, pages, etc.) that are streamed on a per-portion basis to an application streaming client. 
     The local application streaming proxy  106  is controlled by the application streaming server  104 , which acts as a master server, running remotely (e.g. in the Cloud). The application streaming server  104  may or may not bypass the local application streaming proxy  106 , but in any case delivers software applications from the application streaming server  104 , which can be referred to as a central server relative to a plurality of proxies, if applicable, and to a target machine of the clients  110 , where the software is executed. In certain implementations, the local application streaming proxy  106  is expected to serve one target at a time. The software application delivered from the master server could be partials (e.g. prefetch/jumpstart) to help reduce a storage footprint on the local application streaming proxy  106  and/or the clients  110 , and the rest could be streamed from the master through the local application streaming proxy  106 . 
     In a specific implementation, the local application streaming proxy  106  is part of a JUKEBOX SERVER™ system. The local application streaming proxy  106  can be implemented on a smartphone (e.g., an Android) so that applications can be streamed from the smartphone proxy to the clients  110 . The smartphone can stream using local WiFi or other applicable technology. In a specific implementation, the smartphone can serve  5  or  6  users, but the number of users that can be supported will vary depending upon many factors. Advantageously, the smartphone is an intelligent or active (managed) proxy to aid in unreliable QoS (e.g. intermittent) and offline connectivity environments. The device can be referred to as a local cloud device. It is not necessary for the implementation to be a smartphone to obtain this advantage (e.g. router, access point, proxy, etc. are also applicable). So the smartphone can more generally be referred to as a station in IEEE 802.11 parlance. 
     In a specific implementation, it is possible to accomplish streaming virtual machines or machine images onto the proxy (full or partial) and then onto the target, which could also be accomplished with the above approach, but with some different details and requirements (though these could be combinable). This allows laptops (or desktops/tablets) to launch directly off of the proxy device, reducing space requirements on the target, which improves security. In a specific implementation, writes are imaged back up to the server. 
     Advantageously, the local application streaming proxy  106  can create a virtual image of storage media, which allows cloud operators to rapidly deliver applications, or deliver any operating system remotely, while providing better security, network utilization, low power requirements, and consistent performance for streamed applications and operating systems. A station using its WiFi/LAN provides QoS guarantees (or priority) for application streaming network communications to create a consistent user experience regardless of other application bandwidth utilization. “HTTP demand paging” is also possible. 
     In the example of  FIG. 1 , the local application streaming proxy  106  includes a network interface  120 , a machine image datastore  122 , an access control engine  124 , and a medium interface  126 . The network interface  120  can be implemented as an applicable known or convenient interface sufficient to enable the local application streaming proxy  106  communication with or through the network  102 . 
     The machine image datastore  122  includes one or more application snapshots. The application snapshots are a subset of the images stored in the composite master image datastore  116  of the application streaming server  104 . In an implementation that includes multiple local application streaming proxies, different proxies may or may not have different subsets of the images of the composite master image datastore  116 . The differences can depend, for example, upon the needs of clients locally served by a particular proxy. 
     The access control engine  124  enforces access control policy at the clients  110  and, potentially, at the local application streaming proxy  106 . The access control engine  124  provides one or more images from the machine image datastore  122  to the clients  110 . In a specific implementation, the access control engine  124  uses DRM to authenticate and regulate access of a target machine of the clients  110 . The access control engine  124  may prevent provisioning of a snapshot to a client if the client is in violation of access control policy. In a specific implementation, the access control engine  124  can instruct a client to wipe its cache or delete relevant portions of memory. Access control policy is defined by access control tokens that the local application streaming proxy  106  received from the application streaming server  104 . Advantageously, the access control engine  124  can ensure access control policies are enforced at the clients  110  even if the local application streaming proxy  106  is offline (i.e., not on the network  102 ). This facilitates the use of “offlining” in instances where it would not otherwise be possible. 
     The medium interface  126  is coupled to the computer-readable medium  108 . The depiction of the medium interface  126  and the network interface  120  is intended to illustrate one connection is to the application streaming server  104  and another connection is to the clients  110 . Where the computer-readable medium  108  is implemented as a LAN, the medium interface  126  can be referred to as a LAN interface  126 . Where the computer-readable medium  108  is implemented as a wireless LAN (WLAN), the medium interface  126  can be referred to as a wireless network interface or a radio. Where the computer-readable medium  108  is on a device on which the local application streaming proxy  106  and one or more of the clients  110  also reside, the medium interface  126  can include a bus interface or some other interface (that may or may not normally be referred to as an “interface”) that ultimately enables the local application streaming proxy  106  communication on or through the computer-readable medium  108 . 
     The streamified application datastore  127  is coupled to the access control engine  124 . A streamified application is broken into portions (e.g., blocks, chunks, pages, etc.) that are streamed on a per-portion basis to an application streaming client. 
     The computer-readable medium  108  is coupled to the local application streaming proxy  106  and the clients  110 . The computer-readable medium  108  can be implemented as a wired or wireless medium. In a wireless communications context, the local application streaming proxy  106  and the clients  110  can be referred to as stations. A station, as used in this paper, may be referred to as a device with a media access control (MAC) address and a physical layer (PHY) interface to a wireless medium that complies with the IEEE 802.11 standard. Thus, for example, the stations and a wireless access point (WAP) with which the stations associate can be referred to as stations, if applicable. IEEE 802.11a-1999, IEEE 802.11b-1999, IEEE 802.11g-2003, IEEE 802.11-2007, and IEEE 802.11n TGn Draft 8.0 (2009) are incorporated by reference. As used in this paper, a system that is 802.11 standards-compatible or 802.11 standards-compliant complies with at least some of one or more of the incorporated documents&#39; requirements and/or recommendations, or requirements and/or recommendations from earlier drafts of the documents, and includes Wi-Fi systems. Wi-Fi is a non-technical description that is generally correlated with the IEEE 802.11 standards, as well as Wi-Fi Protected Access (WPA) and WPA2 security standards, and the Extensible Authentication Protocol (EAP) standard. In alternative embodiments, a station may comply with a different standard than Wi-Fi or IEEE 802.11, may be referred to as something other than a “station,” and may have different interfaces to a wireless or other medium. 
     The clients  110  receive streamed application data from the application streaming server  104 . Streamed application data is a form of content. Thus, in this example, the server-client relationship between the application streaming server  104  and the clients  110  is that of content server to content consumer. Also, the clients  110  can be referred to as “content receiving clients” or “application streaming clients.” A device that includes a client  110 - 1  can also include a client of some other server or include a server for some other client. For example, in a wireless context, the device can include a wireless client and be associated with a wireless network, such as a WLAN. 
     In a specific implementation, the local application streaming proxy  106  is implemented on a device that is different from devices on which the clients  110  are implemented. Alternatively, the local application streaming proxy  106  and one or more of the clients  110  are implemented on the same device. 
       FIG. 2  depicts a diagram  200  of an example of an application streaming system with a local proxy. In the example of  FIG. 2 , the diagram  200  includes a network  202 , an application streaming server  204 , a local application streaming proxy  206 , a computer-readable medium  208 , and clients  210 - 1  to  210 -N (collectively referred to as clients  210 ). The network  202 , application streaming server  204 , local application streaming proxy  206 , and computer-readable medium  208  can be implemented as described for the network  102 , the application streaming server  104 , the local application streaming proxy  106 , and the computer-readable medium  108  of  FIG. 1 , though not necessarily exactly as described. 
     The local application streaming proxy  206  includes a network interface  220  coupled to the network  202 , a machine image datastore  222  coupled to the network interface, an access control engine  224  coupled to the machine image datastore  222 , a medium interface  226  coupled to the access control engine  224  and the computer-readable medium  208 , and a streamified application datastore  227  coupled to the access control engine  224 . 
     In the example of  FIG. 2 , the application streaming client  210 - 1  includes a medium interface  228 , a download engine  230 , an application streaming player  232 , a cache management engine  234 , a cache  236 , and a bootstrap loader  238 . The application streaming client  210 - 1  can also include a file system driver (FSD) (not shown). The medium interface  228  can be implemented as an applicable known or convenient interface sufficient to enable the client  210 - 1  communication with or through the computer-readable medium  208 . 
     The download engine  230  obtains an application snapshot from the application streaming server  204  or the local application streaming proxy  206 . The application snapshot informs the application streaming client  210 - 1  of what characteristics the application would have if installed on the application streaming client  210 - 1 . This enables the applications streaming client  210 - 1  to act as if the applicable application is installed on the application streaming client  210 - 1  even when it is not. The download engine  230  can also obtain jumpstart partials, which include portions of the application that have been determined to cause potential delay if not downloaded before the start of the streamed application (e.g., portions of the application that are inevitably run during an early part of an application&#39;s execution). The download engine  230  can include a content prefetcher that obtains portions of the streamed application in anticipation of needing the portions soon, or at least at some point in the future. The sensitivity of the content prefetcher (i.e., the probability that a portion of an application will be considered “likely” to be used soon or at least at some point in the future) can be configurable or unconfigurable, depending upon the implementation. 
     The application streaming player  232  runs the streamed application as if it were installed on the application streaming client  210 - 1 . As used in this paper, installed is intended to mean “fully installed” such that executing the streamed application would not result in a system crash if an uninstalled portion of the application were accessed. As used in this paper, an application is intended to mean an executable (not simply data) program with at least one branch instruction. Due to the implementation of the downloaded application snapshot, the application streaming player  232  “thinks” that the application is installed on the machine. In addition, the application streaming player  232  can capture requests for portions of the streamed application (or data) that is not locally available and instruct the download engine  230  to obtain the portions of the streamed application that are not locally available. 
     In a specific implementation, the application streaming player  232  implements an access control policy from the application streaming server  204  and/or the local application streaming proxy  206 . The application streaming player  232  can enforce, e.g., DRM policies. The application streaming player  232  can use DRM when communicating with the proxy or master. 
     The cache management engine  234  manages the cache  236  (which can be considered a datastore) to enable the application streaming player  232  to satisfy requests using portions of the streamed application in the cache  236 . The download engine  230  can provide additional portions of the streamed application to the cache  236  over time. The cache management engine  234  can clear portions of the cache  236  in accordance with a cache management protocol (e.g., older entries can be deleted before newer entries). 
     The bootstrap loader  238  boots directly off of the local application streaming proxy  106 . One way to view this is that the proxy (e.g., smartphone) comes with an intelligent, secured, cloud tethered virtual hard drive that you can bind to a computing device. In a specific implementation, the bootstrap loader  238  implements a preboot execution environment (PXE). The increasing popularity of client-side hypervisors will make this an even stronger use case. 
       FIG. 3  depicts a flowchart  300  of an example of a method for local application streaming. In the example of  FIG. 3 , the flowchart  300  starts at module  302  with taking a pre-installation environment snapshot. Taking a pre-installation snapshot is optional in the sense that some environments include an adequate installation log that enables an engine to determine what changes an application made to a system when the application was installed. 
     In the example of  FIG. 3 , the flowchart  300  continues to module  304  with fully installing the application. Due to the nature of streaming, it is important to ensure that an application streaming content consumer not crash when a request for a file resource of the application is not present. Accordingly, a full installation is needed to create the application snapshot, even if the application is never fully streamed in its entirety. 
     In the example of  FIG. 3 , the flowchart  300  continues to module  306  with taking a post-installation environment snapshot. Again, taking the post-installation snapshot is optional in the sense that some environments include an adequate installation log. 
     In the example of  FIG. 3 , the flowchart  300  continues to module  308  with determining application snapshot based on changes to the environment. If there is an adequate installation file, the application snapshot can be determined from the file. If not, the application snapshot can be determined at least in part from the differences in a pre- and post-installation environment snapshot. In some cases, additional processing may be required to create an application snapshot due to deficiencies in some computer self-monitoring engines. 
     In the example of  FIG. 3 , the flowchart  300  continues to module  310  with providing application snapshot to application streaming server. The application streaming server can provide the application snapshot to a client with a compatible configuration to enable the client to request file resources in the normal course of the on-client (local) execution of a streaming application even if the file resources are not on the client. 
       FIG. 4  depicts a flowchart  400  of an example of a method of local proxy application streaming. In the example of  FIG. 4 , the flowchart  400  starts at module  402  with obtaining an application snapshot at an application streaming proxy server. The application snapshot could be received from an application snapshot server, which can conceptually be considered part of a master application streaming server. In some implementations, the application snapshot could be provided through some other input device, such as removable storage. 
     In the example of  FIG. 4 , the flowchart  400  continues to module  404  with obtaining an access control token at the application streaming proxy server. The access control token can be received from an access control token server, which can conceptually be considered part of the master application streaming server. In some implementations, the access control token could be provided through some other input device, such as removable storage and/or defined or modified at the local application streaming proxy. Depending upon the implementation, it may be undesirable to allow the proxy to define or modify access control tokens due to security, DRM, or other risk concerns. 
     In the example of  FIG. 4 , the flowchart  400  continues to module  406  with obtaining portions of a streamified application at the application streaming proxy. A streamified application is broken into portions (e.g., blocks, chunks, pages, etc.) that are streamed on a per-portion basis to an application streaming client. A master application streaming server can provide a subset of the portions to the application streaming proxy. The subset can include one or more jumpstart portions, one or more prefetch portions, and/or one or more of the other portions of the streamified application. In a specific implementation, the application streaming proxy can be allowed to store all of the portions of a streamified application. In another specific implementation, the application streaming proxy can be prevented from storing all of the portions of the streamified application to make piracy more difficult (by not making all portions of the streamified application readily available in a single location), to conserve resources at the proxy, or for other reasons. In a specific implementation, the jumpstart portion(s) of the streamified application is not stored at the proxy. 
     In the example of  FIG. 4 , the flowchart  400  continues to module  408  with providing the application snapshot to a local application streaming client. Application snapshots may or may not be appropriate for all operating systems, but can typically be appropriate for a plurality of computers without modification. The proxy may or may not need to determine the characteristics of the client before providing the application snapshot to ensure a proper application snapshot is provided. The local application streaming client can use the application snapshot to request file resources identifiable from the application snapshot that are not presently on the client (an application streaming player will request the applicable streamified portions to satisfy the requests). 
     In the example of  FIG. 4 , the flowchart  400  continues to module  410  with providing portions of the streamified application to the local application streaming client in accordance with the access control token. The access control token is associated with an access control policy, such as DRM, that is set at a server. An advantage of using the access control token at the proxy is that the proxy can be unconnected from the server (operating in offline mode) and still enforce access control policy. 
       FIG. 5  depicts a diagram  500  of an example of a system with a local proxy smartphone. In the example of  FIG. 5 , the system includes a portal  502 , a smartphone proxy  504  and an end-user device  506 . In operation, the portal  502  sends portions of a streamified application to the smartphone proxy  504 . In a specific implementation, the portal  502  can perform administrative and license management with the smartphone proxy  504  over a 3G/4G or WiFi network. Advantageously, the smartphone becomes a microappliance providing a user&#39;s favorite apps in-pocket, with the security smartphones offer. In a specific implementation, the smartphone proxy  504  can perform application streaming to the end user device  506  over a local WiFi channel. Advantageously, using local WiFi provides control over transmissions, which can improve performance not only at the end-user device  506 , but also for other users on the WiFi network. The end-user device  506  receives streamed applications (games or enterprise) from the smartphone proxy  504 . No installation is required, the applications can be provided on demand, and the end-user device  506  has the security end-user computer systems offer. 
       FIG. 6  depicts a diagram  600  of an example of a system for an application streaming system. In the example of  FIG. 6 , the system includes a network and transport message structure (NTS)  602 , a cache manager (CCM)  604 , and a content fetcher system (CFS)  606 . The system can also include a file system directory (FSD) and bootstrapping engine (not shown). In a specific implementation, for an application streaming client to receive streamed applications, the client needs a storage device and interface, a network HTTP stack, tread support, and encryption &amp; compression libraries. In the example of  FIG. 6 , the NTS  602  and the CFS  606  communicate requests, updates, responses, and errors with one another. 
     In the example of  FIG. 6 , the CCM  604  includes a cache files datastore  610 . Portions of a streamified application can be stored in the cache files datastore  610  in accordance with cache management policy. The CCM  604  and the CFS  606  communicate requests, updates, responses, and errors with one another. 
     In the example of  FIG. 6 , the CFS  606  includes a requests queue  612  and an outage queue  614 . The requests provided to the CFS  606  by the NTS  602  or the CCM  604  are enqueued in the requests queue  612  for transmission to an application streaming server, such as a local application streaming proxy. 
     As used herein, a wireless network refers to any type of wireless network, including but not limited to a structured network or an ad hoc network. Data on a wireless network is often encrypted. However, data may also be sent in the clear, if desired. 
     As used herein, the term “embodiment” means an embodiment that serves to illustrate by way of example but not limitation. The techniques described in the preceding text and figures can be mixed and matched as circumstances demand to produce alternative embodiments.