Patent Publication Number: US-7584470-B2

Title: Method and system for peer-to-peer software distribution with a package builder

Description:
FIELD OF THE INVENTION 
     This invention relates to the field of distribution of software or data. In particular, the invention relates to peer-to-peer software distribution. 
     BACKGROUND OF THE INVENTION 
     Software or data may be distributed from a server to a variety of client processor-based systems. Typically, software packages may be periodically sent to a large number of processor-based systems within a network. Examples of software and data which may be distributed are system software, updates to system software, applications, updates to applications, and other forms of data packages. Such software or data may be distributed from a central server to a large number of clients. Distributing software or data from a server to a large number of clients, particularly as required when a software update is released, involves a large amount of time and resources which increases the cost of such a software update. Devices which require software installation may be in the form of computers, mobile telephones, Personal Digital Assistants (hereinafter referred to as “PDAs”), devices with embedded software, etc. 
     As the use of mobile devices becomes more widespread through the use of wireless communication, the practicalities of providing updates to software or new software for the mobile devices is increasingly problematic and costly. 
     Distribution of software typically involves packaging a number of files into one or more containing files on a central server or distribution media. These file(s) are then sent over a network or communications medium, or directly to a target device where the file(s) are opened and installed. 
     By way of example, the following scenario is presented. 
     A first device, device A, downloads a software distribution kit from a server. This kit is an executable and, when run, extracts and installs the contained software, carrying out a configuration as necessary. 
     A second device, device B, requires the same software as device A, and two choices are available: 
     1) Download the software from the same server at which device A obtained the software. 
     2) Obtain the software from device A directly, provided device A is within communication range of device B. 
     It is assumed in this scenario that there are only two devices for simplicity. In reality, there may be an entire range of devices from which to select. 
     The first choice may be problematic for a number of reasons. The software may be large in size and may therefore take a long time to download due to bandwidth restrictions. This could mean significant expense in terms of download time due to the type of wide area network (WAN) in use. It could be problematic due to intermittent network access; this is particularly evident when the target server is some distance away in network terms, and a wireless network is involved. 
     Similarly, the server that holds the software repository could become unavailable preventing device B from downloading the software until the server is available again. This is particularly unacceptable in a business environment. 
     The second choice has a number of advantages that overcome deficiencies of the first choice. The software has already been downloaded by device A, shielding device B from any problems with the server. Download becomes less problematic or costly due to direct connection (peer-to-peer networking) with device A, which should be closer to device B and should involve a lower cost. 
     However, the problem with the second choice is that the software that device A downloaded has been un-packed and installed on that device. This is likely to mean that the method of installing the software on the device has been lost. For example, a template or base configuration file may have been configured to that particular device&#39;s specification upon installation. 
     This could be overcome by retaining the original software distribution kit; however, this is not guaranteed to exist. The packaged form may have been deleted for the following reasons:
         it was automatically cleaned up after the contents were extracted;   outside intervention deleted the file (i.e. user); or   the user deleted the installation file as there was not enough space on the device at the time to hold both the packaged and unpackaged forms of the software on the device. This last point is particularly relevant to mobile, pervasive, or embedded devices.       

     Some method for re-generating the packaged software distribution kit in its original form is required to enable re-distribution to other devices in a peer-to-peer networking environment. The solution is to enable a device to re-create the software distribution kit such that software can be redistributed to other devices for installation. This re-creation may be on the fly, as opposed to storing it locally hence consuming more resources. 
     Reverse-engineering of an installed software image to create the original, distributable kit allows devices themselves to act as peer-to-peer software distribution servers. This is particularly advantageous in the mobile world where many devices require the same software and currently have to go to some sort of centralized server to retrieve it. Each device becomes capable of acting as a software distribution server in order to propagate software to its neighbors. 
     A device may propagate the software to its neighbors in many different environments depending on the nature of the device. For example, if the device is a mobile telephone, it may distribute software updates to other mobile telephones which are within range in an office environment. Similarly, if the device is an onboard car computer, it may distribute software to other onboard car computers in a parking lot. 
     SUMMARY OF THE INVENTION 
     In accordance with one embodiment of the invention, there is provided a method for software and data distribution, comprising providing an original software package to a first device, installing the original software package and a package builder kit on the first device, wherein the package builder kit is adapted to build a software distribution kit, and transmitting the software distribution kit to a second device. 
     In accordance with another embodiment of the invention, there is provided a system for software and data distribution, comprising a first device comprising a processor and storage, and an original software package adapted for installation on the first device, wherein the original software package comprises an installation program adapted to install the original software package on the first device, and a package builder kit adapted to build a software distribution kit for transmission to a second device. 
     In accordance with yet another embodiment of the invention, there is provided a program product stored on a computer readable medium, comprising program code for performing the steps of receiving an original software package at a first device, installing the original software package and a package builder kit on the first device, wherein the package builder kit is adapted to build a software distribution kit, and transmitting the software distribution kit to a second device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the present invention will now be described, by way of examples only, with reference to the accompanying drawings in which: 
         FIG. 1  is a schematic diagram of a software distribution system in accordance with the prior art. 
         FIGS. 2A and 2B  are schematic diagrams of a software distribution system in accordance with one embodiment of the present invention. 
         FIGS. 3A and 3B  are block diagrams of a software distribution system, during and after re-distribution of software from a first device to a second device, in accordance with one embodiment of the present invention. 
         FIGS. 4A and 4B  are flow diagrams of a software package installation and a software package building process in accordance with one embodiment of the present invention. 
     
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION 
     A method and system for software and data distribution is described. Software is a computer program that makes computer hardware work. Software includes system software for an operating system which controls the workings of a computer hardware device and application software which perform tasks using a computer hardware device. 
     A computer hardware device which runs software may be any form of a wide range of devices with a processing capability including, as examples, computers, mobile telephones, PDAs, devices with embedded software, etc. Devices with the capability to run a computer software program may be provided to the consumer with pre-loaded software; however, the software may require updating in which case software updates must be distributed to the individual devices already in use. In addition, users may wish to install new software on devices. Data for use by a software program may also require distribution or updating. 
     Distribution of software in the form of system software, updates to system software, applications and updates to applications is generally carried out in two ways. Firstly, the software is distributed on portable storage media, such as CD-ROMs, floppy disks, etc. Secondly, software is downloaded from a computer server via a network. For example, with wireless technology, a mobile telephone software update can be downloaded from a server via wireless telecommunications. 
       FIG. 1  illustrates a system for software distribution as known in the prior art in which software is installed from software distribution kit  100  as provided on a portable storage medium, for example, a CD-ROM. Software distribution kit  100  may also be downloaded as a package from a server via a network communication. When software distribution kit  100  is downloaded, it may be stored on a receiving device as it is downloaded and then installed after it has been received, or it may be installed as it is downloaded. 
     The left side of  FIG. 1  shows components of software distribution kit  100  before installation. Software distribution kit  100  contains a plurality of files  101 ,  102 ,  103  comprising the software and a base configuration file or files  104 . 
     The right side of  FIG. 1  shows the software as installed on a device. Files  101 ,  102 ,  103  are typically installed to different directories on the device. As depicted in  FIG. 1 , File  1   101  and File  3   103  are installed in first directory  105  and File  2   102  is installed in second directory  106 . Base configuration file  104  is tailored to a device-specific configuration and installed in third directory  107  as customized configuration file  108 . 
     In any event, it should be noted that to provide for reverse-engineering of the installed software, sufficient information contained in software distribution kit  100  must be preserved. 
     Referring now to  FIG. 2A , a system of software distribution using software distribution kit  200  is shown. Software distribution kit  200  contains a plurality of files  201 ,  202 ,  203  comprising software, and base configuration file or files  204 . 
     The right side of  FIG. 2A  shows the software as installed on a device. Files  201 ,  202 ,  203  are typically installed to different directories on the device. As depicted in  FIG. 2A , File  1   201  and File  3   203  are installed in first directory  205  and File  2   202  is installed in second directory  206 . Base configuration file  204  is tailored to a device-specific configuration and installed as customized configuration file  208  in any suitable location, and is shown in  FIG. 2A  as located in third directory  207 . 
       FIG. 2A  depicts additional package builder kit  209 , which is extracted to a device&#39;s file system, in one example third directory  207 , and remains there for the lifetime of the software. Package builder kit  209  contains the following information:
         Original base configuration file(s)  204     Some form of descriptor file outlining what files were installed, and to which directories on the device (This provides for the files to be retrieved and put into a rebuild package.)   Associated checksums to confirm that the software package has been received correctly   A descriptor file describing the internal structure of the original software distribution kit package (This includes organization of files into directory structures, compression enabled, and checksums to ensure that the files are in place and valid.)   An executable program to build the distribution kit package using the above information and the actual code (i.e. files)       
     Referring now to  FIG. 2B , once software distribution kit  200  has been installed on a device, package builder kit  209  can be used to create new software distribution kit  210  to install the software from the device to a second device using direct, peer-to-peer distribution without being required to refer back to the original copy of software distribution kit  200 . New software distribution kit  210  is either substantially identical to the original copy of software distribution kit  200 , or a subset of kit  200  with restricted capabilities. For example, new software distribution kit  210  may be restricted to only re-distribute a software package to a particular brand of device, or a particular operating system. The second device must have an installer capability provided either as part of the base build package of the second device or by another mechanism in order to allow the second device to receive software distribution kit  210  from the first device. 
     In one embodiment, package builder kit  209  is constructed as part of an installation program of software distribution kit  200 . When the installation program of software distribution kit  200  is run on a device, the components of package builder kit  209  are installed on the device. When package builder kit  209  is invoked on the device, package builder kit  209  recreates distribution kit  210 . Software distribution kit  210  can be recreated either as a complete package stored to disk on the device, or alternatively, software distribution kit  210  can be recreated on-the-fly as it is used to distribute software to a second device so as to save disk space on the first device. Files may be overwritten during this process, if required. 
     In another embodiment, package builder kit  209  is provided as a unit in software distribution kit  200  including base configuration file  204 , plus any other information required to rebuild software distribution kit  210 . The described system allows any device that obtained and installed a software program from software distribution kit  200  to act as a re-distributor of that software program. 
     In yet another embodiment, a software agent is provided that handles installation requests. This agent delivers installed files as a series of components, in effect delivering a software distribution kit by building and sending data on-the-fly without initially creating a full software distribution kit. In other words, the agent would be responsible for creating a software distribution kit which contains only the components necessary for a particular device (i.e. the bare minimum components for that device). 
     The agent further provides a level of control over a software re-distribution process by controlling which specific sub-components of software distribution kit  200  are actually re-distributed to a second device. For example, files may be excluded which already exist on the second device, or are not required due to a differing operating system or hardware configuration. Alternatively, additional files could also be distributed to satisfy dependencies of the second device. 
     An example of one embodiment of the present invention is now described with reference to  FIGS. 3A and 3B . A software distribution kit is provided on storage medium  301  on which components of software are provided. The components include software files A, B, C  302 , a further file D  303  which is a configuration file (for example, an initialization file, e.g. file.ini), and an installation program  304 . 
     First device  310  is shown, on which software is to be installed using the software distribution kit provided on storage medium  301 . The software may be installed on first device  310  by any appropriate method, including downloading from another device. First device  310  has an installation capability in the form of installation system  314  which may be part of a base build package of first device  310  or may have been provided by another mechanism. 
     Installation program  304 , sometimes referred to as a set-up program, does most of the work of preparing a software program to work with a device on which it is to be installed by accommodating the specific system configuration of the device. Installation program  304  checks for other peripheral devices attached to device  310  and may request a user to choose from options, creates a storage location for software components, for example on a hard drive of the device, and modifies start up files of the device, as necessary. 
     As depicted in  FIG. 3A , first device  310  loads software from storage medium  301 . A copy of installation program  318  is loaded onto first device  310 . Installation program  318  runs copy program  319  to copy software files A, B, C  302  and to store copies  312  of software files A, B, C  302  in directories in a storage memory of first device  310 . Configuration file D  303  is also copied from storage device  301  and is customized for the configuration of first device  310 . Customized configuration file D′  315  is stored in a directory in a storage memory of first device  310 . 
     A package builder kit is provided as part of installation program  304  of the software distribution kit. When installation program  318  is run on first device  310 , the components of the package builder kit are installed on first device  310 . The components of the package builder kit include, copy  313  of original configuration file D  303 , a first descriptor file in the form of log  316 , a second descriptor file in the form of manifest  317 , and builder/validation program  309 . Copy  313  of original configuration file D  303  is stored in a directory of a storage memory of first device  310 . Log  316  keeps track of which files  302 ,  303  have been installed, and where these files are installed in directories of first device  310 . Log  316  also includes checksums. Manifest  317  provides details of the internal structure of the original software distribution package to enable placement and extraction. The details include the organization of files into directory structures, compression or encryption enabled, and associated checksums. An extraction process goes through all the files and a validation system looks at the extraction of the files to verify validity. 
     Builder program  309  is provided to build the recreation of the software distribution kit using the components of the package builder kit in the form of copy  313  of configuration file D  303 , log  316 , manifest  317  and copies  312  of files A, B, C  302  stored on first device  310 . When builder program  309  of the package builder kit is invoked on first device  310 , builder program  309  recreates the software distribution kit enabling software to be installed from first device  310  onto second device  320 . Builder program  309  may recreate the software distribution kit in its entirety before commencing installation on second device  320 , or alternatively, builder program  309  may recreate the software distribution kit on-the-fly as installation on second device  320  is taking place. 
     First device  310  has communication system  331  for communicating with communication system  332  of second device  320 . The communication can be via any suitable communication channel including wireless communication. Second device  320  has an installation capability in the form of installation system  324  which may be part of the base build package of second device  320  or may have been provided by another mechanism. Second device  320  may request the installation of the software from first device  310 . 
     Copy  324  of installation file  314  is first installed in second device  320  as shown in  FIG. 3A  including copy program  329 , builder program  339  including the validation system, the manifest, and log files  326 ,  327 . Referring now to  FIG. 3B , installation file  324  on second device  320  pulls down manifest file  317  and gets and copies (using copy program  329 ) software files A, B, C  322  from copies  312  on first device  310  together with copy  323  of the original form of configuration file D  313 . Manifest file  327  and log file  326  on second device  320  are filled as the installation process takes place. As installation file  324  installs the software files, configuration file D  313  is customized and stored as D″  325  for the configuration of second device  320 . Installation file  324  includes restart log  321 , which keeps track of the files as they are installed, and if an installation is interrupted, the installation can be re-started from the place at which it failed. 
     The inclusion of a package builder kit in software installed on second device  320  may be optional. A builder kit may be provided so that second device  320  can in turn recreate a software distribution kit for installation on a third device. In this case, components of a package builder kit are provided as part of installation program  324  installed on second device  320  including builder program  339 . When installation program  324  is run on second device  320 , components of a package builder kit are installed on second device  320 . Alternatively, as an optional measure of control of distribution, a package builder kit may not be provided to second device  320  in which case second device  320  cannot, in turn, pass the software onto a third device. 
     First device  310  may include advertiser file  333  which advertises to other devices any software distribution kits that device  310  has installed. Second device  320  communicating with first device  310  as consumer  334  may have shopping list  335  of software that device  320  would like to install. If device  320  locates a desired software distribution kit on first device  310 , an installation may take place automatically during a communication between devices  310  and  320 . When a request for software is received at first device  310  from second device  320 , builder program  309  is invoked through communication system  331 . 
     Builder program  309  includes a validation system which carries out a validity check of a software distribution package through manifest file  317  and log file  316 . The validity check ascertains if all files of a given software distribution package are valid, in that the files are all recorded to directories that exist, and that any extraction systems are present, etc. If a software distribution package is valid, the transfer request proceeds. If not, and files are missing or invalid, the transfer request is denied. Builder program  309  communicates with installation system  324  on second device  320  and hands across files that comprise a software package by reference to manifest  317  and log  316 . In addition, manifest file  317  on first device  310  may be updated to indicate if a given software distribution package is valid or invalid. If a package is invalid, advertiser  333  can stop advertising it as available, or can indicate that the version is invalid. A system manager may be provided on a device to check periodically if software distribution packages are valid and correctly shown in advertiser  333 . The system manager interrogates its software distribution kits and records the results accordingly. Further, an external service may manage a plurality of client devices. The external service can inform any one or more of the client devices that it wishes the device to obtain one or more particular software package(s). The client devices can then obtain the software during communication with other devices. 
     Referring now to  FIGS. 4A and 4B , flow diagrams show an exemplary installation of a software package on a first device, and the distribution of a software package already installed on a first device to a second device. 
       FIG. 4A  shows a flow diagram  400  describing the steps involved in installing a software package on a first device. The installation starts in step  401  and the contents of a software kit are extracted in step  402  to a temporary location. It is determined if there are files to process in step  403  and, if so, a file is copied in step  404  to a location on the device. In step  405 , the deployed location of the file is recorded in log  406 . Steps  404  and  405  are repeated for each file to be processed. If it is determined at step  403  that there are no more files to process, the method proceeds to the next step  407 . Copies of the original configuration and manifest files are stored in step  407 , and the package builder kit is copied to a location for preservation in step  408 . The configuration file(s) for this installation are configured in step  409  and the installation is finished at step  410 . 
       FIG. 4B  shows a flow diagram  420  describing the steps involved in distributing a software package already installed on a first device to a second device when invoking a package builder kit. The method starts at step  421  and determines if all the necessary file information is present in step  422 . If all the file information is not present, an error is reported in step  423  and the method finishes at step  432 , as it is not possible to recreate the software package. If it is determined in step  422  that all the file information is present, a list of the installed file locations is obtained in step  424  from log  406  created during the installation described in flow diagram  400 . 
     It is determined if there are files to process in step  425  and, if so, the position of the file in the original software package is obtained in step  426  from the manifest file. A copy of the file is made in step  427  from the file location and sent to the second device, such that the original software package structure is mimicked. Steps  426  and  427  are repeated for each file to be processed. If it is determined at step  425  that there are no more files to process, the method proceeds to the next step  428 . The original preserved configuration files are copied in step  428  to the second device. The software package is sent to the second device in step  429 . Optionally in step  430 , it is determined if compression is to be performed in step  431  on the software package. The method of distributing a software package as described in flow diagram  420  is then finished at step  432 . 
     The described method and system enable a device to act as a virtual software distribution storage medium. 
     The present invention is typically implemented as a computer program product, comprising a set of program instructions for controlling a computer or similar device. These instructions can be recorded on a computer readable storage medium such as a CD-ROM, or made available for downloading over a network such as the Internet or a mobile telephone network. 
     Improvements and modifications can be made to the foregoing without departing from the scope of the present invention.