Abstract:
A system for describing computing environments as electronic documents, programs or other types of electronic representation or data. The environment description can be easily created, transferred and ultimately used to create the specified environment for use by an end user, or users, in many different applications. The invention provides abstraction software and a user interface to allow a human user to specify a definition for the computing environment. Desired components are selected and included in the environment definition. Default components can be provided to help a user design a viable environment. Hardware and software components can also be associated with constraints so that, for example, incompatible components such as software that can not run on different central processing units, under certain operating systems, etc., will not be selected. Abstraction software can also use parameters to associate additional qualities, restrictions or properties with components. Environment definitions can be stored and transferred in a manner compatible with typical electronic information. Copies of definitions can be made. Definitions can be viewed by application programs, browsers, etc. Definitions can be edited by users with similar types of software, or with other, dedicated software. Environment definitions can be installed onto hardware and software resources by installation software. Environments can be installed on specific components from which the environment was originally abstracted, or on other sufficiently similar components. Environments can be remotely manipulated and accessed from computers, terminals, web browsers, handheld devices, or other devices. Various services can be provided, or implemented, with the system of the present invention. Examples of services include allowing interactive selection and loading of environments, uploading previously saved environments for storage and future use, replicating environments and distributing the environments as for a corporate-wide deployment in several countries, etc.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS  
       [0001]    This application claims priority from U.S. Provisional Application Ser. No. 60/232,602, filed Sep. 14, 2000, entitled “A System for Handling Computing Environments as Documents or as Programs and a Set of Services Based on the System.” This application is also related to U.S. patent application Nos. Attorney docket No.  020706-000110  US and Attorney docket No. 020706-000120US, entitled “User Interface for Dynamic Computing Environments Using Allocable Resources” and “System for Configuration of Dynamic Computing Environment Using a Visual Interface,” filed Sep. 15, 2000. Both applications and their disclosures are incorporated herein by reference for all purposes. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    The present invention relates in general to digital processing, and in particular to a system allowing computing environments to be treated as electronic documents or as software programs and to a set of services based on the system.  
           [0003]    Although the software components of a computer—the operating system and the set of applications running on top of it—abstractly determine the notion of a “computing environment,” in today&#39;s practice this notion is closely tied to the underlying hardware as well. Thus, for instance, computer A is considered to be a Windows NT desktop, while computer B is considered to be a Linux server, and computer C a Windows  98  laptop. The bewildering variety of hardware devices reinforces this notion.  
           [0004]    Furthermore, the notion of a computing environment can be extended, without loss of generality, to a collection of systems connected by a network. Again, in today&#39;s practice, this extended notion carries with it a close association to the underlying hardware, in particular to the individual computer&#39;s hardware and the networking hardware used for connecting these computers. For instance, a user connecting a laptop computer to a local area network may need to be aware of the vendor and type of the network card used.  
           [0005]    This tight coupling between a computing environment and the underlying hardware, with the added complexity of a networked system, introduces a host of avoidable—yet presently insurmountable—issues to be dealt with by any user intending to buy, provide or use a computing environment.  
           [0006]    For instance, an organization may decide to locate a computer in a conference room shared by the marketing and the engineering departments of the organization. The marketing department uses the computer for slide shows and requires the environment of the computer to include Microsoft Windows NT operating system and PowerPoint software. The engineering department uses the computer for product demonstrations and requires the environment to include Linux operating system. With prior art, the computer can provide one environment or the other but cannot readily be changed from one environment to another. The users are usually interested in their specific environments, not their specific computers.  
           [0007]    As another example, a system administrator of an organization may be assigned to provide technical support for all computer users within the organization. If the system administrator needs to fix a problem in a user&#39;s computing environment, he/she needs to physically visit the user&#39;s location. Using prior art, there is no possible way for the administrator to transfer the user&#39;s environment to—or replicate the user&#39;s environment at—the administrator&#39;s location.  
           [0008]    Thus, it is desirable to provide a system that decouples computing environments from the hardware as much as possible. Such a system will permit computing environments to be handled as abstractions, which are—at least partially—agnostic about hardware. Services based on such a system will provide increased flexibility for users and reduced maintenance for administrators. Thus the systems and services will be advantageous over prior art in improving the cost-benefit ratio of computing environments.  
         SUMMARY OF THE INVENTION  
         [0009]    A system for describing computing environments as electronic documents, programs or other types of electronic representation or data. The environment description can be easily created, transferred and ultimately used to create the specified environment for use by an end user, or users, in many different applications.  
           [0010]    One feature of the invention provides abstraction software and a user interface to allow a human user to specify a definition for the computing environment. Desired components are selected and included in the environment definition. Default components can be provided to help a user design a viable environment. Hardware and software components can also be associated with constraints so that, for example, incompatible components such as software that can not run on different central processing units, under certain operating systems, etc., will not be selected. Abstraction software can also use parameters to associate additional qualities, restrictions or properties with components.  
           [0011]    Environment definitions can be stored and transferred in a manner compatible with typical electronic information. Copies of definitions can be made. Definitions can be viewed by application programs, browsers, etc. Definitions can be edited by users with similar types of software, or with other, dedicated software.  
           [0012]    Environment definitions can be installed onto hardware and software resources by installation software. Environments can be installed on specific components from which the environment was originally abstracted, or on other sufficiently similar components. Environments can be remotely manipulated and accessed from computers, terminals, web browsers, handheld devices, or other devices. Various services can be provided, or implemented, with the system of the present invention. Examples of services include allowing interactive selection and loading of environments, uploading previously saved environments for storage and future use, replicating environments and distributing the environments as for a corporate-wide deployment in several countries, etc.  
           [0013]    Other advantages of the invention are described, including business models such as where a service provider can ensure reliability by having backups of environments that can be easily recalled and reinstated; data center management is facilitated; remote access of environments is made more efficient; and other benefits are achieved.  
           [0014]    In one embodiment the invention provides a method for creating an electronic document description of a computing environment installed on computing hardware. The method includes identifying at least one software component of the computing environment; and automatically generating an electronic document containing an identification of each of the at least one software component, the electronic document comprising instructions for automatically reconstructing the computing environment on first computing hardware or on other computing hardware.  
           [0015]    In another embodiment the invention provides a method for installing a computing environment on target computing hardware based on an electronic document description of the computing environment. The method includes obtaining an electronic document that contains a description of a computing environment to be installed; reading the electronic document; identifying candidate computing hardware for installation of the computing environment; selecting target computing hardware from the candidate computing hardware for installation of the computing environment; and installing at least one software component on the target computing hardware in accordance with data contained in the electronic document. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]    [0016]FIG. 1 is a block diagram showing an example of a computing environment.  
         [0017]    [0017]FIGS. 2A and 2B illustrate a document abstracting the environment of FIG. 1.  
         [0018]    [0018]FIG. 3 is a block diagram of a system for abstracting an environment as a document or program according to the present invention.  
         [0019]    [0019]FIG. 4 is a flow chart showing a process for abstracting an environment as a document or program according to the present invention.  
         [0020]    [0020]FIG. 5 is a block diagram of a system for installing a computing environment at a remote location according to the present invention.  
         [0021]    [0021]FIG. 6 is a block diagram of another system for installing a computing environment at a remote location according to the present invention.  
         [0022]    [0022]FIG. 7 is a flow chart showing a process for installing an environment according to the present invention.  
         [0023]    [0023]FIG. 8 is a flow chart showing steps in a process for installing an environment with hardware constraints.  
         [0024]    [0024]FIG. 9 is a flow chart showing steps in a process for instantiating and installing an environment with parameters.  
         [0025]    [0025]FIG. 10 is a flow chart showing steps in a process for installing an environment that requires third-party software. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0026]    In the description herein, the term “computing environment” (or simply “environment”) includes an operating system and all the applications and documents installed on top of it, or a collection of networked computing environments.  
         [0027]    An example of a computing environment is shown in FIG. 1. A web-site system comprises  100  Apache Web servers  100 - 199  (each on a Windows NT server) connected to Internet  10  and also connected to two Oracle DB servers  11 ,  12  (each on a Solaris server). This system can be “rolled” into an environment consisting of the Windows NT servers, the Web servers (along with their configuration files), the document tree(s) for the web-site, the Solaris servers, the DB servers, and additional software used for connections, if any.  
         [0028]    The present invention provides a system and method for abstracting environments as documents or programs, as well as a system and method for installing environments abstracted as documents or programs on compatible hardware. The system of the present invention can be used to support a number of business models, as the following description will make clear.  
         [0029]    The terms “document” and “program” are used interchangeably herein. As will be evident from this disclosure, the present invention handles environments as documents in the sense that they can be stored, copied, edited, etc. But, as will also be evident from this disclosure, environment “documents” may be run or installed in the manner of programs.  
       ABSTRACTING ENVIRONMENTS AS DOCUMENTS OR PROGRAMS  
       [0030]    With the present invention a computing environment may be abstracted out as an electronic document or a computer program.  
         [0031]    For example, the environment shown in FIG. 1 may be abstracted in an electronic document shown in FIG. 2A. FIG. 2A shows an Apache/NT environment  200 - 299  corresponding to web servers  100 - 199  respectively, and an Oracle/Solaris environment  21 ,  22  corresponding to each Oracle DB server  11 ,  12 . The environment document also includes information regarding the network connections, such as the IP address of each web server, the IP address of each database server, and the IP addresses of the gateway. The collection of IP addresses forms a network with a common prefix (192.168.1). The gateway is not explicitly shown in FIG. 1 but is implicitly represented by the fact that the environment is connected to the Internet. A gateway typically is some hardware or a combination of some hardware and software that interconnects two networks and hence is identified by two network addresses (i.e., IP addresses). In this case, the gateway connects the networked environment in FIG. 1 with the Internet and has one IP address (192.168.1.254) that is part of the networked environment and another IP address that is on the Internet (64.94.248.12). According to the present invention, each web server is an environment by itself, and each database server is an environment by itself. Thus, FIG. 2A refers to these as Apache/NT environments and Oracle/Solaris environments respectively, and these environments in turn can be abstracted as documents. For instance, FIG. 2B shows a document abstracting an Oracle/Solaris environment. This document provides information needed to replicate the Oracle/Solaris environment present in, e.g., server  11 . Those skilled in the art will appreciate the details of such a description and will recognize that similar descriptions can be created for other web server environments or other computing environments.  
         [0032]    [0032]FIG. 3 shows a system suitable for abstracting environments. User computer  310  comprises user interface  311 , local storage  312 , and microprocessor  313 , all coupled to bus  315 . Microprocessor  313  runs abstracting software that creates and edits an environment document or environment program in response to commands received from user interface  311 . Preferably, network interface  314  is also present and coupled to bus  315 . Network interface  314  enables communication between user computer  310  and an environment present on other hardware  320 , and may also enable communication with a remote facility  330 , where environment documents may be stored or installed. Network communication may be via local area network, Internet, modem connection, or other network technologies known in the art.  
         [0033]    [0033]FIG. 4 shows an example of steps performed by abstracting software running in microprocessor  313 . In step  401 , the software identifies the user&#39;s desired components. In the simplest embodiment, the abstracting software enables the user to identify the desired components of the environment using a visual interface such as the visual interface described in co-pending U.S. patent app. No. 09/663,252 filed Sep. 15, 2000 entitled USER INTERFACE FOR DYNAMIC COMPUTING ENVIRONMENT USING ALLOCATEABLE RESOURCES (sic) which is hereby incorporated by reference as if set forth in full in this document. For instance, a user may identify an operating system and one or more applications to be run. An environment may also include associated data and/or documents to be used in conjunction with the applications. These components are also identified by the user during step  401 . In order to abstract an environment  320 , all the required components must be accessible to the system performing the abstraction, i.e., system  310 . For example, the environment could be present on user computer  310  itself or as a remote environment  320  that is accessible to user computer  310 .  
         [0034]    Alternatively, in step  401  a user may also specify an environment without having access to the components. In this situation, a number of environments must have already been abstracted from hardware and stored either on local storage  312  or at remote facility  330 . The user selects from these environments a number of components to be included in the user&#39;s environment; the user may also accept a default environment defined by a service provider and stored at remote facility  330 . As with the abstracting process, the user preferably uses a visual interface to select components.  
         [0035]    Once the user has identified the components, in step  402  the abstracting software builds an environment document or environment program incorporating these components. An environment document or environment program may be pure binary code; however, top-level structure may be represented in any language that enables hierarchical data representations. A preferred embodiment uses XML as a data representation language for the top-level structure.  
         [0036]    Although one purpose of abstracting computing environments as documents according to the present invention is to abstract away from specifics of the hardware, some abstracted computing environments may still have dependencies on the hardware. For example, in the environment shown in FIG. 1, the Oracle DB server may require at least 100 MB of RAM and at least 800 MB of disk space, and the Apache web server may require that the processors of the Windows NT servers belong to the Intel x86 family. To flexibly address such requirements, the present invention provides that an environment program may also include a set of constraints defining a hardware component of the environment. In a preferred embodiment, step  402  includes a step of generating hardware constraints and including them in the environment program. The constraint set is preferably generated from a simple language of relational expressions and logical operators over numeric and string literals; for example, a constraint set for the system of FIG. 1 with the requirements stated above may be given by the expression: 
         “Windows NT/Apache={Arch=x86} and Solaris/Oracle ={Memory&gt;=100and Disk&gt;=800}”. 
         [0037]    Those skilled in the art will appreciate that this technique can be used to include constraints regarding any aspect of the environment, not just hardware; for instance, some versions of software application programs can not run under certain operating systems, or with certain versions of operating systems. Thus, an operating system can have constraints of certain types and versions of application programs, and vice versa.  
         [0038]    In a preferred embodiment, the process of abstraction optionally may include abstracting a set of parameters from the environment. Parameters may include specifics of the operating system (genre, version etc.), specifics of the application software (kinds, versions etc.), or the footprints of the application software (installation directories, configuration files etc.).  
         [0039]    Parameters may also include sets of possible parameters i.e., types. In such cases, the environment document or environment program created in step  402  may act as a template for different possible environments. For example, in the environment of FIG. 1, the computing environment (C) may be abstracted over the version of the Windows NT systems since no version number was specified. Then the template environment is C(WinNT_version).  
       TRANSMISSION AND REPLICATION OF ENVIRONMENTS  
       [0040]    In step  404 , the environment program is stored. The program may be stored locally, for instance, in local storage  312  of FIG. 3, or transferred via a network to a remote facility  330  where environment documents or environment programs may also be stored. Storage or transfer may require a transformation of the document in step  403 , for instance by using a special representation to avoid corruption, by encrypting the document for secrecy, by archiving to preserve integrity, or by compressing the document for efficiency. Numerous algorithms for performing such transformations of electronic documents are well known in the art. For instance, the “zip” software tool may be used for archiving and compressing. Alternatively, the “tar” software tool may be used for archiving and the “gzip” software tool for compressing.  
         [0041]    The document or program may also be replicated to create multiple copies of the same environment. Procedures for replicating (copying) electronic documents are well known in the art.  
         [0042]    The document or program may also be edited to modify the environment. There are two different approaches to modifying environment documents. In a preferred embodiment, the user installs an environment on hardware, modifies one or more components of the environment (e.g., adding a new web server in FIG. 1, or adding a new software to an existing web server in FIG. 1), and abstracts a new document representing the modified environment. This process implicitly maintains the integrity of the document, i.e., if the modifications to the environment were successful, then the abstraction process is automatically successful.  
         [0043]    In an alternative embodiment, a user edit the document directly. For instance, in the document shown in FIG. 2A, one could add another web server by just replicating an existing Apache/NT environment from the same document. This embodiment may not guarantee the integrity of the modified document for all such changes. For instance, in the document shown in FIG. 2A, if a user modifies an existing document corresponding to an Oracle/Solaris environment by adding a new database, the integrity of the system may not be completely verified until the environment is active, i.e., the document or program is installed. When a user performs a direct edit, the integrity check or consistency check can be abstracted as a constraint or a parameter using the techniques described in the previous section.  
       INSTALLING ENVIRONMENTS  
       [0044]    In an embodiment of the present invention, an environment program may be installed either on the hardware from which the environment was abstracted or on other sufficiently similar hardware.  
         [0045]    [0045]FIG. 5 is a block diagram illustrating a preferred embodiment of a system for installing environments on a variety of hardware. At least one user terminal  510  communicates via Internet  520  with server  530 . Server  530  accesses storage  535  for environment programs received from user terminal  510 ; storage  535  may also store locally created environments. Server  530  also preferably accesses user database  532 , a database of available hardware  533 , and a database of supported software  534 . Server  530  is also in communication with hardware  540 , where user environments can be installed. Hardware  540  may include one or more computers having any type of architecture desired. Hardware  540  may also include networking equipment such as routers, switches, domain name servers, etc.  
         [0046]    A user uses a terminal  510  to communicate with server  530  in order to configure environments on hardware  540 . In a preferred embodiment, user communication with server  530  is via a secured socket layer (SSL) such as layer  521 . Hardware  540  may also have its own connection to Internet  520 , independent of server  530 , preferably via SSL  545 , to enable user communication with installed environments.  
         [0047]    [0047]FIG. 6 illustrates an embodiment of the system of FIG. 5 suitable for providing computing environments to a large number of remote users. User computers (not shown) communicate via Internet  602  with a service provider&#39;s system  600 . Application server farm  614  provides the functionality of server  530 . Server farm  614  includes a plurality of servers, each running Enterprise Java Beans (EJB), which are software components that enable various features of the system and services. For example, Storage Manager handles all activities related to storing and retrieving environments. Oracle DBMS software running on server farm  614  provides access to databases of user information, hardware information, and software information.  
         [0048]    Environment storage is provided by RAID arrays  624 ,  626 ,  632 , and  634 . RAID arrays  624  and  626  communicate with server farm  614  via storage host CPUs  622  to provide “clean configurations.” Clean configurations are environments supported by the service provider that can be provided by replication to different users. RAID arrays  632  and  634  communicate with server farm  614  via configuration host CPUs  630  to provide “dirty configurations.” Dirty configurations are environments specified by users by editing or modifying clean configurations. These environments are specific to users and may not be used by others. Separating clean from dirty configurations provides protection for user&#39;s privacy and a measure of security for the service provider.  
         [0049]    The hardware for installing environments includes a plurality of user Linux boxes  636  and a plurality of user Win boxes  638 . NIS/DNS server farm  640  and Ethernet switch  628  are provided to support networked environments, such as the environment of FIG. 1.  
         [0050]    User communications with server farm  614  are via SSL  610 , scalable web switch  616 , and web server farm  618 .  
         [0051]    In a preferred embodiment, users may also communicate with installed environments on Linux boxes  636  and/or Win boxes  638 . VNC viewers running on Linux boxes  636  and Win boxes  638  enable this communication. SSL  604  provides a secure channel.  
         [0052]    The selection and interconnection of these devices, along with other degrees of control of these devices, allows a user to set up many sizes and types of processing architectures and environments.  
         [0053]    It is possible to use widely-varying components, or resources, other than those shown in FIGS. 5 and 6. The specific hardware and interconnections of FIGS. 5 and 6 are but one example of an architecture for providing allocable resources to enable configurable computing environments. For instance, many aspects of the present invention can be applied to smaller systems such as a single personal computer. The single computer can be configured with many types of hardware and software and thus is a configurable system in itself.  
         [0054]    An example installation process using the embodiment of FIG. 5 is shown in FIG. 7. Although not required by the invention, the installation process preferably begins with user authentication in step  701 , wherein user database  532  is queried to confirm that the user is authorized, e.g., by requiring the user to provide a password.  
         [0055]    Next, in step  702 , an instruction to install an environment program is received at server  530 ; this step may involve a user sending an environment program for installation to the server via a network or instructing the installer to retrieve and install an environment program from local storage  535 . If the environment program was transformed for transfer and/or storage, the installation process performs a reversal of the transformation(s) in step  703 .  
         [0056]    The installation process then selects hardware on which to install the environment (step  704 ) and installs the specified applications and documents on that hardware (step  705 ). As noted above with respect to FIGS. 5 and 6, the invention can be applied to a system such as a single personal computer; in that case, the selected hardware would be the computer itself, which may be the same computer that runs the installation process.  
         [0057]    According to the present invention, it is guaranteed either that the environment can be recovered identically to the saved form or that the environment can be recovered in a form that is “behaviorally equivalent” to the saved form. The “behavioral equivalence” of two environments will be pre-defined for each operating system, for each application within an operating system, and inductively for each combination of applications within an operating system.  
         [0058]    For instance, consider Apache web server  1  and Apache web server  2  (out of the 100) in FIG. 1. If web server  1  is saved with its log files as environment document  201 , as shown in FIG. 2A, and web server  2  is saved without including its logs files as environment document  202 , then documents  201  and  202  are behaviorally equivalent because log files do not affect the functionality of a web server, and everything else about the environments is the same (i.e., Apache, NT etc.). Thus, a document representing the environment of FIG. 1 need not actually include 100 copies of a document corresponding to an Apache web server on a Windows NT computer if all 100 servers are identical. Instead, one such copy would be enough to enable full reconstruction of the environment of FIG. 1.  
         [0059]    In a preferred embodiment, an environment program may include hardware constraints as described above. In such a case, in step  704  the installation process selects “compatible hardware,” i.e., any hardware “box” that satisfies all of the constraints of the environment program. To determine whether a computing environment can be installed on a given hardware box, the installation process needs only to establish that the given hardware is compatible hardware for the computing environment. For instance, if an environment has a constraint set given by the expression: 
         “Windows NT/Apache ={Arch=x86} and Solaris/Oracle ={Memory&gt;=100and Disk&gt;=800}”, 
         [0060]    then hardware with 
         “Windows NT/Apache={Arch=586} and Solaris/Oracle={Memory=200and Disk=1000}” 
         [0061]    would be compatible hardware; of course, hardware with the exact amount of memory and disk space may be available and would also satisfy the constraints.  
         [0062]    A process for selecting compatible hardware in step  704  is shown in FIG. 8. In step  801 , constraints are read from the environment document. In step  802 , the system consults its database of available hardware to identify one or more hardware boxes with properties that satisfy the constraints. Step  803  determines whether compatible hardware is found. If compatible hardware is found, in step  804  the “best” compatible hardware is selected. If only one option for compatible hardware exists, that option is selected. If multiple options exist, an algorithm is used to select the “best” option according to criteria defined by the service provider. For instance, if the environment requires at least 100MB of memory and the available hardware includes box A with 200MB and box B with 500MB, the algorithm could require that the cheapest box (i.e., box A) be selected. If no compatible hardware is found, the installation fails and the user is so notified.  
         [0063]    In other words, to the installation process, symbolic constraint variables such as “Arch” or “Memory” are nothing but names. It is therefore possible to build up arbitrarily complicated sets of constraints without having to incorporate machine-specific checks in the installation process.  
         [0064]    Additionally, in a preferred embodiment the environment program may be a template for different possible environments, as described above. In this case, the installation process is preceded by an instantiation process, which specifies values for the parameters. An example instantiation process is shown in FIG. 9. The first steps are identical to steps  701 - 703  shown in FIG. 7. After any transformations are reversed in step  703 , the installation process determines in step  901  whether the environment program is a template. If not, the process proceeds to step  704  and the remaining steps.  
         [0065]    If the environment program is a template, the installer determines parameter values in step  902  and creates an instance of the program with the appropriate values in step  903 . For example, suppose that the template environment is C(WinNT_version). The process of instantiation will determine an available version of Windows NT (e.g., 4.0) by consulting a database of available software/OS and create an instance C_WinNT — 4.0. This instance is an environment program, since the only parameter has been defined. If there are multiple parameters, steps  902  and  903  are repeated until all parameters have been defined. The instantiated program is then used in the remaining installation steps, beginning with step  704 .  
       REMOTE MANIPULATION OF ENVIRONMENTS  
       [0066]    As described above with respect to FIG. 5, environments installed on hardware  540  may be accessed remotely from a user terminal  510 . Further, user terminal  510  may be connected to the Internet through a wired or a wireless connection.  
         [0067]    In a further embodiment, environments may be stored remotely and installed after transferring over the network into local hardware. The installation process can be initiated by either side—by push or by pull. For example, in the system of FIG. 5, an environment stored in storage  535  may be transferred over the Internet to a user terminal  510  for installation, either at the user&#39;s request or at the instigation of server  530 .  
         [0068]    Other embodiments include remote access to installed environments and remote installation of environments. In the embodiment of FIGS. 5 and 6, the hardware boxes on which the environment is installed is located on the same network as the server that runs the software for installing environments. But this is not a necessary condition; the server and the hardware boxes could be on different networks, as long as there is a connection (e.g., via the Internet) between the two networks  
       SERVICES  
       [0069]    The foregoing systems and methods for handling computing environments as documents make possible a set of “externalization” services whereby a user interacts with a service provider via a network to create, replicate, store, and install environments. For purposes of such services, a system like that shown in FIG. 5 is suitable, where server  530  and hardware  540  are owned by the service provider while each of user terminals  510  is owned by a user.  
         [0070]    Some services will be apparent to one skilled in the art based on the foregoing disclosure. For instance, one service enables a user to interactively select an environment to be downloaded to a local machine or local network. The user may then save the selected environment for future use or install it and use it. Another service enables a user to upload a previously saved environment onto compatible hardware provided by a service provider or to a storage area provided by the service provider. Still another service enables a user to replicate an environment and to install multiple copies of the environment.  
         [0071]    Additional services can be provided based on the systems and methods disclosed above. One skilled in the art will be able to see that these systems and methods can provide, among others, the following services:  
         [0072]    One service enables a user to edit an environment to add, remove, or replace application software supported and/or licensed by the service provider. The service provider handles the provisioning of licenses and usage rights associated with the application software.  
         [0073]    Another service enables a user to invoke application-deployment software provided by the service provider to add, remove, or replace application software not supported or licensed by the service provider, herein referred to as third-party software. This feature may be handled by the installer process described above with regard to FIG. 7. As shown in FIG. 10, the installation step  705  optionally provides a process for adding third party software to an environment while still guaranteeing all the properties of the invention. In step  1001 , an application to be installed is identified from the environment document. In step  1002 , it is determined whether the service provider supports that application. If so, in step  1003 , the application is installed. If not, in step  1004 , application deployment software is invoked. This software verifies the user&#39;s license for the application, gets the application code (which may be in the environment document) and installs the application. In step  1005 , if more applications remain to be installed, control returns to step  1001 . If not, the installation software proceeds with the final steps of identifying (step  1006 ) and installing (step  1007 ) documents and/or data required by the environment.  
         [0074]    Another service enables a user to edit a program to add, remove, or replace data associated with the applications that are components of an environment.  
       BUSINESS MODELS  
       [0075]    Using the system and method of the present invention enables a number of business models.  
         [0076]    For example, a service provider can provide reliable, fault-tolerant computing environments. In this model, the service provider automatically makes a copy of the user&#39;s computing environment. If the user&#39;s environment is destroyed, the user is able to retrieve it from the service provider. Conversely, at regular intervals, the user may back up the environment with the service provider. If the user&#39;s hardware becomes damaged in some way, the service provider can quickly provide the user&#39;s environment to replacement hardware.  
         [0077]    As a second example, a service provider can provide high-capacity, scalable computing environments referred to as “data centers” or “network operation centers” (NOCs). These centers are large centralized locations that provide computing infrastructure (hardware, software and networking) to organizations. One embodiment of the present invention enables NOCs to easily accommodate dynamically changing needs of organizations. For instance, an organization may use a first network for its e-commerce operations, a second network for its internal operations, and a third network for its information web site. The e-commerce operation may need more resources during the Christmas shopping season, while the information web site may be doing webcasts of football games, leading to a need for extra resources on game days. So the resource requirements grow and shrink dynamically; for instance, the information web site may need 100 web servers on a “normal” day but 300 on game days. In an NOC using prior art systems, installing a new environment (e.g., converting a hardware box from the information web site configuration to the e-commerce configuration) typically takes days since installation is done manually, and frequent (e.g., every other day) repetition of an installation is not feasible. Using the present invention, a NOC provider may enable users to change environments installed on machines at the touch of a button. Thus the present invention makes environments scalable both in space and time (more machines in less time).  
         [0078]    As a further example, a service provider may also provide mobile environments. The service provider provides a collection of hardware that the user can access remotely, for instance through the World Wide Web or via a cell phone or personal digital assistant (PDA). This allows the user to access the environment virtually anywhere. Conversely, the environment may be copied to the user&#39;s system (e.g., local desktop, laptop, or PDA and occasionally backed up to the service provider&#39;s databases. This provides the user the same benefits as a remote environment without the costs of accessing the environment remotely. Moreover, mobile-environment users who want to use different environments at different times need not “carry” all the environments around; they can simply swap environments in and out on the same hardware (local or remote). For example, a software engineer may develop products using Linux, Java, Apache and emacs, and draft documents using Windows and Microsoft Word. Using the mobile environment service, this engineer can “carry” either one of the environments on his laptop and quickly swap environments on the same laptop by accessing the service provider.  
         [0079]    As a further example, a service provider may also provide tailored environments, also called Application Specific Environments (ASE). The service provider provides complete environments for particular problem-domains, such as an application-server environment, an inventory-management environment, and so on. Environments may also be created to cater to certain categories of users, for example, executives, accountants, designers and engineers For example, a standard Software Engineer&#39;s environment may include Linux OS; compilers for Java, C, and Perl (or other languages); editors; testing tools; and performance tools. A standard furniture designer&#39;s environment may include Windows OS, Microsoft Office (for documentation, project scheduling, etc.), 3-D visualization software for designs, and high-quality printing software. The service provider, instead of the user, handles installation and licensing issues for setting up these environments.  
         [0080]    As a further example, a service provider may also provide low maintenance environments, also called outsourced computing. In this model, the service provider owns the hardware and provides remote access to users. This offers users a number of advantages. For example, the service provides easy software installation services and update/patch services on a large scale (by replication). In addition, troubleshooting errors becomes simpler because of the ability to replicate an environment. For instance, intrusive/destructive testing can be performed on a replication of the troubled system while the system itself remains in use, without affecting the functionality or performance of the system. Replication also allows multiple tests to be performed in parallel on different copies of the system, thereby speeding up troubleshooting.  
         [0081]    Further, users can compare and evaluate different environments without large overhead costs in procuring, installing and maintaining the hardware and software over short periods of time. Still further, the service provider can provide versioning services for an environment—automatic check—pointing and saving at different states along with roll back.  
         [0082]    With the novel systems and methods provided by the present invention, a machine no longer needs to run a particular computing environment, nor does a particular computing environment need to run on a particular machine. A user chooses which computing environment to run. When the user&#39;s needs change, the computing environment is easily swappable for another one. Similarly, the user is not limited to running a particular computing environment on a particular machine as computing environments can be readily transferred from one machine to another. For example, a user can move an environment from a PC at home to a laptop, or place the environment in a centralized server that can be accessed from anywhere on the Internet.  
         [0083]    These features are brought about by providing an electronic document description of the environment and having a configuration system capable of automatically configuring resources in accordance with the environment&#39;s document description. Multiple copies of environments can be made and provided to others. Application vendors can provide entire computing environments to their customers, greatly easing installation issues. Additionally, environments can be modified. One can easily customize an environment for one&#39;s own purpose.  
         [0084]    Although the present invention has been discussed with respect to specific embodiments, these embodiments are merely illustrative, and not restrictive, of the invention. For example, as used herein, the term “electronic document” should be construed to include information that can be displayed to a human user as well as information that can be read or processed by hardware or software. A “software program” includes instructions or symbols that can be read or interpreted to direct functional actions in software or hardware. The terms “electronic document,” “document,” “software program” and “program” are each intended to broadly refer to any form of information, including physical and electronic representations.  
         [0085]    Thus, the scope of the invention is to be determined solely by the appended claims.