Abstract:
Systems and methods for providing an automatic software upgrade over a satellite link. A server automatically downloads software updates over a satellite link to a client after such upgrades become available at the server. The download may be designated as mandatory or non-mandatory. Thus the download may be automatically performed or alternatively may prompt a user at the client to decide whether to accept the upgrade. The download eliminates the need for the client to be actively communicating with network infrastructure for the download to occur and enables the download to take place during low traffic time. Furthermore, the download requires little or no input from a user at the client.

Description:
RELATED APPLICATIONS 
     This application is a divisional of U.S. patent application Ser. No. 09/437,887, filed Nov. 9, 1999, now issued as U.S. Pat. No. 6,259,442, which is a continuation-in-part of U.S. patent application Ser. No. 09/106,937, filed Jun. 30, 1998, now issued as U.S. Pat. No. 6,023,268, which is a divisional of U.S. patent application Ser. No. 08/755,238, filed Nov. 22, 1996, now issued as U.S. Pat. No. 5,940,074, which is a continuation-in-part of U.S. patent application Ser. No. 08/660,088, filed Jun. 3, 1996, now issued as U.S. Pat. No. 6,034,689. This application is also related to U.S. patent application Ser. No. 08/656,924, filed Jun. 3, 1996, now issued as U.S. Pat. No. 5,918,013. The foregoing patents are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. The Field of the Invention 
     The present invention relates to systems and methods for providing an automatic software upgrade over a satellite link. More specifically, the present invention is directed to systems and methods for downloading the most recent version of a software application to a client with little or no input from a user at the client. 
     2. The Prior State of the Art 
     Computer software has proven to be a valuable tool for mankind. Software includes computer-executable instructions which, when executed, perform one or more predetermined functions. There are two major categories of software applications, system software and application software. System software includes the basic software needed to control a computer. Such system software may include, for example, an operating system and a database manager. Applications software uses services provided by the system software, and also provides its own methods to process data for a user. For example, applications software might perform word processing, spreadsheet calculation, flight simulation, or any other conceivable function or group of functions. 
     A problem encountered by computer users in general is that software applications tend to become outdated quickly. Accordingly, software suppliers periodically produce upgrades, which are often distributed in the same way that the original software was distributed, such as on magnetic or optical disks or other similar storage devices. However, the distribution of software upgrades on storage media such as these has disadvantages. For example, it is inconvenient and sometimes annoying for the user to have to repeatedly install software upgrades, which can be a time-consuming process. Further, a user may not be aware that an upgrade is available or necessary, or the user may forget to obtain or install the upgrade. The failure or delay in installing an upgrade can be detrimental since the upgrade may add valuable new features to the software or remedy a “bug” (i.e., error) in the software. Therefore, what is desired is a technique for allowing a software upgrade to be automatically provided over a network in a manner which requires little or no effort on the part of the user. 
     Another problem encountered by computer users is that sometimes software or data files becomes corrupted. A “corrupted” file is a file that has been changed presumably unintentionally by a failure in either hardware or software, causing the bits within the file to be altered so as to render the file unreadable as intended. Typically, the corrupted file can only be fixed by re-installing the software, or recovering the data from a backup. Re-installing the software can be time consumer and annoying to the user. Furthermore, recovering of data also conventionally requires extensive user interaction. Also, the user may not have the knowledge or capability to reinstall the software or recover the data. Therefore, what is also desired is a technique for fixing a corrupted file which requires little or no effort on the part of the user. 
     SUMMARY OF THE INVENTION 
     The present invention relates to upgrading software stored on a client, such as a computer or set-top box. In one implementation of the invention, a software upgrade is transmitted to the client via a satellite link. The software upgrade occurs automatically with little if any input required from a user. Thus, the upgrade is much more convenient to the user than the traditional methods of upgrading software using a magnetic or optical disk that contains the upgrade. Furthermore, since the upgrade is automatic, there is no risk that the upgrade will be forgone because the user has forgotten or is unaware of the upgrade. Thus, the user can easily and consistently have access to the most recent version of the software available. 
     As soon as one of the plurality of servers accesses a software upgrade corresponding to the software stored on the client, the server transmits the upgrade to the client over a satellite link. Since the download can occur via satellite transmission, the client need not be linked to or actively communicating over the network infrastructure for the download to occur. Thus, the server might download the upgrade during a low traffic time such as during the night. When the client next begins operation, the client already has the upgrade of the software without the user having done anything. 
     The present invention may be implemented in a networked computer system having servers connected to a network infrastructure. This network infrastructure may be a local-area network such as an Ethernet or Token ring, or may be a wide-area network such as the Internet. The software to be upgraded is located on a client also connected to the network infrastructure. 
     The client system may be, for example, a WebTV™ system which includes a television monitor on which to display information retrieved over the network infrastructure. In the case of the Internet, this information might include, for example, a Web page. The server that transmitted the upgrade software may be, for example, a WebTV™ server. In this case, the upgrade software may be an Internet browser. 
     Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims. These and other objects and features of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In order that the manner in which the above-recited and other advantages and objects of the invention are obtained, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which: 
     FIG. 1 illustrates several WebTV® client systems connected to a WebTV® server system; 
     FIG. 2 illustrates a WebTV® server system; 
     FIG. 3 illustrates a WebTV® client system; 
     FIG. 4 is a block diagram of an electronics unit of a WebTV® client system; 
     FIG. 5 illustrates the functional relationship between hardware and software in the client processing system of FIG. 1; 
     FIG. 6 is a flow diagram illustrating a reset routine for a WebTV® client system; 
     FIG. 7 is a flow diagram illustrating a normal start-up routine for initiating an upgrade of a WebTV® client system over the network; 
     FIG. 8 is a flow diagram illustrating a routine for initiating a download for the purpose of upgrading a WebTV® client system; 
     FIG. 9 is a flow diagram depicting a routine for transmitting software upgrades to clients via a satellite link; 
     FIG. 10 is a flow diagram illustrating a routine for initiating a download to correct an error; and 
     FIG. 11 is a flow diagram illustrating a routine for downloading to the WebTV® system from the network. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention relates to techniques for obtaining and maintaining operable and updated versions of software at a client connected to a network. In one embodiment, a satellite link in a network is used to download a new version, or an upgrade, of software stored at the computer or set-top box. 
     In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be evident, however, to one skilled in the art that the present invention may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to facilitate description. 
     Embodiments within the scope of the present invention include computer-readable media having computer-executable instructions or data structures stored thereon. Such computer-readable media can be any available media which can be accessed by a general purpose or special purpose computer such as a set-top box. By way of example, and not limitation, such computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired computer-executable instructions or data structures and which can be accessed by a general purpose or special purpose computer. 
     When information is transferred or provided over a network or another communications connection to a computer, the computer properly views the connection as a computer-readable medium. Thus, such a connection is also properly termed a computer-readable medium. Combinations of the above should also be included within the scope of computer-readable media. Computer-executable instructions comprise, for example, instructions and data which cause a general purpose computer, special purpose computer, or special purpose processing device such as a set-top box to perform a certain function or group of functions. 
     Although not required, the invention will be described in the general context of computer-executable instructions, such as program modules, being executed by computers or set-top boxes in network environments. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Computer-executable instructions, associated data structures, and program modules represent examples of the program code means for executing steps of the methods disclosed herein. 
     Those skilled in the art will appreciate that the invention may be practiced in network computing environments with many types of computer system configurations, including set-top boxes, personal computers, hand-held devices, multi-processor systems, microprocessor-based or programmable consumer electronics, network PCs, minicomputers, mainframe computers, and the like. The invention may also be practiced in distributed computing environments where tasks are performed by local and remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in both local and remote memory storage devices. 
     In one embodiment, the present invention is implemented in a set-top box that is connected to a television and to one or more servers over the Internet. The set-top box includes a processing system that executes browser software to enable a user to browse through World-Wide Web pages displayed on the television using a remote control device. As will be described below, the browser is upgraded or reconfigured by downloading to the set-top box replacement software or data transmitted from a server over the satellite network and then writing the replacement software or data into a programmable, non-volatile memory in the set-top box. 
     For example, the present invention may be included in a system known as WebTV®, which uses a standard television set as a display device for browsing the Web and which connects to a conventional network, such as the Internet, using standard telephone, ISDN, or similar communication lines. In accordance with the present invention, a user of a WebTV® client system can utilize WebTV® network services provided by one or more remote WebTV® servers. The WebTV® network services are used in conjunction with software running in a WebTV® client system to browse the Web, send electronic mail, and to make use of the Internet in various other ways. The WebTV® servers function as proxies by retrieving, from a remote server, Web pages or other data requested by a WebTV® client system and then transmitting the requested information to the WebTV® client system. Although the invention is described herein largely in the context of WebTV® components, the invention can be practiced with any other networks of components that are adapted to perform the functions disclosed herein. Thus, any reference to WebTV components, networks, services, etc. also apply to any other analogous components, networks, and services. 
     1. System Overview 
     FIG. 1 illustrates a configuration of a WebTV® network with which the invention can be practiced according to one embodiment. A number of WebTV® client systems  1  (hereinafter, “client 1”) are coupled to a modem pool  2  via direct-dial, bi-directional data connections  29 , which may be telephone lines (POTS, i.e., “plain old telephone service”), ISDN (Integrated Services Digital Network), T-1, or any other similar type of connection. The modem pool  2  is a conventional modem pool, such as those provided by Internet Service Providers (ISPs). The modem pool  2  is coupled typically through a router, such as that conventionally known in the art, to a number of remote servers  4  via a conventional network infrastructure  3 , such as the Internet (hereinafter, “the Internet 3”). 
     The WebTV® system also includes a WebTV® server system  5  (hereinafter, “the server 5”) which specifically supports the clients  1  by, for example, providing the WebTV® services to the clients  1 . Each of the clients  1  can communicate with the server  5  either directly or indirectly through the Internet  3  via the modem pool  2  using connections  29 . In addition, information may be downloaded from the server  5  to the client  1  using a conventional satellite link  29 ′. 
     A. Server System Architecture 
     The server  5  includes one or more computer systems generally having the architecture illustrated in FIG.  2 . It should be noted that the illustrated architecture is only exemplary; the server  5  is not constrained to the illustrated architecture. The illustrated architecture includes a central processing unit (CPU)  50 , read-only memory (ROM)  51 , random access memory (RAM)  52 , a mass storage device  53 , a modem  54 , a network interface card (NIC)  55 , a satellite transmitter  56 , and various other input/output (I/O) devices  57 . Mass storage device  53  includes a magnetic, optical, or other equivalent storage medium I/O devices  57  may include any or all of devices such as a display monitor, keyboard, cursor control device, etc. Modem  54  is used to communicate data to and from remote servers  4  via the Internet. The satellite transmitter  57  is used to transmit information to the client  1  over the satellite link  29 ′. 
     As noted above, the server  5  may actually comprise multiple physical and logical devices connected in a distributed architecture. Accordingly, NIC  55  is used to provide data communication with other devices that are part of the WebTV® services. Modem  54  may also be used to communicate with other devices that are part of the WebTV® services and which are not located in close geographic proximity to the illustrated device. 
     B. Client System Architecture 
     FIG. 3 illustrates a client  1  with which the invention can be practiced according to one embodiment. The client  1  includes an electronics unit  10  (hereinafter referred to as “the WebTV® box 10” or “the box 10”, an ordinary television monitor  12 , and a hand-held remote control  11 . In an alternative embodiment of the present invention, the box  10  is built into the television set  12  as an integral unit. The box  10  includes hardware and software for providing the user with a graphical user interface, by which the user can access the WebTV® network services, browse the Web, send e-mail, and otherwise access the Internet. 
     The client  1  uses the television set  12  as a display device and an audio output device. The box  10  is coupled to the television set  12  by a link  6 . The link  6  includes an audio channel for generating sound from the television&#39;s speaker and a video channel in the form of RF (radio frequency), S-video, composite video, or other format. The communication link  29  between the box  10  and the server  5  is either a telephone (POTS) connection  29   a , an ISDN connection  29   b , or any other type of terrestrial link. Connections  29   a  and  29   b  represent examples of two-way communications links. In addition, FIG. 3 illustrates a satellite link  29 ′, which is a one-way communication link to the client  1 . The box  10  receives AC (alternating current) power through an AC power line  7 . 
     Remote control  11  is operated by the user in order to control the client  1  to browse the Web, send e-mail, and perform other Internet-related functions. The box  10  receives commands from remote control  11  via an infrared (IR) communication link. In alternative embodiments, the link between the remote control  11  and the box  10  may be RF or any equivalent mode of transmission. 
     The box  10  includes application software which, when executed by a processor in the box  10 , provides the user with a graphical user interface by which the user can access the WebTV® network services and browse the Web. The application software is automatically executed upon application of power to the box  10 . 
     FIG. 4 shows the internal components of the box  10 . Operation of the client  1  is controlled by a CPU  21 , which is coupled to an Application-Specific Integrated Circuit (ASIC)  20 . The CPU  21  executes software designed to implement features of the present invention. ASIC  20  contains circuitry which is used to implement certain functions of the WebTV® system. ASIC  20  is coupled to an audio digital-to-analog converter  25  which provides audio output to television  12 . In addition, ASIC  20  is coupled to a video encoder  26  which provides video output to television set  12 . An IR interface  24  detects IR signals transmitted by remote control  11  and, in response, provides corresponding electrical signals to ASIC  20 . A standard telephone modem  27  and an ISDN modem  30  are coupled to ASIC  20  to provide connections  29   a  and  29   b,  respectively, to the modem pool  2  and to the server  5 . Note that, while the illustrated embodiment includes both a telephone modem  27  and an ISDN modem  30 , either one of these devices will suffice to practice the present invention. Further, in various other embodiments, the telephone modem  27  and the ISDN modem  30  each may be replaced by or supplemented with other communications devices, such as a cable television modem. In addition, in other embodiments, communication with the server  5  might be made via a token ring or Ethernet connection. Note that the box  10  also may include a cable television modem (not shown). A satellite receiver  33  is coupled to the ASIC  20  to receive data over the satellite link  29 ′. 
     Also coupled to ASIC  20  is mask Read-Only Memory (ROM)  22   a,  a flash memory  22   b,  and a Random Access Memory (RAM)  23 . Mask ROM  22   a  (which is so named because it is non-programmable) provides storage of certain program instructions and data, as will be described below. Flash memory  22   b  is a conventional flash memory device that can be written to (programmed) and erased electronically. Flash memory  22   b  provides storage of the browser software as well as data. In one embodiment, a mass storage device  28  is included in the box  10  and coupled to ASIC  20 . The mass storage device  28  may be used to input software or data to the client or to download software or data received over connection  29  or  29 ′. The mass storage device  28  includes any suitable medium for storing machine-executable instructions, such as magnetic disks, optical disks, and the like. 
     As mentioned above, the box  10  includes application software including a Web browser. Referring now to FIG. 5, the above-mentioned application software  31  operates in conjunction with operating system (OS) software  32 . The OS software  32  includes various device drivers and otherwise provides an interface between the application software  31  and the system hardware components  40  (i.e., the elements illustrated in FIG.  4 ). 
     In one embodiment, the application software  31  and the OS software  32  are stored in flash memory  22   b.  It will be recognized, however, that some or all of either the application software  31  or the OS software  32  or both can be stored in any other suitable storage medium, such as mask ROM  22   a  or mass storage device  28 , in various embodiments. 
     As mentioned above, steps according to the present invention are embodied in machine-executable instructions according to one embodiment. For example, in one embodiment, the present invention is carried out in the WebTV® box  10  by the CPU  21  executing sequences of instructions contained in mask ROM  22   a,  flash memory  22   a,  or RAM  23 , or a combination of these devices. More specifically, execution of the sequences of instructions causes the CPU  21  to perform the steps of the present invention. These steps will be described below. 
     Instructions for carrying out the present invention may be loaded into memory from a persistent store, such as mass storage device  28 , and/or from one or more other computer systems over a network, such as the server  5  or a remote server  4 . For example, such a server system may transmit a sequence of instructions to the client  1  in response to a message transmitted to the server system over the Internet  3  by the client  1 . As the client  1  receives the instructions via a network connection, such as modem  27 , modem  30 , or satellite receiver  33 , the client  1  stores the instructions in a memory. The client  1  may store the instructions for later execution or execute the instructions as they arrive over the network connection. 
     In some embodiments, the downloaded instructions may be directly supported by the CPU  21 . Consequently, execution of the instructions may be performed directly by the CPU  21 . In other embodiments, the instructions may not be directly executable by the CPU  21 . Under these circumstances, the instructions may be executed by causing the CPU  21  to execute an interpreter that interprets the instructions, or by causing the CPU  21  to execute instructions which convert the received instructions into instructions that can be directly executed by the CPU  21 . 
     Certain embodiments and aspects of the present invention may be carried out in the server  5 , instead of (or in addition to) being carried out in the client  1 . For example, the CPU  50  of the WebTV server  5  may execute instructions stored in memory to perform steps in accordance with the present invention. 
     In various embodiments, hardwired circuitry may be used in place of, or in combination with, software instructions to implement the present invention. Thus, the present invention is not limited to any specific combination of hardware circuitry and software, nor to any particular source for the instructions executed by a computer system. 
     2.Remote Download 
     As indicated above, the browser software can be upgraded, reconfigured, or restored downloading to the box replacement software or data transmitted from a server via the Internet, a direct phone connection, or via a satellite link  29 ′. FIGS. 6-11  illustrate various techniques of upgrading and restoring software at the client. 
     The programmable nature of flash memory  22   b  and its ability to retain programmed information in the absence of power are used to advantage in performing such an upgrade or reconfiguration. As will be explained in greater detail below, replacement software or data transmitted from the server  5  (or another server designated by the server  5 ) is automatically written into the flash memory  22   b  in the box  10 . In addition, the flash memory can be used to store various resources downloaded from the Web, such as Java applets (programs), so that such resources will be retained in the event of loss of power to the client  1 . Note that the present invention does not necessarily require use of a flash memory for these purposes; other forms of programmable non-volatile memory may be used, such as an electrically-erasable programmable ROM (EEPROM). 
     A download from the Internet  3  can be performed for purposes of upgrading the client  1  or reconfiguring the client  1  to correct an inconsistent state or corruption (e.g., an error in the program instructions or data). The client  1  determines whether a download from the network should take place each time the client  1  is reset. More specifically, a download will be performed if, upon reset, the client system  1  detects an error condition or, in the case of an upgrade, the client system  1  finds a download request in memory. If the satellite link  29 ′ is available, the server  5  might initiate a download to download browser software updates as they become available, without requiring a request from the client  1 . 
     FIG. 6 illustrates a method  600  performed by the client for restoring corrupted software according to a first embodiment of the invention. In this embodiment, the method may be embodied in a reset routine that is performed any time the client  1  is reset during operation or any time the box  10  is powered on. For example, the client system  1  may perform the method  600  of FIG. 6 by execution of start-up instructions stored in the mask ROM  22   a  (FIG.  4 ). 
     In step  601 , the validity of the stored program instructions (e.g., an Internet browser) is checked to ascertain whether a corrupted state exists in the computer instructions stored on the client  1  using a step of automatically checking. These computer instructions may be stored, for example, on the flash memory  22   b  of the client system  1 . This step of automatically checking may be performed by the client system  1  in response to software, hardware, or a combination of both. Any of a variety of routines may be used to check the validity of the stored instructions such as, for example, a conventional checksum technique. 
     If the contents are valid (yes in decision block  602 ), then the normal start routine is performed in step  603 . If the contents of flash memory  22   b  are corrupted (no in decision block  602 ), then an error download routine is performed (step  604 ). In the error download routine, some or all of the corrupt information in the flash memory  22   b  is replaced by correct information downloaded from the server  5 . The error download routine is described further below with respect to FIG.  9  and FIG.  10 . Thus, the WebTV® system allows errors in the programming or data to be detected and automatically corrected by performing the error download routine, without intervention by the user of the WebTV® client system  1 . 
     FIGS. 7 and 8 illustrate an optional extension of method  600  of FIG. 6, whereby a new version or upgrade of software is automatically made available to the client system. FIG. 7 depicts a routine  700  by which an upgrade of the Internet browser is initiated during a normal start-up (e.g., step  603  of FIG.  6 ). Initially, the client  1  automatically connects to the WebTV® server  5  (step  701 ). Generally, this connection is made via the modem pool  2  by executing a connection script. If an upgrade is determined to be available (yes in decision block  702 ), and the upgrade is designated as mandatory (yes in decision block  703 ), then the server  5  sends a command to the client  1  to cause a download request to be written into the flash memory  22   b  of the client  1  (step  704 ). The client  1  is then commanded by the WebTV® server  5  to reset (step  705 ). On the other hand, if an upgrade is determined to be available (yes in decision block  702 ), but the upgrade is not designated as mandatory (no in decision block  703 ), then the client  1  prompts the user to either accept or decline the upgrade (step  706 ). If the upgrade is accepted (yes in decision block  707 ), then the client  1  resets (step  705 ). If not (no in decision block  707 ), the routine ends. 
     FIG. 8 illustrates portions  800  of the normal start-up routine for initiating an upgrade. Initially, the client  1  determines whether a download request is present in flash memory  22   b  (decision block  801 ). If not (no in decision block  801 ), the browser program is started normally (step  808 ). If a download request is found in flash memory  22   b  (yes in decision block  801 ), then it is next determined whether a connection script is present in flash memory  22   b  (decision block  802 ). 
     As mentioned above, the connection script is executed to establish communication with the WebTV® server  5  or the modem pool  2 . Generally, a local connection script is stored in flash memory  22   b  to allow connection to the local modem pool  2 . A default connection script is stored in mask ROM  22   a,  which allows direct connection to the WebTV® server  5  using a toll-free (e.g., “1-800-”) telephone number. The default connection script is generally used only if a local connection script is not found in flash memory  22   b.    
     Referring still to FIG. 8, if the local connection script is found in flash memory  22   b  (Yes in decision block  802 ), then the client  1  uses that connection script to connect to the WebTV® server  5  via the local modem pool  2  (step  803 ). Assuming such connection is made, a determination is then made as to whether an IP (Internet Protocol) address, a port, and path information for the upgrade is stored in the flash memory  22   b  (decision block  804 ). The WebTV® server  5  may provide such information to the client  1  if the upgrade is to be downloaded from a server other than a default server, which may be the WebTV® server  5 . If such information has been provided, then the client  1  connects to the specified server (step  805 ), requests the specified file (step  806 ), and initiates downloading of the file (step  807 ). If an IP address, port, and path are not found in flash memory  22   b  (no in decision block  804 ), then the client  1  connects to the default server using a default IP address, port, and path stored in mask ROM  22   a  (step  810 ). A default upgrade file is then requested using this stored information (step  811 ). In step  811 , the client  1  also indicates to the default server which version of software it is currently running, so that the default server can determine the proper default file for that client system. Downloading of the default file is initiated in step  807  after the client  1  has requested a file. As mentioned above, downloading to the client  1  occurs via the Internet  3  via the modem pool  2 . Once downloaded, the information is automatically decompressed (if compression was applied) and written into flash memory  22   b  the client system  1 . 
     Hence, an optional upgrade is performed automatically without any input from the user of the client, other than the user&#39;s  answering a prompt on whether to accept the upgrade. A mandatory upgrade is performed without any input from the user and, in fact, can be performed without informing the user, if desired. 
     While FIG. 7 and 8 illustrate automatic upgrading of software as the client system initiates a user session, the invention also extends to methods of upgrading software via a satellite link. Such upgrading of software via a satellite link may be conducted dependently of any initiation of a user session and independently of any process for checking for corrupted software. Using a satellite link, upgrades of software may be initiated at any time that the server gains access to a new version of software. FIG. 9 illustrates a method  900  whereby software is upgraded via the satellite link. Specifically, whenever there is an upgrade of the browser software, the software is made available to server  5  (step  901 ). If, according to decision block  902 , client  1  is to receive the upgrade, the server  5  downloads the upgrade replacement program instructions to the client  1  (step  903 ). This is possible since the server  5  establishes the satellite link  29 ′without the two-way communication being established between server  5  and client  1 . Thus, the client  1  need not affirmatively do anything in order to receive the downloaded upgrade over the satellite link  29 ′ from the server  5 . 
     The upgrade can be downloaded to client  1  at a time that client  1  is not engaging in two-way communication with server  5 . In other words, the upgrade can be received via the satellite link at a time that client  1  has not logged on to server  5  and is otherwise not actively directing communication to the server. Moreover, the upgrade can be received at a time that client  1  is powered off. In this context, the term “powered off” refers to a state of the client wherein features other that ther ability ot receibe downloaded data from the statellite line are not enabled. For instance, in a powered off state, client  1  can receive downloaded software upgrades via that satellite, while being unable to browse the Internet or direct communication to server  5 . When client  1  receives a software upgrade in a powered off state, the upgrade is stored at the client so that it can potentially replace the software stored at the client when the client is powered on. 
     An upgrade received according to the method of FIG. 9 can optionally be designated as mandatory or not mandatory by, for example, server  5 . Designation of an upgrade as mandatory or not mandatory has been previously described in reference to FIG.  7 . In the context of the method of FIG. 9, which uses a satellite link to download upgrades, the upgrades are transmitted to client  1  regardless of their mandatory or non-mandatory status. Mandatory upgrades automatically replace the prior version of the software at the client. Non-mandatory upgrades, however, only replace the prior version of software after the user of client  1  has been prompted to accept the upgrade and after the user has responded by providing user input indicating acceptance of the upgrade. 
     As stated above, the methods of FIG.  7  and FIG. 8 are optionally performed when the validity of the stored program information is confirmed (yes in decision block  602  of FIG.  6 ). However, if the step of automatically checking ascertains the existence of a corrupted state in the stored program instructions (no in decision block  602  of FIG.  6 ), the client  1  automatically corrects the stored program instructions as is now described. 
     First, the client system  1  automatically connects to at least one of the remote servers  4  without the need for intervention from the user and, if desired, without informing the user of the connection. Thus, embodiments within the scope of the present invention include a means and step for automatically connecting the client system  1  to at least one of the server systems  4  or  5  that contains a replacement for the stored program instructions of the client system  1 . 
     There are a variety of ways for connecting a client system to a server system. If the location of the replacement program instructions is known, then a request can be automatically generated and transmitted over the Internet  3  to the appropriate server  4  or  5 . 
     Another example of a method of automatically connecting the client  1  to a server that contains the replacement is represented by method  1000  of FIG.  10 . Initially, the client  1  connects to the WebTV® server  5  directly using the default toll-free number stored in mask ROM  22   a  (step  1001 ). Once connected, the client system  1  obtains a local connection script from the server  5  (also step  1001 ). The client system  1  then disconnects from the server  5  (step  1002 ) and then reconnects to the server  5  via the local modem pool  2  using the local connection script (step  1003 ). The client  1  then further establishes a connection to the default server using the default IP address, port, and path stored in mask ROM  22   a  (step  1004 ). 
     After the client system  1  has connected to the appropriate server  4  or  5  that contains the replacement program instructions, the client  1  downloads the replacement program instructions from the server that contains the replacement. Accordingly embodiments within the scope of the present invention includes a means and step for automatically downloading the replacement from the server that contains the replacement. 
     FIG. 11 illustrates the downloading process  1100  in greater detail. To initiate downloading, the client system  1  transmits a request to the default server (step  1101 ). For example, the request may be for the replacement software from the default server using the default IP address, port, and path. The client  1  also indicates to the server which version of software it is currently running, so that the server can determine the proper default file for client  1 . 
     In one embodiment, the client system  1  requests the replacement program instructions by block number. In this case, the client system  1  receives certain block information (step  1102 ) from the default server that will transmit the data, including the size of the block to be downloaded, an identification of the next block to be downloaded, the address in flash memory  22   b  to which the current block is to be written, and a description of any data compression that is to be applied before transmission over the Internet  3 . The data is then transmitted over the Internet  3  to the client  1 . 
     The client system  1  then receives the data (step  1103 ) via the network connection  29  and loads the data into RAM  23 . The client system  1  decompresses the data (step  1104 ), assuming data compression was used. The client  1  writes the decompressed data into flash memory  22   b  (step  1105 ) using the address received in step  1102 . If there is another block to be downloaded according to the next block information (yes in decision block  1106 ), the routine  1100  repeats from step  1101 . Otherwise, the routine ends. 
     Thus, various methods according to the invention for upgrading or restoring software stored at the client have been disclosed. Corrupted or inoperable software can be restored automatically when a client is powered on by receiving replacement software from the server. Outdated software can be replaced at any time by receiving at the client a download of a software upgrade via a satellite link. The methods of restoring corrupted software and upgrading outdated software can be practiced in combination or separately as desired. 
     The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.