Abstract:
A vehicle entertainment system includes seat controller cards (SCCs), each being programmed with a browser and operating as a microserver for managing Hyper-Text Transfer Protocol (HTTP) document requests issued by the browser. When the browser requests HTTP documents that are stored in a local memory of the SCC, the microserver retrieves the HTTP document from the local memory and provides it to the browser without accessing a system file server for the vehicle entertainment system. As a result, the processing load of the system file server is decreased and the response rate to a HTTP document request is increased.

Description:
REFERENCE TO RELATED APPLICATION 
     This application is related to, and being filed concurrently with, an application by Douglas Infiesto, entitled “Vehicle Entertainment System Having Built-In Test Environment Server,” Ser. No. 09/336,638 the contents of which are incorporated herein. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a vehicle entertainment system, and more particularly, to a vehicle entertainment system in which each passenger seat is provided with a seat controller card that is programmed as a server to manage hypertext document requests locally, without accessing a server for the vehicle entertainment system. 
     2. Description of the Related Art 
     Hypertext documents are computer files containing text and images with links, more commonly referred to as hyperlinks, to other hypertext documents. The coding language that is used to create hypertext documents is known as HyperText Markup Language (HTML). The protocol for moving hypertext documents across an interconnected network of computers, e.g., across the Internet or an intranet, is known as HyperText Transport Protocol (HTTP). This protocol requires an HTTP client program on one end and an HTTP server program on the other end. The HTTP client program is known as a browser. It is the software that displays hypertext documents and manages inputs thereto. The two most popular types of browsers are Netscape Navigators and Internet Explorers. The communications protocol that is used in the interconnected network of computers, e.g., the Internet or intranet, is Transmission Control Protocol/Internet Protocol (TCP/IP). 
     Each hypertext document has an address associated therewith. This address is known as a Uniform Resource Locator (URL). Generally, a user requests hypertext documents using the browser by either typing in the URL, or by maneuvering a cursor to a position on the displayed hypertext document that corresponds to a hyperlink to the URL and actuating the mouse button. The latter method is commonly referred to simply as “clicking on the hot-spot” or “clicking on the hyperlink.” When the user types in the URL or clicks on the hyperlink, the browser transmits the URL corresponding to the requested hypertext document to an HTTP server computer in which the requested hypertext document resides. The server computer retrieves this document and transmits it back to the browser. 
     Although the URL is typically associated with a hypertext document, it may be associated with an executable program instead. If a URL that is associated with an executable program is specified by a browser, the server computer in which the executable program resides executes the program using any input data received from the browser, and the output of the program is transmitted back to the browser, typically in the form of a hypertext document. 
     An in-flight entertainment (IFE) system providing Internet or intranet access is proposed in co-pending U.S. patent application Ser. No. 09/085,180, filed May 26, 1998, entitled “Passenger Entertainment System, Method and Article of Manufacture Having Improved Area Distribution Equipment,” the contents of which are incorporated by reference herein. In this system, client computing capabilities are provided at every seat by equipping each seat with an input device (a passenger control unit and a touch screen), an output device (a display unit), and a processor programmed with a browser. The connection to the Internet is provided by a satellite uplink and downlink. The system may also function as an airborne intranet to permit the passenger to select and control product ordering services, passenger services, and entertainment and communications services without connecting to the Internet. 
     When providing either Internet or intranet access, the above-described system employs a system file server, which is referred to as a cabin file server (CFS) in an IFE system. In the case of Internet access, the CFS functions as a proxy server to manage the connections to other server computers over the Internet. In the case of intranet access, the CFS functions as an HTTP server computer to directly manage requests for hypertext documents and program executions. 
     However, the CFS also functions as the system controller for the IFE system and is programmed to perform other tasks associated with managing the IFE system. As a result, when the CFS is busy with system-related tasks, response rates to a request for hypertext documents and program executions may be unacceptably slow. Also, it is possible that several requests for hypertext documents and program executions may reach the CFS at about the same time. In such a case, the requests will have to be queued, causing further response delays. Further, if the CFS is down for maintenance or repair, the CFS will be unable to process any pending requests until the maintenance or repair has been completed. 
     SUMMARY OF THE INVENTION 
     An object of the invention is to improve the response rates to a request for hypertext documents and program executions in a vehicle entertainment system. 
     Another object of the invention is to decrease the processing load at a system file server of the vehicle entertainment system so that the system file server will have more processing power to perform system-related tasks and manage Internet connections and intranet server functions. 
     Still another object of the invention is to permit passengers of a vehicle entertainment system to select and control passenger, entertainment, and communications services using a browser interface without reliance on either an Internet or intranet connection. 
     The above and other objects of the invention are achieved with a vehicle entertainment system having a system file server connected to a plurality of seat controller cards (SCCs), wherein each SCC is programmed with a browser and an HTTP server program to operate as a server for managing hypertext document requests issued by the browser. When the browser requests hypertext documents that are stored in a local memory of the SCC, the server retrieves the hypertext document from the local memory and provides it to the browser without accessing the system file server for the vehicle entertainment system. As a result, the response rate to a hypertext document request is increased, and the processing load of the system file server is decreased. The decrease in the processing load of the system file server leaves it with more processing power to execute system-related tasks and to perform more effectively as a proxy and/or intranet server. Also, each SCC is considered a micro-network (micronet, for short) because it performs the functions of both the client computer (by being programmed with a browser) and the server computer (by being programmed as an HTTP server). 
     Each SCC is programmed as a micronet because many of the services that are requested using the browser may be handled without connecting to the Internet or accessing the intranet server. For example, when a passenger selects a movie for viewing on his or her display unit through the browser, the SCC provided at his or her passenger seat is tuned to the channel that is carrying the selected movie. The tuning of the SCC to a particular channel is a local task and need not require participation by the system file server either as an Internet proxy server or an intranet server. However, in an IFE system in which the system file server is set up as an Internet proxy server or an intranet server, the request is always transmitted to the system file server and the system file server executes the program for tuning the SCC to the particular channel. In the invention, the SCC is configured as a micrnoet having a browser and a server and the executable program for tuning the SCC resides in the local memory of the SCC, so that the channel selection request made with the micronet browser is carried out locally by the micronet server without involvement by the system file server of the vehicle entertainment system. 
     Additional objects, features and advantages of the invention will be set forth in the description of preferred embodiments which follows. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The various features and advantages of the present invention may be more readily understood with reference to the following detailed description taken in conjunction with the accompanying drawings, and in which: 
     FIG. 1 is a block diagram of a networked IFE system; 
     FIG. 2 illustrates software components of a system file server and a seat controller card of the IFE system according to FIG. 1; 
     FIG. 3 is a block diagram of a seat controller card of the networked IFE system; and 
     FIG. 4 is a diagram illustrating hypertext documents and executable programs that are stored locally in a seat controller card of the networked IFE system. 
    
    
     The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate presently preferred exemplary embodiments of the invention, and, together with the general description given above and the detailed description of the preferred embodiments given below, serve to explain the principles of the invention. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In the description provided below, a description of some of the details of a vehicle entertainment system has been omitted for clarity. Such details may be found in the co-pending U.S. patent application Ser. No. 09/085,180. Further, although an aircraft is depicted, the system according to the invention may be implemented in any vehicle having a passenger entertainment system. Some of the examples include buses, boats, trains, and jetfoils. 
     FIG. 1 is a block diagram of an in-flight entertainment (IFE) system  10  operating in an intranet environment. The intranet server computer includes a cabin file server (CFS)  20  and the client computers include seat controller cards (SCCs)  70  each having a processor  71  (see FIG. 3) that is programmed with a browser and connected to a display  81  and a touch screen  82 . Hypertext documents are displayed on the display  81  and a passenger provides inputs using the touch screen  82 . A RF cable network  55  connects the CFS  20  to the SCCs  70 . 
     In the IFE system  10 , a plurality of micronets are configured within the intranet environment. A micronet is illustrated in FIG.  2 . It constitutes an HTTP connection between a microserver  91 , which operates as the HTTP server program, and a browser  92 , which operates as the HTTP client program. The intranet, by contrast, constitutes an HTTP connection between the CFS  20 , which operates as the intranet server, and the browser  92 . The communications protocol for both the intranet and the micronet is TCP/IP. 
     The microserver  91  and the browser  92  are two software components of the SCC  70 . The microserver  91  constitutes a processor  71  programmed with an HTTP server program and the browser  92  constitutes the processor  71  running an HTTP browser program such as Netscape Navigator and Internet Explorer. The microserver  91  and the browser  92  are preferably stored in a random access memory (RAM)  72   a.    
     The other software components of the SCC  70  include a core application  94  and low-level drivers  95 . The core application  94  includes an operating system for the SCC  70  and an application software for managing the low-level drivers  95 . The low-level drivers  95  control the hardware components of the SCC  70  and external equipment under control of the passenger, such as overhead lights, headphones, attendant call switch, etc. The core application  94  and the low-level drivers are stored in a flash memory  72   b.    
     The RAM  72   a  and the flash memory  72   b  are represented as a memory  72  in FIG.  3 . The RAM  72   a  further stores hypertext documents and executable programs that are managed by the microserver  91 . They include the home page of the microserver  91  with the URL “scc.com/main.htm” and all other hypertext documents and executable programs having the URL “scc.com” as the root address. Some example of such hypertext documents and executable programs are illustrated in FIG.  4 . 
     FIG. 1 also illustrates a media file server  30 , a video modulator  40 , and an area distribution box  50 . The media file server  30  is connected to the CFS  20  by an ethernet connection  25 . When a passenger requests a hypertext document stored and managed by the CFS  20  or the CFS outputs a hypertext document upon executing a program requested by the passenger, the hypertext document is transmitted to the media file server  30  from the CFS  20  over the ethernet connection  25 . The media file server  30  includes quadrature amplitude modulation (QAM) circuit to modulate the transmitted data using QAM to produce QAM radio frequency (RF) signals. The QAM RF signals are then supplied to the video modulator  40  over an RF cable  35 . 
     The video modulator  40  is a device that receives multiple RF inputs and modulates the multiple RF inputs into a single RF signal having multiple RF channels. Only the inputs from the CFS  20  and media file server  30  is shown in FIG. 1 for clarity. The video modulator  40  actually receives multiple inputs from the media file server  30  in addition to other inputs from other devices, such as video cassette players (not shown). The multi-channel RF signal is supplied to the area distribution box  50  over an RF cable  45  and the area distribution box distributes the multi-channel RF signal to the SCCs  70  over the RF cable network  55 . A plurality of attenuators and amplifiers (not shown) are arranged in the RF cable network  55  to automatically optimize signal quality under software control. 
     At the SCCs  70 , a tuner  73  (see FIG. 3) is used to extract a desired channel from the multi-channel RF signal and the extracted signal is either demodulated using an analog demodulator  74  or a QAM demodulator  75 . The demodulated output is supplied to a video card  76  which controls the display  81  to display the demodulated output. In addition to the RF cable network  55 , a token passing bus network  56  using RS-485 protocol, known as ARCNET, is used to pass control signals between the CFS  20  and the SCCs  70 . The ARCNET network  56  is illustrated in FIG. 1 in dotted lines. Through this network, the CFS  20  informs the SCC  70  of the RF channel in which a requested hypertext document or a hypertext output of requested program is contained so that the RF channel can tune to that channel to receive that document. This network  56  is also used to transmit browser requests from the SCC  70  to the CFS  20 . 
     Although the IFE system  10  of FIG. 1 is illustrated as operating in an intranet environment, it may be configured to also have access to the Internet by way of a satellite uplink and downlink in the manner shown in the co-pending U.S. patent application Ser. No. 09/085,180. In such a system, the CFS  20  operates as a proxy server when a URL that is not part of the intranet or the micronet is accessed, e.g., URL that does not have the root address “scc.com” or the root address “cfs.com.” 
     The operation of the IFE system  10  of FIG. 1 will now be explained with reference to FIG.  4 . Upon power-up of the aircraft in which the IFE system  10  is implemented, the hypertext documents and executable programs having the root address “scc.com” are downloaded from the CFS  20  and stored in the RAM  72   a.  Next, the home page of the microserver  91  which has the address “scc.com/main.htm” is displayed on the display  81  to the passenger. The passenger, using the touch screen  82 , specifies a selection from one of shopping, movies, games, audio, and lights, each of which is hyperlinked to a hypertext document. 
     The hypertext document associated with shopping is not resident in the SCC  70  so if the passenger clicks on this hyperlink, a request for the hypertext document “cfs.com/shopping.htm” is issued to the CFS  20  over the ARCNET network  56 . The CFS  20  retrieves this hypertext document and supplies it to the media file server  30  over the ethernet connection  25 . The media file server  30  modulates the requested hypertext document using QAM and supplies the QAM output to the video modulator  40 . The media file server  30  also informs the CFS  20  as to which input channel of the video modulator  40  that it used to supply the QAM output. The multi-channel RF signal including the requested hypertext document in one of the RF channels is generated by the video modulator  40  and distributed to the SCCs  70  by the area distribution box  50  over the RF cable network  55 . The CFS  20  also informs the requesting SCC  70  of the channel containing the requested hypertext document over the ARCNET network  56  and the requesting SCC  70  tunes to that channel, demodulates the RF signal received over that channel, and displays the requested hypertext document. 
     If, on the other hand, the passenger clicks on a hyperlink associated with movies, games, audio, or lights, the hypertext document request is issued over the micronet to the microserver  91 . For example, if the hypertext document associated with movies is requested, the browser  92  sends that request to the microserver  91 , which retrieves the requested hypertext document from the RAM  72   a  and transmits it over the micronet back to the browser  92  for display. Upon display of the hypertext document “scc.com/movies.htm,” the passenger is prompted with a selection between two movies, “Star Wars” and “A Bug&#39;s Life.” Each selection has an executable program associated therewith. The executable programs are also stored in the RAM  72   a.  If “A Bug&#39;s Life” is selected, the browser sends a request to execute the URL “scc.com/cgi/bugs.exe” over the micronet to the microserver  91 . The microserver  91  retrieves the program “scc.com/cgi/bugs.exe” and executes it to cause the tuner  73  to tune to the channel playing that movie. Also, a hypertext document may be generated and returned to the browser  92  over the micronet to display a confirmation message. 
     Similarly, if the hypertext document associated with games is requested, the browser  92  sends that request to the microserver  91 , which retrieves the requested hypertext document from the RAM  72   a  and transmits it over the micronet back to the browser  92  for display. Upon display of the hypertext document “scc.com/games.htm,” the passenger is prompted with a selection between two games, “PGA Tour &#39;99” and “Super Mario.” Each selection has an executable program associated therewith. The executable programs are also stored in the RAM  72   a.  If “PGA Tour &#39;99” is selected, the browser sends a request to execute the URL “scc.com/cgi/pga99.exe” over the micronet to the microserver  91 . The microserver  91  retrieves the program “scc.com/cgi/pga99.exe” and executes a series of program instructions to download the game software into memory  72  and start the game software. Also, a hypertext document may be generated and returned to the browser  92  over the micronet to display a confirmation message. 
     If the hypertext document associated with audio is requested, the browser  92  sends that request to the microserver  91 , which retrieves the requested hypertext document from the RAM  72   a  and transmits it over the micronet back to the browser  92  for display. Upon display of the hypertext document “scc.com/audio.htm,” the passenger is prompted with a selection between “Volume Up” and “Volume Down.” Each selection has an executable program associated therewith. The executable programs are also stored in the RAM  72   a.  If “Volume Up” is selected, the browser sends a request to execute the URL “scc.com/cgi/volup.exe” over the micronet to the microserver  91 . The microserver  91  retrieves the program “scc.com/cgi/volup.exe” and executes a series of program instructions to increase the volume on the headset. Also, a hypertext document may be generated and returned to the browser  92  over the micronet to display a confirmation message. Similarly if “Volume Down” is selected, the microserver  91  executes a series of program instructions to decrease the volume on the headset. 
     If the hypertext document associated with lights is requested, the browser  92  sends that request to the microserver  91 , which retrieves the requested hypertext document from the RAM  72   a  and transmits it over the micronet back to the browser  92  for display. Upon display of the hypertext document “scc.comllights.htm,” the passenger is prompted with a selection between “ON” and “OFF.” Each selection has an executable program associated therewith. The executable programs are also stored in the RAM  72   a.  If “ON” is selected, the browser sends a request to execute the URL “scc.com/cgi/lon.exe” over the micronet to the microserver  91 . If “OFF” is selected, the browser sends a request to execute the URL “scc.com/cgi/loff.exe” over the micronet to the microserver  91 . The microserver  91  retrieves the appropriate program and executes a series of program instructions to turn ON or OFF the overhead light. Also, a hypertext document may be generated and returned to the browser  92  over the micronet to display a confirmation message. 
     A description of a single SCC  70  and a single micronet resident in the SCC  70  has been provided above for clarity. The description of the single SCC  70  and its respective micronet is, however, representative of all other SCCs  70  of the IFE system  10 . When all of the SCCs  70  are considered, the resulting IFE system  10  will include a plurality of micronets interconnected over the RF cable and ARCNET networks  55 ,  56 . Also, each SCC  70  will have its own unique address. The URLs of the different SCCs  70  may be distinguished from one another by using a numerical suffix “###” to form the address “scc###.com.” 
     While particular embodiments according to the invention have been illustrated and described above, it will be clear that the invention can take a variety of forms and embodiments within the scope of the appended claims.