Patent Document

CROSS-REFERENCE TO RELATED APPLICATIONS 
   This patent application is a continuation of U.S. patent application Ser. No. 09/344,389, filed Jun. 25, 1999, now U.S. Pat. No. 6,484,176 issued Nov. 19, 2002, the priority date of which is claimed and the disclosure of which is incorporated by reference. 

   FIELD OF THE INVENTION 
   The present invention relates in general to remote database access and, in particular, to a system and method for transacting retrieval of real estate property listings using a remote client interfaced over an information network. 
   BACKGROUND OF THE INVENTION 
   In the residential segment of the real estate industry, computerized real estate information databases, known as multiple listing service (MLS) databases, have become the premier source of centralized real estate property listing information. MLS databases enjoy widespread acceptance throughout the industry. Individual real estate agencies subscribe to the MLS and provide information about properties both listed and sold. Access is ordinarily restricted to licensed real estate professionals, appraisers, and lending institutions. 
   Typically, an MLS database contains a set of property listing records describing real estate properties being offered for sale, leasing, or rental for a defined geographic region. Each listing identifies and describes the various characteristics of the property in a standard, pre-defined format, which can be easily and accurately searched. Listings can also include maps and photographs of the property. The characteristics also include mortgage rate, pricing and tax information, including the price and terms at which a particular property sold. 
   One important aspect of MLS databases is the ability to archive historical information about properties already sold for use by a broad audience. For instance, to a potential seller or purchaser, historical information is crucial in determining the price at which a comparable property would sell in a particular market segment. Similarly, to an appraiser, historical information is essential in arriving at an appropriate appraisal figure. In an active real estate market, near real time historical information is almost a requirement. 
   Another important aspect of MLS databases is the capability of providing access to new or updated listing information. Most MLS databases are updated continuously. However, as a practical matter, real estate agents do not have continuous access to their respective MLSs. Consequently, real estate agents, and therefore, their clients, generally only learn about new or updated listings during an MLS database access session conducted at the agents&#39; office. 
   One prior art approach to providing access to an MLS is through a remote terminal session. Typically, a terminal or a personal computer configured with a terminal emulator connects to the MLS database either over a dedicated line or via a dial up connection with a modem. The listing information is served in a character-based, page display format, generally consisting of a 25 by 80 character presentation space. Thus, the terminal or personal computer must provide a sufficient screen size upon which to view the listing information, one page at a time. Moreover, access to historical information and new or updated listings can only be obtained during a given access session. 
   A similar prior art approach to providing access to an MLS is the MLSWindows product, described in “WyldFyre Technologies, Inc., Leading the Way In Real Estate GUI Software,” Real Innovators, pp. 18-20 (Summer 1997 ed.). Unlike the conventional terminal screen-based approach, the MLSWindows product provides a graphical user interface (GUI) for viewing listing information, including maps. The MLSWindows product also provides a capability to connect to an MLS database via a TCP/IP network or via synchronous or asynchronous communications. However, the MLSWindows product requires a personal computer with a windowing environment upon which to operate. Although significant progress has been made in miniaturizing portable personal computers, at best, these systems suffer from limited battery life and require a size and weight that make handheld operation impracticable. 
   Therefore, there is a need for a highly portable and flexible solution for remotely accessing a real estate information database in an interactive fashion. Preferably, such a solution includes a capability to automatically be notified of or inquire into new or updated listings. 
   There is a further need for an approach to remotely accessing a real estate information database using a portable computing device which could be standalone or integral to a portable information or communication appliance, such as a wireless communications device. 
   SUMMARY OF THE INVENTION 
   The present invention provides a system and method for transacting retrieval of real estate property listings using a remote client interfaced over an information network. 
   An embodiment of the present invention is a system and method for transacting retrieval of real estate property listings using a remote client interfaced over an information network. A portable computing device maintains both program code and data exclusively in a general purpose random access memory configured for both transient and persistent storage of program code and data. A database server includes a search engine configured to retrieve listing records from a real estate information database. Each listing record includes a set of characteristics describing an individual real estate property listing. A remote client defines methods in the general purpose random access memory for accessing the real estate information database through the search engine. The methods include a session manager, a search specification method, and a search results display method. The session manager facilitates a dynamic session between the portable computing device and the database server over a communications link. The session manager identifies the remote client to the database server and manages an interactive search session between the remote client and the search engine. The search specification method interactively sends to the search engine search parameters and receives from the search engine the listing records having real estate property listing characteristics matching the search parameters. The search results display method displays the received listing records on the portable computing device. 
   A further embodiment of the invention is a portable computing device, process, and computer-readable storage medium holding code for providing remote interactive access to a real estate information database. A general purpose random access memory exclusively maintains both program code and data for both transient and persistent storage. A remote client is configured in the general purpose random access memory and includes methods for accessing a real estate information database through a search engine running on a database server. The search engine is configured to retrieve one or more listing records from the real estate information database with each listing record in the real estate information database including a set of characteristics describing an individual real estate property listing. The remote client includes a session manager facilitating a dynamic session between the portable computing device and the database server over a communications link. The session manager identifies the remote client to the database server and manages an interactive search session between the remote client and the search engine. A search method interactively sends to the search engine search parameters including real estate property listing characteristics and receives from the search engine listing records having characteristics matching the search parameters. A display method displays the listing records on the portable computing device. 
   The present invention facilitates highly portable, interactive access sessions between a portable computing device and a real estate information database, such as an MLS database. The portable computing device can communicate with the real estate information database using a wide range of communication configurations, including a wireless modem, direct dial-up modem, internetwork protocol (IP) modem, and others. A local server could be introduced to continuously transact an access session with the real estate information database and to provide updates to the portable computing device on a regular basis. Similarly, the portable computing device could be configured for automatic update via an express request (pull) or a page (push). 
   Still other embodiments of the present invention will become readily apparent to those skilled in the art from the following detailed description, wherein is described embodiments of the invention by way of illustrating the best mode contemplated for carrying out the invention. As will be realized, the invention is capable of other and different embodiments and its several details are capable of modifications in various obvious respects, all without departing from the spirit and the scope of the present invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not as restrictive. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIGS. 1A and 1B  are block diagrams showing a system for transacting retrieval of real estate property listings using a remote client interfaced over an information network in accordance with the present invention; 
       FIG. 2  is a block diagram showing a further embodiment of the present invention introducing a local server into the system of  FIG. 1A ; 
       FIG. 3  is a functional block diagram showing the remote client used in the system of  FIG. 1A ; 
       FIGS. 4A and 4B  are flow diagrams showing a process for transacting retrieval of real estate property listings using a remote client interfaced over an information network in accordance with the present invention; 
       FIG. 5  is a screen shot showing, by way of example, a preferences specification screen generated by the method of  FIGS. 4A and 4B ; 
       FIGS. 6A and 6B  are screen shots showing, by way of example, a search parameter specification screen and a search status screen generated by the method of  FIGS. 4A and 4B ; 
       FIG. 7  is a screen shot showing, by way of example, search results screen generated by the method of  FIGS. 4A and 4B ; 
       FIG. 8  is a flow diagram showing a routine for initializing a remote client for use in the method of  FIGS. 4A and 4B ; 
       FIG. 9  is a flow diagram showing a routine for executing a search for use in the method of  FIGS. 4A and 4B ; 
       FIG. 10  is a flow diagram showing a routine for executing a detail search for use in the method of  FIGS. 4A and 4B ; 
       FIG. 11  is a flow diagram showing a routine for displaying detailed search results for use in the method of  FIGS. 4A and 4B ; 
       FIGS. 12A-12E  are screen shots showing, by way of example, search result details screens generated by the routine of  FIG. 11 ; 
       FIG. 13  is a flow diagram showing a routine for a paging module which provides a “push” notification as a further embodiment of the present invention; and 
       FIG. 14  is a flow diagram showing a routine for a daemon method for periodically providing a “pull” notification as a further embodiment of the present invention. 
   

   DETAILED DESCRIPTION 
     FIG. 1A  is a block diagram showing a system  7  for providing remote interactive access to a real estate information database  14  (database) using a portable computing device (PCD)  9  in accordance with the present invention. There are two principal sets of components: the PCD  9  and a real estate information system  8 . The real estate information system  8  includes a database server  12  operatively coupled to the database  14 . As further described below, the database server  12  includes a random access memory (RAM) (not shown) into which is loaded and executed a search engine  13 . The search engine  13  interfaces to the database  14  for the storage, retrieval, and searching of listing records stored within the database  14 . In addition, the database server  12  includes serial ports (not shown), a modem bank  21  and a network hub  25 . 
   As also further described below, the PCD  9  is a special purpose computing device and includes a single general purpose RAM  10  configured for both transient and persistent storage of both program code and data. The RAM  10  is used exclusively by the PCD  9  for both program code and data storage, although the operating system, core libraries, and configuration information could be stored in a specialized read only memory (ROM) (not shown), as is known in the art. A remote client  11  (RC) is loaded and executed in the RAM  11  for interactively accessing the real estate information database  14 , as further described below with reference to  FIG. 3 . 
   The PCD  9  can be connected to the database server  12  via three types of communications links. First, the PCD  9  can be directly interfaced to a serial port of the database server  12  using a serial connection  15 . Second, the PCD  9  can be connected to the database server  12  through a wireless server  18 , which is the preferred mode in connection. With this type of communication link, the PCD  9  can be equipped with a wireless modem (not shown) which transmits to a receiver  17  coupled to the wireless server using a radio frequency connection  16 . Alternatively, the PCD  9  can be equipped with a conventional modem and an adapter for connection to a cellular telephone. In turn, the wireless server  18  is equipped with a modem  19  that is interconnected with the modem bank  21  via a modem link  20 . Finally, the PCD  9  can be connected to the database server  12  via a network  23 , such as an internetwork, including the Internet, or an intranetwork. The PCD  9  is connected to the network  23  via a network link  22 , which could be via analog modem, internetwork protocol (IP) modem, wireless modem, and the like. In turn, the network  23  is connected to the network hub  25  of the database server  12  via a high speed network link  24 . 
   The database server  12  is a general purpose, programmed digital computing device consisting of a central processing unit (CPU), RAM, nonvolatile secondary storage, such as a hard drive or CD ROM drive, network interfaces, and peripheral devices, including user interfacing means, such as a keyboard and display. Program code, including software programs, and data are loaded into the RAM for execution and processing by the CPU and results are generated for display, output, transmittal, or storage. In the described embodiment, the database server  12  is a legacy-type data processing system consisting of a traditional mainframe computer system, such as manufactured by Tandem Computers, Inc., Cupertino, Calif. 
   The database system  8  provided by the RE InfoLink Multiple Listing Service, Santa Clara, Calif., is a typical multiple listing service database form. The database  14  includes a set of listing records which each contain a set of characteristics describing the real estate property listing. There are ten classes of properties: single family residential, common interest development, multi residential, mobile homes, residential lots and lands, commercial lots and lands, commercial/industrial, business opportunity, commercial rental, and residential rental. Within each class, a listing record includes various sets of characteristics, including characteristics pertaining to interior, exterior, additional information, including mortgage rate, pricing and tax information, and remarks. Within each of these sets of characteristics, further specifics can be specified, such as, for an interior, type, style, bedrooms, bathrooms, and so on. The database  14  can be searched by specifying these individual characteristics. 
   The PCD  9  is a special purpose, programmed digital computing device consisting of a CPU, the single general purpose RAM, and limited peripheral devices, including a communications port and user interfacing means, such as a data input interface and display. Typically, these devices are highly portable and are designed for handheld use. The primary difference between a conventional computer system and a PCD is the storage subsystem: to conserve on battery life, size and weight, a single general purpose RAM is used for substantially all program code and data storage, instead of using non-volatile secondary storage. The RAM can include conventional dynamic and static access memory devices, as well as flash memory and related electronic integrated circuit storage technologies, as would be recognized by one skilled in the art. In the described embodiment, the PCD  9  is a personal data assistant (PDA), such as the Palm III connected organizer, or any similar member of the Palm connected organizer family, manufactured by 3Com Corporation, Santa Clara, Calif. An exemplary wireless modem is the Ricochet modem, provided along with the Ricochet mobile Internet access service, by Metricom, Inc., Los Gatos, Calif. An alternate PDA that has in integral wireless modem is the Palm VII connected organizer, also manufactured by 3Com Corporation. A cellular telephone modem adapter suitable for use with a Palm III connected organizer is the Snap-On GSM Modem Adapter, manufactured by Option International, Leuven, Belgium. 
   The PCD  9  could also be a handheld personal computer (HPC) running the Windows CE operating system, such as the Cassiopeia HPC, manufactured by Casio Computer Company Ltd., Tokyo, Japan; the Compaq Aero 8000 HPC, manufactured by Compaq Computer, Houston, Tex.; and the Jornada HPC, manufactured by the Hewlett-Packard Company, Palo Alto, Calif. Other types of personal computing devices are feasible. 
   Finally, the PCD  9  could be incorporated as part of the new generation of cellular telephones, known as Smart Phones and similar devices, which integrate the functionality of a PDA with the features of a cellular telephone. The PDQ telephone, manufactured by Qualcomm, San Diego, Calif., in particular incorporates the Palm operating system and connected organizer into a cellular telephone. These types of devices export an application programming interface (API) for interfacing telephony features with client functionality. Thus, the remote client  11  can be loaded and executed using one of these cellular telephones and the database server  12  interactively accessed through the wireless connection afforded by the cellular telephone. 
     FIG. 1B  is a block diagram showing a system  7  for providing remote interactive access to multiple real estate information systems  5   a ,  5   b ,  5   c  using the PCD  9  of  FIG. 1A . The PCD  9  can be connected to any number of real estate information systems  5   a ,  5   b ,  5   c  using either the same or different type of communications link  6   a ,  6   b ,  6   c , respectively. Each communications link  6   a ,  6   b ,  6   c  could be any of the three types of communications links described above with reference to  FIG. 1A , that is, a serial connection, a wireless connection, or a network connection, through various protocol configurations of the remote client  11 , further described below with reference to  FIG. 3 . Preferably, the PCD  9  is only connected to one real estate information system  5   a ,  5   b ,  5   c  at one time. 
     FIG. 2  is a block diagram showing a further embodiment  26  of the present invention introducing a local server  27  into the system  7  of  FIG. 1A . The local server includes a network hub  29  and a random access memory (RAM) (not shown) into which is loaded and executed a paging module  28 . As further described below with reference to  FIG. 13 , the paging module  28  provides a “push” notification of a new or changed real estate property listing to a remote PCD  9  on a regularly scheduled basis. The local server  27  and database server  12  are both connected to a network  31  via high speed network link  30  using network hubs  29  and  25 , respectively. 
     FIG. 3  is a functional block diagram showing the remote client  11  used in the system  8  of  FIG. 1A . The remote client  11  is a computer program written as source code in a conventional programming language, such as the C or Java programming languages, and is presented for execution by the CPU as object or byte code, as is known in the art. The various implementations of the source code and object and byte codes can be held on a computer-readable storage medium, including the general purpose RAM  10  of the PCD  9 , or embodied on a transmission medium in a carrier wave. In the described embodiment, the remote client is written in the C programming language with the Code Warrior C compiler and 3Com Macintosh System Development Kit for the Palm 3.0 operating system. 
   The remote client  11  consists of three primary modules: session manager  32 , search method  33 , and display method  34 . The session manager  32  provides the low level communications interface to the database server  12 , including identifying the remote client  11  and managing an on-going interactive session between the remote client  11  and the search engine  13 . The search method  33  processes search queries by sending sets of search parameters  35  to the search engine  13  via the session manager  32 . In response, the search method  33  receives back search results  36  in the form of real estate property listing records that the search engine  13  has retrieved from the database  14 . Finally, the display method  34  displays the real estate property listing records to the user. The steps performed by the respective modules of the remote client  11  are further described below beginning with reference to  FIGS. 4A and 4B . 
   In one embodiment, the remote client  11  interfaces directly to the search engine  13 . The search results  36  are pre-filtered into a format designed for presentation within the limited size of the display of the PCD  9 . In an alternate embodiment, the search results  36  are returned in a page display format, such as would be acceptable for viewing on a conventional personal computer display. The session manager  32  stores these search results  36  into a receive buffer  37  configured in the general purpose RAM of the PCD  9 . A parser  38  reads in the page display formatted search results from the receive buffer  37  and breaks the search results down into “tokens” for use by the display method  34 . 
   In a further embodiment of the present invention, the remote client  11  includes a daemon method  39  for periodically providing a “pull” notification of a new or changed real estate property listing, as further described below with reference to  FIG. 14 . An alert timer  40  within the daemon method  39  “wakes up” the PCD  9  and initiates a connection to the database server  12 . The search method  33  issues a new query to the search engine  13  and processes any new or changes search results received from the database server  12 . 
     FIGS. 4A and 4B  are flow diagrams showing a process  41  for providing remote interactive access to a real estate information database  14  using a PCD  9  in accordance with the present invention. First, a set of preferences for the interactive session is set (block  42 ). Referring to  FIG. 5 , a screen shot of a preferences specification screen  60  generated, by way of example, by the method  41  of  FIGS. 4A and 4B  is shown. In the described embodiment, four preferences need be specified, a Department of Real Estate (DRE) license number  61 , a password  62 , a phone number  63  and a modem initialization string  64 , although other preferences are also feasible. Upon the completion of the specification of preferences, the preferences can be saved by pressing the virtual “Save” button  65  or discarded by pressing the virtual “Cancel” button  66 . 
   Referring back to  FIGS. 4A and 4B , next, the remote client  11  is initialized (block  43 ) for serial communications by the session manager  32  (shown in  FIG. 3 ) as further described below with reference to  FIG. 8 . A set of search parameters  35  is specified (block  44 ) using the search method  33  (shown in  FIG. 4 ). Referring to  FIG. 6A , a screen shot of a search parameter specification screen  70  generated, by way of example, by the method  41  of  FIGS. 4A and 4B  is shown. In the described embodiment, four search parameters need be specified, a search area or neighborhood  71 , a class  72 , such as “Single Family Residential,” the status of the property  73 , such as “Active,” and a “Search By” characteristics  74 . Here, a pull down menu of characteristics  74  is presented. The search parameters  35  correspond to the set of characteristics describing the real estate property listings stored in the database  14 . Upon the completion of the specification of search parameter specification, the search can be initiated by pressing the virtual “Search” button  75  or more search parameters specified by pressing the virtual “More” button  76 . Referring to  FIG. 6B , a screen shot of a search status screen  66  generated, by way of example, by the method  41  of  FIGS. 4A and 4B  is shown. The number of successful search matches  67  is indicated. The search can be canceled by pressing the virtual “Cancel” button  68 . 
   Referring back to  FIGS. 4A and 4B , a search is executed (block  45 ), as further described below with reference to  FIG. 7 . Search results  36  (shown in  FIG. 3 ) are received (block  46 ). If the search results  36  indicate a match between the search parameters  35  and one or more listing record in the database  14  (block  47 ), the search results  36  are displayed (block  48 ). Referring to  FIG. 7 , a screen shot of a search results screen  80  generated, by way of example, by the method  41  of  FIGS. 4A and 4B  is shown. The search results  36  are displayed as a simple list of properties  81 . 
   Referring back to  FIGS. 4A and 4B , if there is no match (block  47 ), further search parameters  35  can be specified (block  44 ) and the search and review process (blocks  45 - 47 ) repeated. Select search results  36  can be saved for later review (block  49 ) using, for instance, check boxes next to each of the search results  36 . If more details of a found property listing are requested (block  50 ), a detailed search request is executed (block  51 ), as further described below with reference to  FIG. 10 . Otherwise, if details are not requested (block  50 ), a new search can be specified (block  44 ) and the search and review process (blocks  45 - 47 ) repeated. Finally, the detailed search results are received (block  52 ) and displayed (block  53 ), as further described below with reference to  FIG. 12 . The process  41  then ends. 
     FIG. 8  is a flow diagram showing the routine  42  for initializing the remote client  11  for use in the method  41  of  FIGS. 4A and 4B . The purpose of this routine is to prepare the session manager  32  for an interactive serial communications session with the database server  12 . First, the receive buffer  37  (shown in  FIG. 3 ) is allocated (block  90 ). A search parameter structure is allocated for storing the search parameters  35  (block  91 ). A receives parameters structure is allocated for storing the search results  36  (block  92 ). The receive parameters structure can include a data structure for use in reading page display formatted search results stored in the receive buffer  37 . Next, a serial library is allocated (block  94 ). The modem parameters are initialized (block  95 ), such as baud rate, data bits, and parity bits. Finally, the serial port is opened (block  96 ) and a session with the database server  12  is initiated. The routine  42  then returns. 
     FIG. 9  is a flow diagram showing the routine  45  for executing a search for use in the method  41  of  FIGS. 4A and 4B . The purpose of this routine is to send the search parameters  35  to the search engine  13 . If the remote client  11  is not connected to the database server  12  (block  100 ), a connection is initiated (block  101 ). Once connected, the search parameters  35  are sent (block  102 ). In the described embodiment, the remote client  11  interacts with the search engine  13  in two ways. First, using a modem access proxy, such as via a wireless connection, the search parameters  35  are sent to the search engine  13  as if remote client  11  were a conventional character-based terminal. The search results  36  are returned in a page display format, which is then parsed, into tokens by the parser  38  (shown in  FIG. 3 ). Second, the search method  33  invokes a remote function call to the search engine  13  and the search parameters  35  are sent as function call parameters. For example, a Structured Query Language (SQL) or Extensible Markup Language (XML) function call could be used. Upon completion of the sending of the search parameters  35 , the routine  45  returns. 
     FIG. 10  is a flow diagram showing the routine  49  for executing a detail search for use in the method  41  of  FIGS. 4A and 4B . The purpose of this routine is to send a further request for more detailed information about one or more particular property listings from the set of search results  36 . If the remote client  11  is not connected to the database server  12  (block  110 ), a connection is initiated (block  111 ). Once connected, detailed search parameters are sent (block  112 ). In the described embodiment, each listing record describing a real estate property listing in the database  14  includes a unique identifier, called an MLS number. Unique identifiers for particular properties, such as those shown in the example properties list  81  (shown in  FIG. 7 ), are sent to the search engine  12  to retrieve specific detailed information. Upon completion of the sending of the detailed information request, the routine  49  returns. 
     FIG. 11  is a flow diagram showing the routine  51  for displaying detailed search results for use in the method of  FIGS. 4A and 4B . The purpose of this routine is to present detailed property listing information in a user-friendly format on the limited display area of the PCD  9 . First, the detailed listing is displayed (block  120 ). Additional listings can be reviewed (block  121 ) by pressing appropriate navigation virtual buttons. Finally, more detailed information can be shown (block  122 ). Referring to  FIGS. 12A-12E , screen shots showing search result details screens  130 ,  135 ,  140 ,  145 ,  150  generated by the routine  51  of  FIG. 11  are shown. Per screen  130 , detailed listing information  131  is presented. Additional property listings can be accessed by pressing the “→” virtual button  132 . The previous search screen can be accessed by pressing the “Back” virtual button  133 . Per screen  135 , office information  136  is presented. Additional property listings can be accessed by pressing the “→” virtual button  137 . The previous search screen can be accessed by pressing the “Back” virtual button  138 . Per screen  140 , financial information  141  is presented. Additional property listings can be accessed by pressing the “→” virtual button  142 . The previous search screen can be accessed by pressing the “Back” virtual button  143 . Per screen  145 , other information  146  is presented. Additional property listings can be accessed by pressing the “→” virtual button  147 . The previous search screen can be accessed by pressing the “Back” virtual button  148 . Finally, per screen  150 , comments  151  are presented. Additional property listings can be accessed by pressing the “→” virtual button  152 . The previous search screen can be accessed by pressing the “Back” virtual button  153 . Upon completion of the displaying of the detailed information, the routine  51  returns. 
     FIG. 13  is a flow diagram showing a routine for a paging module  160  which provides a “push” notification as a further embodiment of the present invention. This routine operates in the paging module  28  in the remote server  27  (shown in  FIG. 2 ). The paging module  28  is periodically waken up (block  161 ) using an internal timer. If there are new or changed listing records in the database  14  (block  162 ), a Short Messaging Service (SMS) message is sent to the remote client  9  (block  163 ). SMS messages are short alphanumeric messages limited to around 200 characters. Other messaging technologies could also be used, including the Wireless Markup Language (WML), Wireless Application Protocol (WAP), and other related push-type notification protocols, as would be recognized by one skilled in the art. The method  160  then returns to sleep (block  164 ) until the next periodic awakening. The sleeping period can be set to any reasonable interval, such as one hour. 
     FIG. 14  is a flow diagram showing a routine for a daemon method  170  for periodically providing a “pull” notification as a further embodiment of the present invention. The remote client  9  is periodically waken up (block  171 ) using the alert timer  40  (shown in  FIG. 3 ). A connection to the database server  12  is initiated (block  172 ) and a search query is issued to the search engine  13  (block  173 ). If there are new or changed listing records in the database  14  (block  174 ), the search results  36  are received and displayed (block  175 ). The method  170  then returns to sleep (block  176 ) until the next periodic awakening. The sleeping period can be set to any reasonable interval, such as one hour. 
   The present invention provides a highly portable solution to providing remote, interactive access to an real estate information database. This approach provides multiple means of connecting to the real estate information database, including via a direct connection, using a proxy or local server, and via a network connection. In addition, the search method is flexible and provides can interact with the search engine either as a pseudo terminal or using remotely invoked function calls. 
   Moreover, the present invention is based on a portable computing device which differs from personal computer-based solutions by efficiently relying upon a single primary storage subsystem within which both program code and data are stored and executed. This approach provides the practical benefits of dramatically increased battery life, low weight, and minimal form factor. Moreover, the capability to be integrated into a variety of information and communication appliances, such as intelligent and PDQ cellular telephones. 
   While the invention has been particularly shown and described as referenced to the embodiments thereof, those skilled in the art will understand that the foregoing and other changes in form and detail may be made therein without departing from the spirit and scope of the invention.

Technology Category: 3