System and method for pushing information from a host system to a mobile data communication device

Abstract

A system and method for pushing information from a host system to a mobile data communication device upon sensing a triggering event is provided. A redirector program operating at the host system enables a user to continuously redirect certain user-selected data items from the host system to the user's mobile data communication device upon detecting that one or more user-defined triggering events has occurred. The redirector program operates in connection with event generating applications and repackaging systems at the host system to configure and detect a particular user-defined event, and then to repackage the user-selected data items in an electronic wrapper prior to pushing the data items to the mobile device. Included in the system is a program to manage information moved by the user within the host system or the mobile data communication device so that the move is made on both the host system and the mobile data communication device.

Description

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention is directed toward the field of replicating information from a host system where the information is normally stored to a mobile data communication device. In particular, the system and method of the present invention provide an event-driven redirection computer program (“redirector program”) operating at the host system, which, upon sensing a particular user-defined event has occurred, redirects user-selected data items from the host system to the user's mobile data communication device. The mobile data communication device is preferably coupled to the host system via a wireless network and one or more landline networks. Due to the bandwidth limitations of wireless networks, only a portion of a user-selected data item is generally redirected to the user's mobile device, with the user given the option of then retrieving the entire data item (or some other portion of the data item) from the host system.

[0004] Instead of warehousing (or storing) the user's data items at the host system and then “synchronizing” the mobile data communication device to data items stored at the host system when the mobile device requests that such items of information be communicated to it, the present invention employs a “push” paradigm that continuously packages and retransmits the user-selected items of information to the mobile data communication device in response to a triggering event detected at the host system. Wireless mobile data communications devices, especially those that can return a confirmation signal to the host that the pushed data has been received are especially well suited for this type of push paradigm.

[0005] 2. Description of the Related Art

[0006] Present systems and methods for replicating information from a host system to a user's mobile data communication device are typically “synchronization” systems in which the user's data items are warehoused (or stored) at the host system for an indefinite period of time and then transmitted in bulk only in response to a user request. In these types of systems and methods, when replication of the warehoused data items to the mobile device is desired, the user typically places the mobile device in an interface cradle that is electrically connected to the host system via some form of local, dedicated communication, such as a serial cable or an infrared or other type of wireless link. Software executing on the mobile data communication device then transmits commands via the local communications link to the host system to cause the host to begin transmitting the user's data items for storage in a memory bank of the mobile device. In these synchronization schemes, the mobile unit “pulls” the warehoused information from the host system in a batch each time the user desires to replicate information between the two devices. Therefore, the two systems (host and mobile) only maintain the same data items after a user-initiated command sequence that causes the mobile device to download the data items from the host system.

[0007] A general problem with these known synchronization systems is that the only time that the user data items are replicated between the host system and the mobile data communication device is when the user commands the mobile device to download or pull the user data from the host system. Five minutes later a new message could be sent to the user, but the user would not receive that message until the next time the user fetches the user data items. Thus, a user may fail to respond to an emergency update or message because the user only periodically synchronizes the system, such as once per day.

[0008] Other problems with these systems include: (1) the amount of data to be reconciled between the host and the mobile device can become large if the user does not “synchronize” on a daily or hourly basis, leading to bandwidth difficulties, particularly when the mobile device is communicating via a wireless packet-switched network; and (2) reconciling large amounts of data, as can accrue in these batch-mode synchronization systems, can require a great deal of communication between the host and the mobile device, thus leading to a more complex, costly and energy-inefficient system. A more automated, continuous, efficient and reliable system of ensuring that user data items are replicated at the user's mobile device is therefore needed.

SUMMARY OF THE INVENTION

[0009] A system and method of pushing user-selected data items from a host system to a user's mobile data communication device upon detecting the occurrence of one or more user-defined event triggers is provided. As used in this application, the term host system refers to the computer where the redirector software is operating. In the preferred embodiment of the present invention, the host system is a user's desktop PC, although, alternatively, the host system could be a network server connected to the user's PC via a local-area network (“LAN”), or could be any other system that is in communication with the user's desktop PC.

[0010] A redirector program operating at the host system enables the user to redirect or mirror certain user-selected data items (or parts of data items) from the host system to the user's mobile data communication device upon detecting that one or more user-defined triggering events has occurred. Also operating at the host system are various sub-systems that can be configured to create triggering events, such as a screen saver sub-system or a keyboard sub-system, as well as sub-systems for repackaging the user's data items for transparent delivery to the mobile data device, such as a TCP/IP sub-system or one or more E-Mail sub-systems. Other sub-systems for creating triggering events and repackaging the user's data items could also be present at the host system. The host system also includes a primary memory store where the user's data items are normally stored.

[0011] Using the redirector program, the user can select certain data items for redirection, such as E-mail messages, calendar events, meeting notifications, address entries, journal entries, personal reminders, etc. Having selected the data items for redirection, the user can then configure one or more event triggers to be sensed by the redirector program to initiate redirection of the user data items. These user-defined trigger points (or event triggers) include external events, internal events and networked events. Examples of external events include: receiving a message from the user's mobile data communication device to begin redirection; receiving a similar message from some external computer; sensing that the user is no longer in the vicinity of the host system; or any other event that is external to the host system. Internal events could be a calendar alarm, screen saver activation, keyboard timeout, programmable timer, or any other user-defined event that is internal to the host system. Networked events are user-defined messages that are transmitted to the host system from another computer coupled to the host system via a network to initiate redirection. These are just some of the examples of the types of user-defined events that can trigger the redirector program to push data items from the host to the mobile device.

[0012] In addition to the functionality noted above, the redirector program provides a set of software-implemented control functions for determining the type of mobile data communication device and its address, for programming a preferred list of message types that are to be redirected, and for determining whether the mobile device can receive and process certain types of message attachments, such as word processor or voice attachments. The determination of whether a particular mobile device can receive and process attachments is initially configured by the user of that mobile device at the host system. This configuration can then be altered on a global or per message basis by transmitting a command message from the mobile device to the host system. If the redirector is configured so that the mobile data device cannot receive and process word processor or voice attachments, then the redirector routes these attachments to an external machine that is compatible with the particular attachment, such as an attached printer or networked fax machine or telephone. Other types of attachments could be redirected to other types of external machines in a similar fashion, depending upon the capabilities of the mobile device. For example, if a user is traveling and receives a message with an attachment that the user's mobile device can process or display, the user may from a mobile communications device send a command message to the host system indicating that that attachment is to be sent to a fax machine at a hotel where the user will be spending the evening. This enables the user to receive important E-mail attachments as long as the host system is provided with sufficient information about the destination where the attachment is to be forwarded.

[0013] Once an event has triggered redirection of the user data items, the host system then repackages these items in a manner that is transparent to the mobile data communication device, so that information on the mobile device appears similar to information on the user's host system. The preferred repackaging method includes wrapping the user data items in an E-mail envelope that corresponds to the address of the mobile data communication device, although, alternatively, other repackaging methods could be used with the present invention, such as special-purpose TCP/IP wrapping techniques, or other methods of wrapping the user selected data items. The repackaging preferably results in E-mail messages appearing to come from the host system even though they are initiated at the mobile device, thus enabling the user to appear to have a single E-mail address, such that the recipients of messages sent from the mobile communications device do not know where the user was physically located when the message was first sent. The repackaging also permits both messages to the mobile device and sent from the mobile device to be encrypted and decrypted as well as compressed and decompressed.

[0014] In an alternative system and method, the redirector program executes on a network server, and the server is programmed to detect numerous redirection event triggers over the network from multiple user desktop computers coupled to the server via a LAN. The server can receive internal event triggers from each of the user desktops via the network, and can also receive external event triggers, such as messages from the users' mobile data communication devices. In response to receiving one of these triggers, the server redirects the user's data items to the proper mobile data communication device. The user data items and addressing information for a particular mobile device can be stored at the server or at the user's PC. Using this alternative configuration, one redirector program can serve a plurality of users. This alternative configuration could also include an internet- or intranet-based redirector program that could be accessible through a secure webpage or other user interface. The redirector program could be located on an Internet Service Provider's system and accessible only through the Internet.

[0015] In another alternative configuration of the present invention, a redirector program operates at both the host system and at the user's mobile data communication device. In this configuration, the user's mobile device operates similarly to the host system described below, and is configured in a similar fashion to push certain user-selected data items from the mobile device to the user's host system (or some other computer) upon detecting an event trigger at the mobile device. This configuration provides two-way pushing of information from the host to the mobile device and from the mobile device to the host.

[0016] An advantage of the present invention is that it provides a system and method for triggering the continuous and real-time redirection of user-selected data items from a host system to a mobile data communication device. Other advantages of the present invention include: (1) flexibility in defining the types of user data to redirect, and in defining a preferred list of message types that are to be redirected or preferred senders whose messages are to be redirected; (2) flexibility in configuring the system to respond to numerous internal, external and networked triggering events; (3) transparent repackaging of the user data items in a variety of ways such that the mobile data communication device appears as though it were the host system; (4) integration with other host system components such as E-mail, TCP/IP, keyboard, screen saver, webpages and certain programs that can either create user data items or be configured to provide trigger points; and (5) the ability to operate locally on a user's desktop system or at a distance via a network server.

[0017] A further advantage of the present invention is that it provides a software structure and method for managing messages between the mobile data communication device and the host system. The software provides a logical structure for folders and messages that can detect movement of messages between folders on either the mobile data communication device or the host system. This allows the user the flexibility to organize messages into folders on the mobile data communication device without having to replicate the organizational work on the host system, or vice versa. The folder and message software structure further provides the redirector program trigger signals for forwarding messages.

[0018] These are just a few of the many advantages of the present invention, as described in more detail below. As will be appreciated, the invention is capable of other and different embodiments, and its several details are capable of modifications in various respects, all without departing from the spirit of the invention. Accordingly, the drawings and description of the preferred embodiments set forth below are to be regarded as illustrative in nature and not restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] FIG. 1 is a system diagram showing the redirection of user data items from a user's desktop PC (host system) to the user's mobile data communication device, where the redirector software is operating at the user's desktop PC.

[0020] FIG. 2 is a system diagram showing the redirection of user data items from a network server (host system) to the user's mobile data communication device, where the redirector software is operating at the server.

[0021] FIG. 3 is a block diagram showing the interaction of the redirector software with other components of the host system in FIG. 1 (the user's desktop PC) to enable the pushing of information from the host system to the user's mobile data communication device.

[0022] FIG. 4 is a flow chart showing the steps carried out by the redirector software operating at the host system.

[0023] FIG. 5 is a flow chart showing the steps carried out by the mobile data communication device to interface with the redirector software operating at the host system.

[0024] FIG. 6 is a schematic diagram of the logical structure of a folder and a message.

[0025] FIG. 7 is a flow chart showing the steps of synchronizing folders and messages between the host system and the mobile data communication device.

[0026] FIG. 8 is a flow chart showing the steps of assigning IDs to folders.

[0027] FIG. 9 is a flow chart showing the steps of retrieving messages from the store.

[0028] FIGS. 10A and B is a flow chart more specifically showing the steps of synchronizing messages between the host system and the mobile data communication device.

[0029] FIG. 11 is a flow chart showing the steps of attaching a folder ID to a message.

[0030] FIG. 12 is a flow chart showing the steps of moving a message locally on a device.

[0031] FIG. 13 is a flow chart showing the steps of sending a move message to the host system after a message has been moved on the mobile device.

[0032] FIG. 14 is a flow chart showing the steps of sending a move message from the host system to the mobile device after a message has been moved on the host system.

[0033] FIG. 15 is a flow chart showing the steps of acting upon the move message command of FIG. 13 at the device.

[0034] FIG. 16 is a flow chart showing the steps of acting upon the message move command of FIG. 14.

[0035] FIG. 17 is a flow chart showing the steps of deleting a message.

[0036] FIG. 18 is a flow chart showing the steps of purging a message.

[0037] FIG. 19 is a flow chart showing the steps of generating a folder list for redirecting messages received at a store.

[0038] FIG. 20 is a flow chart showing the steps of redirecting a message received and filed in the folder list of FIG. 19.

DETAILED DESCRIPTION OF THE DRAWINGS

[0039] Referring now to the drawings, FIG. 1 is an example system diagram showing the redirection of user data items (such as message A or C) from a user's office PC (host system) 10 to the user's mobile data communication device 24, where the redirector software 12 is operating at the user's PC. Message A in FIG. 1 represents an internal message sent from desktop 26 to the user's host system 10 via LAN 14. Message C in FIG. 1 represents an external message from a sender that is not directly connected to LAN 14, such as the user's mobile data communication device 24, some other user's mobile device (not shown), or any user connected to the Internet 18. Message C also represents a command message from the user's mobile data communication device 24 to the host system 10. As described in more detail in FIG. 3, the host system 10 preferably includes, along with the typical hardware and software associated with a workstation or desktop computer, the redirector program 12, a TCP/IP subsystem 42, a primary message store 40, an E-mail subsystem 44, a screen saver subsystem 48, and a keyboard subsystem 46.

[0040] In FIG. 1, the host system 10 is the user's desktop system, typically located in the user's office. The host system 10 is connected to a LAN 14, which also connects to other computers 26, 28 that may be in the user's office or elsewhere. The LAN 14, in turn, is connected to a wide area network (“WAN”) 18, preferably the Internet, which is defined by the use of the Transmission Control Protocol/Internet Protocol (“TCP/IP”) to exchange information, but which, alternatively could be any other type of WAN. The connection of the LAN 14 to the WAN 18 is via high bandwidth link 16, typically a T1 or T3 connection. The WAN 18, in turn, is connected to a variety of gateways 20, via connections 32. A gateway forms a connection or bridge between the WAN 18 and some other type of network, such as an RF wireless network, cellular network, satellite network, or other synchronous or asynchronous land-line connection.

[0041] In the example of FIG. 1, a wireless gateway 20 is connected to the Internet for communicating via wireless link 22 to a plurality of wireless mobile data communication devices 24. Also shown in FIG. 1 is machine 30, which could be a FAX machine, a printer, a system for displaying images (such as video) or a machine capable of processing and playing audio files, such as a voice mail system. The present invention includes the ability to redirect certain message attachments to such an external machine 30 if the redirector program configuration data reflects that the mobile device 24 cannot receive and process the attachments, or if the user has specified that certain attachments are not to be forwarded to mobile device 24, even if such device can process those attachments. By way of example, consider an E-mail sent to a user that includes three attachments—a word processing document, a video clip and an audio clip. The redirection program could be configured to send the text of the E-mail to the remote device, to send the word processing document to a networked printer located near the user, to send the video clip to a store accessible through a secure connection through the Internet, and to send the audio clip to the user's voice mail system. This example is not intended to limit the breadth and scope of the invention, but rather to illustrate the variety of possibilities embodied in the redirection concept.

[0042] The preferred mobile data communication device 24 is a hand-held two-way wireless paging computer, a wirelessly enabled palm-top computer, a mobile telephone with data messaging capabilities, or a wirelessly enabled laptop computer, but could, alternatively be other types of mobile data communication devices capable of sending and receiving messages via a network connection 22. Although it is preferable for the system to operate in a two-way communications mode, certain aspects of the invention could be beneficially used in a “one and one-half” or acknowledgment paging environment, or even with a one-way paging system. The mobile data communication device 24 includes software program instructions that work in conjunction with the redirector program 12 to enable the seamless, transparent redirection of user-selected data items. FIG. 4 describes the basic method steps of the redirector program 12, and FIG. 5 describes the steps of the corresponding program operating at the mobile device 24.

[0043] In an alternative embodiment of the present invention, not explicitly shown in the drawings, the mobile device 24 also includes a redirector program. In this embodiment, user selected data items can be replicated from the host to the mobile device and vice versa. The configuration and operation of the mobile device 24 having a redirector program is similar to that described herein with respect to FIGS. 1-4.

[0044] A user of the present invention can configure the redirector program 12 to push certain user-selected data items to the user's mobile data communication device 24 when the redirector 12 detects that a particular user-defined event trigger (or trigger point) has taken place. User-selected data items preferably include E-mail messages, calendar events, meeting notifications, address entries, journal entries, personal alerts, alarms, warnings, stock quotes, news bulletins, etc., but could, alternatively, include any other type of message that is transmitted to the host system 10, or that the host system 10 acquires through the use of intelligent agents, such as data that is received after the host system 10 initiates a search of a database or a website or a bulletin board. In some instances, only a portion of the data item is transmitted to the mobile device 24 in order to minimize the amount of data transmitted via the wireless network 22. In these instances, the mobile device 24 can optionally send a command message to the host system to receive more or all of the data item if the user desires to receive it.

[0045] The user-defined event triggers that can be detected by the redirector program 12 preferably include external events, internal events and networked events. External events preferably include: (1) receiving a command message (such as message C) from the user's mobile data communication device to begin redirection, or to execute some other command at the host, such as a command to enable the preferred list mode, or to add or subtract a particular sender from the preferred list; (2) receiving a similar message from some external computer; and (3) sensing that the user is no longer in the vicinity of the host system; although, alternatively, an external event can be any other detectable occurrence that is external to the host system. Internal events could be a calendar alarm, screen saver activation, keyboard timeout, programmable timer, or any other user-defined event that is internal to the host system. Networked events are user-defined messages that are transmitted to the host system from another computer coupled to the host system via a network to initiate redirection. These are just some of the events that could be used with the present invention to initiate replication of the user-selected data items from the host system 10 to the mobile device 24.

[0046] FIG. 1 shows an E-mail message A being communicated over LAN 14 from computer 26 to the user's desktop system 10 (also shown in FIG. 1 is an external message C, which could be an E-mail message from an Internet user, or could be a command message from the user's mobile device 24). Once the message A (or C) reaches the primary message store of the host system 10, it can be detected and acted upon by the redirection software 12. The redirection software 12 can use many methods of detecting new messages. The preferred method of detecting new messages is using Microsoft's ® Messaging API (MAPI), in which programs, such as the redirector program 12, register for notifications or ‘advise syncs’ when changes to a mailbox take place. Other methods of detecting new messages could also be used with the present invention. Assuming that the redirector program 12 is activated, and has been configured by the user (either through the sensing of an internal, network or external event) to replicate certain user data items (including messages of type A or C) to the mobile device 24, when the message A is received at the host system 10, the redirector program 12 detects its presence and prepares the message for redirection to the mobile device 24. In preparing the message A for redirection, the redirector program 12 could compress the original message A, could compress the message header, or could encrypt the entire message A to create a secure link to the mobile device 24.

[0047] Also programmed into the redirector 12 is the address of the user's mobile data communication device 24, the type of device, and whether the device 24 can accept certain types of attachments, such as word processing or voice attachments. If the user's type of mobile device cannot accept these types of attachments, then the redirector 12 can be programmed to route the attachments to a fax or voice number where the user is located using an attached fax or voice machine 30.

[0048] The redirector may also be programmed with a preferred list mode that is configured by the user either at the host system 10, or remotely from the user's mobile data communication device by transmitting a command message C. The preferred list contains a list of senders (other users) whose messages are to be redirected or a list of message characteristics that determine whether a message is to be redirected. If activated, the preferred list mode causes the redirector program 12 to operate like a filter, only redirecting certain user data items based on whether the particular data item was sent from a sender on the preferred list or has certain message characteristics that if present will trigger or suppress redirection of the message.

[0049] In the example of FIG. 1, if desktop system 26 was operated by a user on the preferred list of host system 10, and the preferred list option was activated, then message A would be redirected. If, however, desktop 26 was operated by a user not on the host system's preferred list, then message A would not be redirected, even if the user of the host system had configured the redirector to push messages of type A. The user of the host system 10 can configure the preferred list directly from the desktop system, or, alternatively, the user can send a command message (such as C) from the mobile device 24 to the desktop system 10 to activate the preferred list mode, or to add or delete certain senders or message characteristics from the preferred list that was previously configured. It should be appreciated that a redirection program could combine message characteristics and preferred sender lists to result in a more finely-tuned filter. Messages marked as low priority or that are simple return receipts or message read receipts, for example, could always be suppressed from redirection while messages from a particular sender would always be redirected.

[0050] After the redirector has determined that a particular message should be redirected, and it has prepared the message for redirection, the software 12 then sends the message A to a secondary memory store located in the mobile device 24, using whatever means are necessary. In the preferred embodiment this method is to send the message A back over the LAN 14, WAN 18, and through the wireless gateway 20 to the mobile data communication device 24. In doing so, the redirector preferably repackages message A as an E-mail with an outer envelope B that contains the addressing information of the mobile device 24, although alternative repackaging techniques and protocols could be used, such as a TCP/IP repackaging and delivery method (most commonly used in the alternative server configuration shown in FIG.2). The wireless gateway 20 requires this outer envelope information B in order to know where to send the redirected message A. Once the message (A in B) is received by the mobile device 24, the outer envelope B is removed and the original message A is placed in the secondary memory store within the mobile device 24. By repackaging and removing the outer envelope in this manner, the present invention causes the mobile computer 24 to appear to be at the same physical location as the host system 10, thus creating a transparent system.

[0051] In the case where message C is representative of an external message from a computer on the Internet 18 to the host system 10, and the host 10 has been configured to redirect messages of type C, then in a similar manner to message A, message C would be repackaged with an outer envelope B and transmitted to the user's mobile device 24. In the case where message C is representative of a command message from the user's mobile device 24 to the host system 10, then the command message C is not redirected, but is acted upon by the host system 10.

[0052] If the redirected user data item is an E-mail message, as described above, the user at the mobile device 24 sees the original subject, sender's address, destination address, carbon copy and blind carbon copy. When the user replies to this message, or when the user authors a new message, the software operating at the mobile device 24 adds a similar outer envelope to the reply message (or the new message) to cause the message to be routed first to the user's host system 10, which then removes the outer envelope and redirects the message to the final destination, such as back to computer 26. In the preferred embodiment, this results in the outgoing redirected message from the user's host system 10 being sent using the E-mail address of the host mailbox, rather than the address of the mobile device, so that it appears to the recipient of the message that the message originated from the user's desktop system 10 rather than the mobile data communication device. Any replies to the redirected message will then be sent to the desktop system 10, which if it is still in redirector mode, will repackage the reply and resend it to the user's mobile data device, as described above.

[0053] FIG. 2 is an alternative system diagram showing the redirection of user data items from a network server 11 to the user's mobile data communication device 24, where the redirector software 12 is operating at the server 11. This configuration is particularly advantageous for use with message servers such as Microsoft's ® Exchange Server, which is normally operated so that all user messages are kept in one central location or mailbox store on the server instead of in a store within each user's desktop PC. This configuration has the additional advantage of allowing a single system administrator to configure and keep track of all users having messages redirected. If the system includes encryption keys, these too can be kept at one place for management and update purposes.

[0054] In this alternative configuration, server 11 preferably maintains a user profile for each user's desktop system 10, 26, 28, including information such as whether a particular user can have data items redirected, which types of message and information to redirect, what events will trigger redirection, the address of the users' mobile data communication device 24, the type of mobile device, and the user's preferred list, if any. The event triggers are preferably detected at the user's desktop system 10, 26, 28 and can be any of the external, internal or network events listed above. The desktop systems 10, 26, 28 preferably detect these events and then transmit a message to the server computer 11 via LAN 14 to initiate redirection. Although the user data items are preferably stored at the server computer 11 in this embodiment, they could, alternatively, be stored at each user's desktop system 10, 26, 28, which would then transmit them to the server computer 11 after an event has triggered redirection.

[0055] As shown in FIG. 2, desktop system 26 generates a message A that is transmitted to and stored at the host system 11, which is the network server operating the redirector program 12. The message A is for desktop system 10, but in this embodiment, user messages are stored at the network server 11. When an event occurs at desktop system 10, an event trigger is generated and transmitted to the network server 11, which then determines who the trigger is from, whether that desktop has redirection capabilities, and if so, the server (operating the redirector program) uses the stored configuration information to redirect message A to the mobile computer 24 associated with the user of desktop system 10.

[0056] As described above with reference to FIG. 1, message C could be either a command message from a user's mobile data communication device 24, or it could be a message from an external computer, such as a computer connected to the Internet 18. If the message C is from an Internet computer to the user's desktop system 10, and the user has redirection capabilities, then the server 11 detects the message C, repackages it using electronic envelope B, and redirects the repackaged message (C in B) to the user's mobile device 24. If the message C is a command message from the user's mobile device 24, then the server 11 simply acts upon the command message.

[0057] Turning now to FIG. 3, a block diagram showing the interaction of the redirector software 12 with additional components of the host system 10 of FIG. 1 (the desktop PC) to enable more fully the pushing of information from the host system 10 to the user's mobile data communication device 24 is set forth. These additional components are illustrative of the type of event-generating systems that can be configured and used with the redirector software 12, and of the type of repackaging systems that can be used to interface with the mobile communication device 24 to make it appear transparent to the user.

[0058] The desktop system 10 is connected to LAN 14, and can send and receive data, messages, signals, event triggers, etc., to and from other systems connected to the LAN 14 and to external networks 18, 22, such as the Internet or a wireless data network, which are also coupled to the LAN 14. In addition to the standard hardware, operating system, and application programs associated with a typical microcomputer or workstation, the desktop system 10 includes the redirector program 12, a TCP/IP sub-system 42, an E-mail sub-system 44, a primary data storage device 40, a screen saver sub-system 48, and a keyboard sub-system 46. The TCP/IP and E-mail subsystems 42, 44 are examples of repackaging systems that can be used to achieve the transparency of the present invention, and the screen saver and keyboard sub-systems 46, 48 are examples of event generating systems that can be configured to generate event messages or signals that trigger redirection of the user selected data items.

[0059] The method steps carried out by the redirector program 12 are described in more detail in FIG. 4. The basic functions of this program are: (1) configure and setup the user-defined event trigger points that will start redirection; (2) configure the types of user data items for redirection and optionally configure a preferred list of senders whose messages are to be redirected; (3) configure the type and capabilities of the user's mobile data communication device; (4) receive messages and signals from the repackaging systems and the event generating systems; and (5) command and control the redirection of the user-selected data items to the mobile data communication device via the repackaging systems. Other functions not specifically enumerated could also be integrated into this program.

[0060] The E-Mail sub-system 44 is the preferred link to repackaging the user-selected data items for transmission to the mobile data communication device 24, and preferably uses industry standard mail protocols, such as SMTP, POP, IMAP, MIME and RFC-822, to name but a few. The E-Mail sub-system 44 can receive messages A from external computers on the LAN 14, or can receive messages C from some external network such as the Internet 18 or a wireless data communication network 22, and stores these messages in the primary data store 40. Assuming that the redirector 12 has been triggered to redirect messages of this type, the redirector detects the presence of any new messages and instructs the E-Mail system 44 to repackage the message by placing an outer wrapper B about the original message A (or C), and by providing the addressing information of the mobile data communication device 24 on the outer wrapper B. As noted above, this outer wrapper B is removed by the mobile device 24, and the original message A (or C) is then recovered, thus making the mobile device 24 appear to be the desktop system 10.

[0061] In addition, the E-Mail sub-system 44 receives messages back from the mobile device 24 having an outer wrapper with the addressing information of the desktop system 10, and strips this information away so that the message can be routed to the proper sender of the original message A (or C). The E-Mail sub-system also receives command messages C from the mobile device 24 that are directed to the desktop system 10 to trigger redirection or to carry out some other function. The functionality of the E-Mail sub-system 44 is controlled by the redirector program 12.

[0062] The TCP/IP sub-system 42 is an alternative repackaging system. It includes all of the functionality of the E-Mail sub-system 44, but instead of repackaging the user-selected data items as standard E-mail messages, this system repackages the data items using special-purpose TCP/IP packaging techniques. This type of special-purpose sub-system is useful in situations where security and improved speed are important to the user. The provision of a special-purpose wrapper that can only be removed by special software on the mobile device 24 provides the added security, and the bypassing of E-mail store and forward systems can improve speed and real-time delivery.

[0063] As described previously, the present invention can be triggered to begin redirection upon detecting numerous external, internal and networked events, or trigger points. Examples of external events include: receiving a command message from the user's mobile data communication device 24 to begin redirection; receiving a similar message from some external computer; sensing that the user is no longer in the vicinity of the host system; or any other event that is external to the host system. Internal events could be a calendar alarm, screen saver activation, keyboard timeout, programmable timer, or any other user-defined event that is internal to the host system. Networked events are user-defined messages that are transmitted to the host system from another computer that is connected to the host system via a network to initiate redirection.

[0064] The screen saver and keyboard sub-systems 46, 48 are examples of systems that are capable of generating internal events. Functionally, the redirector program 12 provides the user with the ability to configure the screen saver and keyboard systems so that under certain conditions an event trigger will be generated that can be detected by the redirector 12 to start the redirection process. For example, the screen saver system can be configured so that when the screen saver is activated, after, for example, 10 minutes of inactivity on the desktop system, an event trigger is transmitted to the redirector 12, which starts redirecting the previously selected user data items. In a similar manner the keyboard sub-system can be configured to generate event triggers when no key has been depressed for a particular period of time, thus indicating that redirection should commence. These are just two examples of the numerous application programs and hardware systems internal to the host system 10 that can be used to generate internal event triggers.

[0065] FIGS. 4 and 5, set forth, respectively, flow charts showing the steps carried out by the redirector software 12 operating at the host system 10, and the steps carried out by the mobile data communication device 24 in order to interface with the host system. Turning first to FIG. 4, at step 50, the redirector program 12 is started and initially configured. The initial configuration of the redirector 12 includes: (1) defining the event triggers that the user has determined will trigger redirection; (2) selecting the user data items for redirection; (3) selecting the repackaging sub-system, either standard E-Mail, or special-purpose technique; (4) selecting the type of data communication device, indicating whether and what type of attachments the device is capable of receiving and processing, and inputting the address of the mobile device; and (5) configuring the preferred list of user selected senders whose messages are to be redirected.

[0066] FIG. 4 sets forth the basic steps of the redirector program 12 assuming it is operating at a desktop system 10, such as shown in FIG. 1. If the redirector 12 is operating at a network server 11, as shown in FIG. 2, then additional configuration steps may be necessary to enable redirection for a particular desktop system 10, 26, 28 connected to the server, including: (1) setting up a profile for the desktop system indicating its address, events that will trigger redirection, and the data items that are to be redirected upon detecting an event; (2) maintaining a storage area at the server for the data items; and (3) storing the type of data communication device to which the desktop system's data items are to be redirected, whether and what type of attachments the device is capable of receiving and processing, and the address of the mobile device.

[0067] Once the redirector program is configured 50, the trigger points (or event triggers) are enabled at step 52. The program 12 then waits 56 for messages and signals 54 to begin the redirection process. A message could be an E-Mail message or some other user data item than may have been selected for redirection, and a signal could be a trigger signal, or could be some other type of signal that has not been configured as an event trigger. When a message or signal is detected, the program determines 58 whether it is one of the trigger events that has been configured by the user to signal redirection. If so, then at step 60 a trigger flag is set, indicating that subsequently received user data items (in the form of messages) that have been selected for redirection should be pushed to the user's mobile data communication device 24.

[0068] If the message or signal 54 is not a trigger event, the program then determines at steps 62, 68 and 66 whether the message is, respectively, a system alarm 62, an E-Mail message 64, or some other type of information that has been selected for redirection. If the message or signal is none of these three items, then control returns to step 56, where the redirector waits for additional messages 54 to act upon. If, however the message is one of these three types of information, then the program 12 determines, at step 68, whether the trigger flag has been set, indicating that the user wants these items redirected to the mobile device. If the trigger flag is set, then at step 70, the redirector 12 causes the repackaging system (E-Mail or TCP/IP) to add the outer envelope to the user data item, and at step 72 the repackaged data item is then redirected to the user's mobile data communication device 24 via LAN 14, WAN 18, wireless gateway 20 and wireless network 22. Control then returns to step 56 where the program waits for additional messages and signals to act upon. Although not shown explicitly in FIG. 4, after step 68, the program could, if operating in the preferred list mode, determine whether the sender of a particular data item is on the preferred list, and if not, then the program would skip over steps 70 and 72 and proceed directly back to step 56. If the sender was on the preferred list, then control would similarly pass to steps 70 and 72 for repackaging and transmission of the message from the preferred list sender.

[0069] FIG. 5 sets forth the method steps carried out by the user's mobile data communication device 24 in order to interface to the redirector program 12 of the present invention. At step 80 the mobile software is started and the mobile device 24 is configured to operate with the system of the present invention, including, for example, storing the address of the user's desktop system 10.

[0070] At step 82, the mobile device waits for messages and signals 84 to be generated or received. Assuming that the redirector software 12 operating at the user's desktop system 10 is configured to redirect upon receiving a message from the user's mobile device 24, at step 86, the user can decide to generate a command message that will start redirection. If the user does so, then at step 88 the redirection message is composed and sent to the desktop system 10 via the wireless network 22, through the wireless gateway 20, via the Internet 18 to the LAN 14, and is finally routed to the desktop machine 10. In this situation where the mobile device 24 is sending a message directly to the desktop system 10, no outer wrapper is added to the message (such as message C in FIGS. 1 and 2). In addition to the redirection signal, the mobile device 24 could transmit any number of other commands to control the operation of the host system, and in particular the redirector program 12. For example, the mobile 24 could transmit a command to put the host system into the preferred list mode, and then could transmit additional commands to add or subtract certain senders from the preferred list. In this manner, the mobile device 24 can dynamically limit the amount of information being redirected to it by minimizing the number of senders on the preferred list. Other example commands include: (1) a message to change the configuration of the host system to enable the mobile device 24 to receive and process certain attachments; and (2) a message to instruct the host system to redirect an entire data item to the mobile device in the situation where only a portion of a particular data item has been redirected.

[0071] Turning back to FIG. 5, if the user signal or message is not a direct message to the desktop system 10 to begin redirection (or some other command), then control is passed to step 90, which determines if a message has been received. If a message is received by the mobile, and it is a message from the user's desktop 10, as determined at step 92, then at step 94 a desktop redirection flag is set “on” for this message, and control passes to step 96 where the outer envelope is removed. Following step 96, or in the situation where the message is not from the user's desktop, as determined at step 92, control passes to step 98, which displays the message for the user on the mobile device's display. The mobile unit 24 then returns to step 82 and waits for additional messages or signals.

[0072] If the mobile device 24 determines that a message has not been received at step 90, then control passes to step 100, where the mobile determines whether there is a message to send. If not, then the mobile unit returns to step 82 and waits for additional messages or signals. If there is at least one message to send, then at step 102 the mobile determines whether it is a reply message to a message that was received by the mobile unit. If the message to send is a reply message, then at step 108, the mobile determines whether the desktop redirection flag is on for this message. If the redirection flag is not on, then at step 106 the reply message is simply transmitted from the mobile device to the destination address via the wireless network 22. If, however, the redirection flag is on, then at step 110 the reply message is repackaged with the outer envelope having the addressing information of the user's desktop system 10, and the repackaged message is then transmitted to the desktop system 10 at step 106. As described above, the redirector program 12 executing at the desktop system then strips the outer envelope and routes the reply message to the appropriate destination address using the address of the desktop system as the “from” field, so that to the recipient of the redirected message, it appears as though it originated from the user's desktop system rather than the mobile data communication device.

[0073] If, at step 102, the mobile determines that the message is not a reply message, but an original message, then control passes to step 104, where the mobile determines if the user is using the redirector software 12 at the desktop system 10, by checking the mobile unit's configuration. If the user is not using the redirector software 12, then the message is simply transmitted to the destination address at step 106. If, however, the mobile determines that the user is using the redirector software 12 at the desktop system 10, then control passes to step 110, where the outer envelope is added to the message. The repackaged original message is then transmitted to the desktop system 10 at step 106, which, as described previously, strips the outer envelope and routes the message to the correct destination. Following transmission of the message at step 106, control of the mobile returns to step 82 and waits for additional messages or signals.

[0074] Organizing and storing messages in the mobile device 24 and the host system 10 is set forth in FIGS. 6 through 18. The mobile device 24 preferably includes a hierarchical folder system, as does the host system 10. The user can select from multiple levels of folders to find a certain folder. For example, the user can organize messages into categories such as friends, coworkers, contacts, and “to do” list on the mobile device. Software on the mobile device 24 and the host system 10 organizes the messages so that filing a message on either the mobile device 24 or the host system 10 will be recognized at the other device either by commands sent through the redirector program or by synchronizing the devices. Synchronization can occur, for example, by plugging the mobile device into an interface cradle coupled to the host system.

[0075] FIG. 6 sets forth a preferred message structure 120 and folder structure 130 for messages and folders that are stored on the host system 10 and the mobile device 24. The message structure 120 includes a message body and a message header. The message header includes tags such as a message ID, a parent ID and a folder ID. The message ID is a unique tag that is associated with a single message. The message ID is assigned to a message when the message is received in the store. The parent ID is a tag that contains the unique ID of a parent message. The parent ID can maintain links between messages. The folder ID is a tag that contains the unique ID of the folder in which the message is to be stored.

[0076] The folder structure includes a folder ID, folder type, folder name, and parent folder ID. The folder ID is a unique tag for each folder. The folder ID is generated when the mobile device 24 is synchronized to the host system 10. The type of folder specifies attributes of the folder that differentiate it from other folders. One such folder could be a deleted items folder. The deleted items folder could be set to automatically purge messages after a given time. The folder name is the name of the folder that will be displayed on the device 24 or the host system 10. The parent folder ID is the folder ID of the folder that is one level above the current folder in the hierarchical system.

[0077] FIG. 7 is a flow chart showing the steps of synchronizing folders and messages between the host system 10 and the mobile device 24. Synchronization starts in step 140 when the mobile device 24 is placed in an interface cradle coupled to the host system 10. The folder list is retrieved and tagged in step 142 from a store at the host system 10. In step 144, the mobile device 24 is updated using the list of folders from the store. After the folders on the mobile device are updated 144 to match the folder structures 130 in the host system 10, the messages stored in the host system 10 are retrieved in step 146. The messages in the mobile device 24 are similarly retrieved in step 148. Step 150 compares the unique message IDs of messages in the mobile device 24 and the host system 10 to find similar messages. Once similar messages are found on the mobile device 24 and the host system 10, step 152 determines whether or not a message has been moved within the folder system. When one of the two messages(host message and mobile device message) is determined to have been moved, the other message is moved to the folder that matches the folder ID of the moved message in step 154. All similar messages from the mobile device 24 and the host system 10 are checked to determine 152 where the messages should be placed and moved 154 accordingly.

[0078] The folder structure synchronization process 136 first synchronizes the folder hierarchy of the mobile device 24 to the hierarchy of the host system and then moves a message that the user has filed in a folder on the mobile device 24 to the corresponding folder on the host system 10. Correspondingly, when the user has filed a message in a folder on the host system 10, the folder structure synchronization process 136 will move the message to the corresponding folder on the mobile device 24. This is advantageous, for example, for a user who uses his message store as a measure of incomplete and complete jobs.

[0079] FIGS. 8 through 18 illustrate in more detail the steps required to synchronize the messages and folders of the mobile device 24 to the host system 10. FIG. 8 sets forth the method steps carried out by the host system 10 to assign folder IDs to the folders (step 142 from FIG. 7). When the mobile device 24 is plugged into 160 the host system 10, the last assigned folder ID is retrieved from the host system 10 at step 162. A “special” folder list is retrieved in step 164 from the store of the host system 10. A “special” folder is a folder such as a delete folder or an inbox folder where specific rules are set for managing messages within the folder. Based on the hierarchical structure, the host system 10 gets the top folder in step 166 and checks if the top folder is flagged in step 168. If the top folder is not flagged, step 170 assigns a folder ID to the folder based on the last assigned number retrieved in step 162. Once the top folder is assigned an ID number, the top folder is checked against the special folders and assigned a folder type in step 172.

[0080] By continuing to select through the hierarchical folder structure, step 174 retrieves subfolders of the top folder. The subfolder is checked for a folder ID in step 176 and assigned a folder ID in step 178 if no folder ID is found in step 176. Step 180 assigns a folder type to the subfolder. Step 182 checks for a subfolder underneath the current folder. If another subfolder is found, it is assigned as the top folder in step 184 and returned to step 174. If there are no more subfolders underneath the current subfolder, step 186 retrieves the next subfolder and returns the retrieved subfolder to step 176. Once the last subfolder is retrieved, step 190 ends the tag and retrieve step 142 of the folder structure synchronization process 136.

[0081] FIG. 9 sets forth the steps of retrieving the messages from the host system 10 as shown in step 146 of FIG. 7. Step 200 retrieves the list of unique messages from the store. The first unique message is checked for a folder ID in step 202. If a folder ID is not assigned, the current folder ID is assigned to the message in step 204. Step 206 checks the folder ID of the message against the current folder ID to see if they match. If the current ID and the message ID do not match, a move flag is set in step 208. The current folder ID is indicated in step 210, the next message is retrieved in step 212, and the next message is returned to step 202. Once all unique messages have been retrieved in step 212, the process ends in step 214. The list of unique messages is referred to as messages ‘A’.

[0082] The steps set forth in FIG. 9 are repeated for the mobile device 24. The messages from the mobile device 24 are referred to as messages ‘B’. Once these steps have been accomplished, the folder structure synchronization process 136 includes a list of all unique messages ‘B’ and ‘A’ in the mobile device 24 and the host system 10, respectively. For each message in the lists, a move flag is either on or off. The move flags of equivalent messages in the set of messages ‘A’ and ‘B’ are compared in FIG. 10 to determine the proper folder placement of the message.

[0083] FIGS. 10A and B set forth the steps of synchronizing the messages between the host system 10 and the mobile device 24. Step 220 of FIG. 10 checks to see if there is a match between the IDs of the current message ‘A’ and the first message ‘B’. If the IDs do not match, step 222 updates message ‘B’ to the next message in the list of ‘B’ messages. Once a matching message is found, step 224 checks if the move flag for message ‘A’ is on and the move flag for message ‘B’ is off. If this is the case, message ‘B’ is moved to the folder having the folder ID of message ‘A’ on the mobile device 24 in step 226. If the move flag status is not equal to the check in step 224, step 230 checks for a different flag status.

[0084] Step 230 checks if the move flag for message ‘B’ is on and the move flag for message ‘A’ is off. If this is the case, message ‘A’ is moved to the folder having the folder ID of message ‘B’ on the host system in step 232. If the move flag status is not equal to the check in step 230, step 234 checks for move flags in both message ‘A’ and message ‘B’ to be on. If both flags are on, step 238 decides which message to move based on a conflict resolution structure. The conflict resolution structure is a predetermined rule where the software moves one of the messages based on the folder ID of the other message. If both flags are off, step 240 checks to see if the folder IDs of message ‘A’ and message ‘B’ are different. If the folder IDs are different, the conflict resolution structure of step 238 decides which message to move. If the folder IDs are the same, messages ‘A’ and ‘B’ remain in their current folders as shown in step 242.

[0085] Step 246 checks if message ‘B’ was moved. If message ‘B’ was not moved, the message ‘B’ move flag is reset in step 250. Message ‘A’ is checked in step 252 to see if it moved. If message ‘A’ did not move, the move flag for message ‘A’ is reset 254. The procedure for checking the move status of the messages is completed in step 256.

[0086] FIG. 11 sets forth the method steps of assigning an ID to a newly received message. When a new message is received in step 260, the message is tagged with a unique ID in step 262. Once the message has a unique ID, step 264 checks if the folder in which the message is to be stored has a folder ID. If the folder has an ID, the folder ID of the message structure 120 for the new message is set to the folder ID value in step 266. If the folder does not have an ID, the folder ID of the message structure 120 for the new message is set to zero as shown in step 268. After the folder ID has been set in step 266 or 268, the message is sent to the device by the redirector in step 270.

[0087] The user has the option to move a message between folders on either the mobile device 24 or the host system 10. For example, a user who has a “to do” folder on both the host system 10 and the mobile device 24, might receive a message on the mobile device 24 when he is away from his host system 10. The redirector program might be instructed to place incoming messages into an Inbox folder on the device. After reviewing the message, the user decides to file the message into the “to do” folder on the mobile device 24. The software system for organizing messages and folders sends a move signal to the host system 10 to move the same message to the “to do” folder on the host system. Later, the user decides to move the message again to a “completed tasks” folder which also resides on both the mobile device 24 and the host system 10, but this time the user initiates the move at the host system 10. The software system for managing folders and messages sends a move signal to the mobile device 24 to initiate the same move on the host system 10. This method and system of moving messages between folders on the host system 10 and the mobile device 24 employs the “push” paradigm of the redirector software. The method steps for moving the message between folders are shown in FIG. 12 and the method steps of FIGS. 13-17 show the steps taken at the host system 10 and the mobile device 24 when the user has initiated a move on one of the devices.

[0088] A message is selected in step 280. A folder to place the message is selected in step 282. The selected message is moved to the selected folder in step 284. The folder ID of the selected folder is assigned to the folder ID of the message structure 120 for the selected message in step 286 and the move flag status is set to on in step 288. Finally, the message has been properly moved and the steps end at step 290.

[0089] Once the message has been moved on either the mobile device 24 or the host system 10, the redirector preferably attempts to move the identical message to the corresponding folder on the other device. Shown in FIG. 13 are the preferred steps in sending a move signal from the mobile device 24 to the host system 10. After the message has been moved in step 292 of FIG. 13, step 294 sends a message to move the message x to the folder y and waits for a confirmation signal in step 296. Step 298 checks if the message was successfully moved by the redirector. If the message was moved, the folder ID of message x is updated in step 300. If the message was not moved, then the redirector stops in step 302, and the message will be moved during synchronization.

[0090] Moving a message on the mobile device 24 requires a move command to be sent to the host system 10 as described above. But, moving a message on the host system requires both checking to see if the message was sent to the mobile device 24 and if the folder the message was moved to exists on the mobile device 24. These steps are set forth in FIG. 14. Once the redirector has received a move message command from the host system 24 that a message has been moved in step 304, the redirector checks to see if the message has been sent to the device in step 306. If the message was not sent to the mobile device 24, the redirector does not attempt to send the move command and stops at step 308. If the message was delivered to the mobile device 24, then step 310 determines if the folder that the message was moved to has a folder ID. The folder may not have an ID if, for example, the user created the folder at some point after the last synchronization. If the folder does not have a folder ID, the redirector does not forward the move message command and the redirector stops at step 314. The move will be made when the mobile device 24 and the host system 10 are synchronized and the folder with the correct folder structure 130 is generated.

[0091] If the folder ID does exist for the folder, then the move message command is sent in step 316. The redirector awaits acknowledgement of the move in step 318. If the acknowledgement is not received, the redirector stops at step 320. If acknowledgement of the move is received, step 322 tags the message with the current folder ID.

[0092] FIG. 15 shows the steps performed at the mobile device 24 when a move message command is received from the host system 10. Similarly, FIG. 16 shows the steps performed at the host system 10 when a move command is received from the mobile device 24. Both functions require (1) receiving a move command, (2) checking to see if the command may be executed, and (3) reacting with a negative confirmation or moving the message and positively confirming.

[0093] Step 330 of FIG. 15 occurs when the mobile device 24 receives a move command. Step 332 checks if the folder exists on the mobile device 24. If the folder does not exist, a negative confirmation is sent to the host system 10 in step 334. Otherwise, the mobile device 24 is tagged 336 with the new folder ID, the message's folder ID is updated in step 338, and a positive confirmation is sent to the host system 10 in step 340.

[0094] FIG. 16 shows the steps of acting upon a move message command at the host system 10. The move command is received 350. Step 352 locates the message in the store. Step 354 determines if the folder is located in the store. If the folder is not located in the store, a negative confirmation is sent to the mobile device 24 in step 356. If the folder is located in the store, the message is moved 360 to the folder. Step 362 determines if the move was successful. A successful move updates the message's folder ID in step 364 while an unsuccessful move sends a negative confirmation 370 to the mobile device 24.

[0095] Special folders can require a special set of instructions to deal with message management. For example, a deleted folder can be created to detect deletions at either the mobile device 24 or the host system 24. When the message is deleted, the redirector must check to see if the user has previously chosen to delete messages off of both the mobile device 24 and the host system 10 when it is deleted on one of these two.

[0096] The steps set forth in FIG. 17 show how the redirector accordingly handles a delete request. The delete process is started 380 when the user has selected a message for deleting. The message is selected 382 and then deleted 384 by the software on either the mobile device 24 or the host system 10. The software then determines 386 if the delete feature is set to delete messages on both the mobile device 24 and the host system 10. If the delete feature is not set for both devices, the software simply deletes the message locally 390. If the delete feature is set to both devices, the folder ID of the deleted folder is assigned to the message in step 392. The move flag for the message is set on 394 so that the deletion can be detected on the other device. The delete process is completed 396.

[0097] Finally, the folder management system controls wasted use of resources by purging the earliest messages once allocated space is exceeded, as shown in FIG. 18. The purge process is started in step 400. The software determines 402 if storage requirements exceed the storage space allocated for messages. If the storage requirements are not exceeded, the purge process is ended 404. If the storage space is exceeded the earliest message is deleted, but the message structure 120 is retained in step 406.

[0098] FIGS. 19 and 20 set forth a method of using folder lists as a trigger source for the redirector program 12. In FIG. 19, the user selects 408 a folder and the folder is stored 410 in the folder list. FIG. 20 shows the steps set forth for forwarding a message based on the folder list. The message could, for instance be a new piece of mail. The folder list is loaded 412. A new mail notification is received 414. The software checks if the mail is in a folder from the folder list in step 416. If the mail is not in a folder listed in the folder list, the process stops 418. If the mail is in a folder listed in the folder list, then the redirector forwards the message to the mobile device 24 in step 420, as described above.

[0099] Having described in detail the preferred embodiments of the present invention, including the preferred methods of operation, it is to be understood that this operation could be carried out with different elements and steps. This preferred embodiment is presented only by way of example and is not meant to limit the scope of the present invention which is defined by the following claims.

Claims

1. A system for two-way synchronization between electronic mailboxes stored at a host system and a mobile communication device, each of the electronic mailboxes being organized into a set of hierarchical folders for storing received messages, the system comprising: means for receiving messages at the host system and storing the received messages in the set of hierarchical folders of the host system's electronic mailbox; means for determining whether to redirect the received messages from the host system to the mobile communication device and for each message that meets the determining step, for assigning a unique message ID to the message and redirecting the message with its unique message ID to the mobile communication device; means for receiving the redirected messages at the mobile communication device and storing them in the set of hierarchical folders at the mobile communication device; means for coupling the mobile communication device to the host system; means for synchronizing the set of hierarchical folders at the host system with the set of hierarchical folders at the mobile communication device; means for retrieving a first list of messages from the host system, wherein the first list of messages are those messages that met the determining step and were redirected to the mobile communication device; means for retrieving a second list of messages from the mobile communication device; means for comparing the first list of messages to the second list of messages to identify messages having the same unique message ID and for determining whether the messages having the same unique message ID are stored in the same folders within the respective sets of hierarchical folders at the host system and the mobile communication device where the messages are stored; and means for determining whether the messages having the same unique message IDs are stored in different folders within the respective sets of hierarchical folders and for determining which message should be moved and for moving that message so that the messages having the same unique message IDs are stored in the same folders within the respective sets of hierarchical folders at the host system and the mobile communication device.

2. The system of claim 1, further comprising: means for de-coupling the mobile communication device and the host system; means for moving one of the messages at the mobile communication device so that it is stored in a different folder than the message having the same unique message ID at the host system; means for transmitting a move command message from the mobile communication device to the host system to indicate that the message has been moved, the move command message including the unique message ID of the moved message and an identification of the folder in which the message is presently stored at the mobile communication device; and means for moving the message corresponding to the unique message ID contained in the move command message at the host system so that it is stored in the same folder as the folder identified in the move command message.

3. The system of claim 1, further comprising: means for de-coupling the mobile communication device and the host system; means for moving one of the messages at the host system that was redirected to the mobile communication device so that it is stored in a different folder than the message having the same unique message ID at the mobile communication device; means for transmitting a move command message from the host system to the mobile communication device to indicate that the message has been moved, the move command message including the unique message ID of the moved message and an identification of the folder in which the message is presently stored at the host system; and means for moving the message corresponding to the unique message ID contained in the move command message at the mobile communication device so that it is stored in the same folder as the folder identified in the move command message.

4. The system of claim 1, wherein the host system and the mobile communication device are coupled via a wired connection.

5. The system of claim 1, wherein the host system and the mobile communication device are coupled via a wireless connection.

6. The system of claim 1, wherein the means for synchronizing the set of hierarchical folders further comprises: means for associating a unique folder ID with each folder in the sets of hierarchical folders at the host system and the mobile communication device; means for generating a folder list including the folder IDs of the set of hierarchical folders at the host system; means for providing the folder list to the mobile communication device; and means for updating the set of hierarchical folders at the mobile communication device using the folder list so that the set matches the set of hierarchical folders at the host system.

7. The system of claim 1, further comprising: means for associating a move flag with each of the messages having unique message IDs at both the host system and the mobile communication device; and means for setting the move flag for each message that is moved from one folder to another folder at either the host system or the mobile communication device.

8. The system of claim 7, wherein the means for comparing further comprises means for examining the move flags for each of the messages having the same unique message IDs to determine if one of the messages have been moved from one folder to another folder at either the host system of the mobile communication device.

9. The system of claim 1, further comprising: means for associating a folder ID with each message stored in the host system and the mobile communication device, wherein the folder IDs identify the folder location of each message within the respective sets of hierarchical folders; and wherein the means for comparing further comprises means for comparing the folder IDs of the messages that have the same unique message ID to determine whether the messages are stored in the same folders within the respective sets of hierarchical folders at the host system and the mobile communication device.

10. The system of claim 2, wherein the move message command is transmitted from the mobile communication device to the host system over a wireless connection, further comprising: means for enabling the transmission of the move message commands at the mobile communication device, wherein a user of the mobile communication device can either enable or disable the transmission of the move message commands.

11. The system of claim 1, further comprising: means for de-coupling the mobile communication device and the host system; means for moving a plurality of the messages at the mobile communication device so that the plurality of messages are stored in a different folders than the messages having the same unique message IDs at the host system; means for generating a move command message for each of the plurality of messages that were moved, each move command message indicating that the message has been moved, the move command message including the unique message ID of the moved message and an identification of the folder in which the message is presently stored at the mobile communication device; means for bundling the move message commands into a bundled transmission and transmitting the bundled transmission to the host system; and means for moving the messages corresponding to the unique message IDs contained in the bundled move command messages at the host system so that the messages are stored in the same folders as the folders identified in the bundled move command messages.

12. The system of claim 1, further comprising: means for providing a message structure for storing the messages, the message structure including a header portion and a message portion, the header portion including fields for storing the unique message ID assigned to the message and also for storing an identification of the folder in which the message is stored.

13. The system of claim 1, further comprising: means for providing a folder structure for each of the folders in the set of hierarchical folders at the host system and the mobile communication device, the folder structure including a folder identification field and a folder type field.

14. The system of claim 13, further comprising: means for designating at least one of the folders in the set of hierarchical folders as a deleted message folder using the folder type field of the folder so designated; and means for periodically deleting all of the messages stored in the folder at the host system.

15. The system of claim 1, wherein the means for determining whether to redirect the received messages further comprises: means for designating certain folders in the set of hierarchical folders at the host system for redirection; and means for determining whether the received messages are stored in the designated folders, and if so, for assigning the unique message ID to those messages and redirecting them with the unique message IDs to the mobile communication device.

16. A method of synchronizing messages stored in electronic mailboxes at a host system and at a mobile communication device, each of the electronic mailboxes being organized into a set of hierarchical folders where the messages are stored, comprising the steps of: redirecting messages received at the host system to the mobile communication device, each redirected message including a unique message ID; storing the redirected messages in the set of hierarchical folders at the mobile communication device; synchronizing the set of hierarchical folders at the host system with the set of hierarchical folders at the mobile communication device; retrieving a first list of messages that were redirected from the host system to the mobile communication device and a second list of messages stored at the mobile communication device; comparing the first list of messages to the second list of messages to identify messages having the same unique message ID and to determine whether the messages having the same unique message ID are stored in the same folders within the hierarchical folders at the host system and the mobile communication device; and if the messages having the same unique message IDs are stored in different folders within the hierarchical folders then moving one of the messages so that the messages are stored in the same folders at the host system and the mobile communication device.

17. The method of claim 16, further comprising the steps of: moving one of the messages at the mobile communication device so that it is stored in a different folder than the message having the same unique message ID at the host system; transmitting a command message to the host system indicating that the message has been moved, the command message including the unique message ID of the moved message and an identification of the folder in which the message is presently stored at the mobile communication device; and moving the message corresponding to the unique message ID contained in the command message at the host system so that it is stored in the same folder as the folder identified in the command message.

18. The method of claim 16, further comprising the steps of: moving one of the messages at the host system that was redirected to the mobile communication device so that it is stored in a different folder than the message having the same unique message ID at the mobile communication device; transmitting a command message to the mobile communication device to indicate that the message has been moved, the command message including the unique message ID of the moved message and an identification of the folder in which the message is presently stored at the host system; and moving the message corresponding to the unique message ID contained in the command message at the mobile communication device so that it is stored in the same folder as the folder identified in the command message.

19. The method of claim 16, further comprising the step of: coupling the host system and the mobile communication device via a wired connection.

20. The method of claim 16, further comprising the step of: coupling the host system and the mobile communication device via a wireless connection.

21. The method of claim 16, wherein the synchronizing the set of hierarchical folders step further comprises the steps of: associating a folder ID with each folder in the sets of hierarchical folders at the host system and the mobile communication device; generating a folder list including the folder IDs of the set of hierarchical folders at the host system; providing the folder list to the mobile communication device; and updating the set of hierarchical folders at the mobile communication device using the folder list.

22. The method of claim 16, further comprising the steps of: associating a move flag with each of the messages having unique message IDs at both the host system and the mobile communication device; and setting the move flag for each message that is moved from one folder to another folder at either the host system or the mobile communication device.

23. The method of claim 22, wherein the comparing step further comprises the step of examining the move flags for each of the messages having the same unique message IDs to determine if one of the messages have been moved from one folder to another folder at either the host system of the mobile communication device.

24. The method of claim 16, further comprising the steps of: associating a folder ID with each message stored in the host system and the mobile communication device that identifies the folder location of each message; and comparing the folder IDs of the messages that have the same unique message ID to determine whether the messages are stored in the same folders at the host system and the mobile communication device.

25. The method of claim 17, wherein the command message is transmitted from the mobile communication device to the host system over a wireless connection, further comprising the steps of: enabling the transmission of the command message at the mobile communication device, wherein a user of the mobile communication device can either enable or disable the transmission of the command message.

26. The method of claim 16, further comprising the steps of: moving a plurality of the messages at the mobile communication device so that the plurality of messages are stored in a different folders than the messages having the same unique message IDs at the host system; generating a command message for each of the plurality of messages that were moved, each command message indicating that the message has been moved, the command message including the unique message ID of the moved message and an identification of the folder in which the message is presently stored at the mobile communication device; bundling the command messages into a bundled transmission and transmitting the bundled transmission to the host system; and moving the messages corresponding to the unique message IDs contained in the bundled command messages at the host system so that the messages are stored in the same folders as the folders identified in the bundled command messages.

27. The method of claim 16, further comprising the steps of: providing a data structure for storing the messages, the data structure including a header portion and a message portion, the header portion including fields for storing the unique message ID assigned to the message and also for storing an identification of the folder in which the message is stored.

28. The method of claim 16, further comprising the steps of: providing a data structure for each of the folders in the set of hierarchical folders at the host system and the mobile communication device, the data structure including a folder identification field and a folder type field.

29. The method of claim 28, further comprising the steps of: designating at least one of the folders in the set of hierarchical folders as a deleted message folder using the folder type field; and if the folder type field indicates that the folder is a deleted message folder, then periodically deleting all of the messages stored in that folder at the host system.

30. The method of claim 16, further comprising the steps of: determining whether to redirect the received messages at the host system to the mobile communication device by: designating certain folders in the set of hierarchical folders at the host system for redirection; and determining whether the received messages are stored in the designated folders, and if so, then assigning the unique message ID to those messages and redirecting them with the unique message IDs to the mobile communication device.

31. A message synchronization method, comprising the steps of: redirecting messages received at a host system to a mobile communication device, each redirected message including a unique message ID; storing the redirected messages in a set of hierarchical folders at the mobile communication device; synchronizing a set of hierarchical folders at the host system with the set of hierarchical folders at the mobile communication device; comparing data regarding the messages stored at the host system with the messages stored at the mobile communication device to identify messages having the same unique message ID and to determine whether those messages are stored in the same folders within the hierarchical folders at the host system and the mobile communication device; and if the messages having the same unique message IDs are stored in different folders within the hierarchical folders then moving one of the messages so that the messages are stored in the same folders at the host system and the mobile communication device.

32. The method of claim 31, further comprising the steps of: moving one of the messages at the mobile communication device; providing information to the host system indicating that the message has been moved; and moving the message at the host system so that it is stored in the same folder as the message at the mobile communication device.

33. The method of claim 31, further comprising the steps of: moving one of the messages at the host system; providing information to the mobile communication device to indicate that the message has been moved; and moving the message at the mobile communication device so that it is stored in the same folder as the message at the host system.

34. The method of claim 31, further comprising the step of: coupling the host system and the mobile communication device.

35. The method of claim 34, further comprising the step of: coupling the host system and the mobile communication device via a wired or wireless connection.

36. The method of claim 31, wherein the synchronizing the set of hierarchical folders step further comprises the steps of: associating an identifier with each folder in the sets of hierarchical folders at the host system and the mobile communication device; generating data including the identifiers of the set of hierarchical folders at the host system; providing the data to the mobile communication device; and updating the set of hierarchical folders at the mobile communication device using the data.

37. The method of claim 31, further comprising the steps of: associating a move indicator with each of the messages having unique message IDs at both the host system and the mobile communication device; and setting the move indicator for each message that is moved from one folder to another folder at either the host system or the mobile communication device.

38. The method of claim 37, wherein the comparing step further comprises the step of examining the move indicators for each of the messages having the same unique message IDs to determine if one of the messages have been moved from one folder to another folder at either the host system of the mobile communication device.

39. The method of claim 31, further comprising the steps of: associating a folder ID with each message stored in the host system and the mobile communication device that identifies the folder location of each message; and analyzing the folder IDs to determine whether the messages are stored in the same folders at the host system and the mobile communication device.

40. The method of claim 32, wherein the information is transmitted from the mobile communication device to the host system over a wireless connection, further comprising the steps of: enabling the transmission of the information at the mobile communication device, wherein a user of the mobile communication device can either enable or disable the transmission of the information.