`Volkswagen Group of America, Inc. - Petitioner
`
`1
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`US 6,401,112 B1
`Page 2
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`U.S. PATENT DOCUMENTS
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`5,961,590 A * 10/1999 Mendez et al.
`5,966,714 A * 10/1999 Huang et al.
`6,018,762 A *
`1/2000 Brunson et al.
`
`.
`
`709/206
`
`707/201
`.......... .. 709/206
`
`OTHER PUBLICATIONS
`
`.
`.
`.
`e
`e
`e
`1111€111L1111< 13106111116 (1990)
`Madnlck, S. et a1., “Loglcal Connectlvltyt Apphcatlons,
`Requirements, Architecture, and Research Agenda,” MIT,
`System Sciences, 1991, Hawaii Int’l, vol. 1, IEEE, Jun.
`1991.
`
`Dayten, D.’ «FRX extends repemng pewer of Platinum
`Series: (IBM Desktop Software’s line of accounting soft-
`),, PCW k V8 N 5
`29(2) F b 1991
`>1"
`Ware’
`f9 >
`"
`>
`9'
`gee
`5;
`Cobb, et a1., Paradox
`Handbook 3 Edltlon, Bantafn
`(1991), pp, 803-816,
`Alfieri, “The Best Book of: WordPerfect Version 5.0,”
`Hayden Books (1998), pp. 153-165 and 429-435.
`User Manual for PC—Link for the B.O.S.S.and the PC—Link
`for the B.O.S.S. Traveling Software Inc. (1989).
`User Manual for Connectivity Pack for the HP 95LX,
`H9W19“PaC1‘ard C9mPaPY (1991)
`.
`01ga111Z€1 L1111<H 0P€1at1011 Manual, Sha1P E1€C110111CS C01-
`poratlon, No Date.
`“Open Network Computing-Technical Overview,” Sun
`Technical Report, Sun Microsystems, Inc., pp. 1-32 (1990).
`Exeerpt from Miereeefi Windows 95 Deeumematien’ (3)
`pages
`'
`.
`.
`Excerpt from LapL1nk World Wide Web for SpeedSync, (1)
`Page 101a1
`Newton: Message Pad Handbook, Apple Computer, Inc.,
`Chapter 4 “Reference” and “Appendix B—NewtonMail
`Setup and Access Numbers”,
`and
`
`* cited by examiner
`
`1/1995 Clough 61 a1 ~~~~~~~~~~~~ ~~ 345/173
`2/1995 Crozier ........... ..
`345/762
`
`.......... .. 709/223
`7/1995 Shaheen et al.
`10/1995 Thompson et al.
`....... .. 707/101
`12/1995 Dauerer et al.
`........... .. 707/201
`5/1996 Frid—Nielsen etal. ........ .. 705/9
`7/1996 King et al.
`............... .. 707/200
`8/1996 Robinson et al,
`707/205
`8/1996 Poling ............ ..
`707/201
`
`
`
`. . . .
`
`. . . .. 702/2
`10/1996 Clark, Jr. et al.
`' 370/402
`11/1996 Shuen """"" "
`710/300
`11/1996 Yeh .......... ..
`......... .. 707/206
`1/1997 Robinson etal.
`slaughter,
`et al.
`5/1997 Rybicki et al.
`........... .. 345/839
`7/1997 Brunson ...... ..
`709/206
`7/1997 Scott et al.
`.
`707/201
`9/1997 Chen 91 31-
`-
`370/420
`9/1997 Clark 9191'
`‘
`" 707/201
`9/1997 Crozier ..................... .. 707/540
`11/1997 Boothby ................... .. 707/203
`12/1997 Skinner et al.
`702/186
`12/1997 Crozier ........... ..
`345/762
`1/1998 Man—Hak Tso
`707/201
`1/1998 Alley etal,
`707/201
`3/1998 K11<1111S
`709/246
`3/1998 Kueala ...................... .. 707/10
`3/1998 Smith et al.
`................ .. 701/29
`4/1998 Perlman et al.
`707/201
`5/1998 Huang et al.
`707/201
`6/1998 Kar et al.
`709/248
`12/1998 Alley et al.
`................. .. 707/10
`1/1999 Wright, Jr. et al.
`.... .. 707/104.1
`1/1999 Moen et al.
`........... .. 379/114.2
`2/1999 Ballantyne et al.
`.......... .. 705/2
`9/1999 Hoss et al.
`............... .. 709/206
`
`5,379,057 A
`5,392,390 A
`5,434,994 A
`5,463,772 A
`5,475,833 A
`5,519,606 A
`5,537,592 A
`5,544,356 A
`5,546,539 A
`
`5,566,069 A
`5572528 A
`5,574,859 A
`5,592,669 A
`A
`5,630,081 A
`5,647,002 A *
`5,649,195 A
`5666362 A
`5566530 A *
`5,666,553 A
`5,684,990 A
`5,696,702 A
`5,701,423 A
`5,706,509 A
`5,710,922 A
`5,727,159 A
`5,727,202 A *
`5,729,452 A
`5,742,820 A
`5,758,354 A *
`5,761,439 A
`5,845,282 A
`5,857,201 A
`5,864,604 A
`5,867,821 A
`5,951,638 A *
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`2
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`Jun. 4, 2002
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`Sheet 1 of 5
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`U.S. Patent
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`Jun. 4, 2002
`
`Sheet 3 of 5
`
`US 6,401,112 B1
`
` MS Exchange
`
`Server
`
`280
`
`
`
`‘ Network Software
`
`}—/ 255
`
`
`
`E/IAPI
`I Operating System i
`250
`
`
`
`
`To
`FIG. 2B
`
`(3)
`
`210
`
`Client
`
`HotSync
`Program
`
`2“
`
`_
`
`-
`
`
`
`231
`
`Hot Sync
`Manager
`
`251
`
`233
`
`
`FIG. 2A
`
`5
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`U.S. Patent
`
`Jun. 4, 2002
`
`Sheet 4 of 5
`
`US 6,401,112 B1
`
`280
`
`270
`
`21 0
`
`Client
`
`‘ Network Software
`
`H Operating System
`
`\
`
`Hot Sync
`Manager
`
`211
`
`313
`
`Database '
`
`HotSync
`Program
`
`FIG. 2B
`
`250
`
`257
`
`
`
`242
`
`
`
`CC:MaI|
`
`Client
`
`FIG. 2B
`
`
`
`
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`6
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`U.S. Patent
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`Jun. 4, 2002
`
`Sheet 5 of 5
`
`US 6,401,112 B1
`
`
` Retrieve New Outgoing Email from Portable and
`
`Send That New Outgoing Email
`
`310
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`J Compare Portab|e's Email
`From at Last Synchronization
`to Determine New, Changed,
`& Deleted Email on the
`Portable System.
`\
`/
`77 ‘
`///
`\
`.
`ve;¢___._
`
`
`Compare Email from Server to Email from Portable
`to Determine New, Changed, & Deleted Email on the Server.
`
`340
`
`_
`
`
`Delete Email that has been Deleted on Either System.
`Mark "read" Email that has been Read on Either System.
`File Away Email that has been Filed on Either System.
`
`
`
`
`350
`
`FIG. (3
`
`7
`
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`
`US 6,401,112 B1
`
`1
`METHOD AND APPARATUS FOR
`SYNCHRONIZING AN EMAIL CLIENT ON A
`PORTABLE COMPUTER SYSTEM WITH AN
`EMAIL CLIENT ON A DESKTOP
`COMPUTER
`
`FIELD OF THE INVENTION
`
`invention relates to the field of portable
`The present
`computers systems. Specifically, the present invention dis-
`closes a systems for synchronizing an email client on a
`portable computer system with an email client on a desktop
`computer system.
`
`BACKGROUND OF THE INVENTION
`
`Personal computer systems have become common tools in
`modern society. One of the most important uses for personal
`computers is electronic mail (email). Personal computer
`users use email to send notes and computer files to other
`computer users.
`Many personal computer users also use small portable
`palmtop computer systems such that the personal computer
`user can carry important personal information. To store the
`important personal information, palmtop computer systems
`usually provide Personal Information Management (PIM)
`applications such as an address book, a daily organizer, and
`a To-Do list applications.
`In addition to the Personal Information Management
`(PIM) applications, it would be desirable to have an email
`application on the palmtop computer system. The email
`application would allow the user to send and receive email
`messages using the palmtop computer system.
`Although an email application on palmtop computer
`system would be very useful, such an application can create
`problems. For example, would incoming email arrive on the
`desktop personal computer system, the portable computer
`system or both? Furthermore, if the user deleted an email
`message on one of the two computer systems, should that
`email message appear on the other computer system? Thus,
`it would be desirable to have an email application for a
`palmtop computer system that is completely in synchroni-
`zation with an email application on a desktop personal
`computer system.
`
`SUMMARY AND OBJECTS OF THE
`INVENTION
`
`It is therefore an object of the present invention to provide
`a palmtop computer system that is fully integrated with
`common email systems used by desktop personal comput-
`ers. To accomplish this goal, the present invention intro-
`duces an email client for the portable computer system and
`an email synchronization conduit for a desktop personal
`computer system.
`The email client for the portable computer system allows
`the user to view incoming email messages. The email client
`on the portable computer system also allows the user to
`compose outgoing email messages.
`The email synchronization conduit on the desktop per-
`sonal computer system is responsible for synchronizing the
`state of the portable computer email client with an email
`client on a personal computer system. After a synchroniza-
`tion event, the email synchronization conduit ensures that
`the email state on the portable computer system exactly
`matches the email state on the desktop personal computer
`system. For example, if an email message is deleted on email
`client of the portable computer system then a matching copy
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`of that email message will be deleted from the desktop
`personal computer system. Similarly, if an email message is
`deleted on the email client of the desktop personal computer
`system then that email message will be deleted from the
`portable computer system. By keeping the email state of the
`two different computer systems in exact synchronization, the
`user can switch between the email client on the portable
`computer system and the email client on the desktop per-
`sonal computer system without missing a message or read-
`ing a redundant message.
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`The objects, features, and advantages of the present
`invention will be apparent
`from the following detailed
`description of the preferred embodiment of the invention
`with references to the following drawings.
`FIG. la illustrates a portable computer system and a
`personal computer system equipped with a cradle for syn-
`chronizing with the portable computer system.
`FIG.
`lb illustrates a block diagram that depicts the
`software architecture for synchronizing information on the
`portable computer system with information on a desktop
`personal computer system.
`FIG. 2a illustrates a block diagram that depicts the
`software architecture for synchronizing email on the por-
`table computer system with email on the desktop personal
`computer system using the Microsoft® MAPI protocol.
`FIG. 2b illustrates a block diagram that depicts the
`software architecture for synchronizing email on the por-
`table computer system with email on the desktop personal
`computer system using the Lotus® VIM protocol.
`FIG. 3 illustrates a flow diagram that describes how email
`on the desktop personal computer system is synchronized
`with email on the portable computer system.
`DETAILED DESCRIPTION
`
`Methods and apparatus for implementing a palmtop com-
`puter system that is well integrated with a personal computer
`system is disclosed. In the following description, for pur-
`poses of explanation, specific nomenclature is set forth to
`provide a thorough understanding of the present invention.
`However, it will be apparent to one skilled in the art that
`these specific details are not required to practice the present
`invention.
`In other
`instances, well-known circuits and
`devices are shown in block diagram form to avoid obscuring
`the present invention.
`
`Basic Synchronization
`
`FIG. la illustrates a portable computer system 130 that
`communicates and synchronizes information with a personal
`computer system 110. To synchronize the information in the
`two computer systems, a user places the portable computer
`system 130 into the cradle 120 and presses synchronization
`button 125. The synchronization button 125 activates a
`synchronization program on the portable computer system
`130. The synchronization program on the portable computer
`system 130 communicates with a peer synchronization pro-
`gram on the personal computer system ll0. The two syn-
`chronization programs synchronize the information on the
`two computer systems.
`FIG. lb illustrates a block diagram of the software com-
`ponents that perform the synchronization of the two com-
`puter systems. In FIG. lb, the portable computer 160 has
`two different programs, program A and program B, that
`execute on the portable computer 160. Program A and
`program B use a common database 163 to store their data.
`
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`US 6,401,112 B1
`
`3
`Referring to FIG. lb, a synchronization cradle 180 is
`illustrated below the portable computer 160. The synchro-
`nization cradle 180 has a button 185 that activates a syn-
`chronization Program (HotSync) 161 in the portable com-
`puter system l60. When activated, the HotSync Program
`161 communicates with the peer synchronization program
`(HotSync Manager) 170 in the personal computer 150. The
`HotSync Manager 170 operates by executing a series of
`conduit programs such as conduit program A and conduit
`program B illustrated in FIG. lb. Each conduit program is
`used to synchronize the information associated with a par-
`ticular program on the portable computer system. Conduit
`programs can also perform additional tasks such as software
`installation. A full description of the synchronization archi-
`tecture can be found in U.S. Pat. No. 5,727,202 entitled
`“Method and Apparatus for Synchronizing Multiple Files
`On Two Different Computer Systems”.
`In FIG. lb, conduit program A and conduit program B are
`used to synchronize the data for application program A and
`application program B on the portable computer 160 respec-
`tively. The HotSync Manager 170 communicates with the
`HotSync Program 161 in order to access the database 163 on
`the portable computer 160. The necessary records from of
`the database 163 are copied to the personal computer such
`that the conduit programs on the personal computer can
`process the records. In the example of FIG. lb, the records
`from database 163 that are associated with application
`program A and application program B are copied into the
`personal computer and then reconciled with databases A and
`database B by conduit A and conduit B respectively. After
`the records have been synchronized,
`the synchronized
`records are written back to the database 163 on the portable
`computer system 160.
`
`Email Synchronization
`
`information is not as simple as
`Synchronizing email
`synchronizing a simple database such as an address list. To
`fully describe how the present invention synchronizes an
`email client program on a desktop personal computer system
`with an email client program on a portable computer system,
`a detailed description is provided with reference to FIGS.
`2a, 2b, and 3.
`FIG. 2a illustrates the general software architecture for
`synchronizing an email client program on a desktop personal
`computer system with an email client program on a portable
`computer system. In the example of FIG. 2a, the email client
`program on the personal computer uses the Microsoft MAPI
`protocol. However, other email protocols may also be used
`as will be described later.
`
`FIG. 2a illustrates a portable computer system 210 having
`an email client program 211. The email client program 211
`works with email records stored in the database 215. The
`
`email client program 211 allows the user to view received
`email stored in the database 215. The email client program
`211 also allows the user to compose new email messages to
`be sent to other computer users.
`The portable computer system requires a connection to a
`computer network infrastructure to receive new email and to
`send newly composed email messages. To connect with the
`computer network infrastructure, this document describes a
`synchronization environment wherein the portable computer
`is coupled to a personal computer using a serial link as
`depicted in FIGS. la, lb, and 2a. However, many other
`methods of connecting the portable computer system to a
`personal computer system as described in the patent appli-
`cation “Method And Apparatus Por Synchronizing A Por-
`
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`table Computer System With ADesktop Computer System”
`filed on Jan. 30, 1997 with Ser. No. 08/792,166, now U.S.
`Pat. No. 6,006,274.
`To update the email records stored in database 215, the
`user can place the portable computer system 210 into a
`cradle coupled to a personal computer through a serial link.
`The user presses a syncrhonization button on the cradle to
`activate a HotSync Program 217 on the portable computer
`system 210. The HotSync Program 217 on the portable
`computer system 210 communicates through the serial link
`with a HotSync Manager Program 231 on the personal
`computer system. The HotSync Manager Program 231
`executes a number of conduit programs to synchronize
`databases including an email conduit program 233 to syn-
`chronize the email information.
`
`To synchronize the email records from the portable com-
`puter system, the email conduit 233 communicates with a
`MAPI software layer 253 in the operating system software
`of the personal computer 250. The MAPI software layer 253
`provides a limited set of routines for manipulating email on
`an email server. Detailed information about
`the MAPI
`
`software layer can be found in the Microsoft Developer
`Network documents published by the Microsoft Corpora-
`tion.
`
`Referring to FIG. 2a, a MAPI-compliant email server 280
`is connected to a computer network 270 that is also coupled
`to the personal computer system 250. One MAPI-compliant
`email server is the Microsoft (MS) Exchanger Server illus-
`trated in FIG. 2a. To access the email information on the
`
`MAPI-compliant email server 280, an application program
`on the personal computer 250 can issue MAPI compliant
`requests to the MAPI software layer 253. The MAPI soft-
`ware layer 253 transmits a request packet across the com-
`puter network 270 to the MAPI compliant email server 280.
`In response to the properly formatted MAPI requests, the
`MAPI-compliant email server 280 sends information back to
`the MAPI software layer 253.
`For example, the Microsoft Mail email client program
`240 on the personal computer system can send and receive
`email by issuing requests to the MAPI software layer 253.
`The MAPI software layer 253 transmits the requests through
`the appropriate network software to the MAPI-compliant
`email server software 281 on a server 280. The MAPI-
`
`compliant email server software responds through the net-
`work 270 back to the MAPI layer and thus back to the mail
`client software 240.
`
`To send and received email, the email conduit 233 uses
`the same infrastructure. Thus, the email conduit 233 also
`makes requests to the MAPI software layer 253. The MAPI
`software layer 253 transmits the requests from the email
`conduit 233 through the appropriate network software to the
`MAPI-compliant email server software 281 on server 280.
`It should be noted that the email server software 281 on
`server 280 maintains the email “state” for each user that the
`
`email server services. Specifically, the email server software
`maintains a set of active email messages for each user. By
`communicating through the MAPI software layer 253, the
`email conduit 233 can synchronize the email records on the
`portable computer system 210 with the email information on
`email server software 281 on server 280.
`
`FIG. 3 illustrates a flow diagram that describes how the
`email client conduit 233 on the personal computer system
`250 synchronizes the email state on the portable computer
`system 210 and the personal computer system 250. First, at
`step 310, the email conduit 233 retrieves all the outgoing
`email from the portable computer system 210. This outgoing
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`US 6,401,112 B1
`
`5
`email is sent to the email server software 281 using MAPI
`commands such that the outgoing email is sent to the desired
`recipient. At step 315, the email conduit determines if the
`user has selected a “send-only” mode. The send-only mode
`allows the user to shorten synchronization sessions by only
`sending outgoing email. If the user has selected the send-
`only mode the email client is done and stops at step 317.
`Otherwise the email conduit continues to synchronize the
`email in database 215 with the email on the email server
`software 281.
`
`10
`
`At step 320, the email conduit 233 reads all the email for
`the user from the email server 281. If the email conduit 233
`cannot read the email from the server then the conduit will
`
`terminate since it cannot obtain the information necessary
`for the synchronization. After reading all the email from the
`email server 281 the email conduit 233 then reads all the
`
`15
`
`email stored in the database 215 in the portable computer
`system at step 330.
`At step 335, the email conduit 233 checks to see if this is
`a synchronization with the same personal computer that was
`used to perform the previous synchronization. If this is the
`same personal computer, then the email from the portable
`computer system will have valid status flags that specify the
`new, changed and deleted email from the portable computer
`system. However, if this is not the same personal computer
`that was used in the previous synchronization then the
`conduit proceeds to step 337 where it compares the email
`from the portable computer system with the email from the
`last synchronization to determine the new, changed and
`deleted email from the portable computer system. Additional
`information about the system of using a state from a previ-
`ous synchronization is available in U.S. Pat. No. 5,727,202
`entitled “Method and Apparatus for Synchronizing Multiple
`Files On Two Different Computer Systems” with Ser. No.
`08/544,927, filed on Oct. 18, 1995, now U.S. Pat. No.
`5,727,202.
`Next, at step 340, the email from the email server 281 is
`compared with the email retrieved from the portable to
`determine the new, changed and deleted email from the
`email server 281. After this step the email that is new,
`changed or deleted from the email server 281 is available.
`The final step is then to synchronize the email information
`from the email server 281 and the email information from
`
`the portable computer system. To accomplish this goal, the
`email conduit 233 uses the list of the new, changed and
`deleted email from the portable computer system and the list
`of the new, changed and deleted email from the email server
`281. Specifically, the list of the new, changed and deleted
`email from the portable computer system is used to modify
`the email on the email server 281 and the list of the new,
`changed and deleted email from the email server 281 is used
`to modify the email information on the portable computer
`system. Thus, at step 350, if an email message has been
`deleted from the email server 281 then that email message
`is deleted from the email
`list on the portable computer
`system. Similarly, if an email message has been deleted from
`the portable computer system then that computer system. If
`an email message has been modified on either system then
`that email message is modified on the other system. For
`example, if email has been marked as read on either system
`then the email is marked as read on the other system. Finally,
`if new email has been received by the email server 281, then
`that new email is copied into the database in the portable
`computer system.
`The techniques illustrated with reference to the MAPI
`based email system of FIG. 2a can be used in other email
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`systems. For example, FIG. 2b illustrates a similar mail
`arrangement. In FIG. 2b,
`the server 280 is running the
`Lotus® cc:mail server software 283 on the server 280. To
`communicate with the Lotus® cc:mail server software, a
`VIM software layer 257 is placed in the system software of
`the personal computer system 250. The VIM software layer
`257 is used by the Lotus® cc:mail client program 242. Since
`the VIM and MAPI software layers are very similar, the
`same method described in FIG. 3 can be used to synchronize
`email on systems use the VIM protocol.
`Although the present invention has been described in
`terms of specific exemplary embodiments, it will be appre-
`ciated that various modifications and alterations might be
`made by those skilled in the art without departing from the
`spirit and scope of the invention as set forth in the following
`claims.
`What is claimed is:
`
`1. A computer implemented method of synchronizing
`email between multiple computers, the method comprising:
`reading a first set of messages from a portable computer
`into a first personal computer;
`identifying an outgoing message in the first set of mes-
`sages to be delivered from the first personal computer
`to a mail server;
`identifying on the first personal computer a second set of
`messages previously retrieved from a server, the second
`set of messages having, at least once prior to a previous
`event, a first message that matched a corresponding
`message in the first set of messages;
`comparing the first set of messages with the second set of
`messages to identify if at least the corresponding mes-
`sage in the first set of messages that matched the first
`message in the second set of messages was deleted or
`modified after the previous event; and
`automatically signaling the outgoing message to the mail
`server.
`
`2. The method of claim 1, wherein the second set of
`messages include flags to identify whether each message in
`the second set of messages was added to or deleted from the
`second set of messages since a previous event.
`3. The method of claim 1, further comprising identifying
`if any messages in the second set of messages were modified
`on the first personal computer after the previous event, then
`replacing select messages in the first set of messages with
`the modified messages.
`4. The method of claim 1, further comprising causing the
`first message in the second set of messages to be deleted
`from the second set of messages if the corresponding
`message has been deleted from the first set of messages since
`the previous event.
`5. The method of claim 1, further comprising causing the
`first message in the second set of messages to be modified
`if the corresponding message has been modified on the
`portable computer since the previous event.
`6. The method of claim 1, further comprising comparing
`the first set of messages to the second set of messages to
`identify if the second set of messages includes at least a first
`new message added to the second set of messages after the
`previous event.
`7. The method of claim 6, further comprising adding the
`first new message to the first set of messages, then signaling
`the first set of messages to the portable computer.
`8. The method of claim 1, further comprising signaling the
`first set of messages to the portable computer after compar-
`ing the first set of messages and the second set of messages.
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