(12) United States Patent
`US 6,546,425 B1
`(10) Patent N0.:
`Hanson et al.
`
`(45) Date of Patent: Apr. 8, 2003
`
`U5006546425B1
`
`(54) METHOD AN I) APPARATUS FOR
`PROVIDING MOBILE AND OTHER
`INTERMITTENT CONNECTIVITY IN A
`COMPUTING ENVIRONMENT
`
`(75)
`
`Inventors: Aaron D. Hanson, Seattle, WA (US);
`Emil A. Sturniolo, Medina, OH (US);
`Anatoly Menn, Seattle, WA (US); Erik
`D. Olson, Seattle, WA (US), Joseph T.
`Savarese, Edmonds, WA (US)
`
`(73) Assignee: Netmotion Wireless, Inc., Seattle, WA
`(US)
`
`( * ) Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 0 days.
`
`(21) Appl. N0.: 09/330,310
`
`(22)
`
`Filed:
`
`Jun. 11, 1999
`
`Related US. Application Data
`Provisional application No. 60/103,598, filed on Oct. 9,
`1998.
`
`(60)
`
`Int. Cl.7 ................................................ G06F 15/16
`(51)
`[1.8. C].
`iiiiiiiiiiiiiiiiiiiiiiii 709/227; 709/228; 709/330
`(52)
`(58) Field of Search ................................. 709/245, 250,
`709/330, 229, 228, 227, 230, 203, 220,
`221, 202
`
`(56)
`
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`(57)
`ABSTRACT
`
`A seamless solution transparently addresses the character-
`istics of nomadic systems, and enables existing network
`applications to run reliably in mobile environments. The
`solution extends the enterprise network,
`letting network
`managers provide mobile users with easy access to the same
`applications as stationary users without sacrificing reliability
`or centralized management. The solution combines advan-
`tages of existing wire-line network standards with emerging
`mobile standards to create a solution that works with exist-
`ing network applications. A Mobility Management Server
`coupled to the mobile network maintains the state of each of
`any number of Mobile End Systems and handles the com—
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`connections to the network and to other peer processes. If a
`Mobile End System becomes unreachable, suspends, or
`changes network address (e.g., due to roaming from one
`network interconnect to another), the Mobility Management
`Server maintains the connection to the associated peer
`task—allowing the Mobile End System to maintain a con-
`tinuous connection even though it may temporarily lose
`contact with its network medium. In one example, Mobility
`Management Server communicates with Mobile End Sys-
`tems using Remote Procedure Call and Internet Mobility
`Protocols.
`
`(I .ist continued on next page.)
`
`76 Claims, 32 Drawing Sheets
`
`10!.
`
`101
`
`Mobile Managemznl Sysllm {WAS}
`23;
`224
`: 234]
`110'
`_H‘Conlml, User Intrrfnce
`
`Print Services
`W99
`Nahum File and
`”'0‘! 3M4» “3‘9“?"
`
`‘1!!de NT
`\
`Daiuhuse
`User/Security
`2”
`23E
`
`
`
`
`
`
`
`
`Fizsdeind Systems (ES)
`Network
`Applications
`File/Friat
`
`
`
`
`
`Mobile End Sysle'n (MES)
`Control. User Inlednce
`
`
`
`
`
`
`
`
`
`
`
`205’
`
`Appllailnns
`
`
`
` Neng'k
`
`
`Mdnss Translullnn
`
`220/ [Intermediate Dr'mr)
`
`
`
`
`
`
`
`
`TCP. UDP Transmit: II
`
`
`
`
`
`110
`
`Microsoft Corporation
`Exhibit 1016-00001
`
`Microsoft Corporation
`
`

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`Microsoft Corporation
`Exhibit 1016-00002
`
`Microsoft Corporation
`
`

`

`US 6,546,425 131
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`* cited by examiner
`
`Microsoft Corporation
`Exhibit 1016-00003
`
`Microsoft Corporation
`
`

`

`US. Patent
`
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`Exhibit 1016-00004
`
`Microsoft Corporation
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`

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`
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`

`

`US. Patent
`
`Apr. 8, 2003
`
`Sheet 3 of 32
`
`US 6,546,425 B1
`
`
`
`Call
`to TDl Via Sockets
`or directly is intercepted
`
`
`
`250
`
`
`
`Mobile Interceptor packages
`TDI cell
`in an RPC
`
`datagram and sends to
`Mobile Management Server
`
` 252
`
`
`
`
` Mobile Management Server
`
` 254
`unpackages RPC datagram
`
`
`
`FIG. 2A
`
`Mobile Management Server
`provides requested service
`
`
`
`255
`
`Applications
`
`Configuration API
`
`Socket API
`
`RPC Protocol Engine 240
`
`
`
`Internet Mobility
`(interceptor Virtual Circuit)
`Protocol
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`
`'t‘r'é'riébe'r'i' were;
`
`208
`
`206
`
`204
`
`212
`
`202
`
`200
`
`FIG. 3
`
`Microsoft Corporation
`
`Exhibit 1016-00006
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8,2003
`
`Sheet 4 of 32
`
`US 6,546,425 B1
`
`RCV TDI CALL
`
`Post RPC call
`to IMP queue
`
`Delay for
`coalesce time
`
`302
`
`304
`
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`
`
`
`Flush queue, coalesce the RFC
`calls into single fragment
`and foward to Server
`
` 308
`
`END
`
`FIG. 3A
`
`Microsoft Corporation.
`Exhibit 1016-00007
`
`Microsoft Corporation
`
`

`

`US. Patent
`
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`
`

`

`US. Patent
`
`Apr. 8,2003
`
`Sheet 6 of 32
`
`US 6,546,425 B1
`
`Control Block
`
`362
`
`Determine Association
`and Get Association
`
` 370
`364
`
`
`
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`
`Create New Association
`
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`Stop Association
`Destroy Association
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`
`
`368
`
`Schedule Association
`
`FIG. 4
`
`Microsoft Corporation.
`Exhibit 1016-00009
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8,2003
`
`Sheet 7 of 32
`
`US 6,546,425 B1
`
`
`De—Queue
`Work Request
`
`390
`
`364
`
`Receive
`
`Start
`Receiving
`
`
`
`392
`394
`
`RPC
`
`Receive
`Request
`
`
` Pending
`
`
`
`
`
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`Weight
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`
`
`
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`
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`Connect
`
`
`
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`
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`Queues
`
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`
`
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`
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`
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`Queues Marked
`
`
`
`410
`
`
`
`
`Set State To Association
`Scheduled again
`
`
`
`
`Eligible
`
`FIG. 5 Process Association Work
`
`Microsoft Corporation
`Exhibit 1016-00010
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8, 2003
`
`Sheet 8 0132
`
`US 6,546,425 B1
`
`f 3”
`
`allocate and association control block
`
`372A
`
`initialize system wide resources with defaults
`
`3728
`
`get configuration overrides
`
`initialize the coalesce timer
`
`3729
`
`insert association control block into session tob|e
`
`372H
`
`END
`
`FIG. 5A
`
`Microsoft Corporation.
`Exhibit 1016-00011
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8,2003
`
`Sheet 9 of 32
`
`US 6,546,425 B1
`
`START
`
`375\\
`
`mark the association as deleted to prevent any further
`processing of work that may be outstanding
`
`close all associated association objects including
`process, connection and address objects
`
`376A
`
`3768
`
`free all elements on work queue
`
`376C
`
`stop coalesce timer if
`
`running
`
`3750
`
`decrement association control block reference count
`
`N @ 375F
`
`
`
`destroy association specific work queue
`
`
`
`destroy object hash table
`
`
`
`\o 376E
`
`376G
`
`destroy coalesce timer
`
`remove association control block
`
`from association table
`
`free control block
`
`
`END
`
`FIG. 58
`
`Microsoft Corporation
`Exhibit 1016-00012
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8,2003
`
`Sheet 10 of 32
`
`US 6,546,425 B1
`
`CredithT
`=0
`
`mark association as "low mark pending" by setting the
`RPC_LMPQ_SEND_FLAG.
`
`379A
`
`discard all received datagrams
`
`_
`
`3798
`
`received stream events by
`throttle all
`refusing to accept
`the data
`
`37%
`
`refuse all
`
`received connect events for passive connections
`
`3790
`
`END
`
`FIG. SC
`
`Microsoft Corporation
`Exhibit 1016-00013
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8, 2003
`
`Sheet 11 of 32
`
`US 6,546,425 B1
`
`E80
`
`338
`
`638
`
`6N8
`
`ANNE\0%
`
`Emacs“.{ozvacuum0%
`
`
`
`EmEmoi£22
`
`9::
`
`EmEmoE
`obeozq
`
`ncoomm
`
`EmEmofi
`
`38m,
`
` xerox,§5m8mofiyxoza“3“”:qu
`
`30933
`
`{0;
`
`mom
`
`F0mm
`
`N0mm
`
`m0mm
`
`m.OE
`
`Microsoft Corporation
`Exhibit 1016-00014
`
`Microsoft Corporation
`
`
`
`
`
`
`

`

`US. Patent
`
`Apr. 8, 2003
`
`Sheet 12 of 32
`
`US 6,546,425 B1
`
`mam
`
`$295a£25
`
`oQBEN€252$55
`
`Essa
`
`¢mn
`
`ezmomm0%
`
`wmoaumm{0;
`
`028mg
`
`xotm>o
`
`com
`
`
`
`EEEacmmmflc5:828:30
`
`$222$8
`
`30350$30;.=8283
`
`
`
`50.303222:80
`
`
`
`28.30538500:80
`
`
`
`3053.32082
`
`“8:50
`
`>omEombm
`
`ucmmEombm
`
`5mEEmBoo
`
`ucmmEEmSoo
`
`023mm
`
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`205520
`
`33885
`
`
`
`$2223203829
`
`E30$062$05
`
`
`
`Sofie8:03:00086
`
`N.O_n_
`
`Microsoft Corporation
`Exhi
`it 1016-00015
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8,2003
`
`Sheet 13 of 32
`
`US 6,546,425 B1
`
`
`
`queue:
`PRIORITY_H|GH
`
`408
`
`/ 406
`
`Weight=queue
`Weight
`
`
`
`Fig. 8
`Process Priority
`Dispatch Queues
`
`Microsoft Corporation
`Exhibit 1016-00016
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8, 2003
`
`Sheet 14 of 32
`
`US 6,546,425 B1
`
`3.96:858.5m.6:
`
`2600%
`
`.wmm
`
`.83023:05
`326Nbrat;
`
`93.05$.05
`
`
`
`Hmmscmmncmmas:
`
`as:
`
`:N
`
`£9:
`
`biota
`
`2mmsuom
`
`eznmzom
`
`biog
`
`:9:
`
`
`
`:65E8938$283.
`
`
`
`Emfi#85385
`
`
`
`mmcoqmmmmzmumm
`
`
`
`Emfi62:8
`
`Microsoft Corporation
`Exhibit 1016-00017
`
`Microsoft Corporation
`
`
`
`
`
`
`
`

`

`US. Patent
`
`Apr. 8,2003
`
`Sheet 15 of 32
`
`US 6,546,425 B1
`
`601 602
`
`Connect
`request?
`Yes
`
`
`
`" Error“
`Out of resources
`
`
`
` cIi‘imififign
`
`resources?
`
`
`Yes
`
`
`
`Queue connect or send request and signal global event — return to calling application
`
`
`State Configure
`
`6038
`
`Dispatch connect or send request
`from IMP global request queue
`
`
`
`
`
`Any
`work pending
`
`Wait for application to
`queue work for
`connection. Go to step 625
`
`Go to step 615
`
`607
`
`
`
`
`
`
`
`
`
`
`Wait for peer address.
`Continue queuing work.
`Go to step 625
`
`Wait for security context.
`Continue queuing work.
`Go to step 625
`
`608
`
`
`
`
`Internet Mobility Protocol
`Connection Decision Tree.
`FIG. 10A Connect and Send request
`
`logic
`
`Microsoft Corporation.
`Exhibit 1016-00018
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8, 2003
`
`Sheet 16 of 32
`
`US 6,546,425 B1
`
`609
`
`610
`
`State Pending
`
`6088
`
`Send IMP Sync Frame
`
`
`
`Start
`
`611
`
`IMP retransmit
`
`timer
`
`
`
`
`_
`Has _
`_
`No
`
`
`
`Want
`Established
`Retransmlt
`
`
`
`
`timer - Go to
`frarne
`
`
`
`
`
`recewed°
`expwed?
`step 525
`
`
`
`
`
`
`
`611A
`
`Yes
`
`State Estabfished
`
`
`
`616
`
`615
`
`
`
`Hafi.
`
`
`connec Ion
`Wa‘t
`been
`Go to
`step 525 mmhenticoted
`
`
`
`Yes
`
`
`617
`
`
`Did
`authentication
`
`
`succeed?
`
`
`Yes
`
`No
`
`
`
`
`HOS
`Total
`
`
`Retransmit
`thne expked
`
`
`?
`
`YES
`
`614A
`
`Abort Connection
`Go to step #999
`
`FIG. 108
`
`Microsoft Corporation.
`Exhibit 1016-00019
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8,2003
`
`Sheet 17 of 32
`
`US 6,546,425 B1
`
`
`
`618
`
`
`ls
`
`Wait for
`
`peer .transmit
`acknowledgement.
`
`
`window
`Go to step 625
`
`
`
`620
`
`621
`
`Create tMP data frame
`
`Send IMP data frame
`
`full?
`
`
`
`
`622
`
`
`ls
`IMF?
`Start
`retransmit
`
`
`
`retransmit
`timer
`
`timer
`started?
`
`
`
`625
`
`
`
`Sleep waiting for more work.
`Return to global dispatcher
`
`FIG. 100
`
`Microsoft Corporation.
`Exhibit 1016-00020
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8,2003
`
`Sheet 18 of 32
`
`US 6,546,425 Bl
`
`626
`
`
`
`Terminate Connection
`
`
`
`
`
`627
`
`to global work queue
`Queue request
`and return to calling application
`
`
`
`IMP process global work queue
`
`Dispatched terminate request from
`
`B26A
`
`628
`
`629
`
`AbOF'E
`
`Abort Connection
`Go to step #999
`
`Graceful
`
`628A
`
`State Closing
`
`630
`
`Send IMP Mortis Frame
`
`State Mortis
`
`Start retransmit
`
`timer
`
`632
`
`
`iMP
`.
`Has
`
` Wait
`Post Mortem
`retransmit
`
`
`
`Go to
`timer
`
`frame
`
`step 637
`received?
`
`
`
`
`
`
`
`
`
`
`
`
`631
`
`632A
`
`636
`
`637
`
`State Post Mortem
`
`Release connection Resources
`
`
`
`Steep waiting for more work.
`Return to global dispatcher
`
`FIG. 11
`
`Terminate Connection request
`
`logic
`
`retransmit
`time
`expired?
`
`
`
`Yes
`
`535A
`
`Abort Connection
`
`Go to step #999
`
`Microsoft Corporation
`Exhibit 1016-00021
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8,2003
`
`Sheet 19 of 32
`
`US 6,546,425 B1
`
`650
`
`
`"Event—
`Retransmit
`
`
`expired!
`
`
`timer
`
`
`
`651
`
`N" Any
`
`outstanding
`
`
`frames
`
`652
`
`
`
`entire retransmit
`penod
`
`
`expired?
`
`654
`
`Steep for difference
`in time
`
`
`
`
`
`
`
`
`
`Total retransmit
`period
`
`exphed?
`
`State
`Dormant
`
`657
`
`65
`
`8
`
`659
`
`No
`
`No
`
`656B
`
`Reprocess frame to remove
`any expired data
`
`Abort Connection
`Go to step #999
`
`Retransmit Frame
`
`Restart retransmit
`
`timer
`
`660
`
`Fig. 12
`
`Retransmit Event Logic
`
`Microsoft Corporation.
`Exhibit 1016-00022
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`2whS
`
`1B524,6
`
`r.M3mNnbaxm_Mm:_:Eo
`
`commubaxm8mmubaxm
`a“:EQDE338
`
`Sam
`
`m<N_.OEm1........J380
`
`0com
`
`em26:0fogE2.
`flmom”-3wDom—Cvmom
`
`
`onanogum
`
`as:
`
`
`
`4.:am_—W238Eam—5fi,mNF0_H_0*23mm"32%.”.Ste“.15:£no;Avwom
`S_.Uxxx88:33onficaooEmaT238SumxuzaooSumancaoo3mm.
`
`
`:58:“QDomEcon
`
`Microsoft Corporation
`Exhibit 1016-00023
`
`Microsoft Corporation
`
`
`
`
`

`

`US. Patent
`
`Apr. 8, 2003
`
`Sheet 21 of 32
`
`US 6,546,425 B1
`
`
`
`Om_..OE
`
`non
`
`oom
`
`a2_
`
`Levon:
`
`x¥mocmzuom
`
`E38$28can338%N¥30m
`
`0th305%
`
`quaoobfim
`
`1*Don
`
`xnycgouSum
`
`c*as;
`
`men:as.hoco_mm_Em:o:mm
`N§DanI:mum;2Sum
`onEzoo90m
`
`cmam;2Sum
`
`.mon
`
`
`
`hovum:a2_
`
`xwmocmzumm
`
`.oom
`
`
`
`booingmEomn=2_
`
`Microsoft Corporation
`
`Exhibit 1016-00024
`
`Microsoft Corporation
`
`
`
`
`
`
`
`
`
`
`

`

`US. Patent
`
`Apr. 8,2003
`
`Sheet 22 of 32
`
`US 6,546,425 B1
`
` —Event—
`
`Receive IMP frame
`
`
`event from network!
`
`
`670
`
`Pre—validate IMP Frame
`
`671
`
`
`
`Yes
`
`Yes
`
`673
`
`
`
`
`Connection
`associated with
`
`
`frame?
`
`
`
`No
`
`674
`
`672
`
`Discard @frame
`
`67
`
`7
`
`Place on connection receive queue
`
`Place on global
`
`receive queue
`
`578
`
`675
`
`Mark connection eligible to receive
`
`Place receive queue on global work queue
`
`675
`
`Place connection on global work queue
`
`57g
`
`Signal global work event
`
`FIG. 13A
`
`Receive Event Logic
`
`Microsoft Corporation
`Exhibit 1016-00025
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8, 2003
`
`Sheet 23 of 32
`
`US 6,546,425 B1
`
`Dispatch receive eligible
`from global work queue
`
`Dequeue frame from receive queue
`
`
`
`682
`
`681
` Frame
`dequeued
`
`?
`
`
`
`
`N0
`
`Sleep waiting
`for more work.
`(30 to step #1012
`
`Validate IMP received frame
`
`685
`
`Discord Frame
`
`84
`
`686
`
`IMP
`frame ok?
`
`No
`
`Yes
`
` Connection
`
`assomoted
`
`Yes
`
`688
`
`689
`
`Process Passive Connection
`request. Go to step #720
`
`
`
`690
`
`Yes
`
`Parse lMP frame
`
`691
`
`
`
`on IMP abort
`
`
`No
`
`Yes
`
`
`
`691A
`
`Abort Connection
`Go to step #999
`
`0
`
`Fig. 133
`
`Microsoft Corporation.
`Exhibit 1016-00026
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8,2003
`
`Sheet 24 0f 32
`
`US 6,546,425 B1
`
`592
`
`info and release
`Process acknowledgement
`any outstanding send frames
`
`FIG. 13C
`
`Post frame to security subsystem
`for possible decryption
`
`694
`
`Process any control data
`
`695
`
`
`
`Any
`application
`
`
`data?
`
`
`596
`
`
`
`_ueuedata to-pplicationlayer
`
`697A
`
`697
`
`
`
`
`
`Change state
`back to
`Established
`
`698
`
`
`Yes
`
`699
`
`IndIcate dIsconnect
`to
`
`
`applIcatIon layer
`
`
`699A
`
`State Mortis
`
`
`
`
`
`
`N0
`
`700
`
`703
`
`
`
`Possibly
`Yes
`
`
`Post Mortum
`frame?
`
`
`
`700A
`
`State Post Mortum
`
`701
`
`
`
`Send IMP Post Morturn Frame
`
`
`
`
`
`_elease-esourcesconnection
`
`
`
`
`Sleep waiting for more work
`Return to global work dispatcher
`
`No
`
`702
`
`704’
`
`\ Go to step 680
`
`
`
`Microsoft Corporation.
`Exhibit 1016-00027
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8, 2003
`
`Sheet 25 of 32
`
`US 6,546,425 B1
`
`720
`
`
`
`
`
`Is
`
`
`there another
`Is_ _
`the initial
`it
`connection for this
`
`
`
`connechon
`
`
`device?
`
`Abort Connection
`Coll step #999
`
`
`
`
`
`
`No
`
`723
`
`
` Do
`
`sequence and
`connection ID
`
`
`match?
`
`
`Yes
`
`Duplicate frame
`Discord
`
`724
`
`725
`
`726
`
`Go to step 680
`
`
`
`
`—Errorw—
`Allocate
`Out of resources
`connection
`resources?
`
`
`No
`
`7 7
`2
`
`726A
`
`730
`
`731
`
`
`
`Abort connection request
`
`729
`
`
`
`
`
`Did
`security
`
`
`succeed?
`
`
`Yes
`
`FIG. 14A
`
`0 Passive Connection request
`
`logic
`
`Microsoft Corporation
`Exhibit 1016-00028
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8, 2003
`
`Sheet 26 of 32
`
`US 6,546,425 B1
`
`7.32
`
`Send IMP establish Frame
`
`State Established
`
`732A
`
`733
`
`Start retransmitter
`
`734
`
`
`Wait
`For authentication process to
`
`conclude. Return-to global dispatcher
`
`
`
`
`
`
`735
`
`
`
`authenticated?
`
`Device
`and user
`
`No
`
`
`
`Yes
`
`736
`
`Abort Connection
`Go to step #999
`
`737
`
`738
`
`Indicate connection to
`listening application
`
`t‘
`f'
`G t
`e CO“ Iguro l0"
`
`739
`
`
` Did
`configuration
`
`and connect
`indication
`succeed?
`
`
`
`741
`
`Yes
`
`740
`
`No
`
`Abort Connection
`Go to step #999
`
`Sleep waiting for more work
`Return to global dispatcher
`
`F lG. 148
`
`Microsoft Corporation.
`Exhibit 1016-00029
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8, 2003
`
`Sheet 27 of 32
`
`US 6,546,425 B1
`
`999
`
`1000
`
`_
`Abart Connection request
`
`Dispatched
`Abort Connection request
`
`No
`
`Yes
`
`Save original state
`
`1001
`
`Connecfion
`associated
`
`with
`request?
`
`
`
`
`
`
`Connection
`indicated to listen
`
`application
`
`1)
`
`
`State Abort
`
`1002A
`
`1 004
`
`Yes
`
`Indicate disconnection to
`listening application
`
`
`
`State Post Mortem
`
`
`
`Release connection resources
`
`
`
`
`Original
`state>
`State Pending
`
`?
`
`Yes
`
`1007
`
`No
`
`Go to step #1012
`
`0
`
`FIG. 15A
`Abort Connection request
`
`logic
`
`Microsoft Corporation.
`Exhibit 1016-00030
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8,2003
`
`Sheet 28 of 32
`
`US 6,546,425 B1
`
`
`
`Yes
`
`Abort
`
`Frame
`
`
`
`1 008
`
`
`Is
`IMP
`it on IMP
`
`
`Frame
`
`assocmted?
`
`
`1011
`
` Discord Frame
`
`Send IMP Abort Frame
`
`
`
`Return to coliing routine
`
`1012
`
`FIG. 158
`
`Microsoft Corporation,
`Exhibit 1016—00031
`
`Microsoft Corporation
`
`

`

`US. Patent
`
`Apr. 8, 2003
`
`Sheet 29 0f 32
`
`US 6,546,425 B1
`
`mom
`
`Ennis:Qco.cuomc§593$
`
`$33.3Exn§§90>me
`
`Loxoom
`
`
`
`
`toBEE3c8ES39.Solmfic500E:
`
`
`Baum.as5.;23.68%$28.3Emma3mmABESana
`
`
`
`gmhmm92.3a\onaught—x$9528
`
`vow
`
`
`
`33mm:6:on$qu:8:
`
`:mEmm
`
`
`
`
`
`mogayonbmOtuo.chym:QOIQ9.0E
`
`
`
`3.5K:338wemca
`
`Microsoft Corporation,
`Exhibit 1016-00032
`
`Microsoft Corporation
`
`
`
`

`

`US. Patent
`
`Apr. 8, 2003
`
`Sheet 30 of 32
`
`US 6,546,425 B1
`
`m8EuaBeamEm5
`
`wow
`
`a\mom
`
`
`
`
`
`::
`
`
`
`Egon..E2_u._azugmE8;atommzmumm
`
`t.5
`
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`US 6,546,425 B1
`
`1
`METHOD AND APPARATUS FOR
`PROVIDING MOBILE AND OTHER
`IN'I‘ERIVII’ITICN’I‘ CONNECTIVI'I‘Y IN A
`COMPUTING ENVIRONMENT
`
`CROSS-REFERENCE TO RELATED
`APPLICATIONS
`
`This application claims priority from provisional appli—
`cation No. 60/103,598 filed Oct. 9, 1998 entitled “Method
`and Apparatus For Providing Wireless Connectivity In A
`Computing Environment” (which provisional application is
`incorporated by reference herein in its entirety).
`FIELD OI-‘ THE INVENTION
`
`10
`
`invention relates to connectivity between
`The present
`networked computing devices. More particularly,
`the
`present invention relates to methods and systems that trans-
`parently address the characteristics of nomadic systems, and
`enable existing network applications to run reliably in the
`associated mobile environments. Still more particularly, the
`invention relates to techniques and systems for providing a
`continuous data stream connection between intermittently—
`connected devices such as handheld data units and personal
`computing devices.
`BACKGROUND AND SUMMARY OF THE
`INVENTION
`
`Increasingly, companies are seeing rapid access to key
`information as the way to maintaining a competitive advan-
`tage. To provide immediate access to this information,
`mobile and other
`intermittently-connected computing
`devices are quietly and swiftly becoming an essential part of
`corporate networks—especially with the proliferation of
`inexpensive laptops and hand-held computing devices.
`However, integrating these nomadic devices into existing
`network infrastructures has created a challenge for
`the
`information manager,
`Many problems in mobile networking parallel the diffi-
`culties in early local area networks (LANs) before the
`adoption of Ethernet. There are a variety of mobile protocols
`and interfaces, and because standards are just developing,
`there is little interoperability between systems. In addition,
`performance over
`these network technologies has been
`typically slow and bandwidth limited. Implementation costs
`to date have been high due the specialized nature of
`deployed systems.
`Along with these issues, mobile technologies present a
`category of problems unto their own. Interconnects back
`into the main network may travel over and through a public
`network infrastructure, thus allowing sensitive information
`to possibly be tapped into. Furthermore,
`if any of the
`intermediary interconnects are via a wireless interface, the
`information is actually broadcast, and anyone with a similar
`interface can eavesdrop without much difficulty.
`But, perhaps even more significantly, mobile networking
`has generally in the past been limited to mostly message-
`oriented or state-less applications—and thus has not been
`readily adaptable for existing or new corporate applications
`that use client/server, host-terminal, web-based or shared file
`systems models. This is because such commonly used
`applications need stateful sessions that employ a continuous
`stream of data—not just a stateless packet exchange—to
`work effectively and reliably.
`To this end, many or most popular olf-the-shelf network-
`ing applications require TCP/IP sessions, or private virtual
`
`40
`
`60
`
`0(1|
`
`2
`circuits. These sessions cannot continue to function if they
`encounter network interruptions,