(12)
`
`United States Patent
`'I‘urner et al.
`
`(10) Patent No.:
`
`(45) Date of Patent:
`
`US 7,218,722 B1
`May 15, 2007
`
`US007218722B1
`
`5.930.700 A *
`5.933.483 A
`6.002.759 A
`6.009.160 A
`6.014.560 A
`6.021.126 A
`6.088.687 A *
`6.252.952 B1‘
`6.493.760 Bl “
`
`.......... .. 45.51435.3
`711999 Pepper et al.
`8.11999 Pellegrino et al.
`........ .. 3791201
`12.11999 Kallioniemi et al.
`..... .. 3791220
`12.11999 Sonnenherg .............. .. 3791220
`1.12000 Kramer
`. . . . . . . . .
`. . . . . .. 4551414
`2.12000 White et al.
`3701352
`712000 l.e1eu . . . . . . . . . . . .
`. . . . . .. 70.51400
`612001 Kung etal.
`3791114.!
`12.12002 Pendlebury et :11.
`70‘):“22‘)
`
`
`
`(Continued)
`FOREIGN PATENT DOCUMENTS
`
`CA
`
`2269584
`
`1111999
`
`(Continued)
`
`Primary E_\‘aminer—Fan Tszmg
`Assistant E.\'aminer#Md S. Elahee
`
`(74) Attorney. Agent. or Firm
`Hulbert & Berghotl‘ 1.1.1’
`
`(57)
`
`ABSTRACT
`
`McDonnell Boehnen
`
`A system and method for providing call management ser-
`vices in a Virtual Private Network of the present invention
`uses the advantages of end-to-end Internet Protocol signal-
`ing. The system and method of the present
`invention
`includes a user profile which oflers both a customer address
`and a user name as search keys. The method includes
`locating the called party who may be at a multiplicity of
`possible physical locations. evaluating the calling and called
`party privileges. routing preferences and busy/idle status for
`establishing permission to set up the call. determining an
`optimum route to establish the telephone call. Due to the
`system and method of the present invention. the telephone
`call takes the optimum route and preferably the most direct
`route to the destination with a high probability of comple-
`non.
`
`4 (flaims, 25 Drawing Sheets
`
`‘____,,1o
`
`(54)
`
`(75)
`
`SYSTEM AND METHOD FOR PROVIDING
`CALL MANAGEMENT SERVICES IN A
`VIRTUAL PRIVATE NETWORK USING
`VOICE OR VIDEO OVER IN'I‘ERNE'l‘
`PROTOCOL
`
`Inventors: George W. Turner. Nepean (CA):
`William J. Noll. Bristol. IL (US); Paul
`V. Harrington. Naperville. IL (US):
`Rodger D. Higgins. Aurora. IL (US)
`
`(73)
`
`Assignee: Westell Technologies, Inc.. Aurora. 11.
`(US)
`
`(*)
`
`Notice:
`
`Subject to any disclaimer. the tenn of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 1090 days.
`
`(21)
`
`Appl. No.: 09/739,716
`
`(22)
`
`Filed:
`
`Dec. 18, 2000
`
`Int. Cl.
`
`(2006.01)
`H04M 7/00
`U.S. Cl.
`.......................... .. 379/221.02: 379/211.02:
`709/204'. 370/352
`Field of Classlficatlon Search ......... .. 379/221.13.
`379/265.04. 114.1. 201.01. 211.01. 144.01.
`379/38. 211.()2. 88.01. 221.02: 7()9/318.
`709/229. 204. 227. 248: 455/445. 435.3:
`370/352. 338: 705/400
`See application file for complete search history.
`References Clted
`
`U.S. PATENT DOCUMENTS
`
`3.‘1980 Weber ....................... .. 179118
`931993 Kay et :11. .............. .. 3791207
`61995 Hasenauer et al.
`379.-‘207
`1031995 Graechter et al.
`........ .. 379.-"207
`41996 Serbetcioglu et al.
`379188.01
`231997 Ahlberget al.
`........... .. 4551445
`61998 Venier et al.
`379.-‘Z07
`41999 Turner . . . . . . . ..
`. . . .. 379.-‘220
`7“l999 Karppinen ................ .. 3791207
`
`
`
`4.191.860 A
`5.247.571 A
`5.422.941 A
`5.463.685 A
`5.511.111 A “
`5.600.704 A “
`5.768.358 A
`5.892.821 A
`5.920.619 A
`
`(51)
`
`(52)
`
`(58)
`
`(56)
`
`PIBLC SWITCIED YELEPHOFE NETVWK
`
`E
`
`SYSTEM1
`
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`
`WMAIN
`NAME
`SERVER
`
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`SERVER
`SERVER
`MALE
`SERVER
`SERVER
`SERVER
`
`
`
`CRCUIT
`SWITO-H)VRl.NK§
`
`Page 1 of 40
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`Unified Patents Exhibit 1003
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`US 7,218,722 B1
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`8/1999
`10/1999
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`9/1997
`12/1993
`12/1993
`2/1999
`4/1999
`6/1999
`7/1999
`9/1999
`10/1999
`10/1999
`10/1999
`12/1999
`
`
`
`11207422
`11289383
`9700530
`W097/33412
`W093/54363
`W093/59467
`W099/05590
`W099/21109
`W099/31862
`W099/38310
`WO99/45679
`WO99/52265
`WO99/55062
`WO99/55066
`W099/67922
`
`JP
`JP
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`WO
`
`W0
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`* cited by examiner
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`
`U.S. PATENT DOCUMENTS
`
`
`
`
`............. .. 370/338
`6,519,242 B1*
`2/2003 Emery et al.
`
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`6,629,144 B1*
`9/2003 Chu et a1.
`.... ..
`709/227
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`. 379/201.01
`6,735,292 B1*
`5/2004 Johnson
`
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`6,741,692 131*
`5/2004 Johnson
`379/211.01
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`6,751,652 B1*
`6/2004 Thomas
`709/204
`
`
`
`
`
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`2002/0010803 A1*
`1/2002 Oberstein et a1.
`......... .. 709/318
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`Ep
`
`Ep
`
`Ep
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`JP
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`
`
`
`
`FOREIGN PATENT DOCUMENTS
`0349964 A1
`6/1993
`
`
`0330255
`11/1993
`
`0951157
`10/1999
`
`0963037
`12/1999
`
`2334646
`3/1999
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`2337429
`11/1999
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`11205335
`7/1999
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`U.S. Patent
`
`Mav 15
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`US 7,218,722 B1
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`Page 4 of 40
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`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 3 of 25
`
`US 7,218,722 B1
`
`./.
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`Page 5 of 40
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`U.S. Patent
`
`May 15, 2007
`
`Sheet 4 of 25
`
`US 7,218,722 B1
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`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 5 of 25
`
`US 7,218,722 B1
`
`IIIIIIIIIIIIIIIIIIII
`
`{
`
`IIIIIIIIII IIIIIII|
`
`TRANSLATE
`CALLING
`
`NETWORK
`ADDRESS
`
`TRANSLATE
`DIALED
`CUSTOMER
`ADDRESS
`
`. — — — — — ¢ — — p — — — _._.I
`
`GENERATE
`NETWORK
`ADDRESS
`
`SEND QUERY
`TO DIRECTORY
`SERVER
`
`TO FIG. 5A AND 13A
`
`NO
`
`6‘)
`
`TO STEP 178
`
`FIG. 4A
`
`Page 7 of 40
`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 6 of 25
`
`Us 7,218,722 B1
`
`FROM STEP 176
`
`MATCHING
`DECISION
`TREE
`
`133
`
`T0 FIG. 4c
`
`NO—>®
`
`SEND A QUERY
`TO DOMAIN
`NAME SERVER
`
`{BEE/IKIT\1_rxTA_M—E_§E_RT/ER:
`I
`
`TRANSLATE
`TO INTERNET
`PROTOCOL
`
`ADDRESS
`
`SEND SETUP
`INSTRUCTIONS
`TO GATEWAY
`
`Page 8 of 40
`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 7 of 25
`
`Us 7,218,722 B1
`
`FROM FIG. 48. 5A. 68.
`
`6C, 10B AND 138
`
`19
`
`195
`
`PSTN
`NUMBER?
`
`NO
`
`up
`
`ADDRESS?
`
`was
`
`QUERY OTHER
`NETWORKS AND
`
`GET RESPONSE
`
`SEND
`INSTRUCTION TO
`THE GATEWAY
`
`EXTERNAL PSTN
`DESTINATION
`
`GETS CALL
`
`Page 9 of 40
`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 8 of 25
`
`US 7,218,722 B1
`
`FROM FIGS. 4A AND 10A
`
`GET INTERNET PROTOCOL
`ADDRESS OF CALL AGENT
`
`IN GATEWAY "Y"
`
`u'PTE§§6r7I E66;/i'r"o’R""""" ’ ' ‘
`:SERVER GATEWAY Y
`
`SEND QUERY TO
`GATEWAY "Y"
`
`MATCHING
`DECISION
`TREE
`
`NO
`
`I
`
`TO FIG. 4C
`
`216
`
`ROUTING
`DECISION
`TREE
`
`SAVE RECORD
`
`ASSIGNTOKEN
`
`ESTABLISH VOIP
`ASSOCIATION
`
`TO STEP 222
`
`FIG. 5A
`
`TO STEP 228
`
`Page 10 of 40
`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 9 of 25
`
`US 7,218,722 B1
`
`FROM STEP 219
`
`@ N
`
`O
`
`+
`
`SEND SETUP
`
`|NSTRUCTlONS
`
`TO GATEWAY
`
`FROM STEP 221
`
`SETS UP CALL
`
`PUBLIC SWITCHED
`
`TELEPHONE NETWORK
`
`GATEWAY "Y" PASSES
`REQUEST TO CALL AGENT
`
`INCOMING CALL
`
`PROCESS
`
`RECORDS
`SAVED?
`
`ETWOR '
`ADDRESS
`
`MATCH?
`
`(«E
`
`TO STEP 234
`
`Page 11 of 40
`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 10 of 25
`
`US 7,218,722 B1
`
`FROM FIGS. 6A
`AND 133
`
`FROM STEP 232
`
`Q“?
`
`MATCH
`TOKENS AND
`GET RECORDS
`
`S EN D QUERY
`TO DOMAIN
`NAME SERVER
`
`SEND SETUP
`INSTRUCTIONS
`TO GATEWAY
`
`.'E)"c)T\n7xTr~TN/§I\iE'§E'I§'\7E’F%‘a
`
`242
`
`TRANSLATE
`TO INTERNET
`PROTOCOL
`
`ADDRESS
`
`Page 12 of 40
`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 11 of 25
`
`US 7,218,722 B1
`
`
`
`PSTN CALLER DIALS
`
`262 ‘L. 260
`
`PSTN ROUTES
`CALL TO GATEWAY
`
`
`
`GATEWAY
`PASSES REQUEST
`TO CALL AGENT
`
`264
`
`266
`
`NO
`
`
`
`RECORDS SAVED?
`
`TO FIG. 5C
`
`msfi
`
`'
`
`DIRECTORY SERVER
`
`274
`
`
`
`FROM
`
`FIG. 133
`
`Page 13 of 40
`
`INTERNAL CALL?
`
`
`
`
`276
`
`MATCHING
`DECISION TREE
`
`
`
`YES
`
`é
`
`T0 STEP 290
`
`I
`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 12 of 25
`
`Us 7,218,722 B1
`
`FROM STEP 276
`
`INTERNAL
`
`CALL?
`
`T0 FIG. 4C
`
`N°"®
`
`{“D_C>_IvI_ATN_ N/TATE §E_R-V—E_R—1l
`I
`
`IIIIIIIIIII
`
`IIIIIIIIIIII
`
`SEND QUERY TO
`DOMAIN NAME SERVER
`
`I
`
`TRANSLATE
`TO INTERNET
`PROTOCOL ADDRESS
`
`SEND SETUP
`INSTRUCTIONS
`TO GATEWAY
`
`USER A
`
`GETS CALL
`
`Page 14 of 40
`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 13 of 25
`
`Us 7,218,722 B1
`
`'"'t3'I§€<;"r'oT2Vs'ET2\‘/Efi"
`
`FROM STEP 274
`
`TRANSLATE
`CALLING
`NETWORK
`ADDRESS
`
`YES
`
`W "
`
`’66rfi/TIrT1T~:'i\KnE's.'E§\7ERT ‘
`
`304
`
`TRANSLATE TO
`IP ADDRESS
`
`III II :
`
`.
`
`SEND QUERY TO
`DOMAIN NAME
`SERVER
`
`II
`
`SEND SETUP
`INTRUCTIONS
`
`TO GATEWAY
`
`USER C GETS CALL
`
`Page 15 of 40
`
`

`
`U.S. Patent
`
`May 15,2007
`
`Sheet 14 of 25
`
`Us 7,218,722 B1
`
`FROM FIG. 4A
`
`SEND SETUP
`
`INSTRUCTIONS TO
`
`GATEWAY
`
`PSTN SUBSCRIBER
`
`GETS CALL
`
`Page 16 of 40
`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 15 of 25
`
`Us 7,218,722 B1
`
`BRANCH 1.1
`
`T0 STEP 366
`
`LEVEL
`
`356
`
`RETURN VOICE
`MESSAGING #
`
`YES
`
`' ETU RN USER'S
`HOME #
`
`Page 17 of 40
`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 16 of 25
`
`US 7,218,722 B1
`
`FROM STEP 354
`
`
`
`CLOSED
`BUSINESS
`UNIT?
`
`NO
`
`
`
`366
`
`
`
`
`
`RETURN VOICE
`MESSAGING #
`
`368
`
`370
`
`CALLING >
`CALLED?
`
`NO
`
`372
`
`YES
`
`
`
`374
`
`
`
`SET BARGE-IN FLAG
`
`376
`
`RETURN THE NA #
`
`-
`
`- 1
`
`373
`
`
`
`NO
`
`330
`
`YES
`
`382
`
`TREATMENT CODE
`
`
`
`SETUP RING AGAIN
`WITH RESERVATION
`
`
`
`Page 18 of 40
`
`

`
`U.S. Patent
`
`May 15,2007
`
`Sheet 17 of 25
`
`Us 7,218,722 B1
`
`START
`
`/ 400
`
`402
`
`NO
`
`NO
`
`YES
`
`YES
`
`408
`
`TRUNKS
`VAILABLE
`
`
` ' ESERVAT!O
`
` 410
`
`
`406
`
`
`
`414
`
`RETURN
`CHOICE = PST
`
`
`
`
`
` yes
`
`RETURN
`CHOICE = VOIP
`
`416
`
`N0
`
`413
`
`CHOlCE=FALSE
`
`FIG. 8
`
`Page 19 of 40
`
`
`PRIVILEGE?
`
`
`NO
`
`407
`
`RETURN
`
`CHOICE = PST
`
`412
`
`EXPENSIVE
`
`' OUTE OPTIO
`
`YES
`
`
`
` SET
`RESERVATION
`
`FLAG
`
`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 18 of 25
`
`US 7,218,722 B1
`
`
`
`450\
`
`452
`
`DIRECTORY SERVER
`GETS QUERY
`
` FROM FIG. 12
`GET CURRENTLY
`ASSIGNED CUSTOMER
`
`ADDRESS FROM
`
`NETWORK ADDRESS
`
`GET CALLER'S PROFILE
`
`
`
`454
`
`456
`
`460
`
`T
`
`YES
`
`NO
`
`
`SET
`TREATMENT
`CODE
`
`
`454
`
`NO
`
`PERFORM
`
`LOOKUP
`
`458
`
`466
`
`
`
`
`
`DIALED
`NUMBER
`CREENED7
`
`
`
`
`
`
`
`SET
`
`TREATMENT
`CODE
`
`
`
`
`
` TRANSLATE CALLER'S
`NETWORK ADDRESS AND
`DIALED # AS REQUIRED
`
`RESPOND TO QUERY
`
`FIG. 9
`
`Page 20 of 40
`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 19 of 25
`
`Us 7,218,722 B1
`
`GATEWAY PASSES
`REQUEST TO
`LOCAL CALL AGENT
`
`YES
`
`WYES
`
`MATCHING
`DECISION TREE
`
`E
`
`528
`
`TO STEP 530
`
`FIG. 10A
`
`Page 21 of 40
`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 20 of 25
`
`Us 7,218,722 B1
`
`FROM STEP 528
`
`SEND QUERY TO
`DOMAIN NAME
`SERVER
`
`GET USERS
`CUSTOMER
`ADDRESS -
`
`SET UP
`ASSOCIATION WITH
`
`PORTABILITY SERVER
`
`SEND QUERY
`
`TO DIRECTORY
`
`SERVER
`
`{_D|_R—E—CTORY— §ER\7E'R“.
`
`.
`
`/' 540
`
`ASSWOR
`.
`
`GET USER'S
`PASSWORD
`
`TOSTEP546
`
`Page 22 of 40
`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 21 of 25
`
`US 7,218,722 B1
`
`FROM STEP 544
`
`G 546,
`
`YES
`
`550
`
`SEND MESSAGE
`TO DIRECTORY
`
`SERVER
`
`{"'c>‘::ie‘6T’c1'R§"s'ET2?/E1$""
`
`UPDATE PROFILE AND
`NETWORK ADDRESS
`
`BROAD CAST
`
`YES
`
`ADVISE USER
`
`OF SUCCESS
`
`Page 23 of 40
`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 22 of 25
`
`Us 7,218,722 B1
`
`START / 600
`
`DIRECTORY sERvER GETS QUERY
`
`602
`
`GET CURRENT CUSTOMER ADDRESS
`FROM NETWORK ADDRESS
`
`GET CALLER'S PROFILE
`
`APPLY TRANSLATION DEC IONIS
`
`
`TREE
`
`61
`
`SET
`
`TREATMENT
`CODE
`
`_
`TRANSLATE CALLER s NETWORK
`ADDRESS AND DIALED NUMBER
`
`AS REQUIRED
`
`RESPOND TO QUERY
`
`Page 24 of 40
`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 23 of 25
`
`US 7,218,722 B1
`
`
`
`@<~No
`
`EXTERNAL CALL?
`
`YES
`
`ROAMED?
`
`YES
`
`TO FIG. 9
`
`
`
`
`
`GET ASSIGNED CUSTOMER
`ADDRESS
`
`GET CALLED USER'S PROFILE
`
`
`
`NO
`
`GET CURRENT NETWORK ADDRESS
`
`SUBSITUTE CURRENT
`NETWORK ADDRESS FOR
`DIALED NETWORK ADDRESS
`
`RESPOND TO QUERY
`
`FIG. 12
`
`Page 25 of 40
`
`DIRECTORY SERVER GETS QUERY
`
`/ 650
`
`
`654
`
`658
`
`662
`
`552
`
`664
`
`666
`
`568
`
`670
`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 24 of 25
`
`US 7,218,722 B1
`
`FROM FIG. 4A
`
`GET IP ADDRESS OF
`THE CALL AGENT IN
`GATEWAY Y
`
`SEND QUERY TO
`GATEWAY "Y"
`
`4---'’'’'/’’ 700
`
`702
`
`MATCHING
`DECISION
`TREE
`
`SEND SETUP
`INSTRUCTIONS
`TO GATEWAY
`
`PUBLIC SWITCHED
`TELEPHONE NETWORK
`SET UP CALL
`
`TO STEP 722
`
`FIG. 13A
`
`Page 26 of 40
`
`

`
`U.S. Patent
`
`May 15, 2007
`
`Sheet 25 of 25
`
`US 7,218,722 B1
`
`FROM STEP 720
`
`GATEWAY "Y"
`PASSES REQUEST
`TO CALL AGENT
`
`724 :D|RECTORY
`I SERVER
`
`’ ECORD SAVED?
`
`NO
`
`O
`
`728
`
`SEND QUERY TO
`
`DIRECTORY SERVER
`
`YES
`
`MATC H I N G
`DECISION TREE
`
`TRANSLATE
`CALLING
`N ETWORK
`ADDRESS
`
`GET
`PROFILE
`DATA
`
`ADDRESS
`MATCH?
`
`NO
`
`744
`
`YES
`
`745
`
`W No@
`
`TO FIG. 40
`
`746 ———————————— --
`IDDMAIN NAME sERvER‘.
`
`748
`
`TRANSLATE
`TO INTERNET
`PROTOCOL
`ADDRESS
`
`FIG. 13B
`
`YES
`
`SEND QUERY TO
`DOMAIN NAME
`
`SERVER
`
`SEND SETUP
`INSTRUCTION
`TO GATEWAY
`
`Page 27 of 40
`
`

`
`
`
`US 7,218,722 B1
`
`
`
`
`1
`SYSTEM AND METHOD FOR PROVIDING
`
`
`
`
`CALL MANAGEMENT SERVICES IN A
`
`
`
`
`
`VIRTUAL PRIVATE NETWORK USING
`
`
`
`
`VOICE OR VIDEO OVER INTERNET
`
`
`
`
`PROTOCOL
`
`
`
`
`
`
`
`FIELD OF THE INVENTION
`
`
`
`
`
`
`This present invention relates to a system and method for
`
`
`
`
`
`
`
`
`
`
`providing communication services over a network. More
`
`
`
`
`
`
`
`specifically,
`it relates to Call Management Services in a
`
`
`
`
`
`
`
`
`
`Virtual Private Network using Voice or Video over Internet
`
`
`
`
`
`
`
`
`
`Protocol.
`
`
`BACKGROUND OF THE INVENTION
`
`
`
`
`
`
`Call Management Services (CMS) allow the calling and
`
`
`
`
`
`
`
`
`called parties to exercise control over call set-up functions
`
`
`
`
`
`
`
`
`
`within a network. Call set-up includes dialing, wait time and
`
`
`
`
`
`
`
`
`
`time to move through central ofiices and long distance
`
`
`
`
`
`
`
`
`
`services. Typically, there are both originating and terminat-
`
`
`
`
`
`
`
`ing versions of these Call Management Services. Originat-
`
`
`
`
`
`
`
`ing versions address decisions such as which route to take to
`
`
`
`
`
`
`
`
`
`
`
`complete the call, or what action to take upon encountering
`
`
`
`
`
`
`
`
`
`
`a busy signal. Terminating versions include the ability to
`
`
`
`
`
`
`
`
`
`selectively ignore calls, or route them to a handling mecha-
`
`
`
`
`
`
`
`
`
`nism. The handling mechanism provides for a treatment for
`
`
`
`
`
`
`
`
`
`a call and results in an outcome other than a successful call
`
`
`
`
`
`
`
`
`
`
`
`completion to the desired party. It includes, but is not limited
`
`
`
`
`
`
`
`
`
`
`
`to a busy signal, message service, attendant or administra-
`
`
`
`
`
`
`
`
`tive assistant answering.
`
`
`
`Call Management Services are widely deployed in the
`
`
`
`
`
`
`
`
`Public Switched Telephone Network, having been marketed
`
`
`
`
`
`
`
`for many years under the acronym CLASSSM, which stands
`
`
`
`
`
`
`
`
`
`for Custom Local Area Signaling Services. Most private
`
`
`
`
`
`
`
`
`networks, such as Virtual Private Networks (VPN), have
`
`
`
`
`
`
`
`
`deployed proprietary versions of these services, which func-
`
`
`
`
`
`
`
`tion in an equivalent manner using capabilities of the current
`
`
`
`
`
`
`
`
`
`
`Signaling System 7 (SS7). Virtual Private Networking is a
`
`
`
`
`
`
`
`
`
`widely deployed generic business service offering which
`
`
`
`
`
`
`
`provides customers with a closed user group environment
`
`
`
`
`
`
`
`
`across a plurality of physical locations. There are several
`
`
`
`
`
`
`
`
`
`subsets of Virtual Private Networking, one of the better-
`
`
`
`
`
`
`
`
`known being Wide Area Centrex (WAC). The CLASS
`
`
`
`
`
`
`
`services include Automatic Recall (AR), Automatic Call-
`
`
`
`
`
`
`back (AC), Selective Call Forwarding (SCF), Selective Call
`
`
`
`
`
`
`
`Acceptance, Selective Call Rejection (SCR), and the varia-
`
`
`
`
`
`
`
`tions thereof. Automatic Callback and Automatic Recall are
`
`
`
`
`
`
`
`similar services. Automatic Recall attempts to call back the
`
`
`
`
`
`
`
`
`last party who called the customer, where as Automatic
`
`
`
`
`
`
`
`
`Callback is invoked during an initial attempt by the cus-
`
`
`
`
`
`
`
`
`
`tomer when a busy line is encountered. Automatic Recall is
`
`
`
`
`
`
`
`
`
`typically not used in private networks since these networks
`
`
`
`
`
`
`
`
`
`strive to provide a correct disposition for all incoming calls.
`
`
`
`
`
`
`
`
`
`Traditional Call Management Services suffer from several
`
`
`
`
`
`
`
`serious shortcomings such as:
`
`
`
`
`
`
`
`
`
`
`
`
`
`l) the features are invoked after the network has made major
`
`
`
`
`
`
`
`
`
`
`
`routing decisions, for example, a call is allowed to progress
`
`
`
`
`
`
`
`
`
`
`through the network to the called party’s line before it is
`
`
`
`
`
`
`
`
`
`
`
`redirected;
`
`2) the features recognize calling and called network inter-
`
`
`
`
`
`
`
`
`face points or endpoints instead of specific users, making
`
`
`
`
`
`
`
`
`them useless and inappropriate in an environment where
`
`
`
`
`
`
`
`users roam amongst a multiplicity of network interface
`
`
`
`
`
`
`
`points; 3) the end-to-end signaling capability is limited by
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`Page 28 of 40
`
`10
`
`
`
`15
`
`
`
`20
`
`
`
`25
`
`
`30
`
`
`
`35
`
`
`
`40
`
`
`
`45
`
`
`
`50
`
`
`
`55
`
`
`
`60
`
`
`
`65
`
`
`2
`
`
`antiquated technology; and 4) service portability, the ability
`
`
`
`
`
`
`
`to roam while retaining access to personalized CMS fea-
`
`
`
`
`
`
`
`
`tures, is not supported.
`
`
`
`
`Several Voice or Video over Internet Protocol (VoIP)
`
`
`
`
`
`
`
`telephony solutions have been proposed and/or imple-
`
`
`
`
`
`
`mented. However, these solutions tend to emphasize the new
`
`
`
`
`
`
`
`
`capabilities provided by Internet Protocol technology, such
`
`
`
`
`
`
`as multimedia integration, rather than addressing improve-
`
`
`
`
`
`
`ments to existing call-based services. Moreover, these solu-
`
`
`
`
`
`
`
`tions often introduce questionable practices which may
`
`
`
`
`
`
`
`undermine the Quality of Service (QoS) to which business
`
`
`
`
`
`
`
`
`
`customers have become accustomed. Overly aggressive,
`
`
`
`
`
`
`compression of bandwidth, lack of regard for the scarcity of
`
`
`
`
`
`
`
`
`
`
`global Internet Protocol addresses, or alerting the target
`
`
`
`
`
`
`
`
`station or endpoint before call completion is guaranteed are
`
`
`
`
`
`
`
`
`
`a few examples of some of the issues that result from current
`
`
`
`
`
`
`
`
`
`
`
`
`solutions.
`
`Therefore, it is desirable to enhance Call Management
`
`
`
`
`
`
`
`Services to overcome various shortcomings of the present
`
`
`
`
`
`
`
`day services and to extend these enhancements to cover new
`
`
`
`
`
`
`
`
`
`multimedia calls, without jeopardizing Quality of Service
`
`
`
`
`
`
`(QoS).
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`SUMMARY OF THE INVENTION
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`The system and method of the present invention takes full
`
`
`
`
`
`
`
`
`
`
`advantage of end-to-end Internet Protocol signaling in order
`
`
`
`
`
`
`
`
`to enhance Call Management Services capability for both
`
`
`
`
`
`
`
`
`calling and called parties. This is accomplished while allow-
`
`
`
`
`
`
`
`
`ing the user continued use of a conventional circuit-switched
`
`
`
`
`
`
`
`voice transport network, such as the Public Switched Tele-
`
`
`
`
`
`
`
`
`phone Network (PSTN), to guarantee the Quality of Service
`
`
`
`
`
`
`
`
`(QoS) that Virtual Private Network (VPN) users have come
`
`
`
`
`
`
`
`
`to expect.
`
`
`The system and method of the present invention users a
`
`
`
`
`
`
`
`
`
`two-layer numbering scheme. The first or lower layer com-
`
`
`
`
`
`
`
`
`prises the Directory Numbers from the North American
`
`
`
`
`
`
`
`
`Numbering Plan (NANP), as assigned by a Local Exchange
`
`
`
`
`
`
`
`
`Carrier (LEC) or a neutral Industry number administrator.
`
`
`
`
`
`
`
`
`These may be, for example, geographic numbers, perma-
`
`
`
`
`
`
`
`nently associated with a specific rate center. This base layer
`
`
`
`
`
`
`
`
`is translated into a physical local Internet address associated
`
`
`
`
`
`
`
`
`with an endpoint or other network termination point within
`
`
`
`
`
`
`
`
`the VPN. The second or higher layer of numbers identifying
`
`
`
`
`
`
`
`
`
`individual users, are assigned by the customer’s administra-
`
`
`
`
`
`
`
`tor, and remain with these users wherever they are located in
`
`
`
`
`
`
`
`
`
`
`
`the network. The Directory Numbers (DN) are also the
`
`
`
`
`
`
`
`
`
`Network Addresses (NA). The artificial numbers assigned to
`
`
`
`
`
`
`
`
`specific users are the Customer Addresses (CA). A Directory
`
`
`
`
`
`
`
`
`
`Server performs the translation from Customer Address to
`
`
`
`
`
`
`
`
`Network Address and vice versa.
`
`
`
`
`
`The system and method of the present invention includes
`
`
`
`
`
`
`
`
`
`a user profile which offers both the Customer Addresses
`
`
`
`
`
`
`
`
`
`(CA) and the user name as search keys. These fields are
`
`
`
`
`
`
`
`
`
`
`
`linked and normalized within the signaling mechanism to
`
`
`
`
`
`
`
`
`the CA which allows the calling and called users to opt for
`
`
`
`
`
`
`
`
`
`
`
`
`the identifier of their choice. In addition, a caller with an
`
`
`
`
`
`
`
`
`
`
`
`appropriate alphanumeric terminal can enter user names
`
`
`
`
`
`
`
`instead of Customer Addresses to reach the called party.
`
`
`
`
`
`
`
`
`
`In accordance with a preferred embodiment, the method
`
`
`
`
`
`
`
`
`for providing Call Management Services in a Virtual Private
`
`
`
`
`
`
`
`
`Network using Voice or Video over Internet Protocol (VoIP)
`
`
`
`
`
`
`
`
`
`includes a multi-step process for setting up a call, which is
`
`
`
`
`
`
`
`
`
`
`
`assumed to involve customers located at two different pri-
`
`
`
`
`
`
`
`
`vate network switching nodes. It should be noted that VoIP
`
`
`
`
`
`
`
`
`
`may also include a hybrid call comprising voice, video and
`
`
`
`
`
`
`
`
`
`data elements. The method includes locating the called party
`
`
`
`
`
`
`
`
`
`
`
`
`
`Page 28 of 40
`
`

`
`
`
`US 7,218,722 B1
`
`
`
`
`FIGS. 10A—10C are flowcharts illustrating a method for
`
`
`
`
`
`
`
`
`implementing service portability in accordance with a pre-
`
`
`
`
`
`
`
`ferred embodiment of the present invention;
`
`
`
`
`
`
`FIG. 11 is a flowchart illustrating a method for imple-
`
`
`
`
`
`
`
`
`
`menting service portability for an outgoing call in accor-
`
`
`
`
`
`
`
`
`dance with a preferred embodiment of the present invention;
`
`
`
`
`
`
`
`FIG. 12 is a flowchart illustrating a method for imple-
`
`
`
`
`
`
`
`
`
`menting service portability for an incoming call from a
`
`
`
`
`
`
`
`
`Public Switched Telephone Network using a Directory
`
`
`
`
`
`
`Server process in accordance with a preferred embodiment
`
`
`
`
`
`
`of the present invention; and
`
`
`
`
`
`FIGS. 13A and 13B are flowcharts illustrating a method
`
`
`
`
`
`
`
`
`for default routing upon Internet Protocol
`(IP) network
`
`
`
`
`
`
`
`failure in accordance with a preferred embodiment of the
`
`
`
`
`
`
`
`
`present invention.
`
`
`4
`
`
`
`
`
`
`
`
`
`
`
`
`
`DETAILED DESCRIPTION OF PREFERRED
`
`
`EMBODIMENTS
`
`
`
`
`The present invention is directed to a system and method
`
`
`
`
`
`
`
`
`
`
`for providing Call Management Services (CMS) in a Virtual
`
`
`
`
`
`
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`Private Network (VPN) using Voice or Video over Internet
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`Protocol (VoIP). It should be noted that “VoIP” refers to
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`voice or video over Internet Protocol, or a hybrid call
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`comprising voice, video, and data elements. Virtual Private
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`Network system and method using Voice over Internet
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`Protocol is described in an application by George W. Turner
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`et al., filed on Aug. 10, 2000 which corresponds to U.S. Ser.
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`No. 09/636,192, the entire teachings of which is incorpo-
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`rated herein by reference.
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`Call Handling Network Topology
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`FIG. 1 is a diagram illustrating network topology of the
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`system 10 for providing Call Management Services in a
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`Virtual Private Network in accordance with a preferred
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`embodiment of the present
`invention. The system and
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`method of the present invention describes the handling of
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`calls that originate and terminate within an exemplary
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`Virtual Private Network such as, for example, Centrex. For
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`the sake of demonstrating the features of the system, it is
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`assumed that at least two of the users are at separate network
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`nodes and that the Public Switched Telephone Network
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`(PSTN) circuit-switched network 12 is a call routing option
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`between these nodes. The nodes are assumed to have a
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`one-to-one relationship with PSTN exchanges, and more
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`specifically with a single Centrex switch, although an actual
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`solution is not
`limited by such constraints. It is further
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`assumed that it is a requirement that callers be identified by
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`number and name, both being addresses that can be called
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`back.
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`User “A” 34 has a Network Address (NA) of 313-555-
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`2001 and a Customer Address (CA) of 2001. User “B” 36
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`has a NA of313-555-2002 and a CA of 2002. User “C” 38
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`is in a different Numbering Plan Area (NPA) and has a NA
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`of 709-555-3001 and a CA of 3001. Different NPAs are
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`selected to emphasize the geographic separation of parties
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`“A” and “C”. In a preferred embodiment, although the last
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`four digits of the NA and the CA are the same for the three
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`users, there is no fixed relationship between the numbers, as
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`is the case with traditional Centrex.
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`Users “A” 34 and “B” 36 are served by an Internet
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`Protocol (IP) gateway “X” 14 whereas user “C” 38 is served
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`by IP gateway “Y” 16. The gateways depicted herein by a
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`single block may comprise a multiplicity of separate resi-
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`dential and trunk gateways, as well as a separate signaling
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`gateway. Communication between the residential and trunk
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`gateways is via a Real Time Protocol (RTP) running on a
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`3
`who may be at a multiplicity of possible physical locations
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`at the normal site, or in an environment where users can
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`roam; evaluating the calling and called party privileges,
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`routing preferences, and busy/idle status for establishing
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`permission, herein after known as the matching decision, to
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`set up the call; determining the optimum route, herein after
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`known as the routing decision, and the appropriate technol-
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`ogy such as, Voice or Video over Internet Protocol versus
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`Public Switched, or a hybrid of both, Telephone Network
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`(PSTN), to set up the voice and video paths; and establish
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`the voice transport path and matching the actual incoming
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`call with the anticipated call at the terminating network
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`interface point. Only in the final step of this process is there
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`an actual attempt to establish a telephone call in the con-
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`ventional sense.
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`Some of the benefits provided by the system and method
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`of the present invention include the call taking the most
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`direct route to the most appropriate destination with a high
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`probability of completion. By offering the option of either IP
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`or PSTN call completion, with equivalent feature function-
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`ality. Quality of Service is as good or better than with a
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`traditional circuit-switched Virtual Private Network. Meth-
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`ods are provided to conserve scarce global resources such as
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`PSTN Directory Numbers and global IP addresses.
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`The foregoing and other features and advantages of the
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`system and method for providing Call Management Services
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`in a Virtual Private Network using Voice or Video over
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`Internet Protocol will be apparent from the following more
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`particular description of preferred embodiments of the sys-
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`tem and method as illustrated in the accompanying drawings
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`in which like reference characters refer to the same parts
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`throughout the different views.
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`BRIEF DESCRIPTION OF THE DRAWINGS
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`invention are
`Preferred embodiments of the present
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`described with reference to the following drawings,
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`wherein:
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`FIG. 1 is a diagram illustrating a preferred embodiment of
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`the network topology of the system for providing Call
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`Management Services in a Virtual Private Network in accor-
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`dance with the present invention;
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`FIGS. 2A and 2B are diagrams illustrating the Directory
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`Server data structure in accordance with a preferred embodi-
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`ment of the present invention;
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`FIG. 3 is a diagram illustrating Directory Server transla-
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`tions and attribute fields in accordance with a preferred
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`embodiment of the present invention;
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`FIGS. 4A4lC are flowcharts illustrating a method for
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`handling intra-gateway calls in accordance with a preferred
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`embodiment of the present invention;
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`FIGS. 5A—5C are flowcharts illustrating a method for
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`handling inter-gateway calls in accordance with a preferred
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`embodiment of the present invention;
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`FIGS. 6A—6D are flowcharts illustrating a method for
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`handling incoming external calls in accordance with a
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`preferred embodiment of the present invention;
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`FIGS. 7A and 7B are flowcharts illustrating a method for
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`a matching decision in accordance with a preferred embodi-
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`ment of the present invention;
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`FIG. 8 is a flowchart illustrating a method for a routing
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`decision in accordance with a preferred embodiment of the
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`present invention;
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`FIG. 9 is a flowchart illustrating a method for a translation
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`decision in accordance with a preferred embodiment of the
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`present invention;
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`5
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`Page 29 of 40
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`Page 29 of 40
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`US 7,218,722 B1
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`5
`these
`managed IP network. For the sake of simplicity,
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`elements are depicted and are considered to constitute a
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`single VPN network node having one global IP address per
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`customer domain name for person locator services, as well
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`as a single SS7 point code for PSTN signaling. An IP
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`signaling protocol such as Session Initiation Protocol (SIP)
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`handles communications between the call agents 18, 26 in
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`the two gateways 14, 16, via a managed IP network 22. A
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`Media Gateway Control Protocol (MGCG), or equivalent
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`agent to client control protocol, enables control and man-
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`agement of data communications equipment operating at the
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`media gateways 14, 16 using the call agents 18, 26 as media
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`gateway controllers. Thus,
`the gateways 14, 16 are in
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`communication with their respective call agents 18, 26 using
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`MGCP. MGCP bridges between the circuit-based PSTN and
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`Internet Protocol technology based networks. For further
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`details regarding MGCP, see information available through
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`the Level 3 Communications Website at www.level3.com
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`and the Bellcore Website www.telcordia.com. While the
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`preferred embodiment is described with respect to the use of
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`MGCP, any suitable agent to client gateway contro