US0074l8504B2
`
`(12) United States Patent
`Larson et al.
`
`(10) Patent No.:
`(45) Date of Patent:
`
`US 7,418,504 B2
`Aug. 26, 2008
`
`(54) AGILE NETWORK PROTOCOL FOR SECURE
`COMMUNICATIONS USING SECURE
`DOMAIN NAMES
`
`(58) Field of Classification Search ............... .. 709/226,
`709/221; 713/201
`See application file for complete search history.
`
`(75)
`
`Inventors: Victor Larson, Fairfax, VA (US);
`Robert Dunham Short, III, Leesburg,
`VA (US); Edmund Colby Munger,
`CI-Ownsvfllea MD (US); Michael
`Williamson, South
`
`(56)
`
`References Cited
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`(Continued)
`FOREIGN PATENT DOCUMENTS
`
`( * ) Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`
`DE
`
`199 24 575
`
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`
`U.S.C. 154(b) by 646 days.
`
`(Continued)
`OTHER PUBLICATIONS
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`.
`(22) Filed:
`
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`
`(65)
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`
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`Apr. 26, 2000, now abandoned, which is a continua—
`tion-in-part of application No. 09/504,783, filed on
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`
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`
`Int, Cl,
`(2006.01)
`G06F 15/173
`U.S. Cl.
`.................................................... .. 709/226
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`
`(Continued)
`P .
`E
`.
`Kri
`L.
`rzmary xammer— sna
`1m
`(74) Attorney, Agent, or Firm—McDermott Will & Emery,
`LLP
`
`(57)
`
`ABSTRACT
`.
`.
`.
`“four: iomaml nélme Sew1?’ for a Czmputer network 15
`‘S°k°Se
`that mtg“ lest a POE“ °d°““‘:1°‘e F0 a °°mP(‘11“:r1§‘e“
`Zlifngcifié 50;: ‘;::.§::1:111?::i.:1a:;:
`portal authenticates apquery for a secure cgomputgr network
`address, and the domain name database stores secure com-
`puter network addresses for the computer network. Each
`secure computer network address is based on a non-standard
`P
`g
`to -level domain name, such as .scom,
`.sor ,
`.snet,
`.snet,
`.sedu, .smil and .sint.
`
`g
`60 Claims, 40 Drawin Sheets
`
`11> ROUTER
`
`E
`
`E
`
`
`IP ROUTER
`
`
`
` IP ROUTER
`
`fl
`
`
`IF ROUTER
`
`DESTINATION
`TERMINAL
`M
`
`A I
`
`P ROUTER
`
`MICROSOFT 1001
`
`1
`
`MICROSOFT 1001
`
`

`
`U.S. PATENT DOCUMENTS
`
`>D>>>>>>>>D>>>D>>D>>>>D>>>D>D>D>D>D>>D>D>D>D>D>D>D>D>>D>D>D>D>D>D>
`
`5,329,521
`5,341,426
`5,367,643
`5,559,883
`5,561,669
`5,588,060
`5,625,626
`5,654,695
`5,682,480
`5,689,566
`5,740,375
`5,774,660
`5,787,172
`5,790,548
`5,796,942
`5,805,801
`5,842,040
`5,845,091
`5,867,650
`5,870,610
`5,878,231
`5,892,903
`5,898,830
`5,905,859
`5,918,019
`5,996,016
`6,006,259
`6,006,272
`6,016,318
`6,016,512
`6,041,342
`6,052,788
`6,055,574
`6,061,736
`6,079,020
`6,092,200
`6,101,182
`6,119,171
`6,119,234
`6,147,976
`6,157,957
`6,158,011
`6,168,409
`6,175,867
`6,178,409
`6,178,505
`6,179,102
`6,222,842
`6,226,751
`6,233,618
`6,243,360
`6,243,749
`6,243,754
`6,256,671
`6,263,445
`6,286,047
`6,301,223
`6,308,274
`6,311,207
`6,324,161
`6,330,562
`6,332,158
`6,353,614
`6,425,003
`6,430,155
`6,430,610
`6,487,598
`6,502,135
`6,505,232
`6,510,154
`6,549,516
`
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`US 7,418,504 B2
`Page 2
`
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`)rovino .................... .. 709/227
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`GB
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`WO
`W0
`W0
`W0
`W0
`W0
`W0
`W0
`W0
`
`199 24 575 A1
`0 814 589
`0 814 589 A
`0 838 930
`0 838 930 A
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`
`

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`
`3
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 1 of 40
`
`US 7,418,504 B2
`
`
`
`ORIGINATING
`TERMINAL
`100
`
`
`
`IP PACKET
`
`IP ROUTER
`
`31
`
`IP ROUTER
`22.
`
`IP ROUTER
`
`E
`
`IP ROUTER
`E
`
`IP ROUTER
`A
`
`
`
`IP ROUTER
`.3;
`
`IP ROUTER
`2_8
`
`IP ROUTER
`19-
`
`up RouTER
`A
`
`INTERNET
`1_0_7
`
`
`
`
`
`
`
`
`IP ROUTER
`2_7
`
`IP ROUTER
`
`E
`
`
`
`
` DESTINATION
`48 ENCRYPTION KEY
`TERMINAL
`
`M
`
`FIG. 1
`
`4
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 2 of 40
`
`US 7,418,504 B2
`
`
`
` TARP
`TERMINAL
`
`M
`
`
`
`TARP PACKET
`
`IP ROUTER
`M
`
`
`
`
`TARP
`ROUTER
`
`
`
`3 LINK KEY
`
`,.,;EY RRRER
`
`'
`—
`E
`ROUTER
`1.31
`
`
`
`
`TARP
`
`TERMINAL
`
`M
`
`
`
`TARP PACKET
`
`140
`
`LINK
`KEY
`
`FIG. 2
`
`
`ROUTER
`'PR$3%TER
`
`ROUTER
`E
`
`IPROUTER
`TARP
`|pROUTER
`
`
`
`124
`
`IP ROUTER
`
`_
`
`
`
`E
`
`LINK
`
`5
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 3 of 40
`
`US 7,418,504 B2
`
`2°73
`
`207b
`
`207c
`
`207d
`
`° ° °
`
`
`|]i|li|1i-
`
`4\ 330 SESSION-KEY-ENCRYPTED
`PAYLOAD DATA
`
`‘\ 340 TARP PACKET WITH
`ENCRYPTED PAYLOADS
`
`‘\350 LINK-KEY-ENCRYPTED
`TARP PACKETS
`
`"
`
`'7':
`
`‘\3eo IP PACKETS WI
`ENCRYPTED TARP
`PACKETS AS PAYLOAD
`
`TARP
`DESTINATION
`
`
`
`
`
`
`
`6
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 4 of 40
`
`US 7,418,504 B2
`
`207b
`207a
`A‘
`I]i—fl-I13-‘-2 ‘ ° '
`
`207d
`
`- - 0
`
`/300 DATA STREAM
`
`207c
`
`
`
`'
`
`
`
`‘\520BLOCK-ENCRYPTED
`(SESSION-KEY) PAYLOAD
`SEQUENCE
`‘\522 ENCRYPTED BLOCK
`DIVIDED INTO PAYLOADS
`
`'3
`
` "A
`
`- 3' ‘\523 ENCRYPTED BLOCK
`D|V|DED INTO PAYLOADS
`INTERLEAVED
`
`"::“‘.‘:"*'3" ‘\523 ENCRYPTED BLOCK
`DIVIDED mm PAYLOADS
`INTERLEAVED
`
` 3' ‘\34o TARP PACKETS WITH
`ENCRYPTED PAYLOADS
`
`7
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 5 of 40
`
`US 7,418,504 B2
`
`
`
` TARP TRANSCEIVER
`
`
`ONE ALTERNATIVE T0
`COMHNE
`TARP PROCESSING
`WITH O/S IP
`PROCESSOR
`
`NETWORK (IP) LAYER
`M
`
`A
`
`III
`
`
`
` M
`
`OTHERALTERNATIVE
`TO COMBINE
`TARP PROCESSING
`WITH D.L. PROCESSOR
`(e.g., BURN INTO BOARD
`
`TARP LAYER
`fl
`
`DATA LINK LAYER
`fl
`
`FIG. 4
`
`PROM)
`
`DATA LINK
`PROTOCOL WRAPPER
`
`8
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 6 of 40
`
`US 7,418,504 B2
`
`S0
`
`S2
`
`93
`
`
`
`BACKGROUND LOOP - DECOY
`GENERATION
`
`AUTHENTICATE TARP
`PACKET
`
`
`
`OUTER LAYER DECRYPTION
`or TARP PACKET USING
`LINK KEY
`
`DUMP DECOY
`
`
`
`
`
`
`
`CHECK FOR DECOY AND
`INCREMENT PERISHABLE
`
`DECOY COUNTER AS
`
`APPROPRIATE
`
`TRANSMIT DECOY?
`
`S5
`
`YES
`
`NO
`
`DECREMENT
`TTL TTL > 0?
`
`YES
`
`DETERMINE DESTINATION
`TARP ADDRESS AND STORE
`LINK KEY AND IP ADDRESS
`
`GENERATE NEXT-HOP TARP
`ADDRESS AND STORE LINK
`KEY AND IF ADDRESS
`
`38
`
`GENERATE NEXT-HOP TARP
`ADDRESSAND STORE LINK
`KEYANDIPADDRESS
`
`GENERATE IP HEADER
`AND TRANSMIT
`
`FIG. 5
`
`310
`
`S11
`
`9
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 7 of 40
`
`US 7,418,504 B2
`
`BACKGROUND LOOP - DECOY
`GENERATION
`
`GROUP RECEIVED IP PACKETS
`INTO INTERLEAVE WINDOW
`
`DETERMINE DESTINATION TARP
`ADDRESS, INITIALIZE TTL, STORE
`IN TARP HEADER
`
`RECORD WINDOW SEQ. NOS. AND
`INTERLEAVE SEQ. NOS. IN TARP
`HEADERS
`
`CHOOSE FIRST HOP TARP
`ROUTER, LOOK UP IPADDRESS
`AND STORE IN CLEAR IP HEADER,
`OUTER LAYER ENCRYPT
`
`INSTALL CLEAR IP HEADER AND
`TRANSMIT
`
`FIG. 6
`
`10
`
`10
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 8 of 40
`
`US 7,418,504 B2
`
`DIVIDE BLOCK INTO PACKETS
`usme wmoow SEQUENCE
`DATA, ADD CLEAR IP HEADERS
`GENERATED FROM TARP
`HEADERS"
`
`S49
`
`HAND COMPLETED IP PACKETS
`TO IP LAYER PROCESS
`
`350
`
`BACKGROUND LOOP - DECOY
`GENERATION
`
`AUTHENTICATE TARP PACKET
`RECEIVED
`
`DECRYPT OUTER LAYER
`ENCRYPTION WITH LINK KEY
`
`INCREMENT PERISHABLE
`COUNTER IF DECOY
`
`THROW AWAY DECOY OR KEEP
`IN RESPONSE TO ALGORITHM
`
`CACHE TARP PACKETS UNTIL
`WINDOW IS ASSEMBLED
`
`DEINTERLEAVE PACKETS
`FORMING WINDOW
`
`DECRYPT BLOCK
`
`S48
`
`FIG. 7
`
`11
`
`11
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 9 of 40
`
`US 7,418,504 B2
`
`TEC}%\EM\L
`301
`
`SSYN
`
`PA§;2K1ET
`
`SSYN ACK
`
`PACKET
`822
`
`SSYN ACK
`
`ACK PACKET
`823
`
`
`
`825
`SECURE SESSION
`INITIATION ACK
`
`824
`SECURE SESSION
`INITIATION
`
`FIG. 8
`
`12
`
`12
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 10 of 40
`
`US 7,418,504 B2
`
`CLIENT 1 /j\ TARP
`
`ROUTER
`
`TRANSMIT TABLE
`RECEIVE TABLE
`921
`924
`?\.____j 292
`
`131.218.204.98
`131.218.204.221
`131.218.204.139
`131.218.204.12
`
`0
`0
`0
`0
`
`131.218.204.65
`131.218.204.97
`131.218.204.186
`131.218.204.55
`
`131.218.204.98
`131.218.204.221
`131.218.204.139
`131.218.204.12
`
`0
`0
`0
`0
`
`131.218.204.65
`131.218.204.97
`131.218.204.186
`131.218.204.55
`
`RECEIVE TABLE
`TRANSM|T TABLE
`922
`923
`:___;j_ _g:_____
`
`131.218.204.161
`131.218.204.66
`131.218.204.201
`131.218.204.119
`
`0
`0
`0
`0
`
`131.218.204.89
`131.218.204.212
`131.218.204.127
`131.218.204.49
`
`131.218.204.161
`131.218.204.66
`131.218.204.201
`131.218.204.119
`
`0
`0
`0
`0
`
`131.218.204.89
`131.218.204.212
`131.218.204.127
`131.218.204.49
`
`13
`
`13
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 11 of 40
`
`US 7,418,504 B2
`
`FIG. 10
`
`14
`
`14
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 12 of 40
`
`US 7,418,504 B2
`
` ._.mv_o<n_n__8”m$%22,:.532Hmm§<
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`
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`
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`
`
`
`222:2520::
`
`15
`
`15
`
`
`
`
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 13 of 40
`
`US 7,418,504 B2
`
`aiafi
`
`Hflfifi
`
`Efifi
`
`16
`
`16
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 14 of 40
`
`US 7,418,504 B2
`
`
`
`
`MODE
`OR
`
`HARDWARE
`
`
`
`
`
`
`1. PROMISCUOUS
`
`SAME FOR ALL NODES
`
`OR (F3{(mB|bEhgELY
`
`IP ADDRESSES
`
`DISCRIMINATOR FIELD
`
`CAIIWBEWIED
`
`CAIINBEIIQNED
`
`CAN BE VARIED
`IN SYNC
`
`CAN BE VARIED
`IN SYNC
`
`
`
`
`
`
`
`2. PROMISCUOUS
`PER VPN
`
`
`
`FIXED FOR EACH VPN
`
`
`
`CAN BE VARIED
`IN SYNC
`
`3. HARDWARE
`HOPPING
`
`CAN BE VARIED
`IN SYNC
`
`CAN BE VARIED
`IN SYNC
`
`FIG. 12B
`
`17
`
`17
`
`

`
`U
`
`S_32
`
`anF
`
`S2
`
`tnmaP
`
`UA
`
`M
`
`W
`
`US 7,418,504 B2
`
`mEd
`
`360%mm;M:2
`
`:55
`
`9.5%
`
`Q2“.
`
`oz
`
`3%$228
`
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`
`22
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`
`32
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`
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`
`18
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`82
`
`18
`
`
`
`
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 16 of 40
`
`US 7,418,504 B2
`
`CURRENT IP PAIR ~+~~-
`
`ckpLo ‘
`ckpt_n ‘
`ckpt_r
`
`TRANSMITTER
`
`IP PAIR 1
`
`IP PAIR 2
`
`SENDER'S ISP
`
`|P PAIR1
`
`IP PA|R2
`0
`'
`
`CURRENT IP PAIR
`
`ckpt_o
`ckpt_n
`t_I'
`
`TRANSMITTER
`
`RECIPIENT'S ISP
`
`KEPT IN SYNC FOR SENDER T0 RECIPIENT SYNCHRONIZER 4 --------------------- -->
`
`KEPT IN SYNC FOR RECIPIENT T0 SENDER SYNCHRONIZERT»
`
`FIG. 14
`
`19
`
`19
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 17 of 40
`
`US 7,418,504 B2
`
`@
`
`SYNC_REQ
`
`@ WHEN SYNCHRDNIZATION
`BEGINS TRANSMIT (RETRANSMIT
`PERIODICALLY UNTIL ACKed)
`SYNC_REQ USING NEW
`TRANSMITTER CHECKPOINT IP
`PAIR ckpt_n AND GENERATE
`NEW RECEIVER RESPONSE
`
`CHECKPOINT ckpI_r
`
`# WHEN SYNC_ACK
`ARRIVES WITH INCOMING
`HEADER = ckpt_r:
`GENERATE NEW
`CHECKPOINT IP PAIR
`ckpt_n IN TRANSMITTER
`
`]w
`
`* WHEN SYNC_REQ ARRIVES
`WITH INCOMING HEADER =
`
`II
`
`RECEIVER'S ckpI_n:
`°UPDATE WINDOW
`-GENERATE NEW
`CHECKPOINT IP PAIR
`ckpt_n IN RECEIVER
`-GENERATE NEW
`CHECKPOINT IP PAIR
`ckpt_r IN TRANSMITTER
`°TRANSMIT SYNC_ACK
`USING NEW CHECKPOINT
`IP PAIR ckpt_r
`
`FIG. 15
`
`20
`
`20
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 18 of 40
`
`US 7,418,504 B2
`
`21
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 19 of 40
`
`US 7,418,504 B2
`
`000 —
`
`VIIIIIIIIIII
`
`
`
`
`
`VIIIIIIIIIIIA
`VIIIIIIIIIIIA
`TIIIIIIIIIIA.
`WIIIIIIIIIIA
`WIIIIIIIIIIA
`O
`
`O
`
`W|NDOW_SlZE
`
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`
`
`
`
`
`
`W'”°°W-3'25 VIIIIIIIIIIIA
`VIIIIIIIIIIJ
`VIIIIIIIIIIIA
`
`
`VIIIIIIIIIIIA
`
`FIG. 17
`
`22
`
`22
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 20 of 40
`
`US 7,418,504 B2
`
`—V
`
`IIIIIIIIIIA
`
`WIIIIIIIIIIA
`VIIIIIIIIIIIA
`WIIIIIIIIIIA
`WIIIIIIIIIIA
`WIIIIIIIIIII
`
`000
`
`W|NDOW_S|ZE
`
`W|NDOW_SlZE
`
`0
`
`23
`
`23
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 21 of 40
`
`US 7,418,504 B2
`
`|NACT|VE
`
`ACTIVE
`
`USED
`
`H E
`
`WIIIIIIIIIIA
`C
`
`000
`
`W|NDOW_S|ZE
`
`W|NDOW_S|ZE
`
`VIIIIIIIIIIA
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`Vlllllllllll.
`
`O
`
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`WIIIIIIIIIIA,
`
`555555555555
`
`
`
`111111111114
`
`FIG. 19
`
`24
`
`24
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 22 of 40
`
`US 7,418,504 B2
`
`
` COMPUTER #2
`
`
`
`
` COMPUTER #1
`
`25
`
`25
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 23 of 40
`
`US 7,418,504 B2
`
`2101
`
`2102
`
`2103
`
`2104
`
`2105
`
`2106
`
`2107
`
`2108
`
`2109
`
`AD TABLE
`
`
`AE TABLE
`
`AF TABLE
`
`}
`
`BDTABLE
`
`BE TABLE
`
`
`
`DZ
`
`BF TABLE
`
`
`
`LINK DOWN
`
`26
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 24 of 40
`
`US 7,418,504 B2
`
`
`
` MORE THAN
`
`ONE TRANSMITTER
`TURNED ON?
`
`
`
`PATH X
`
`QUALITY < THRESHOLD?
`
`N0
`
`SET WEIGHT
`TO MIN. VALUE
`
`
`
`
`
`PATH X
` DECREASE WEIGHT
`WEIGHT LESS THAN
`FOR PATH X
`STEADY STATE
` 2208
`VALUE?
`
`
`
`INCREASE
`WEIGHT FOR PATH X
`TOWARD STEADY
`STATE VALUE
`
`
`
`ADJUST WEIGHTS
`FOR REMAINING
`PATHS SO THAT
`WEIGHTS EQUAL ONE
`
`FIG. 22A
`
`27
`
`27
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 25 of 40
`
`US 7,418,504 B2
`
`(EVENT) TRANSMITTER
`FOR PATH x
`TURNS OFF
`
`
`
`
`2210
`
`DROP ALL PACKETS
`UNTIL ATRANSMITTER
`TURNS 0N
`
`
`
`
`
`AT LEAST
`ONE TRANSMITTER
`TURNED ON?
`
`
`
`
`
`SET WEIGHT
`TO ZERO
`
`ADJUST WEIGHTS
`FOR REMAINING PATHS
`
`SO THAT WEIGHTS
`EQUAL ONE
`
`FIG. 22B
`
`28
`
`28
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 26 of 40
`
`US 7,418,504 B2
`
`
`
`2302
`
`PATH x1
`
`PATH X2
`
`
`
`2308
`
`TRANSMIT TABLE
`3
`D
`EE'='
`———
`
`
`
`PACKET
`
`TRANSMITTER
`
`PATH X4
`
`
`
`Zfj
`
`2301
`
`
`
`w (X1) = 0.2
`
`w (x2) = 0.1
`
`w (x3) = 0.6
`
`w (x4) = 0.1
`
`
`
`
`
`LINK QUALITY
`MEASUREMENT
`FUNCTION
`
`FIG. 23
`
`29
`
`29
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 27 of 40
`
`US 7,418,504 B2
`
`2403
`
`2404
`
`
`9 100Mbls MESST=32 9
`
`
`
`
`COMPUTER
`
`
`
`
`COMPUTER
`
`9 25Mb/s MESS T =8
`
`FIG. 24
`
`30
`
`30
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 28 of 40
`
`US 7,418,504 B2
`
`2502
`
`
`
`DNS RESP
`
`PAGE REQ
`
`
`
`PAGE RESP
`
`
`
`FIG. 25
`(PRIOR ART)
`
`2501
`
`2504
`
`0 WEB
`BROWSER
`
`
`
`31
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 29 of 40
`
`US 7,418,504 B2
`
` DNS
`SERVER
`
`2602
`
`
`
`
`
`WEB
`BROWSER
`
`
`
`GATE KEEPER
`
`-HOPPING —ULES
`
`
`
`UNSECURE
`TARGET
`SITE
`
`2611
`
`FIG. 26
`
`32
`
`32
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 30 of 40
`
`US 7,418,504 B2
`
`
`
` RECEIVE
`DNS REQUEST
`FOR TARGET SITE
`
` ACCESS TO
`
`SECURE SITE
`REQUESTED?
`
`
`
`
`
`USER
`AUTHORIZED TO
`CONNECT?
`
`RETURN
`"HOST UNKNOWN"
`ERROR
`
`FIG. 27
`
`33
`
`2701
`
`2706
`
`33
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 31 of 40
`
`US 7,418,504 B2
`
`2803
`
`HOST
`
`EDGE
`ROUTER
`
` 2801
`COMPUTER #1
`
`2804
`
`
`
`HOST
`COMPUTER #2
`
`FIG. 28
`
`34
`
`34
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 32 of 40
`
`US 7,418,504 B2
`
` HOSTCOMPUTER#1
`
`EDGE
`ROUTER
`
`
`
`HOSTCOMPUTER#2
`
` TX
`
`RX
`
`2902
`
`2903
`
`FIG. 29
`
`35
`
`35
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 33 of 40
`
`US 7,418,504 B2
`
`$:_zwzs:
`
`w>_§m
`
`352$
`
`3%
`
`om.®_u_
`
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`
`36
`
`36
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 34 of 40
`
`US 7,418,504 B2
`
`3103
`
`CLIENT #2
`
`HACKER
`
`
`
`TXIRX
`
`TX/RX
`
`TXIRX
`
`
`
`3102
`
`3105
`
`FIG. 31
`
`37
`
`37
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 35 of 40
`
`US 7,418,504 B2
`
`CLIENT
`
`SERVER
`
`PASS DATA UP STACK
`ckpI_o=ckpI_n
`GENERATE NEW ckpt_n
`GENERATE NEW ckpI_r FOR
`TRANSMITTER SIDE
`TRANSMIT SYNC_ACK
`CONTAINING ckpt_o
`
`ckpt_o=ckpI_n
`GENERATE NEW ckpI_n
`GENERATE NEW ckpI_r FOR
`TRANSMITTER SIDE
`
`TRANSMIT SYNC_ACK
`CONTAINING ckpt_o
`
`SEND DATA PACKET
`
`USING ckpI_n
`CKPT_0=ckpI_n
`GENERATE NEW ckpI_n
`ETFART TIMER, SHUTTRANSMITTER
`
`IF CKPT_O IN SYNC_ACK
`MATCHES TRANSMITTER'S
`
`ckpt_o
`UPDATE RECEIVER‘S
`ckpI_r
`KILLTIMER, TURN
`TRANSMITTER ON
`
`SEND DATA PACKET
`USING ckpt_n
`ckpt_o=ckpt_n
`GENERATE NEW ckpI_n
`START TIMER, SHUT TRANSMITTER
`OFF
`
`WHEN TIMER EXPIRES
`TRANSMIT SYNC_REQ
`USING TRANSMITTERS
`
`ckpt_o, START TIMER
`
`IF ckpt_o IN SYNC_ACK
`MATCHES TRANSMITTER'S
`
`ckpt_o
`UPDATE RECEIVER'S
`
`ckpI_r
`KILL TIMER, TURN
`TRANSMITTER ON
`
`SYNC‘REQ
`
`FIG. 32
`
`38
`
`38
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 36 of 40
`
`US 7,418,504 B2
`
`
`
`
`
`mzoems_ooE.<_._o.__<s_.m_:9:$.me_E5
`
`28:82828E8
`
`%
`
`gm8.0_u_
`
`>Es_8m.
`
`IL«N8
`
`:8
`
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`
`wsam
`
`Ema;
`
`8%
`
`$8
`
`mzoemQ
`
`:2
`
`28
`
`%mz§z_
`
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`
`fimgog
`
`wsaw8
`
`z_.2E
`
`3%
`
`39
`
`39
`
`
`
`
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 37 of 40
`
`US 7,418,504 B2
`
`3400
`
`LAUNCH LINK TO
`.COM SITE
`
`3404
`
`3401
`
`DISPLAY WEB PAGE
`CONTAINING GO
`SECURE HYPERLINK
`
` E
`
`3405
`
`3406
`
`
`
`DOWNLOAD AND
`INSTALL PLUG-IN
`
`CLOSE CONNECTION
`
`AUTOMATIC REPLACEMENT OF TOP-LEVEL
`DOMAIN NAME W|TH SECURE TOP-LEVEL
`DOMAIN NAME
`
`3407
`
`3412
`
`D|SPLAY"SECURE" ICON
`
`ACCESS SECURE PORTALAND
`
`SECURE NETWORKAND SECURE DNS
`
`3403
`
`OBTAIN SECURE COMPUTER NETWORK
`
`
`
`
`CCNNECTIDN
`
`'
`YES
`
`3413
`
`N0
`
`ACCESS GATE KEEPER AND RECEIVE
`PARAMETERS FOR ESTABLISHING VPN
`WE“ SECURE WEBSEE
`
`CONNECT To SECURE WEBSITE
`USING vPN BASED oN PARAMETERS
`ESTABLISHED BY GATE KEEPER
`
`3410
`
`3411
`
`3414
`
`DOMAIN NAME WITH NON-SECURE
`TOP-LEVEL DDMAIN NAME
`
`3415
`
`DISPLAY “G0 SECURE“ HYPERLINK
`
`E1
`
`FIG. 34
`
`40
`
`40
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 38 of 40
`
`US 7,418,504 B2
`
`
`
`REQUESTOR ACCESSES WEBSITE
`AND LOGS INTO SECURE
`DOMAIN NAME REGISTRY SERVICE
`
`3501
`
`REQUESTER COMPLETES ONLINE
`REGISTRATION FORM
`
`QUERY STANDARD DOMAIN NAME
`SERVICE REGARDING OWNERSHIP
`OF EQUIVALENT NON-SECURE
`DOMAIN NAME
`
`RECEIVE REPLY FROM STANDARD
`DOMAIN NAME REGISTRY
`
`
`
`
`INFORM REQUESTOR
`OF CONFLICT
`
`3506
`
`
`
`3505
`
`N0
`
`VERIFYINFORMATION AND
`ENTER PAYMENTINFORMATION
`
`3507
`
`REGISTER SECURE DOMAIN NAME
`
`
`
`3508
`
`FIG. 35
`
`
`
`41
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 39 of 40
`
`US 7,418,504 B2
`
` 3611
` 3610
`
`WEB SERVER
`
`SERVER PROXY
`
`VPN GUARD
`
`
`
`COMPUTER NETWORK
`
`3602
`
`FIREWALL
`
`3601
`
`3600
`
`3606
`
`3605
`
`
`
`| BROWSER I PROXYAPPLICATION I
`
`3607
`
`CLIENT COMPUTER
`
`3604
`
`FIG. 36
`
`42
`
`42
`
`

`
`U.S. Patent
`
`Aug. 26, 2008
`
`Sheet 40 of 40
`
`US 7,418,504 B2
`
`GENERATE MESSAGE PACKETS
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`3701
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`cox:c:O
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`/
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`MODIFY MESSAGE PACKETS WITH PRIVATE
`CONNECTION DATA AT AN APPLICATION LAYER
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`3702
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`SEND TO HOST COMPUTER
`THROUGH FIREWALL
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`RECEIVE PACKETS AND AUTHENTICATE
`AT KERNEL LAYER OF HOST COMPUTER
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`RESPOND TO RECEIVED MESSAGE
`PACKETS AND GENERATE REPLY
`MESSAGE PACKETS
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`MODIFY REPLY MESSAGE PACKETS WITH
`PRIVATE CONNECTION DATA AT A
`KERNEL LAYER
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`SEND PACKETS TO CLIENT COMPUTER
`THROUGH FIREWIRE
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`RECEIVE PACKETS AT CLIENT
`COMPUTER AND AUTHENTICATE AT
`APPLICATION LAYER
`
`FIG. 37
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`43
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`3703
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`3704
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`3705
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`3706
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`3707
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`3708
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`43
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`

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`US 7,418,504 B2
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`1
`AGILE NETWORK PROTOCOL FOR SECURE
`COMMUNICATIONS USING SECURE
`DOMAIN NAMES
`
`CROSS-REFERENCE TO RELATED
`APPLICATIONS
`
`This application claims priority from and is a continuation
`patent application of U.S. application Ser. No. 09/558,210,
`filed Apr. 26, 2000 now abandoneed, which is a continuation-
`in-part patent application ofpreviously-filed U.S. application
`Ser. No. 09/504,783, filed on Feb. 15, 2000, now U.S. Pat. No.
`6,502,135, issued Dec. 31, 2002, which claims priority from
`and is a continuation-in-part patent application ofpreviously-
`filed U.S. application Ser. No. 09/429,643, filed on Oct. 29,
`1999 now U.S. Pat. No. 7,010,604. The subject matter ofU.S.
`application Ser. No. 09/429,643, which is bodily incorporated
`herein, derives from provisional U.S. application Nos.
`60/106,261 (filed Oct. 30, 1998) and 60/137,704 (filed Jun. 7,
`1999). The present application is also related to U.S. appli-
`cation Ser. No. 09/558,209, filed Apr. 26, 2000, and which is
`incorporated by reference herein.
`
`GOVERNMENT CONTRACT RIGHTS
`
`This invention was made with Government support under
`Contract No. 360000-1999-000000-QC-000-000 awarded by
`the Central Intelligence Agency. The Government has certain
`rights in the invention.
`
`BACKGROUND OF THE INVENTION
`
`A tremendous variety of methods have been proposed and
`implemented to provide security and anonymity for commu-
`nications over the Internet. The variety stems, in part, from the
`different needs of different Internet users. A basic heuristic
`
`framework to aid in discussing these different security tech-
`niques is illustrated in FIG. 1. Two terminals, an originating
`terminal 100 and a destination terminal 110 are in communi-
`cation over the Internet. It is desired for the communications
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`to be secure, that is, immune to eavesdropping. For example,
`terminal 100 may transmit secret information to terminal 110
`over the Internet 107. Also, it may be desired to prevent an
`eavesdropper from discovering that terminal 100 is in com-
`munication with terminal 1 10. For example, ifterminal 1 00 is
`a user and terminal 110 hosts a web site, terminal 100’s user
`may not want anyone in the intervening networks to know
`what web sites he is “visiting.” Anonymity would thus be an
`issue, for example, for companies that want to keep their
`market research interests private and thus would prefer to
`prevent outsiders from knowing which web-sites or other
`Internet resources they are “visiting.” These two security
`issues may be called data security and anonymity, respec-
`tively.
`Data security is usually tackled using some form of data
`encryption. An encryption key 48 is known at both the origi-
`nating and terminating terminals 100 and 110. The keys may
`be private and public at the originating and destination termi-
`nals 100 and 110, respectively or they may be symmetrical
`keys (the same key is used by both parties to encrypt and
`decrypt). Many encryption methods are known and usable in
`this context.
`To hide trafiic from a local administrator or ISP, a user can
`employ a local proxy server in communicating over an
`encrypted channel with an outside proxy such that the local
`administrator or ISP only sees the encrypted trafiic. Proxy
`servers prevent destination servers from determining the
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`identities of the originating clients. This system employs an
`intermediate server interposed between client and destination
`server. The destination server sees only the Internet Protocol
`(IP) address ofthe proxy server and not the originating client.
`The target server only sees the address of the outside proxy.
`This scheme relies on a trusted outside proxy server. Also,
`proxy schemes are vulnerable to trafiic analysis methods of
`determining identities of transmitters and receivers. Another
`important limitation of proxy servers is that the server knows
`the identities of both calling and called parties. In many
`instances, an originating terminal, such as terminal A, would
`prefer to keep its identity concealed from the proxy, for
`example, ifthe proxy server is provided by an Internet service
`provider (ISP).
`To defeat traffic analysis, a scheme called Chaum’s mixes
`employs a proxy server that transmits and receives fixed
`length messages, including dummy messages. Multiple origi-
`nating terminals are connected through a mix (a server) to
`multiple target servers. It is difficult to tell which of the
`originating terminals are communicating to which ofthe con-
`nected target servers, and the dummy messages confuse
`eavesdroppers’ efforts to detect communicating pairs by ana-
`lyzing traffic. A drawback is that there is a risk that the mix
`server could be compromised. One way to deal with this risk
`is to spread the trust among multiple mixes. If one mix is
`compromised, the identities of the originating and target ter-
`minals may remain concealed. This strategy requires a num-
`ber of alternative mixes so that the intermediate servers inter-
`
`posed between the originating and target terminals are not
`determinable except by compromising more than one mix.
`The strategy wraps the message with multiple layers of
`encrypted addresses. The first mix in a sequence can decrypt
`only the outer layer of the message to reveal the next desti-
`nation mix in sequence. The second mix can decrypt the
`message to reveal the next mix and so on. The target server
`receives the message and, optionally, a multi-layer encrypted
`payload containing return information to send data back in
`the same fashion. The only way to defeat such a mix scheme
`is to collude among mixes. If the packets are all fixed-length
`and intermixed with dummy packets, there is no way to do
`any kind of trafiic analysis.
`Still another anonymity technique, called ‘crowds,’ pro-
`tects the identity of the originating terminal froin the inter-
`mediate proxies by providing that originating terminals
`belong to groups ofproxies called crowds. The crowd proxies
`are interposed between originating and target terminals. Each
`proxy through which the message is sent is randomly chosen
`by an up stream proxy. Each intermediate proxy can send the
`message either to another randomly chosen proxy in the
`“crowd” or to the destination. Thus, even crowd members
`carmot determine if a preceding proxy is the originator of the
`message or if it was simply passed fror11 another proxy.
`ZKS (Zero-Knowledge Systems) Anonymous IP Protocol
`allows users to select up to any of five different pseudonyms,
`while desktop software encrypts outgoing trafiic and wraps it
`in User Datagrarn Protocol (UDP) packets. The first server in
`a 2+-hop system gets the UDP packets, strips off one layer of
`encryption to add another, then sends the traffic to the next
`server, which strips off yet another layer of encryption and
`adds a new one. The user is permitted to control the number of
`hops. At the final server, trafiic is decrypted with an untrace-
`able IP address. The technique is called onion-routing. This
`method can be defeated using trafiic analysis. For a simple
`example, bursts of packets from a user during low-duty peri-
`ods can reveal the identities of sender and receiver.
`
`Firewalls attempt to protect LANs from unauthorized
`access and hostile exploitation or damage to computers con-
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`US 7,418,504 B2
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`3
`nected to the LAN. Firewalls provide a server through which
`all access to the LAN must pass. Firewalls are centralized
`systems that require administrative overhead to maintain.
`They can be compromised by virtual-machine applications
`(“applets”). They instill a false sense of security that leads to
`security breaches for example by users sending sensitive
`information to servers outside the firewall or encouraging use
`of modems to sidestep the firewall security. Firewalls are not
`useful for distributed systems such as business travelers,
`extranets, small teams, etc.
`
`SUMMARY OF THE INVENTION
`
`A secure mechanism for communicating over the intemet,
`including a protocol referred to as the Tum1eledAgile Routing
`Protocol (TARP), uses a unique two-layer encryption format
`and special TARP routers. TARP routers are similar in func-
`tion to regular IP routers. Each TARP router has one or more
`IP addresses and uses normal IP protocol to send IP packet
`messages
`(“packets” or “datagrams”). The IP packets
`exchanged between TARP terminals via TARP routers are
`actually encrypted packets whose true destination address is
`concealed except to TARP routers and servers. The normal or
`“clear” or “outside” IP header at