`New Bay Capital v. Virnetx
`Case IPR2013-00375
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`Page 2
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`............ .. 709/225
`
`
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`
`
`6,502,135 131* 12/2002 Mungeretal.
`
`
`
`
`
`6505 232 B1
`1/2003 Mi
`doll etal.
`
`
`
`6:510:154 B1
`1/2003 Magyiiasetal.
`
`
`
`
`6,549,516 B1
`4/2003 Albefi et 31.
`
`
`
`
`
`6,557,037 B1
`4/2003 Provino
`
`
`
`
`6,571,296 B1
`5/2003 Dillon
`
`
`
`
`6,571,338 B1
`5/2003 Shaio etal.
`
`
`
`
`
`6,581,166 B1
`6/2003 Hirstetal.
`
`
`
`
`............. .. 713/201
`6,606,708 131*
`8/2003 Devine etal.
`
`
`
`
`
`6,618,761 B2
`9/2003 Mungeretal.
`
`
`
`
`6,671,702 B2
`12/2003 Kruglikov etal.
`
`
`
`
`6,687,551 B2
`2/2004 Steindl
`
`
`
`
`6,714,970 B1
`3/2004 Fiveash etal.
`
`
`
`
`6,717,949 B1
`4/2004 Boden et 31.
`
`
`
`
`
`6,751,738 132*
`6/2004 Wesingeretal.
`
`
`6,760,766 B1
`7/2004 Sahlqvist
`
`
`
`
`6,826,616 B2
`11/2004 Larson etal.
`
`
`
`
`
`6,839,759 B2
`1/2005 Larson et al.
`
`
`
`
`
`7,010,604 B1
`3/2006 Mungeretal.
`
`
`
`7,133,930 B2
`11/2006 Munger et al.
`
`
`
`
`7,188,180 B2
`3/2007 Larson etal.
`
`
`
`
`
`7,197,563 B2
`3/2007 Sheymov etal.
`
`
`
`
`2002/0004898 A1
`1/2002 Droge
`
`
`
`
`2003/0196122 A1* 10/2003 Wesingeretal.
`
`
`
`2005/0055306 A1
`3/2005 Milleretal.
`
`
`
`
`2006/0059337 A1*
`3/2006 Poyhonen etal.
`
`
`
`
`
`
`
`
`.......... .. 713/201
`
`
`
`
`
`
`
`
`
`.......... .. 713/201
`
`
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`......... .. 713/165
`
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`
`
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`
`
`
`
`
`
`
`
`
`
`..... .. 370/401
`
`
`
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`............ .. 726/15
`
`
`
`
`
`
`
`
`
`
`..... .. 370/352
`
`
`
`................ .. 713/201
`
`
`
`
`
`
`
`U.S. PATENT DOCUMENTS
`
`
`4,988,990 A
`1/1991 Warrior
`
`
`
`...................... .. 380/273
`5,164,986 A * 11/1992 Bright
`
`
`
`
`
`5,276,735 A
`1/1994 Boebert et al.
`
`
`
`
`5,311,593 A
`5/1994 Carrni
`
`
`
`5,329,521 A
`7/1994 Walsh etal,
`
`
`
`
`5,341,426 A
`8/1994 Barneyetal
`
`
`
`5,367,643 A
`11/1994 Chang etal,
`
`
`
`
`5,559,883 A
`9/1996 Williams
`
`
`
`5,561,669 A
`10/1996 Lenneyetal
`
`
`
`5,588,060 A
`12/1996 Aziz
`
`
`
`5,625,626 A
`4/1997 Uniekila
`
`
`
`5,654,695 A
`8/1997 Olnowich et al.
`
`
`
`
`5,682,480 A
`10/1997 Nakagawa
`
`
`
`5,689,566 A
`11/1997 Nguyen
`
`
`
`5,740,375 A
`4/1998 Dunne etal,
`
`
`
`
`5,774,660 A
`6/1998 Brendel et al.
`
`
`
`5,787,172 A
`7/1998 Arnold
`
`
`
`5,790,548 A *
`8/1998 Sistanizadeh et al.
`
`
`
`
`5,796,942 A
`8/1998 Esbensen
`
`
`
`5,805,801 A
`9/1998 Hollowayetal,
`
`
`
`5,842,040 A
`11/1998 Hnghesetal,
`
`
`
`
`5,845,091 A
`12/1998 Dunne etal,
`
`
`
`
`5,867,650 A
`2/1999 Oslerrnan
`
`
`
`5,870,610 A
`2/1999 Beyda etal,
`
`
`
`
`5,878,231 A
`3/1999 Baehr etal.
`
`
`
`
`5,892,903 A
`4/1999 Klaus
`
`
`
`5,898,830 A *
`4/1999 Wesingeretal.
`
`
`
`5,905,859 A
`5/1999 Holloway et al.
`
`
`
`
`5,918,019 A
`6/1999 Valencia
`
`
`
`5,996,016 A
`11/1999 Thalheimer etal.
`
`
`
`6,006,259 A
`12/1999 Adelman etal.
`
`
`
`
`6,006,272 A
`12/1999 Aravamudan etal.
`
`
`
`6,016,318 A
`1/2000 Tomoike
`
`
`
`6,016,512 A
`1/2000 Huitema
`
`
`
`6,041,342 A
`3/2000 Yamaguchi
`
`
`
`6,052,788 A
`4/2000 Wesinger,Jr.etal.
`
`
`
`6,055,574 A
`4/2000 Smorodinsky etal.
`
`
`
`
`6,061,736 A
`5/2000 Rochbergeretal.
`
`
`
`6,079,020 A *
`6/2000 Liu .......................... .. 713/201
`
`
`
`
`6,092,200 A
`7/2000 Muniyappa etal.
`
`
`
`
`6,101,182 A *
`8/2000 Sistanizadeh etal.
`
`
`
`
`6,119,171 A
`9/2000 Alkhatib
`
`
`
`6,119,234 A *
`9/2000 Aziz etal.
`
`
`
`
`6,147,976 A
`11/2000 Shand etal.
`
`
`
`6,157,957 A
`12/2000 Berthaud
`
`
`
`6,158,011 A
`12/2000 Chen etal.
`
`
`
`6,168,409 B1
`1/2001 Fare
`
`
`
`
`6,175,867 B1
`1/2001 Taghadoss
`
`
`
`
`6,178,409 B1
`1/2001 Weber etal.
`
`
`
`
`
`5,178,505 B1
`1/3001 Se1111e1de1e131
`
`
`
`
`
`5,179,103 B1
`1/3001 Webe1e131~
`
`
`
`
`
`5,333,843 B1
`4/3001 S35Y311 e1 31
`
`
`
`
`
`6,226,751 B1
`5/2001 Arrowet al.
`
`
`
`
`5,333,518 B1
`5/3001 S1131111011
`
`
`
`
`6,243,360 B1
`6/2001 Basilico
`
`
`
`
`5,343,749 B1
`5/3001 S113131T1311e131
`
`
`
`
`5,343,754 B1
`5/3001 G11e1111 e131
`
`
`
`
`
`6,256,671 B1 *
`7/2001 Strentzsch et al.
`
`
`
`
`
`6,263,445 B1
`7/2001 Blumenau
`
`
`
`
`5,385,047 B1
`9/3001 R31T13113111311e131
`
`
`
`
`
`
`
`
`
`
`5,301,333 B1
`10/3001 H13S131e131
`6,308,274 B1
`10/2001 Swift
`
`
`
`
`5,311,307 B1
`10/3001 M1g11d011e131
`
`
`
`
`5,334,151 B1
`11/3001 K0911
`
`
`
`
`6,330,562 B1
`12/2001 Boden etal.
`
`
`
`
`
`5,333,158 B1 * 13/3001 R151eY e131 ~~~~~~~~~~~~~~ ~- 709/319
`
`
`
`
`
`
`6,353,614 B1
`3/2002 Borella etal.
`
`
`
`
`
`5,425,003 B1 *
`7/2002 Herzog el 31 ------------- -- 709/223
`
`
`
`
`
`
`
`6,430,155 B1
`8/2002 Davie etal.
`
`
`
`
`
`6,430,610 B1
`8/2002 Carter
`
`
`
`
`6,487,598 B1
`11/2002 Valencia
`
`
`
`
`........ .. 709/227
`
`
`
`
`
`
`
`
`
`
`
`Page 2 of 62
`
`FOREIGN PATENT DOCUMENTS
`
`
`
`
`
`E1’
`
`E1’
`
`E1’
`
`E1’
`
`E1’
`
`E1’
`
`013
`
`013
`
`013
`
`013
`
`W0
`
`W0
`
`W0
`
`W0
`
`W0
`
`W0
`
`W0
`
`W0
`
`W0
`
`W0
`
`
`0 814 589
`
`
`
`0814 589 A
`
`
`0 838 930
`
`
`
`0 838930 A
`
`
`
`835305 A1
`
`
`0858189
`
`3 317 793
`
`
`
`3317 793 A
`
`
`3334181 A
`
`3334181 A
`
`9837783 A
`
`W0 98/37783
`
`
`W0 9837783 A
`
`
`W0 98 55930
`
`
`W0 98 59470
`
`
`W0 99 38081
`
`
`W0 99 48303
`
`
`W0 00/ 17775
`
`
`W0 00/70458
`
`
`W00150588
`
`
`13/ 1997
`
`13/1997
`
`4/ 1998
`
`4/ 1998
`
`4/1998
`
`8/1998
`
`4/ 1998
`
`4/ 1998
`
`8/ 1999
`
`8/1999
`
`0/ 1998
`
`0/ 1998
`
`5/ 1998
`
`13/ 1998
`
`13/1998
`
`7/ 1999
`
`9/1999
`
`3/3000
`
`11/3000
`
`7/3001
`
`
`
`
`
`
`Internet
`
`
`
`
`
`
`
`OTHER PUBLICATIONS
`
`
`Donald E. Eastlake, 3”’, “Domain Name System Security Exten-
`
`
`
`
`
`
`
`
`sions”, Internet Draft, Apr. 1998, pp. 1-51.
`
`
`
`
`
`
`
`D. B. Chapman et al., “Building Internet Firewalls”, Nov. 1995, pp.
`
`
`
`
`
`
`
`
`273.375.
`
`P. Srisuresh etal., “DNA extensions to Network address Translators
`
`
`
`
`
`
`
`(DNS_ALG)”, Internet Draft, Jul. 1998, pp. 1-27.
`
`
`
`
`
`
`
`James E. Bellaire, “New Statement of Rules—Namin
`
`
`
`
`
`g
`Domains”, Internet Newsgroup, Jul. 30, 1995, lpage.
`
`
`
`
`
`
`
`1). Clark, “Us C3115 for private D0main_Name system”, Computer
`
`
`
`
`
`
`
`
`g0ciety,Aug. 1, 1993,1515. 22-25.
`
`
`
`AugustBequai,“BalancingLegal ConcernsOVerCrimeandSecurity
`
`
`
`
`
`
`
`
`
`
`
`in Cyberspace”, Computer & Security, Vol. 17, No. 4, 1998, pp.
`293.298.
`
`Rich Winkel, “CAQ: Networking With Spooks: The NET & The
`
`
`
`
`
`
`
`
`Control Of Information”, Internet Newsgroup, Jun. 21, 1997, 4
`
`
`
`
`
`
`
`
`3 es.
`
`ISe§.rch Report (dated Jun. 18, 2002), International Application No.
`
`
`
`
`
`
`
`
`PCT/US01/13260,
`
`Search Report (dated Jun. 28, 2002), International Application No.
`
`
`
`
`
`
`
`
`PCTMS01/13261.
`
`Donald E. Eastlake, “Domain Name System Security Extensions”,
`
`
`
`
`
`
`DNS Security Working Group, Apr. 1998, 51 pages.
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`Page 2 of 62
`
`
`
`
`
`many,
`[Online] 1999, pp. 85-102, XP002399276, ISBN 3-540-
`
`
`
`
`
`
`
`
`66695-B, retrieved from the Internet: URL: http://www. springerlink.
`
`
`
`
`
`
`
`com/content/4uac0tb0hecoma89/fulltext.pdf>.
`
`Dolev, Shlomi and Ostrovsky, Rafil, Efficient Anonymous Multicast
`
`
`
`
`
`
`
`and Reception (Extended Abstract), 16 pages.
`
`
`
`
`
`
`F. Halsall, “Data Communications, Computer Networks and Open
`
`
`
`
`
`
`
`Systems”, Chapter 4, Protocol Basics, 1996, pp. 198-203.
`
`
`
`
`
`
`
`Glossary for the Linux FreeS/WAN project, printed from http://
`
`
`
`
`
`
`
`
`
`liberty.freeswan .org/freeswan_trees/freeswan-1 .3/
`doc/glo ssary.
`
`
`
`
`html on Feb. 21, 2002, 25 pages.
`
`
`
`
`
`J. Gilmore, “Swan: Securing the Internet against Wiretapping”,
`
`
`
`
`
`
`
`
`printed from http ://liberty. freeswan. org/freeswan_trees/freeswan- 1 .
`
`
`
`
`
`
`
`
`
`3.doc/rationale.html on Feb. 21, 2002, 4 pages.
`
`
`
`
`
`Linux FreeS/WAN Index File, printed from http://liberty.freewan.
`
`
`
`
`
`
`org/freeswan trees/freeswan-1.3/doc/ on Feb. 21, 2002, 3 pages.
`
`
`
`
`
`
`Reiter, Michael K. and Rubin, Aviel D. (AT&T Labs—Research),
`
`
`
`
`
`
`
`Crowds: Anonymity for Web Transactions, pp. 1-23.
`
`
`
`
`
`
`RFC 2401-Security Architecture for the Internet Protocol (RTP).
`
`
`
`
`
`
`
`RFC 2543-SIP: Session Initiation Protocol (SIP or SIPS).
`
`
`
`
`
`
`
`Rubin, Aviel D., Geer, Daniel, and Ranum, Marcus J. (Wiley Com-
`
`
`
`
`
`
`
`
`
`
`puter Publishing), “Web Security Sourcebook”, pp. 82-94.
`
`
`
`
`
`
`
`Search Report, IPER (dataed Nov. 13, 2002), International Applica-
`
`
`
`
`
`
`
`
`
`tion No. PCT/USO 1/04340.
`
`
`
`
`Search Report, IPER (dated Feb. 6, 2002), International Application
`
`
`
`
`
`
`
`No. PCT/US01/13261.
`
`
`Search Report, IPER (dated Jan. 14, 2003), International Application
`
`
`
`
`
`
`
`
`No. PCT/US01/13260.
`
`
`Shar1kar, A.U. “A verified sliding window protocol with variable flow
`
`
`
`
`
`
`
`
`
`control”. Proceedings of ACM SIGCOMM conference on Commu-
`
`
`
`
`
`
`nications architectures & protocols. pp. 84-91, ACM Press, NY,NY
`
`
`
`
`
`
`
`
`1986.
`
`* cited by examiner
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`US 7,490,151 B2
`Page 3
`
`
`
`
`D. B. Chapman et al., “Building Internet Firewalls”, Nov. 1995, pp.
`
`
`
`
`
`
`
`
`
`278-297 and pp. 351-375.
`
`
`
`P. Srisuresh eta1., “DNS extensions to Network Address Translators”,
`
`
`
`
`
`
`
`
`Jul. 1998, 27 pages.
`
`
`
`Laurie Wells, “Security Icon”, Oct. 19, 1998, 1 page.
`
`
`
`
`
`
`
`
`W. Stallings, “Cryptography And Network Security”, 2“ Edition,
`
`
`
`
`
`
`
`
`Chapter 13, IP Security, Jun. 8, 1998, pp. 399-440.
`
`
`
`
`
`
`
`
`W. Stallings, “New Cryptography and Network Security Book”, Jun.
`
`
`
`
`
`
`
`
`
`8, 1998, 3 pages.
`
`
`
`Search Report (dated Aug. 20, 2002), International Application No.
`
`
`
`
`
`
`
`
`PCT/US01/04340.
`
`Shree Murthy et al., “Congestion-Oriented Shortest Multipath Rout-
`
`
`
`
`
`
`
`ing”, Proceedings of IEEE Infocom, 1996, pp. 1028-1036.
`
`
`
`
`
`
`
`Jim Jones et al., “Distributed Denial of Service Attacks: Defenses”,
`
`
`
`
`
`
`
`
`Global Integrity Corporation, 2000, pp. 1-14.
`
`
`
`
`
`
`Fasbender, Kesdogan, and Kubitz: “Variable and Scalable Security:
`
`
`
`
`
`
`
`
`Protection of Location Information in Mobile IP”, IEEE publication,
`
`
`
`
`
`
`
`1996, pp. 963-967.
`
`
`
`Laurie Wells (Lancasterbibelrnail MSN COM); “Subject: Security
`
`
`
`
`
`
`Icon” Usenet Newsgroup, Oct. 19, 1998, XP002200606.
`
`
`
`
`
`
`
`Davila J et al, “Implementation of Virtual Private Networks at the
`
`
`
`
`
`
`
`Transport Layer”, Inforn1ation Security, Second International Work-
`
`
`
`
`
`
`
`shop, ISW ’99. Proceedings (Lecture Springer-Verlag Berlin, Ger-
`
`
`
`
`
`
`
`
`many,
`[Online] 1999, pp. 85-102, XP002399276, ISBN 3-540-
`
`
`
`
`
`
`
`
`66695-B, retrieved from the Internet: URL: http://www.springerlink.
`
`
`
`
`
`
`com/content/4uac0tb0heccma89/fulltext.pdf> (Abstract).
`
`
`Alan 0. Frier et al., “The SSL Protocol Version 30”, Nov. 18, 1996,
`
`
`
`
`
`
`
`
`
`
`
`printed from http://www.netscape.com/eng/ssl13/ draft302.b<t on
`
`
`
`
`
`Feb. 4, 2002, 56 pages.
`
`
`
`Davila J et al, “Implementation of Virtual Private Networks at the
`
`
`
`
`
`
`
`Transport Layer”, Inforn1ation Security, Second International Work-
`
`
`
`
`
`
`
`shop, ISW’99. Proceedings (Lecture Springer-Verlag Berlin, Ger-
`
`
`
`
`
`
`
`
`
`
`Page 3 of 62
`
`Page 3 of 62
`
`
`
`
`
`U.S. Patent
`
`
`
`Feb. 10, 2009
`
`
`
`
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`145
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`FIG. 2
`
`Page 5 of 62
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`Page 5 of 62
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`Feb. 10, 2009
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`Sheet 3 of 35
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`US 7,490,151 B2
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`DATA STREAM Q9
`
`INTERLEAVED
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`
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`FIG. 3A
`
`Page 6 of 62
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`Page 6 of 62
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`Feb. 10, 2009
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`Sheet 4 of 35
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`US 7,490,151 B2
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`Page 7 of 62
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`Feb. 10, 2009
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`Sheet 5 of 35
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`US 7,490,151 B2
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`Feb. 10, 2009
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`Sheet 6 of 35
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`US 7,490,151 B2
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`BACKGROUND LOOP-DECOY
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`311
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`FIG. 5
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`Page 9 of 62
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`Feb. 10, 2009
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`Sheet 7 of 35
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`US 7,490,151 B2
`
`
`BACKGROUND LOOP-DECOY
`
`GENERATION
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`320
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`324
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`FIG. 6
`
`Page 10 of 62
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`Page 10 of 62
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`Feb. 10, 2009
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`Sheet 8 of 35
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`US 7,490,151 B2
`
`
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`S40
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`GENERATION
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`S42
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`
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`
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`FIG. 7
`
`Page 11 of 62
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`Page 11 of 62
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`Feb. 10, 2009
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`Sheet 9 of 35
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`US 7,490,151 B2
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`Sheet 14 of 35
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`US 7,490,151 B2
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`Sheet 18 of 35
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`Sheet 19 of 35
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`US 7,490,151 B2
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`Page 22 of 62
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`Page 22 of 62
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`Sheet 20 of 35
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`US 7,490,151 B2
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`Page 23 of 62
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`Page 23 of 62
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`U.S. Patent
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`Feb. 10, 2009
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`Sheet 21 of 35
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`US 7,490,151 B2
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`Page 24 of 62
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`Page 24 of 62
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`Feb. 10, 2009
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`Sheet 22 of 35
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`US 7,490,151 B2
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`2011
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`Page 25 of 62
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`Page 25 of 62
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`Sheet 23 of 35
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`US 7,490,151 B2
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`BE TABLE
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`CE TABLE
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`FIG. 21
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`LINK DOWN
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`2100 /(
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`Page26of62
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`Page 26 of 62
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`U.S. Patent
`
`Feb. 10, 2009
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`Sheet 24 of 35
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`US 7,490,151 B2
`
`
`
`
`
`MEASURE
`
`QUALITY OF
`TRANSMISSION
`PATH X
`
`
`
`MORE
`
`THAN ONE
`
`TRANSMITTER
`TURNED
`ON?
`
`2209
`
`SET WEIGHT
`
`TO MIN. VALUE
`
`DECREASE
`WEIGHT FOR
`PATH X
`
`INCREASE WEIGHT
`FOR PATH X
`
`TOWARD STEADY
`
`
`STATE VALUE
`
`
`
`
`
`
`ADJUST WEIGHTS
`
`FOR REMAINING
`
`PATHS SO THAT
`WEIGHTS EQUAL ONE
`
`
`
`
`Page 27 of 62
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`FIG. 22A
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`Page 27 of 62
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`U.S. Patent
`
`Feb. 10, 2009
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`Sheet 25 of 35
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`US 7,490,151 B2
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`(EVENT) TRANSMITTER
`FOR PATH x
`
`TURNS OFF
`
`
`
`
`2210
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`2211
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`2212
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`2313
`
`2214
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`AT LEAST
`
`DROP ALL PACKETS
`
`ONE TRANSMITTER
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`UNTILATRANSMITTER
`
`TURNED ON?
`
`TURNS ON
`
`SET WEIGHT
`
`TO ZERO
`
`ADJUST WE|GHTS
`FOR REMAINING
`PATHS so THAT
`
`WEIGHTS EQUAL ONE
`
`FIG. 22B
`
`Page 28 of 62
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`Page 28 of 62
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`U.S. Patent
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`Feb. 10, 2009
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`Sheet 26 of 35
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`US 7,490,151 B2
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`Feb. 10, 2009
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`Sheet 27 of 35
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`US 7,490,151 B2
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`Page 30 of 62
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`Feb. 10, 2009
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`Sheet 28 of 35
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`US 7,490,151 B2
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`Page 32 of 62
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`Page 32 of 62
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`U.S. Patent
`
`Feb. 10, 2009
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`Sheet 30 of 35
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`US 7,490,151 B2
`
`2701
`
`RECEIVE DNS
`REQUEST FOR
`
`TARGET SITE
`
`2703
`
`2702
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`2704
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`
`SECURE SITE
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`ACCESS TO
`
`REQUESTED?
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`AUTHORIZED TO
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`RETURN
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`ERROR
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`2706
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`ESTABLISH
`VPN WITH
`
`TARGET SITE
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`FIG. 27
`
`Page 33 of 62
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`Page 33 of 62
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`Page 35 of 62
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`Page 35 of 62
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`Feb. 10, 2009
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`Sheet 34 of 35
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`US 7,490,151 B2
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`3104
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`Page 37 of 62
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`Page 37 of 62
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`
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`U.S. Patent
`
`Feb. 10, 2009
`
`Sheet 35 of 35
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`US 7,490,151 B2
`
`SERVER
`
`PASS DATA UP STACK
`
`GENERATE NEW CKPT_N
`GENERATE NEW CKPT_R
`FOR TRANSMITTER SIDE
`TRANSM|TSYNC_ACK
`CONTAINING CKPT_O
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`CKPT_O=CKPT_N
`GENERATE NEW CKPT_N
`GENERATE NEW CKPT_R
`¥P‘3I’fNT§”Ifi*I’%‘°é“¢'IlcT:EI'3c?<'”E
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`— -
`
`—
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`TRANSMHTER OFF
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`MATCHES TRANSMITTERS
`CKPT_o
`UPDATE RECEIVERS
`CKPT_R
`KILL TIMER, TURN
`TRANSMITTER ON
`
`SEND DATA PACKET
`USING CKPT_N
`CKPT_o=CKPT_N
`GENERATE NEW CKPT_N
`START TIMER, SHUT
`TRANSMITTER OFF
`
`WHEN TIMER EXPIRES
`TRANSMIT SYNC_REQ
`USING TRANSMITTERS
`CKPT_O,STARTTlMER
`
`IECKPT 0 IN SYNC ACK
`MATCHES TRANSMITTERS
`CKPT_O
`UPDATE RECE|VER'S
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`KILL TIMER, TURN
`TRANSMITTER ON
`
`Page 38 of 62
`
`SYNC REQ
`—
`
`FIG. 32
`
`Page 38 of 62
`
`
`
`US 7,490,151 B2
`
`1
`ESTABLISHMENT OF A SECURE
`COMMUNICATION LINK BASED ON A
`
`DOMAIN NAME SERVICE (DNS) REQUEST
`
`CROSS-REFERENCE TO RELATED
`APPLICATIONS
`
`This application is a divisional application of 09/504,783
`(filed Feb. 15, 2000), now U.S. Pat. No. 6,502,135, issued
`Dec. 31, 2002, which claims priority from and is a continua-
`tion-in-part of previously filed U.S. application Ser. No.
`09/429,643 (filed Oct. 29, 1999) now U.S. Pat. No. 7,010,604.
`The subject matter of the ’643 application, which is bodily
`incorporated herein, derives from provisional U.S. applica-
`tion No. 60/106,261 (filed Oct. 30, 1998) and 60/137,704
`(filed Jun. 7, 1999).
`
`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
`
`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
`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,
`
`10
`
`15
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`2
`
`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 from 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 from 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-
`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
`
`Page 39 of 62
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`Page 39 of 62
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`US 7,490,151 B2
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`3
`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 TunneledAgile 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 attached to TARP IP packets
`contains only the address of a next hop router or destination
`server. That is, instead of indicating a final destination in the
`destination field of the IP header, the TARP packet’s IP
`header always points to a next-hop in a series of TARP router
`hops, or to the final destination. This means there is no overt
`indication from an intercepted TARP packet of the true des-
`tination of the TARP packet since the destination could
`always be next-hop TARP router as well as the final destina-
`tion.
`
`Each TARP packet’s true destination is concealed behind a
`layer of encryption generated using a link key. The link key is
`the encryption key used for encrypted communication
`between the hops intervening between an originating TARP
`terminal and a destination TARP terminal. Each TARP router
`
`can remove the outer layer of encryption to reveal the desti-
`nation