Secure IMRSA Data Security, Inc., Software R&D Engineer (1991)
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MSN MessengerSKYPEYahoo! MessengerQQ
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Cost Savings on Long Distance and Travel
More Responsive Conversations and Collaboration
[Rittinghouse/Ransome 2005]
UNIX / Linux Windows
T. Berson, "Skype (1.3) Security Evaluation," Oct. 2005, http://www.skype.com/security/files/2005-031%20security%20evaluation.pdf
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RFC 2778, A Model for Presence and Instant Messaging, 2000.
RFC 2779, Instant Messaging / Presence Protocol Requirements, 2000.
PRESENTITY
WATCHER
XMPP (eXtensible Messaging and Presence Protocol)
<iq>
<presence>
<message>


Google TalkJabber/XMPP
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Three-party PAKE (Password Authentication and Key Exchange)
RSA
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ECC(RSA)
(factorization)(primality testing)
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P + O = O + P = P for all P E(Zp).
If P = (x, y) E(Zp), then (x, y) + (x, y) = O. (The point (x, y) is denoted by -P, and is called the negative of P)
Let P = (x1,y1) E(Zp) and Q = (x2,y2) E(Zp), where P -Q. Then P+Q = (x3,y3) = R, where
x3 = 2 - x1 - x2
y3 = (x1 -x3) - y1,
elliptic curve E: y2 = x3 + x + 1 over GF(23)
(3, 10) + (9, 7) = (17, 20)
2 • (3, 10) = (7, 12)
(0, 1)
(0, 22)
(1, 7)
(1, 16)
(3, 10)
(3, 13)
(4, 0)
(5, 4)
(5, 19)
(6, 4)
(6, 19)
(7, 11)
(7, 12)
(9, 7)
(9, 16)
(11, 3)
(11, 20)
(12, 4)
(12, 19)
(13, 7)
(13, 16)
(17, 3)
(17, 20)
(18, 3)
(18, 20)
(19, 5)
(19, 18)




MIRACL 5.30bmark, CentOS
HP ProLiant ML 110 G4 [Intel Pentium D Processor 2.8 GHz, 2GB RAM]


MIRACL 5.30bmark, Windows XP
Sony Vaio VGN SZ-38 [Intel Core 2 Duo T7200 (2 GHz), 2GB RAM]



Client-Client
J. Rittinghouse and J. Ransome, Instant Messaging Security, Elsevier Digital Press, 2005.
A.J. Menezes, P.C. van Oorschot and S.A. Vanstone, Handbook of Applied Cryptography, CRC Press, 1996. http://www.cacr.math.uwaterloo.ca/hac/
KR
A
= h(pw
A
(C/S)
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