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Page 1: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-
Page 2: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

Page 3: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

Page 4: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

Page 5: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

• 𝑀 → 0,1 128

•⇒

•⇒

Page 6: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

Page 7: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

Page 8: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

Page 9: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

Page 10: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-
Page 11: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

Page 12: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

⇒⇒

Page 13: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-
Page 14: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-
Page 15: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

• 244.3

244.55

Page 16: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

• 246.6

• 249.3

244.55

Page 17: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

•249.3

244.55

Page 18: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

Page 19: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

Page 20: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

Page 21: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

Page 22: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

• 𝑖

• 𝐵𝑘′ 𝐵𝑘 𝑊𝑆𝑖′ 𝑊𝑆𝑖•

Page 23: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

2−128 2−160

• 𝑁𝛿𝑀

Page 24: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

•𝛿

• 𝐷 𝑉 𝑠

• 𝛿𝑀 𝑠

Page 25: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

• (𝛿𝐵, 𝛿𝑊𝑆)

𝛿𝐵

Page 26: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

• 𝛿𝐵

• 𝛿𝐵

• ⇒ =

Page 27: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

𝑈𝑖 𝐷𝑉𝑖𝑉𝑖 𝐷𝑉𝑖

𝑈𝑖\V𝑖

𝑉𝑖𝑈𝑖 = 𝑉𝑖 𝐷𝑉𝑖

•𝑀𝑖 𝑎 ⊕𝑀𝑗 𝑏 = 0/1

Page 28: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

Page 29: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-

Page 30: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-
Page 31: Need Security Against Digital Signature Forgeries - … › system › files › Stevens-CWI-at-TUE-event...Legitimate website certificate CA certificate Serial 015 . i fax chosen-