Document Document SHA256 SHA256 - PowerPoint PPT Presentation

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Document Document SHA256 SHA256 Ç!”$£”(@0 = Ç!”$£”(@0 Ç!”$£”(@0 (digest) (digest) (digest) Sign Verify K?çW”S0* (signature)

(Modified) Document Document SHA256 SHA256 Ç!”$£”(@0 ≠ 5M/”ò*G2 5M/”ò*G2 (digest) (digest) (digest) Sign Verify %d2|<D+ (signature)

+ Digital Certificate Name: Alice Address: via Galliera, 3 email: alice@unibo.it

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+ Digital Certificate Name: Alice Address: via Galliera, 3 email: alice@unibo.it X!çW”S0* (signature)

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+ Certificate CA4 Certificate CA2 sign Certificate Certificate CA5 sign CA1 Certificate CA3 sign sign Certificate CA6 sign Certificate Alice sign sign

+ Certificate Certificate Bob Elon sign sign Certificate Certificate Charlie Gwen sign sign Certificate Certificate Frank Dana Certificate Alice sign sign sign

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Document SHA256 Ç!”$£”(@0 (digest) Sign Verify K?çW”S0* (signature)

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Digital Certificate Name: Alice Document SHA256 (signatu re) Ç!”$£”(@0 (digest) Sign Verify K?çW”S0* (signature)

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Return Digital Certificate Timestamp + Name: Alice Signature Document SHA256 CA signature ò<+4&H1ì (signature) Ç!”$£”(@0 (digest) Sign Sign Digital Certificate Name: TSA 2020-10-07T1 K?çW”S0* 9F\?’AH§ Document 5:57:42+00:00 (signature) (digest) (timestamp) Other CA signature SHA256 Request timestamping to TSA

Digital Certificate Name: Alice CA signature K?çW”S0* Alice Document Certificate (signature) 2020-10-07T1 ò<+4&H1ì TSA Digital Certificate 5:57:42+00:00 Certificate (signature) Name: TSA (timestamp) Other CA signature

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H(“heads”) H(“tails”) ● ∙ ∙

● H(“1”) -> HD57cb4jiuKlo98hgf . . . H(“99”) -> i902And3òjam32sì34d

● H(“+39 300 0000000”) -> 1A57cb4X2uKlo98hgf . . . H(“+39 399 9999999”) -> ò20bAnd3òjam32sazè2

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Mirko Zichichi associato a X1457cb4jiuKlo98hgf Indirizzo Pubblico (alphanumeric)

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