5. Hash Function Jrf843kjfgf*£$&Hdif*7oUsd*&@:<CHDFHSD (** This is a really long message about Bill’s… Asymmetric Encryption Message or File Digital Signature 128 bits Message Digest Calculate a short message digest from even a long input using a one-way message digest function (hash) Signatory’s private key Py75c%bn&*)9|fDe^bDFaq#xzjFr@g5=&nmdFg$5knvMd’rkvegMs” private
6. Verifying a Digital Signature Jrf843kjf gf*£$&Hd if*7oUsd *&@:<CHD FHSD(** Py75c%bn&*) 9|fDe^bDFaq #xzjFr@g5= &nmdFg$5kn vMd’rkvegMs” Asymmetric decryption (e.g. RSA) Everyone has access to trusted public key of the signatory Signatory’s public key Digital Signature This is a really long message about Bill’s… Same hash function (e.g. MD5, SHA…) Original Message Py75c%bn&*) 9|fDe^bDFaq #xzjFr@g5= &nmdFg$5kn vMd’rkvegMs” ? == ? Are They Same?
10. August 8, 2009 Signature algorithm identifier validity signature Subject public key info x.509 VERSION CERTIFICATE SERIAL NO ALGORITHM PARAMETER ISSUER NAME NOT BEFORE NOT AFTER SUBJECT NAME ALGORITHMS PARAMETERS KEY ISSUER UNIQUE IDENTIFIER SUBJECT UNIQUE IDENTIFIER EXTENSION ALGORITHMS PARAMETERS ENCRYPTED
42. Database Schema August 8, 2009 Registration Repository Login Repository Registration no Registration form CSR Date Date of Registration Customer_id Login Name Password Registration no
43. August 8, 2009 Certificate Repository Revocation Repository Certificate Serial No Type of Certificate Customer_id Date of Issue Expire Date Registration no certificate Certificate serial no Expire Date Revocation Date Certificate
44. August 8, 2009 Signature Repository Trusted root Certificate Repository Message_id Signature Validity Algorithm Certificate Serial no Root_id Certificate Serial no CA name Date of Publish Certificate
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