The University of SydneyPage 48large messagemH: HashfunctionH(m)digitalsignature(encrypt)Bob’s privatekey K B-+Bob sends digitally signed message:Alice verifies signature, integrity of digitally signed message:
KB(H(m))-encrypted msg digestKB(H(m))-encrypted msg digestlarge messagemH: HashfunctionH(m)digitalsignature(decrypt)H(m)Bob’s publickey K B+equal?Digital signature = signed message digest