Verifying the Signature by PGP

}

Signed, plaintext

document

Generate hash

code using MD5

Decrypt signature

using RSA

Alice

Joy

Mike

Carol

sender’s public key

receiver’s public

key ring

message

signature

key ID attached

to session key

Compare

step1: PGP will retrieves the sender's public key from the public key ring

,using the Key ID in the signature component of the message.

step2: PGP recovers the transmitted message digest using sender's

public key

step3: PGP will compute the message digest for the received message

and compares it to the transmitted message digest to check

whether it is valid or not.