How is an Electronic Communication Digitally Signed?
Before a sender can digitally sign an electronic communication, the sender must first create a public-private key pair. The private key is kept confidential by the sender and is used for the purpose of creating digital signatures. The public key is disclosed generally by posting the key in online databases, repositories, or anywhere else the recipient of the digitally signed communication can access it. To digitally sign an electronic communication, the sender runs a computer program that creates a message digest (or hash value) of that communication. The program then encrypts the resulting message digest using the sender’s private key. The encrypted message digest is the digital signature. The sender then attaches the digital signature to the communication and sends both to the intended recipient. A digitally signed communication might look like this: Subject: Order Author: rqz@ipc.com October 30, 1995 —BEGIN PGP SIGNED MESSAGE— Dear Order Department: We commit to purchase 10,000
