A digital signature can be used with any kind of message, whether it is encrypted or not, simply so that the receiver can be sure of the sender's identity and that the message arrived intact. A digital certificate contains the digital signature of the certificate-issuing authority so that anyone can verify that the certificate is real.

How It Works

1. You copy-and-paste the contract (it's a short one!) into an e-mail note.
2. Using special software, you obtain a message hash (mathematical summary) of the contract.
3. You then use a private key that you have previously obtained from a public-private key authority to encrypt the hash.
4. The encrypted hash becomes your digital signature of the message. (Note that it will be different each time you send a message.)

1. To make sure it's intact and from you, your lawyer makes a hash of the received message.
2. Your lawyer then uses your public key to decrypt the message hash or summary.
3. If the hashes match, the received message is valid.

Also see hashing and Digital Signature Standard.

Getting started with digital signatures

To explore how digital signatures are used in the enterprise, here are some additional resources:

Personal digital certificate pros and cons: Are you considering creating a personal digital certificate for your company? Learn about the pros and cons of the technology and the proper steps to follow for issuing these certificates.

Understanding multifactor authentication features in IAM suites: Do you think your organization's multifactor authentication strategy works effectively with your IAM suite? Get a better understanding of multifactor authentication, your IAM suite options and best practices for deployment.

Read more about it:
>>	The American Bar Association provides guidelines for the use of digital signatures.
>>	The World Wide Web Consortium (W3C) describes its own Digital Signature Initiative.
>>	SearchSecurity.com provides links to more information about digital signatures.