Like this CertiGuide? Get it in PDF format!
Click Here!
Use coupon code "certiguide" to save 20%!
(Expires 2004/12/31)

Also available: 300-question Security+ practice test!
Get It Here!

Custom Search







Table Of Contents  CertiGuide to Security+
 9  Chapter 4:  Basics of Cryptography (Domain 4.0; 15%)
      9  4.2  Concepts in Using Cryptography
           9  4.2.2  Integrity

Previous Topic/Section
4.2.2  Integrity
Previous Page
Pages in Current Topic/Section
1
23
Next Page
4.2.3  Authentication
Next Topic/Section

4.2.2.1  Digital Signatures
(Page 1 of 3)

A Digital Signature is an electronic signature of a document, created by using asymmetric encryption. A digital signature is different from a handwritten signature, because a handwritten signature tends to be the same over time, but a digital signature differs depending on the data being signed. A digital signature is used by a document’s receiver to verify that:

the message has not been tampered with since it was signed (data integrity)

the person who supposedly sent the message really is who they say they are

Typically this is accomplished via encryption with a private key known only by the message sender, and decryption with the public key.

Keep in mind that it is computationally more expensive to encrypt a message than to apply a hashing algorithm to it, that messages sent between parties can be very large (such as file transfers), and the time taken to encrypt data increases the larger the amount of data is. This led researchers to combine the ideas of hashing (with an algorithm like MD5) and encryption, to create a digital signature by encrypting only the document’s message digest hash value, rather than the entire contents of the message.

Digital Signatures

A Digital Signature is an electronic signature of a document, created using asymmetric encryption.

Digital Signatures can be used to verify message integrity and sender identity.



Previous Topic/Section
4.2.2  Integrity
Previous Page
Pages in Current Topic/Section
1
23
Next Page
4.2.3  Authentication
Next Topic/Section

If you find CertiGuide.com useful, please consider making a small Paypal donation to help the site, using one of the buttons below. You can also donate a custom amount using the far right button (not less than $1 please, or PayPal gets most/all of your money!) In lieu of a larger donation, you may wish to consider buying an inexpensive PDF equivalent of the CertiGuide to Security+ from StudyExam4Less.com. (Use coupon code "certiguide" by December 31, 2004 to save 20%!) Thanks for your support!
Donate $2
Donate $5
Donate $10
Donate $20
Donate $30
Donate: $



Home - Table Of Contents - Contact Us

CertiGuide for Security+ (http://www.CertiGuide.com/secplus/) on CertiGuide.com
Version 1.0 - Version Date: November 15, 2004

Adapted with permission from a work created by Tcat Houser et al.
CertiGuide.com Version Copyright 2004 Charles M. Kozierok. All Rights Reserved.
Not responsible for any loss resulting from the use of this site.