Digital Signatures are a very important aspect of Public Key Infrastructures. Not to be confused with Digital Certificates, Digital Signatures are used for authentication purposes and are added at the bottom of emails and other documents.
Using two mathematical algorithms, a form of asymmetric cryptography, forms digital Signatures. The two Digital Signatures are given, one for signing documents, the other for verifying other signatures.
Digital Signatures are used in the same aspect as written signatures. However, Digital Signatures offer significant advantages over written signatures. The Digital Signature is added to anything including Emails to other documents, however in the terms of discussing security issues, all forms of data that are signed with Digital Signatures are referred to as “messages”.
Digital Signatures serve the role of the private and public key in a Public Key Infrastructure. When someone applies for a public key, they will be issued a digital certificate; their digital signature plays an important role in their PKI due to its importance in the digital certificate.
The earliest Digital Signatures were created using the RSA algorithms. However, there have been many advances in Digital Signatures over the years and this includes more complex algorithms to prevent hacking. To prevent hacking users of Digital Signatures are advised to first hash their message and then sign only the hashed form.
Hashing is the process of taking your message and shortening it into a digest form, sometimes this is referred to as a digital fingerprint. The benefits of applying your
Digital Signature to the hashed method includes the fact that your signature will be considerably shorter, making your message more efficient, creating compatibility, and creating a message that is true.
The main benefit of using digital signatures is that the receiver has validation that the author of the message is who he or she claims to be. The impact of these benefits is overwhelming. Without adequate verification of the author’s identity, many transactions would not take place.
Digital Signatures also help to prove that a message has not been changed. Even if a message is encrypted, it may have its message or content changed during the decryption procedure. If this is to occur, the digital signature will not be authentic, and the receiver will easily identify that something is wrong with the message.
It is a good idea to use trusted time stamping with digital signatures due to the fact that digital signatures don’t automatically include the date that the message was signed. This can have serious negative consequences due to the fact that someone could take an old message and sign it at a later time. Trusted time stamping is an effective tool that will prevent this type of digital signature abuse.
To recap, if you were going to use a digital signature, you would create a message and have it in your email. After you have created your message you will hash it with the appropriate software. Once the message is hashed, you will use your private key and encrypt your message. Your digital signature is automatically included in the message.