In today's digital world, information security is essential. A digital signature is a tool that ensures the authenticity and integrity of electronic documents. In this blog post, we'll explain what a digital signature is and how you can use it to protect your online communications and transactions.
A digital signature is used to verify the authenticity of an electronic document or message. Unlike a handwritten signature, which identifies a person in the physical world, a digital signature verifies the sender’s identity in the digital world.
It is based on public-key cryptography. The process involves the use of a key pair: a private key, which only the signer possesses, and a public key, which is shared with recipients. These keys are mathematically related in such a way that any document signed with the private key can only be verified using the corresponding public key.
When a digital signature is created, a cryptographic algorithm is applied to a document or message to generate a unique, encrypted summary known as a “hash” or “cryptographic digest.” This summary is encrypted using the signer’s private key, thereby creating the digital signature. The original document and the digital signature are sent to the recipient.
When the recipient receives the document and the digital signature, they can use the sender’s public key to verify the authenticity of the signature. By applying the same cryptographic algorithm to the received document, a new digest is generated. This summary is then compared to the decrypted summary of the digital signature using the public key. If the summaries match, it can be concluded that the document has not been altered since the digital signature was created, and that the sender is who they claim to be.
There are several options and applications available for adding a digital signature to a document. Below, we’ll describe the process using two free and widely used applications. You can download this Digital Signature Guide if you’d like to save it and refer to it later.
When you open the application, the Control Panel appears, offering three functions:
First, select the files you want to sign by clicking the “Select Files” button, which opens a window to browse for their location. The screen will display a list of all selected files.
Next, use the “Select Certificate” button to choose the identification of the representative who will sign the document.
The output directory allows you to select the folder where you want to save the signed documents. The “View Output Folder” button takes you directly to the location of the signed files.
Finally, you can select the signature options to include: sign without a timestamp or sign with a timestamp.
It also allows you to specify the Reason for Signing and the location of the Visible Signature on the document.
There are multiple configuration options regarding placement; you can specify the pages as well as the position manually or using standard settings.
After defining the desired signature settings, click“Start Operation.” The document will be saved in the folder you previously selected.
Timestamping is an online mechanism that allows you to prove that a set of data has existed and has not been altered since a specific point in time.
The procedure is identical to that described for signing, without the need for an electronic certificate.
Simply select the files in the box and click “Start Operation.”
The details of the associated signatures and time stamps will be displayed at the bottom, where you can view the reference file and the verification report.
In conclusion, the digital signature is a powerful tool for ensuring the authenticity and integrity of electronic documents. By using cryptographic technology, the digital signature provides security for online communications and transactions, preventing tampering and repudiation of information. With applications like Adobe Acrobat Reader and XolidoSign, you can easily add digital signatures to your documents. Protect your digital communications and take advantage of the benefits of the digital signature!
Image by vectorjuice on Freepik
Image by DilokaStudio on Freepik