Digital signature and digital certificate – what is the difference?

messi62

When you think about the security of your online transactions, you will definitely come across digital signatures and certificates. These elements are the basis for protecting confidential data.

You may be wondering how they work together to enhance security or what sets them apart. Stay with us as we explore the differences between a digital signature and a digital certificate , from how they work to their uses, benefits, and limitations. Let's start with the basics.

Table of contents

What is a digital signature?
How does a digital signature work?
Where are digital signatures used and who uses them?
How to get a digital signature?
What is a digital certificate?
Where are digital certificates used and who uses them?
How to get a digital certificate?
Benefits of Digital Certificates
Disadvantages of digital certificates
What is the difference between digital signatures and digital certificates?
What is a digital signature?
A digital signature is a type of electronic signature that mobile app development service uses cryptographic technology to authenticate the origin and integrity of digital documents, messages, or software. It uses a mathematical algorithm to create a unique digital fingerprint, or “signature,” for a specific piece of data. This signature is unique to the sender and the signed content, providing confidence in the identity of the sender and ensuring that the data remains intact during transmission.




Digital signatures are classified as follows:

Class 1 Signatures (Email Signatures) : These signatures verify the association between an email address and its rightful owner, ensuring the authenticity of the email.
Class 2 signatures (person-based signatures) : This type of signature verifies a person's identity by comparing it to a pre-checked database.
Class 3 Signatures (Personally Attested Signatures) : These signatures are issued after verification of the identity of the person submitting the application, providing a higher level of trust and verification for critical financial transactions such as online trading platforms and electronic trading.
Now let's see how they work, step by step.

How does a digital signature work?
Creation : To sign a digital document, the signatory first creates a unique digital signature using a cryptographic algorithm as specified in the Digital Signature Standard. This algorithm ensures the security and uniqueness of the signature.
Encryption : The digital signature is then encrypted using the signatory's private key , which is part of a key pair associated with a digital signature certificate. This certificate, issued by a trusted Certificate Authority , contains information about the signatory's identity and public key.
Attachment : An encrypted digital signature is attached to a digital document, either as a separate file or integrated into the document itself. This process ensures that the signature is inseparable from the document it authenticates.
Verification : Upon receiving a digitally signed document, the recipient uses the signatory's public key, obtained from the digital signature certificate, to decrypt the signature. This step verifies the authenticity of the signature and its connection to the document.
Integrity check : The recipient performs an integrity check on the document using a hash function. It verifies that the document has not been altered since it was signed, thus preserving its integrity.
Authentication : If the decrypted signature matches the document and the integrity check passes, the recipient can be confident that the document is genuine and has not been tampered with.