What is a Digital Signature?

A digital signature is an electronic signature that uses cryptographic techniques to ensure the security and authenticity of a digital message or document. Unlike traditional handwritten signatures, digital signatures are mathematically based and highly secure, making them more trustworthy and difficult to forge.

Digital signatures are based on Public Key Infrastructure (PKI), which involves a pair of keys:

• A private key (known only to the signer)
• A public key (available to everyone for verification)

The private key is used by the signer to create the digital signature, and the public key is used by the recipient to verify the signature's authenticity and ensure the document has not been altered.

How to Obtain a Digital Signature?

Obtaining a digital signature certificate is a straightforward process. Here’s how you can get one:

1. Choose a Certifying Authority:
   • A certifying authority (CA) is an organization that is authorized to issue digital signature certificates. In India, some of the prominent Certifying Authorities include eMudhra, Sify, and NSDL. You can choose a CA based on your requirements and location.
2. Complete the Application Form:
   • You will need to fill out an application form with your personal or organizational details. This typically includes your name, address, and identification proof.
3. Submit Documents:
   • Submit supporting documents like a government-issued ID, address proof, and photographs (depending on the type of digital signature you require).
4. Verification:
   • The Certifying Authority will verify your documents and process the application. Once verified, the CA will issue the digital signature certificate.
5. Install the Certificate:
   • After issuance, the digital signature certificate can be stored in a USB token or smart card for secure usage. It will be valid for a certain period (typically 1-3 years), after which it needs to be renewed.

Types of Digital Signature Certificates (DSC)

Digital signature certificates are categorized into three types based on the level of security:

1. Class 1:
   • These certificates are used for individuals and provide basic authentication for email and personal use.
2. Class 2:
   • These certificates are used for individuals or organizations to file documents with the government. They provide higher security than Class 1 certificates.
3. Class 3:
   • These certificates are used for high-security transactions, such as online trading, e-commerce, and legal documents. They require the signer to appear in person before the Certifying Authority.