Digital Signatures and Certificates

Digital signatures ensure the authenticity, integrity, and confidentiality of digital transactions across various sectors. 

As someone with over 7 years of experience in the field of cybersecurity, I cannot assert more on how important digital signatures can be. Consider the scenario when you wish to sign a contract with a person who is not physically present in the same region as you do. 

Can you travel to a location in order to execute a contract? No, right? 

Creating a digital signature proves to be very helpful in situations like these. I’ve curated this guide on digital signatures for yor to have a comprehensive understanding of what they are essentially. Happy reading!

What is a Digital Signature?

A digital signature is a mathematical approach for authenticating and validating the accuracy and uniformity of an electronic message, record, document, software etc. A verified digital signature provides considerably greater fundamental protection and security than a handwritten signature, as it always helps to sign contacts remotely.

You may use a digital signature for entering into global transactions and contracts. Many countries such as the USA and India have given digital signature use a legal status and are treated the same way as a handwritten signature.

How Do Digital Signatures Work?

With the question of what a digital signature is now solved, let’s understand how digital signatures work. A digital signature online is based on the concept of public key and private key, better known as public key cryptography. 

A digital signature is created with a mathematical function known as the hash function using both public and private keys. In my experience, I have never faced any security issues with digital signs.

This is because it works on the basis of encryption and decryption. In essence, at the time of creating the digital signature, a private key encryption is used and while decrypting, the public key of the signer is used. We usually make use of the public key cryptography method to authenticate digital signatures. 

If you face any hiccups during a digital signature verification online, it could be a clear indication that the data has been tampered with. 

Advantages and Disadvantages of Digital Signatures

In my experience, digital signatures have acted like a boon,  but it also comes with its own set of drawbacks. 

Advantages

Let’s have a look at the advantages first:

• Data security: Safety features are incorporated with digi-signatures to ensure that the genuine signatures remain legitimate and authentic and that no legal record or document is altered. 

• Time stamping; This feature allows the marking of the date and time of the digital signature. Circumstances like stock trading, issuance of lottery tickets, and critical legal proceedings are some of the examples where the timestamping of digital signatures is important.

• Globally recognized and legally compliant: A digital signature and digital certificate is recognized throughout the world as the public cryptography standard guarantees that the information generated and stored is original and reliable. More and more countries are accepting the legal status of digital signs and making contracts digitally signed as legally binding.

• Less time-consuming: With the help of digital signature, you can easily sign contracts and enter into global transactions very easily. It is a hassle-free process where no physical document signing is required.

• Cost-effective method: Storing and managing documents requires a lot of space and manual effort. With the advent of digital signatures, companies can save costs on these avenues.

• Reliability: Digital authorization enhances the record-keeping procedures for the companies by establishing a verification trail. Digital signature application captures and saves everything digitally and reduces errors in the record-keeping procedure.

Disadvantages

Let’s check out the disadvantages too:

• Technology dependence: Digital signatures are susceptible to cybercrimes like data theft, phishing, and hacking. This is why businesses adopting digital science need to make sure that their computer systems are safe and secure.

• Complex method: Setting up and using a digital signature can be tough, especially for elderly people or those who are not accustomed to the way it works. This may give rise to errors. 

• Low acceptance: Creating digital signature online and using the same in underdeveloped and developing nations is still a challenge. Since the use of technology is very limited in underdeveloped nations, it will require considerable time to replace traditional handwritten signatures.

How to Create a Digital Signature?

Let’s talk about the entire process of creating a digital signature. With my expertise in this field, I have illustrated the digital signature process with this step-by-step guide, provided below:

1. Firstly, the original information is converted into a message digest using a hash (#) function to protect the integrity of the data.

2. The value of a hash is unique to the particular data and even a little bit of change or modification will result in a distinct value.

3. The original message is encrypted with the use of the hash function by employing the private key of the sender of the message.

4. The message is then sent to the receiver in an encrypted form. The receiver decrypts such data using the particular public key of the sender.

5. After decrypting the message, the same hash function is applied so as to produce a similar digest.

6. Lastly, it compares the newly produced hash with that of the original message. If both the result matches, then it indicates that the integrity and authenticity of the data is intact. If not, it means the data has been tampered with.  

Difference Between Digital Signature and Electronic Signature

A lot of people often get confused between an electronic signature and digital signature. Let me illustrate the major differences between e-signature and digital signature below: 

Digital Signatures: Use Cases

In my experience, certain companies that significantly operate on contracts use digital signature services. Here, I have listed the most common digital signature use cases:

• Government: Digital signatures are commonly used by government authorities to handle contracts, execute tax returns, authorize laws, and conduct various government interactions. However, government organizations use stringent laws, rules, and regulations while using digital and electronic signatures. 

Every time I authenticate any information using a digital signature, I have to follow certain rules and regulations provided by the government authorities.

• Manufacturing: Manufacturing companies use digital signatures to speed up multiple tasks like product designing, quality control, production improvement, sales, and marketing. The National Institute of Standards and Technology Digital Manufacturing Certificate and the International Organisation for Standardisation oversee the execution of electronic and digital signatures in the manufacturing sector.

• Healthcare: I have seen numerous healthcare organizations using digital signs to enhance data protection and security. They also use it to accelerate the admission process in hospitals, and improve therapeutic and management procedures. However, they are required to abide by the rules contained in the Health Insurance Portability and Accountability Act, of 1996.

Digital Certificates

In my organisation, we need to ensure that a digital signature certificate is issued by a trustworthy third-party. In essence, it verifies and authenticates the sender's identity to the recipient and vice versa. 

An entity known as a Certificate Authority (CA) issues a digital certificate to confirm the identity of the certificate holder.  A digital signature certificate online is used to link a public key to a specific person or business. It must contain the following particulars:

• Name of the certificate holder.
• The unique serial number that is associated with is used to identify a particular individual, company, or entity.
• The expiration date of the digital certificate.
• A copy of the public key of the certificate holder that is used for decrypting digital signatures and messages.
• Digital signature of the authority that issues the certificates.

Wrapping Up

Security and confidentiality act as the stronghold of any company. Digital signatures pack quite a punch in this case. And with technology evolving day by day, measures to strengthen security can only get better from here. 

With this nugget of wisdom, I conclude this guide. if you want to further explore this field as a career, I strongly recommend taking up meticulously chosen courses available on upGrad. These courses are ideal for enthusiastic and dedicated people who are willing to further develop their expertise.

Frequently Asked Questions

1. What are three digital signatures?

Typically, digital signs can be classified mainly as email signing certificates, document signing certificates, and code signing certificates.

2. Where are digital signatures used?

Digital signatures are used in a variety of areas. Some of the most common digital signature use cases are software distribution, financial transactions, email service providers, signing electronic contracts, etc

3. What is a digital signature and its purpose?

A digital signature is a mathematical function used for authenticating and validating the integrity of a message. They help protect the originality, authenticity and integrity of information and to identify the identity of the sender. 

4. How is a digital signature verified?

A digital signature is verified following the encryption and description method of the public-private key. The signature is decrypted using the public key of that particular private key so that the original value of the hash matches the decrypted hash result.

5. Is eSignature legal?

Electronic signs have been accorded legal status in various countries, such as the USA, and India through their country’s laws. In India, e-signatures have been provided legal recognition under the Information Technology Act 2000.

6. What is a digital signature in PDF?

A digital signature contained in a PDF is treated the same as a handwritten signature if the integrity and authenticity of the digital signature remain intact. 

7. How do I create a digital signature for a PDF?

You can create a digital signature in Word or a PDF, with the help of ‘sign’ option available in the top toolbar. From the Tools menu, select  ‘fill and sign’. Click on the PDF and select ‘apply’ to the place where you want to put the digital sign. You can find the digital signature tool in various applications to sign PDFs. 

8. How can I use a digital signature?

You can use a digital signature for signing electronic contracts, and agreements. First, use a digital signature application and then add your digital signature via that application to the agreement.

9. Which app is used for digital signatures?

There are various applications available to create digital signatures out of which the most commonly used ones are DocuSign, OPSign, Adobe Acrobat Sign, etc.

10. Why do we need a digital signature?

A digital signature acts as an evidence about the identity of the sender and also illustrates the integrity of the information.