What is a digital certificate? (2023)


  • Maria E. Shacklett,transmundane data
  • Peter Losin,Senior Technology Editor

What is a digital certificate?

A digital certificate, also known asPublic Key Certificate, is used to cryptographically associate ownership of a public key with the owning entity. Digital certificates are used to share public keys used for encryption and authentication.

Digital certificates include the public key to be certified, identifying information about the entity holding the public key, metadata related to the digital certificate, and afirma digitalthe public key created by the issuer of the certificate.

The distribution, authentication and revocation of digital certificates are the main functions of the public key infrastructure (PKI), the system that distributes and authenticates the public keys.

(Video) Digital Certificates Explained - How digital certificates bind owners to their public key

What is a digital certificate? (1)

Public key cryptography is based on key pairs: oneprivate keyto be retained by the owner and used for signing and decrypting, and a public key that can be used to encrypt data sent to the public key owner or to authenticate data signed by the certificate holder. The digital certificate allows entities to share their public key so that it can be authenticated.

Digital certificates are most commonly used in public-key cryptographic functions to initialize the Secure Sockets layer (SSL) Connections between web browsers and web servers. Digital certificates are also used to share keys used for public key encryption and authentication with digital signatures.

Digital certificates are used by all major web browsers and web servers to ensure that unauthorized persons have not modified any published content and to share keys to encrypt and decrypt web content. Digital certificates are also used in other contexts, online and offline, to provide cryptographic security and privacy.

Digital certificates compatible with mobile operating environments, laptops, tablets,Internet of Things (IoT) devicesand networking applications and software help protect websites, wireless networks, and virtual private networks.

How are digital certificates used?

Digital certificates are used in the following ways:

(Video) What is a digital certificate?

  • Credit and debit cards use digital certificates embedded in chips that connect to merchants and banks to ensure transactions are secure and authentic.
  • Digital payment companies use digital certificates to authenticate their ATMs, kiosks, and point-of-sale devices on-premises with a centralized server in their data center.
  • Websites use digital certificates for domain validation to prove they are trustworthy and authentic.
  • Digital certificates are used in secure email to identify one user to another and can also be used to sign electronic documents. The sender digitally signs the email and the recipient verifies the signature.
  • Computer hardware manufacturers build digital certificates into cable modems to prevent theft of broadband services through device cloning.

As cyber threats increase, more organizations are considering attaching digital certificates to all IoT devices operating at the perimeter and within their organizations. The goals are to defend against cyber threats andprotect intellectual property.

What is a digital certificate? (2)

Who can issue a digital certificate?

An entity can create its own PKI and issue its own digital certificates, creating a self-signed certificate. This approach can be useful when an organization manages its own PKI to issue certificates for its own internal use. But certification authorities (CA)—which are considered trusted third parties in the context of a PKI—issue most digital certificates. By using a trusted third party to issue digital certificates, users can extend their trust in the CA to the digital certificates it issues.

Digital Certificates vs. Digital Signatures

Public key cryptography supports several different functions, including encryption and authentication, and allows for a digital signature. Digital signatures are generated using data-signing algorithms so that a recipient can irrefutably confirm that the data was signed by a specific public key holder.

Digital signatures are generated byHashishthe data to be signed with a one-way cryptographic hash; the result is then encrypted with the signer's private key. The digital signature contains this encrypted hash, which can only be authenticated or verified by using the sender's public key to decrypt the digital signature and then running the same one-way hash algorithm on the signed content. The two hashes are then compared. If they match, it proves that the data hasn't changed since it was signed and that the sender owns the public key pair used to sign it.

A digital signature may depend on the distribution of a public key in the form of a digital certificate, but the public key need not be transmitted in this form. However, digital certificates are digitally signed and should not be trusted unless the signature can be verified.

(Video) Why digital certificate?

What types of digital certificates are there?

Web servers and web browsers use three types of digital certificates to authenticate themselves on the Internet. These digital certificates are used to link a domain's web server to the person or organization that owns the domain. They are often referred to asSSL CertificatesAlthoughtransport-layer securityThe protocol has replaced SSL. The three types are as follows:

  1. Domain Validated (DV) SSLCertificates offer the least certainty about the certificate holder. Applicants for DV SSL Certificates only need to prove that they are authorized to use the domain name. While these certificates can guarantee that the certificate holder is sending and receiving data, they offer no guarantees as to who that entity is.
  2. Organisationsvalidiertes (OV) SSLCertificates offer additional security via the certificate holder. You confirm that the applicant has the right to use the domain. Applicants for the OV SSL Certificate are also subject to additional confirmation of their ownership of the domain.
  3. extended validation (VE)SSLCertificates are only issued after the applicant has proven their identity to the satisfaction of the certification authority. The verification process verifies the existence of the entity requesting the certificate, ensures that the identity matches official records and is authorized to use the domain, and confirms that the domain owner authorized the certificate to be issued.

The exact methods and criteria that CAs follow to deploy these types of SSL Certificates to web domains are evolving as the CA industry adapts to new conditions and applications.

There are also other types of digital certificates that are used for different purposes:

  • Code Signing Certificatesmay be issued to organizations or individuals that publish software. These certificates are used to share public keys that sign software code, including software patches and updates. Code signing certificates certify the authenticity of the signed code.
  • Client Certificates, also calleddigital identification, are issued to individuals to bind their identity to the public key in the certificate. Users can use these certificates to digitally sign messages or other data. They can also use their private keys to encrypt data that recipients can decrypt using the public key in the client's certificate.

Advantages of the digital certificate

Digital certificates offer the following advantages:

(Video) What Is The Use Of Digital Certificates?

  • Privacy.When you encrypt communications, digital certificates protectsensitive informationand prevent information from being viewed by persons who are not authorized to view it. This technology protects companies and individuals with large amounts of sensitive data.
  • Easy to use.The digital certification process is largely automated.
  • cost effectiveness.Compared to other forms of encryption and certification, digital certificates are cheaper. Most digital certificates cost less than $100 per year.
  • Flexibility.Digital certificates do not have to be purchased from a CA. For organizations interested in creating and managing their own internal set of digital certificates, a do-it-yourself approach to creating digital certificates is feasible.

Limitations of Digital Certificates

Digital certificate limitations include:

  • Security.Like any other security deterrent, digital certificates can be hacked. The most logical route for a mass attack is if the issuing digital certificate authority is hacked. This gives attackers an entry point to break into the repository of digital certificates that the agency hosts.
  • slow performance.It takes time to authenticate and encrypt and decrypt digital certificates. The wait can be frustrating.
  • Integration.Digital certificates are not a standalone technology. To be effective, they must be properly integrated into systems, data, applications, networks, and hardware. This is not an easy task.
  • Management.The more digital certificates a company uses, the greater the need to manage and track those that expire and need to be renewed. Third parties can provide these services, or companies can choose to do the work themselves. But it can get expensive.

Learn how timing attacks can be usedDecrypt encryption key.

This was last updated onSeptember 2021

Read more About the digital certificate

  • Deploy IoT device certificates to increase network security
  • How do electronic signatures and digital signatures differ?
  • How to get a digital certificate that works for your network
  • Strong security can unlock the promise of the Industrial Internet of Things

related terms

Anonymes FTP (File Transfer Protocol)
Anonymous File Transfer Protocol (FTP) is a method that allows users to access public files from a remote server or file site...See full definition
Reverse brute force attack
A reverse brute force attack is a type of brute force attack in which an attacker enters a common password for multiple...See full definition
Web Authentication API
The Web Authentication API (WebAuthn API) is an application program interface (API) for managing credentials that the Web...See full definition

Dive deeper into identity and access management

  • How do electronic signatures and digital signatures differ?By: GeoffreyBock
  • X.509 CertificateBy: AlexanderGillis
  • 3 Types of PKI Certificates and Their Use CasesBy: IsabellaHarford
  • mutual authenticationBy: PaulKirvan


What is a digital test certificate? ›

An EU Digital COVID Certificate is a digital proof that a person has either. been vaccinated against COVID-19. received a negative test result or. recovered from COVID-19.

How to get an EU digital COVID certificate? ›

You will get your certificate by email within 5 days. You can get your DCC through private providers on this list. People who get a negative antigen test at a private testing service. You should check ReOpen EU to check if it is accepted in the country you are travelling to.

How long is a QR code valid for? ›

The QR code is valid for 24 hours.

Can I fly immediately after Covid vaccine? ›

People are considered fully vaccinated for the purposes of traveling to the United States 2 weeks (14 days) after a dose of an accepted single-dose vaccine or 2 weeks (14 days) after the second dose of an accepted 2-dose vaccine series, regardless of prior COVID-19 disease history.

What is an example of a digital certificate? ›

Client Certificates or Digital IDs are used to identify one user to another, a user to a machine, or a machine to another machine. One common example is emails, where the sender digitally signs the communication, and the recipient verifies the signature.

What is in a digital certificate? ›

A digital certificate uses cryptography and a public key to prove the authenticity of a server, device, or user, ensuring that only trusted devices can connect to an organization's network. They can also be used to confirm the authenticity of a website to a web browser.

How do I get Covid pass on my phone? ›

How to download your COVID travel pass in 4 easy steps!
  1. Ensure you have downloaded NHS App on your phone.
  2. Click on NHS COVID pass, and then click on Travel.
  3. Scroll down and click on the link to download PDF copy.
  4. Select mail from the options and email it to.

How do i download my COVID vaccination certificate? ›

To access your certificate, you can download the COVIDCert NI app. Or, you can log in at the link below for a printable PDF version: Log in to the COVID certificate service.

How do I get my Covid cert? ›

For certificates based on negative RT-PCR tests, a Digital COVID Certificate will be provided by the private RT-PCR testing service. Certificates based on a RT-PCR are valid for 72 hours after the test was taken. To get started, simply choose the service you need below and provide the necessary details on the form.

Can police track QR code? ›

As soon as the beat policeman scans the code, the officer in-charge will not only get a confirmation, but will also be able to track his or her movement through GPS.

How far away do you have to be to scan a QR code? ›

The ideal scanning size to distance ratio is 10:1. Therefore, the code should be roughly 1m (3.2 feet) wide and tall if it is 10m (32 feet) away from the scanner. Making a code bigger will enable the scanner to detect it if it is farther away.

Do you have to pay for QR codes? ›

Static QR Codes are free to use and do not require you to pay anything. Alternatively, dynamic QR Codes come packed with a host of features like tracking, extensive customization, flexibility, and more. You would have to upgrade to a paid QR Code solution for creating dynamic QR Codes.

Do I need a booster shot to travel? ›

Be aware that some countries are requesting evidence that you completed your COVID-19 vaccine course at least 14 days before arriving in their country. They may also require evidence of a booster dose depending on how long ago you completed your COVID-19 vaccine course.

Which COVID vaccine is best? ›

The Pfizer and Moderna vaccines are strongly recommended as safe and effective at preventing serious illness or death from COVID-19.

Can you travel without being vaccinated? ›

If you are not fully vaccinated and allowed to travel to the United States by air through an exception, you will be required to sign an attestation (legal statement) before you board your flight to the United States stating you meet the exception.

What are 3 things included in a digital certificate? ›

Digital certificates include the public key being certified, identifying information about the entity that owns the public key, metadata relating to the digital certificate and a digital signature of the public key the certificate issuer created.

What are the 3 types of certificates? ›

There are three recognized categories of SSL certificate authentication types:
  • Extended Validation (EV)
  • Organization Validation (OV)
  • Domain Validation (DV)

What is a digital certificate and why is it important? ›

Issued by a trust service provider (TSP) or certification authority, a digital certificate ensures that when a person sends information like a digital signature to someone else, the receiver of that information knows they can trust it.

What is a digital certificate quizlet? ›

Digital certificate. A technology that used to associate a user's identity to a public key and that has been digitally signed by a trusted third party.

What is digital certificate and how does it work? ›

A digital certificate is an electronic document issued by a Certificate Authority (CA). It contains the public key for a digital signature and specifies the identity associated with the key, such as the name of an organization. The certificate is used to confirm that the public key belongs to the specific organization.

What is digital certificate also known as? ›

digital certificate, also called public-key certificate, electronic file that typically contains identification information about the holder, including the person's public key (used for encrypting and decrypting messages), along with the authority's digital signature, so that the recipient can verify with the authority ...

How long does it take to download COVID Pass? ›

It may take up to 7 working days for the letter to arrive. This practice is not able to provide you with a letter that shows your COVID-19 vaccination status. Please do not contact the practice about your COVID-19 vaccination status unless you have been advised to by the 119 service.

How long does Covid pass last on phone? ›

If you have an NHS COVID Pass for travel based on a positive NHS PCR test, it will last for 180 days (6 months) after you took the test. If you have a digital NHS COVID Pass, the barcodes will refresh every time you log in. If you download, print or save your NHS COVID Pass, check the expiry date before you use it.

How to update your COVID certificate? ›

If you would like to make an update to a Recovery Certificate, please contact the DCC Service Centre on 1800 807008.

Can someone hack my phone through a QR code? ›

QR codes, as demonstrated, can be used as a vector to compromise your device. The method I explained requires the target to manually download the malicious file, but many other exploits are automatic and stealthy and do not require further actions after scanning the code. Be careful about what you scan.

How do you know if your phone is being tracked by police? ›

How to tell if your cell phone is being spied on
  • Unusual sounds during calls. ...
  • Decreased battery capacity. ...
  • Phone shows activity when not in use. ...
  • Phone takes a long time to shut down. ...
  • Battery temperature feels warm. ...
  • Receiving unusual texts. ...
  • Increased data usage. ...
  • Android.
Sep 1, 2022

Can police track your phone without your knowledge? ›

The law requires—in most situations—that the police get a warrant in order to gather historical cellphone location information kept by cellphone and wireless network providers. The U.S. Supreme Court established this privacy rule for all the country in the 2018 case Carpenter v. United States. (138 S.

What is the purpose of getting a digital certificate? ›

Digital certificates facilitate secure electronic communication and data exchange between people, systems, and devices online. They are issued by Certificate Authorities (CAs) and perform two primary functions: Verifying the identity of the sender/receiver of an electronic message.

What is a digital certificate from a school? ›

Digital certificates present all the same information as a traditional certificate and provide room for additional evidence such as transcripts, honor roll recognition, exam results, worksheets, and dissertation grades.

How does a digital certificate work? ›

A digital certificate is an electronic document issued by a Certificate Authority (CA). It contains the public key for a digital signature and specifies the identity associated with the key, such as the name of an organization. The certificate is used to confirm that the public key belongs to the specific organization.

What does a digital Covid certificate? ›

The certificate makes it easier for you to travel safely through the EU by showing that you have been vaccinated, had a negative test result or recovered from COVID-19.

What are the main features of a digital certificate? ›

Five Beneficial Features of Digital Certificates
  • Certificate Automation.
  • Trusted Identities.
  • Code Signing.
  • Digital Signatures.
  • Qualified Trust.

What are the most important components of a digital certificate? ›

Contents of a digital certificate
  • The distinguished name (DN) of the owner. ...
  • The public key of the owner.
  • The date on which the certificate is issued.
  • The date on which the certificate expires.
  • The distinguished name of the issuing CA.
  • The digital signature of the issuing CA.
Aug 11, 2022


1. Digital Signatures and Digital Certificates
(Computer Science)
2. Intro to Digital Certificates
(Dave Crabbe)
3. What are Digital Signatures? - Computerphile
4. How does HTTPS work? What's a CA? What's a self-signed Certificate?
5. ISE Digital Certificate Administration
(Cisco ISE - Identity Services Engine)
6. Digital Certificates - CompTIA Security+ SY0-401: 6.3
(Professor Messer)
Top Articles
Latest Posts
Article information

Author: Annamae Dooley

Last Updated: 01/02/2023

Views: 6035

Rating: 4.4 / 5 (65 voted)

Reviews: 80% of readers found this page helpful

Author information

Name: Annamae Dooley

Birthday: 2001-07-26

Address: 9687 Tambra Meadow, Bradleyhaven, TN 53219

Phone: +9316045904039

Job: Future Coordinator

Hobby: Archery, Couponing, Poi, Kite flying, Knitting, Rappelling, Baseball

Introduction: My name is Annamae Dooley, I am a witty, quaint, lovely, clever, rich, sparkling, powerful person who loves writing and wants to share my knowledge and understanding with you.