But what is PKI technology, exactly? And what\u2019s going on in the background of PKI technology that makes it magic? In this ultimate guide, you’ll find everything you should know about PKI technology but are too afraid to ask.<\/p>\n\n\n\n
Editor’s Note:<\/strong> This article is the first in a three-part series that dives into the details of PKI technology. This series explores the roles of PKI technology in IT security<\/a>, provides examples of PKI uses and applications<\/a> that small and mid-size businesses can enjoy, and looks at how PKI technology works<\/a>. <\/em><\/p>\n\n\n\n \u201cPKI technology\u201d is a bit of a misnomer. In a technical sense, it comprises a set of policies, standards, hardware, and software used to create, manage, distribute, store, and revoke digital certificates (more on that momentarily). In a more basic sense, it\u2019s what makes secure, authenticated communication possible over insecure networks.<\/p>\n\n\n\n Does it sound familiar somehow? Yup, PKI IT is the digital version of a passport system where the authorities that issue, renew, or revoke physical passports follow specific processes and rules.<\/p>\n\n\n\n Just like how a passport confirms your identity and enables you to prove your identity when traveling abroad, PKI asserts people, services, and devices’ digital identities and facilitates secure data transmissions over the internet.<\/p>\n\n\n\n Let’s explore five fundamental PKI parts that enable you to protect data, manage encryption, and secure communications. But first, you must understand the three main goals of PKI technology in data and IT security:<\/p>\n\n\n\n To be able to do so, PKI technology counts on a few little helpers (i.e., components). Let’s break down the five most fundamental elements of PKI technology.<\/p>\n\n\n\n Roles in PKI technology<\/em><\/strong>: CAs form the backbone of the trust hierarchy (i.e., the \u201cchain of trust\u201d) that\u2019s used to issue and revoke X.509 digital certificates.<\/em><\/p>\n\n\n\n Certification authorities<\/a><\/strong> are the digital version of the government authorities issuing your passport. A CA, such as Sectigo, is a publicly trusted entity that issues publicly trusted digital certificates to individuals and organizations after conducting a thorough vetting process.<\/p>\n\n\n\n These trusted entities are responsible for maintaining \u201ctrust hierarchies\u201d that digital certificates for websites, users, software and document signing, and many other use cases all chain back to. Different CAs (i.e., root, intermediate, and issuing CAs) serve specific roles based on their place in the trust hierarchy, as illustrated below:<\/p>\n\n\n\n However, it\u2019s important to note that different types of CAs (public vs private CA<\/a>) can issue publicly trusted certificates for use on the internet or private networks, respectively.<\/p>\n\n\n\n Sectigo Private PKI<\/strong> is a managed PKI service that complements your Microsoft CA and expands it to protect the non-Windows devices on your networks.<\/p>\n\n\n\n It works with Sectigo Certificate Manager<\/strong> to simplify and streamline certificate deployment and management across all devices and applications within your ecosystem.<\/p>\n\n\n\n <\/p>\n<\/div><\/div>\n\n\n\n Roles in PKI technology<\/em><\/strong>: Enable secure communication and link the identity of an organization or individual to a public-private key pair.<\/em><\/p>\n\n\n\n A PKI certificate<\/strong> (i.e., X.509 certificate<\/a><\/strong>) is a digital file confirming you are who you’re supposed to be. It\u2019s issued by a trusted third party that confirms the accuracy of the information displayed on the certificate.<\/p>\n\n\n\n Not all certificates are created equal, though. Depending on the level of validation, they can be more or less trusted. Here are a few examples:<\/p>\n\n\n\n PKI technology relies on several types of PKI certificates, such as:<\/p>\n\n\n\n We’ll learn more about their purposes in a minute. For now, it’s essential to know that, despite their different names and purposes, all these certificates typically include the same information, such as:<\/p>\n\n\n\n Roles in PKI technology<\/em><\/strong>: Cryptographic key pairs encrypt and decrypt information, enabling organizations to securely communicate via insecure networks.<\/em><\/p>\n\n\n\n This encryption method uses a single shared private key<\/a> to encrypt and decrypt data. Because this sensitive key serves both roles, it must be securely stored and managed to avoid compromise. As such, both parties (i.e., the sender and recipient) must figure out a way to securely share the private key data before using it to exchange sensitive messages.<\/p>\n\n\n\n Historically, two parties used to meet up face to face to exchange the key so they could first verify the other\u2019s identity. But this approach is no longer feasible on its own in a world of online communications over an insecure network (i.e., the internet). If an attacker gets their hands on that private key, they can use it to decrypt your messages. So, what\u2019s the solution? This is where using a public-private key pair comes into play.<\/p>\n\n\n\n This approach uses a public key in addition to the private key to securely exchange data in insecure channels. The two keys are mathematically related but are still unique. In public key cryptography, only the public key is shared, meaning the private key remains secret. This helps to protect it from being compromised by bad guys.<\/p>\n\n\n\n Sounds great, right? But as with most things in life, there\u2019s a catch: asymmetric encryption is resource-intensive and isn\u2019t great for use at scale. This is why asymmetric and<\/em> symmetric encryption both play a role in the SSL\/TLS handshake (more on that momentarily), which servers and clients use to authenticate and establish secure website connections.<\/p>\n\n\n\n Roles in PKI technology<\/em><\/strong>: Hardware security modules (HSMs), secure tokens, and cloud-based key vaults enable organizations to securely store and manage their cryptographic keys.<\/em><\/p>\n\n\n\n In January 2023, GitHub reported<\/a> that attackers stole three code signing certificates and keys. The certificates were quickly revoked. However, this incident put GitHub and its customers at risk of attack.<\/p>\n\n\n\n A few months later, the CA\/B Forum mandated that all publicly trusted code signing certificates\u2019 keys must be generated and stored on secure hardware (e.g., a FIPS 140-2 Level 2-compliant USB token, a physical HSM, or a cloud-based HSM<\/a>).<\/p>\n\n\n\n No matter which type of certificate you use, secure hardware such as HSMs are a fundamental pillar for the security of PKI technology as they provide strong protection against cybercriminals. Think about it: Stealing a USB key or a physical HSM appliance in a data center is much more difficult for an attacker than stealing a private key stored on a laptop or a database connected to the internet.<\/p>\n\n\n\n Roles in PKI technology<\/strong>: These revocation mechanisms help to identify stolen and\/or otherwise compromised certificates and invalidate them ahead of their assigned expiration dates.<\/p>\n\n\n\n Have you ever seen this error message while browsing the internet?<\/p>\n\n\n\n The message above is an example of what you see when a website you’re visiting uses a certificate that has been revoked. When you visit a website, your browser verifies its SSL\/TLS certificate validity. To do so, the browser can use different methods:<\/p>\n\n\n\n Cool huh? They’re two different processes with <\/a>pros and con<\/a>s to each<\/a> that ultimately share the same goal: alerting the client about whether a website is using a revoked certificate. This prevents users from interacting with potentially dangerous websites (e.g., phishing or phony) and you, as a website owner, from data breach consequences (e.g., legal action, fines).<\/p>\n\n\n\n OK, now that you’ve familiarized yourself with PKI technology key elements, let’s see how they work together.<\/p>\n\n\n\n In a nutshell, the way PKI IT security works boils down to three salient points:<\/p>\n\n\n\n For example, when a user visits your website, their client (browser) and the server engage in a \u201cTLS handshake<\/a>.\u201d This process determines how the two parties will communicate securely (i.e., using combinations of cryptographic algorithms and functions). Here\u2019s a quick overview of the process:<\/p>\n\n\n\n If you want to know more about it and get into the nitty-gritty of the process, stay tuned for my next two articles, which will describe the ins and outs of how PKI technology works and how small businesses and mid-size organizations can use it to improve their security.<\/p>\n\n\n\n So, where can you, as an IT professional, use this wonder of technology to make your organization more secure and trustworthy?<\/p>\n\n\n\n Want to learn more about these and other specific PKI uses with examples geared for small and mid-size businesses? Check out our other article on PKI use cases to learn more.<\/p>\n\n\n\n By facilitating authentication and ensuring data privacy and integrity, PKI technology offers many advantages for organizations and their customers:<\/p>\n\n\n\n While using public PKI technology and certificates is great for protecting external-facing resources, it\u2019s crucial that you don\u2019t ignore your organization\u2019s internal security needs. A private PKI allows you to operate an internally trusted CA that gives you greater control of your IT ecosystem and all of the devices, users, and applications within it.<\/p>\n\n\n\n Do you want to implement an internal PKI within your organization? Excellent! Sectigo Private PKI<\/strong><\/a> can help you do precisely that. This intuitive managed PKI platform eliminates many of the burdens associated with running an internal CA.<\/p>\n\n\n\n Whether you\u2019re looking to create a new private CA or want to enhance your existing one, Sectigo Private PKI will help you streamline the process and get back to focusing on other critical responsibilities. <\/a><\/p>\n\n\n\n PKI technology is at the base of a secure digital world. It protects sensitive data, code, and communications while authenticating parties and identities. Now that you know PKI down to the tiniest detail, you’re ready to experiment with it firsthand.<\/p>\n\n\n\nWhat Is PKI Technology?<\/h2>\n\n\n\n
5 Key Elements of PKI Technology<\/h2>\n\n\n\n
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1. Certification Authorities (CAs)<\/h2>\n\n\n\n
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<\/figure>Take Your Existing Microsoft CA to the Next Level with Sectigo Private PKI<\/h2>\n\n\n\n
2. Digital Certificates<\/h3>\n\n\n\n
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Different Types of PKI Certificates Serve Different Roles in PKI IT Security<\/h4>\n\n\n\n
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3. Cryptographic Key Pairs<\/h3>\n\n\n\n
Key Pairs in Private Key Cryptography (Symmetric Encryption)<\/h4>\n\n\n\n
Key Pairs in Public Key Cryptography (Asymmetric Encryption)<\/h4>\n\n\n\n
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4. Secure Key Storage<\/h3>\n\n\n\n
5. Certificate Revocation Mechanisms (i.e., CRLs and OCSP)<\/h3>\n\n\n\n
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How Does PKI Technology Work?<\/h2>\n\n\n\n
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5 Examples of Where You Can Use PKI Technology Within Your Organization<\/h2>\n\n\n\n
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PKI Technology: Advantages<\/h2>\n\n\n\n
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Take Your Security to the Next Level with Private PKI<\/h3>\n\n\n\n
Final Words About Demystifying PKI Technology: An Essential Guide for IT Security Professionals<\/h2>\n\n\n\n