What is SSL Certificate Chain in PKI and How Does It Work?

What is SSL Certificate Chain in PKI and How Does It Work?

In-depth Guide on SSL Certificate Chain in PKI

If you are a website owner, you obviously know what installing an SSL certificate on your website means. Not just securing trust and data, it also plays a key role in boosting your website’s ranking in Google. However, what you might not know is that your certificate doesn’t function inside a bubble. Rather, it is a part of something called the SSL certificate chain.

If you want to truly understand what an SSL certificate chain is, you, at the very least, should have a basic idea about public key infrastructure (PKI), as PKI is a trust model that fortifies SSL certificates.

What is PKI in SSL Certificate Chain?

Public Key Infrastructure (PKI) is a system of digital certificates, certificate authorities (CAs), and other related hardware and software that is used to create, manage, distribute, use, store, and revoke digital certificates. PKI is used to secure electronic communications and transactions by enabling the use of digital certificates and public key encryption.

Got a basic understanding of PKI Certificate? Let us discuss what an SSL certificate chain is.

What is an SSL Certificate Chain?

Also known as certificate hierarchy or SSL chain of trust, a certificate chain is a series of SSL certificates that are used to establish trust between a client (such as a web browser) and a server (such as a website). The purpose of the SSL certificate chain is to establish a chain of trust between the client and the server.

When a client establishes a secure connection to a server, it checks the SSL certificate chain to verify the authenticity of the SSL certificate and to ensure that a trusted CA has issued the certificate. If the certificate chain is not valid, the client will not trust the certificate and will not establish a secure connection to the server.

Now that we know how the SSL certificate chain plays a key role in establishing confidentiality between the server and client let us check how it does so.

How does the SSL Certificate Chain Work?

The SSL certificate chain is an important part of the SSL/TLS ecosystem and plays a critical role in establishing trust between clients and servers.

Before we talk about how it works, let us discuss the three components that are involved in the process.

  • Root Certificate– The root certificate is a digital certificate issued by a trusted certificate authority (CA) and is used to sign intermediate certificates and end-entity SSL certificates. It is stored in a “trust store” in most web browsers and is closely guarded by the CA.
  • Intermediate Certificate: Intermediate certificates are signed by the root certificate and used to sign end-entity SSL certificates. They act as a link between the root and server certificates, and there can be one or more intermediate certificates in a chain.
  • Server Certificate: The server certificate is the end-entity SSL certificate that is issued to a specific domain and is used to establish a secure connection between the server and the client. It is signed by one or more intermediate certificates, which are, in turn, signed by the root certificate. The server certificate is installed on the server and is used to authenticate the server to the client.

  • Read more:- https://cheapsslweb.com/blog/what-is-ssl-certificate-chain