The difference between .CER and .PEM certificates lies in their encoding and usage.
The .CER extension typically represents a binary X.509 certificate, while the .PEM extension is used to encode X.509 certificates in Base64.
Here’s a detailed discussion of the differences between the two:
.CER Certificate
A .CER certificate is a binary X.509 certificate, which means it’s encoded in binary format.
This type of certificate is often used in Windows environments and can contain the public key of a digital certificate.
Note that the .CER extension only indicates the encoding type of the certificate and does not necessarily dictate its contents.
What are CER certificates used for?
CER certificates are mostly used in security protocols like SSL/TLS to ensure secure internet communication.
The file includes information about the certificate recipient, the associated public key, and details about the certificate issuer.
A .cer file can be binary or Base64-encoded, adhering to the X.509 standard that dictates the format for public-key certificates.
It outlines structured content, specifying details like subject, issuer, public key, and validity period.
These files serve diverse purposes, including SSL/TLS for website security, code signing for software source verification, and validity period (start and expiration dates).
A .cer file is a digital certificate format that contains a certificate usually issued by a Certificate Authority (CA).
It is represented in base-64 ASCII encoding.
How to install a .CER certificate on a server
To install a .CER certificate on a server, the specific steps may vary depending on the server’s operating system and the software being used.
However, the general process typically involves the following steps:
Step 1: Import the Certificate:
- On a Windows server, you can import the certificate into the local computer store using the Certificate Import Wizard. This can be done by double-clicking the .CER file, clicking the “Install Certificate” button, and following the steps to complete the import process.
Step 2: Assign the Certificate to the Server:
- After importing the certificate, you may need to assign it to the appropriate service or application on the server. For example, in the case of a web server like Apache, you would need to configure the server to use the imported certificate for SSL/TLS encryption. This typically involves selecting the installed certificate from the server’s configuration settings.
Step 3: Restart the Server:
- In some cases, you may need to restart the server or the specific service/application to apply the changes and start using the newly installed certificate.
.PEM Certificate
On the other hand, a .PEM certificate is encoded in Base64.
This encoding method allows binary data to be represented as a string, making it safe for transmission through protocols that are designed to handle only ASCII characters.
The .PEM format is commonly used in various applications, including securing email and web communications.
A .PEM file can contain different types of data, such as end-entity certificates, private keys, or a complete chain of trust.
What are PEM certificates used for?
PEM certificates are used to store SSL certificates and their associated private keys.
They can contain the end-user certificate, intermediate certificates, and the root certificate, which form a full SSL chain.
These certificates are used for encrypting HTTPS in web servers like Nginx and Apache.
Additionally, PEM files can include other types of data, such as RSA keys used for SSH.
The PEM format is the most common format that Certificate Authorities issue certificates in, and it is a base64 encoded ASCII file that contains “—–BEGIN CERTIFICATE—–” and “—–END CERTIFICATE—–” markers.
How to install a .PEM certificate on a server
To install a .PEM certificate on a server, the specific steps may vary depending on the server’s operating system and the software being used. However, the general process typically involves the following steps:
Step 1: Create a .PEM file:
- To create a .PEM file, you need to concatenate the end-entity certificate, intermediate certificates, and the root certificate in the correct order. You can use a text editor to create the file and add the certificates in the correct order. The file should start with “—–BEGIN CERTIFICATE—–” and end with “—–END CERTIFICATE—–“.
Step 2: Copy the .PEM file to the server:
- Once you have created the .PEM file, you need to copy it to the server where you want to install the certificate. You can use a secure file transfer protocol like SFTP or SCP to transfer the file to the server.
Step 3: Configure the server to use the .PEM file:
- The specific steps for configuring the server to use the .PEM file can vary depending on the server software being used. For example, in Apache, you would need to modify the SSL configuration file to point to the .PEM file. In Nginx, you would need to specify the path to the .PEM file in the server configuration settings.
Step 4: Restart the server:
- In some cases, you may need to restart the server or the specific service/application to apply the changes and start using the newly installed certificate.
CER vs PEM Certificates: Key Differences
The key difference between the two lies in their encoding methods.
While .CER certificates are encoded in binary format, .PEM certificates are encoded in Base64, making them more versatile for different types of data and applications.
It’s also worth noting that the .CER extension is often associated with Windows, while .PEM is a more generic and widely used format.
Wrap!
In summary, the difference between .CER and .PEM certificates lies in their encoding and the type of data they can contain.
The .CER extension typically represents a binary X.509 certificate, while the .PEM extension is used to encode X.509 certificates in Base64, allowing for greater versatility in different applications.
To learn more about the differences between .CER and .PEM certificates, understand their encoding methods and the type of data they can contain.
This knowledge is crucial for effectively working with digital certificates in various IT and security contexts.
