From encrypting the messages to identifying the Revoked certificates, X 509 Certificates plays a vital role in it. They are also the digital Certificates that are based on ITU (International Telecommunication Union) and include the PKI (Public Key Infrastructure) too.
While networking through a wide range of servers, X 509 Certificates act as a security guard and provide security to all the connections and communication that takes place on the internet. X 509 certificates are also an integral part of the SSL/TLS too. Before diving deep into the working and importance of the X 509 Certificate, let’s get an idea of a few terms.
CRLS – Certificate Revocation Lists are the list of digital certificates that are cancelled or revoked by the CA (Certificate authorities). It means that they cannot be trusted by the client who is seeking a secure connection with the webserver. SSL/ TLS Certificate – Secure Socket Layer/ Transport Layer Security is the certificate required by websites as proof of their legitimacy and has secure connections between web browsers and web servers. Cryptography provides us security while communicating by encrypting our data in a format that could be only accessible to decrypt by the recipient. When HTTPS – Hypertext Transfer Protocol Secure, and SSL/ TLS are combined they provide secure communication between the client (web browser) and the webserver.
Public key – It is a key that is used by the sender to encrypt the contents of the message so that it could only be decrypted by the recipient. Private Key – It is a key that is available to the recipient so that he/she can decrypt the data received from the sender.
Now, X 509 Certificates uses the combination of both the private and public keys. Both keys are used to cipher and decipher the contents of the data, guaranteeing their identity’s knowledge to the respective key holders and therefore providing security to the message. It also provides secure internet browsing by being part of the SSL/TLS in HTTPS. It’s not only the part of SSL/TLS or CRLS but also extends its application security to Digital Signatures.
Standard Information about X 509 Certificate
– It contains the version of the certificate that informs the kind of data the Certificate will contain. The version is X 509
– Secondly, it contains the serial number of the certificate.
– It also includes the name of the Certificate Authority that has issued the certificate.
– It has the information about the time and date up to which the certificate is valid.
– It contains the name of the customer who asked for the certificate.
– Lastly, it contains information about the algorithm used and the information of the ‘Public Key’ assigned to the owner.
Additionally, the X 509 version contains three outlined extensions, to support the consumers dilated ways of using this certificate, those extensions are used in two different ways stated below:
Different Identities Extension: This Extension helps in increasing the number of identities associated with the Public Key of the certificate. This increase in subjects could range from domain names, email addresses to IP addresses. For this purpose “Multiple-Domain Certificate” is made available by the Certificate authorities.
Limitation of Key Usage: The ‘key usage’ limits the extent of its usage that is the purpose of the key is limited.
Working of the X 509 Certificate
As discussed earlier, these certificate uses a combination of public and private key. Their data structure is basically dependent on the interface description language called ‘Abstract Syntax Notation One’ also known as ‘ASN.1’.
Its working principle is based on Public Key Infrastructure (PKI). So, the algorithms that work under this infrastructure to generate a public key are RSA (Rivest-Shamir-Adleman), ECC (Elliptic curve Cryptography), DSA (Digital Signature Algorithm). Now, let’s know how actually these algorithm works.
– There is a series of numerals that is used to encrypt the provided data.
– Now this encrypted message is sent to the recipient and it could only be decrypted with the private key that is provided to the recipient.
– That private key is also the set of random numerals.
– Public keys are made by employing a complicated cryptographical algorithm
– Every public key has an associated private key.
– The amount of protection provided is directly proportional to the length of the public key.
– There are encoding schemes like DER and PEM that are used to handle the storage of the data in the Certificates.
Applications of X 509 certificate (based on PKI Infrastructure)
Digital Signatures
Digital Signatures or electronic Signatures are required to be authenticated and encrypted to avoid any intrusion of the traducers and this is done using these certificates. These certificates prevent the plagiarism of the signatures by creating a certain numeral value through the algorithm.
SSL/TLS Certificate
These certificates are important for authenticated internet browsing. Without them, you will fail to provide an encrypted connection between your web server and the client. Due to this Clients might be hesitant in connecting with your web server. The base of these certificates is the PKI infrastructure.
Secure Shell (SSH)
They are a kind of X 509 Certificate that allows you to securely have access to the Credentials in SSH. This protocol prevents unauthorized access and suspicious attacks while transferring the files, forming a network. This protocol has also proved to be beneficial in cloud services and configuration administration tools.
Authentication of Digital Identity
The X 509 Certificate has proved to be a better option for the authentication of digital identities while forming any connection during different networks or servers or authenticating the identities in the public and private clouds.
How to Buy X 509 Certificate?
X 509 Certificate can be bought from any of the legitimate Certificate Authority. Before Buying do a good search about the Certificate authority and know if that authority is safe and secure. Make sure that the Certificate Authority is providing the Keys (That is public and Private keys) and also that these keys are authenticated and cannot be affected by any malicious attacks.
Lastly, there are a number of Certificate Authorities that could provide you the X 509 Certificates like GoDaddy, DigiCert, Sectigo, CACert, etc.
