In this blog post, we will discuss important SSL interview questions that you will be asked by your employer to assess your knowledge and understanding of the importance of using a secure connection. These questions are designed for technical positions in web development or security but they may be valuable for any position where it is critical to have an accurate understanding of how SSL works.
1. What is SSL?
Ans. SSL is the abbreviation for Secure Sockets Layer, which is a protocol used in building an encrypted link between a web server and browsers. It’s considered the most important security protocol on the internet because it ensures that communication between users and web servers cannot be intercepted or decoded by third parties.
SSL is built on top of TCP/IP which offers two-way data transmission over a single connection. SSL uses public-key cryptography which allows two people to communicate securely without having to exchange secret keys beforehand.
2. Who invented SSL?
Ans. The SSL protocol was invented in 1994 by Netscape Communications Corporation. It has gone through multiple changes since then to remain secure and up-to-date with modern encryption standards, but its basic functions remain unchanged: establishing a private connection that ensures data being transferred is both safe and authentic.
3. Why do you need SSL Certificates?
Ans. The certificate provides people with assurance that the website they’re browsing, shopping on, or entering personal information on is really from whom it claims to be from. It also provides people with assurances that their information will not be intercepted or stolen by third parties.
4. Where are the SSL’s used?
Ans. These certificates are used in various forms like email servers, websites, and cell phones as well as other applications in order to guarantee secure communications between different parties without revealing their content to any third party.
5. What is Encryption?
Ans. Encryption is the process of transforming information into an unreadable format so that only those who have access to a decryption key can read it. In SSL encryption, the two main components are private keys and public keys. Private keys are used to encrypt the data, while public keys are used to decrypt it.
6. How does SSL work?
Ans. The SSL is a security protocol that encrypts data before it travels the Internet. The data traveling through an SSL-secured connection is always assigned a key, which verifies its authenticity and protection.
The SSL connection can be established by either the client (user) or server (website). When the server begins to send encrypted data, it sends its public key to the client. The client then uses this key to encrypt all subsequent data in order to ensure that no one else intercepts any of the information.
7. What is CSR?
Ans. A certificate signing request (CSR) is a sequence of characters, created within an application and then passed to the server for verification.
A CSR contains three sections: the public key, the private key, and a signature. The public key and private key are used to generate a cryptographic signature that is included with the CSR.
A CSR can be generated by an application or within the server configuration. Different types of applications will have different options for generating a CSR.
8. What are the risks of not using SSL?
Ans. If you don’t use SSL, your files are transferred in plain text. Unprotected data carries a high risk of being stolen by malicious agents on public networks, including ISPs and many other entities that can see what’s passing over the network.
9. What is a CA and why do they matter?
Ans. CA’s are the organizations you trust to validate your identity when visiting a website or receiving an email. The most common way to do this is via TLS/SSL, in which case the CA embeds their public key into your browser (and/or operating system) of choice, and issues certificates for each of the websites you visit their own public key. In that case, an attacker cannot impersonate a website, therefore allowing you to safely browse and access your information on a said web server.
10. How can I tell if my site is secure with SSL or not?
Ans. The easiest way to tell is by looking at your address bar. If the URL starts with “HTTPS://” then you are on a secure site. If it’s just HTTP://, then you’re not.
11. What if I have an SSL certificate but my browser says the connection is insecure?
Ans. If your browser says the connection is insecure then you don’t have an SSL certificate installed.
12. what is an extended validation certificate?
Ans. extended validation certification is a high level of SSL/TLS certificate that requires extensive identity verification and business authorization. this certificate works like SSL or TLS just like your cybercafe or personal area network operates, verifying the ownership of domain name while establishing a confidential connection between a web server and internet user’s computer. unlike normal domain-based certificates, an EV security certificate must be authorized by a unique body called ‘Let’s Encrypt’, which is not endorsed by any federal or state government agency.
13. what is an SSL handshake?
Ans. The SSL handshake is a process that occurs when someone wants to set up an encrypted connection with another server using the Secure Sockets Layer protocol. This includes agreeing on encryption methods, exchanging encryption keys, and then authenticating their identity so they can start sending data back and forth securely.
14. what is DES?
Ans. The Data Encryption Standard (DES) is a symmetric encryption algorithm that was created by IBM in the 1970s. It’s been replaced by more modern algorithms like AES, and when it came out there were concerns about its strength; however, at this point, DES is considered to be outdated but still safe enough to use for most purposes.
15. What is ECC?
Ans. Elliptic Curve Cryptography (ECC) uses a different mathematical approach to encrypting data than DES does. It’s newer, so there haven’t been as many studies done on its security; however, it is generally considered more secure and efficient than DES.
16. What is an Open SSL?
Ans. OpenSSL is a software library to be used in applications that need to secure communications over computer networks against eavesdropping or need to ascertain the identity of the party at the other end. It has found wide use in internet web servers, serving a majority of all websites.
17. What is TLS?
Ans. TLS stands for “Transport Layer Security” and is a cryptographic protocol that provides privacy and data integrity between two communicating applications. It’s the successor to SSL (Secure Sockets Layer).
18. What is a Wildcard SSL?
Ans. A wildcard SSL is a type of SSL certificate that allows an encrypted connection to any domain in the server’s specified Common Name (CN) or DNS name. This means that you can protect all your subdomains and be able to issue it from a single Certificate Authority (CA).
19. What is SMTP?
Ans. The SMTP (Simple Mail Transfer Protocol) protocol is specified in RFC 821. It is the standard for sending email messages to an SMTP server for final delivery to a user’s mailbox or inbox. The sender may then use other protocols like IMAP (RFC 3501) or POP3 (RFC 1939) to retrieve these messages once the SMTP server has delivered them to the recipient’s email box.
20.What is SNI?
Ans. SNI (Server Name Indication) is an extension to the TLS protocol, which allows a server to present multiple certificates on the same IP address and TCP port. In other words, SNI enables a server to serve multiple name-based virtual servers over HTTPS on a single IP address & SSL/TLS port.