When two hosts communicate with each other over an unsecured network, and they want to transfer sensitive data between them, especially for bank transactions or e-commerce transactions, communication must be encrypted and secure enough. The SSL and TLS protocols are developed for that purpose. It ensures security for bank and e-commerce transactions over an unsecured network.

We often use the terms SSL and TLS interchangeably. But are they the same, or are they different? How are they different from each other? Let’s understand that in more detail.

SSL vs. TLS: How is TLS different from SSL?

SSL and TLS are two different protocols. There are seven main differences between SSL and TLS.

• To enable secure data communication between two hosts over an unsecured network, SSL was first developed by Netscape. SSL 2.0 was the first publicly released version of the protocol. But, soon security flaws were found in it. So, SSL 3.0 replaced SSL 2.0. TLS 1.0 is an upgraded version of SSL 3.0. So, overall TLS is an updated protocol of SSL.
• When two hosts communicate over TLS and the client has no certificate, the TLS client does not use a separate NoCertificate message to notify that. The client returns an empty certificate message. But in SSL, the client issues a NoCertificate message.
• SSL operates with SHA or MD5. But, TLS uses HMAC which can operate with any hash function.
• SSL uses RSA, Diffie-Hellman or Fortezza/DMS output to create key material. But TLS uses the HMAC standard and its pseudorandom output to do the same.
• In SSL, the CertificateVerify message requires complex procedures. But, in TLS, the verification message is included in the previous handshake message.
• In TLS, the pseudorandom function output or PRF output of the HMAC algorithm is used to generate a master secret. It uses the ‘client finished’ or ‘server finished’ designation to create the Finished message. But, in SSL, the same is created in an ad-hoc manner using a combination of hash output, selected cipher suite, and parameter information.
• SSL specifically uses RSA, Diffie-Hellman, or Fortezza/DMS cipher suites. But TLS has stopped Fortezza/DMS support.

So, to summarize, TLS is an upgraded and more secure version of SSL. Many security vulnerabilities are found in SSL. And so, it is advisable to use TLS.

Security Fundamentals Practice Tests

The Security Fundamentals Practice Tests test one’s fundamental knowledge of cyber security. The practice tests are good for those who are preparing for various certification exams like the CCNA, CCNP, or CompTIA. They are also good for students and IT/security professionals who want to improve their understanding of cybersecurity.