Published Jul 26, 2021Updated Jul 31, 2023
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Secure Socket Layer (SSL) is a cryptographic protocol for securing computer networks.

Note: SSL was deprecated in 1999 and renamed Transport Layer Security (TLS) by the Internet Engineering Task Force. TLS is essentially an improved version of SSL (it is SSL 3.1) and features a number of improvements that address security concerns that were discovered in the initial and prior implementations of SSL.

SSL uses a cryptographic mechanism featuring a public and private key to encrypt data communicating over internet networks. SSL uses a protocol known as a ‘handshake’ to determine the authenticity of a server. The main advantage of SSL is the confidence it gives to users that a server has been authenticated by a trusted Certificate Authority (CA). Valid SSL certs can only be issued by accredited Certificate Authorities which have rigid standards for issuing them.

SSL validation can be instantly recognized on the web by seeing a green padlock in the url portion of a browser, in addition to traffic going over HTTPS.

These days Google ranks pages higher due to SSL cert verification and many browsers outright discourage or prevent their users from viewing sites that are lacking TLS/SSL validation.

Benefits of SSL include

  • E-commerce trust: Users who see a green padlock on e-commerce sites are more likely to go through with the transaction because they trust that the site is secure.
  • It gives users peace of mind that the website is handling data with integrity and that data has not been tampered as its being transferred between networks.
  • Encryption of data so that it is not viewable as plain text when being transferred.

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