An uptick in cyber attacks and greater awareness about government surveillance have prompted calls for tighter security on the Internet, and a big part of that is encrypting  the traffic that flows to and from websites.
Google, Facebook, and Microsoft are among the many companies that have been pushing for wider use of SSL/TLS (Secure Sockets Layer/Transport Layer Security) encryption, though it can be tricky and expensive to implement. Here’s the basics of what you need to know.
What is SSL/TLS?
It’s a protocol originally developed in part by Netscape in the 1990s, to ensure the authenticity of websites and allow data to be exchanged securely with end users.
It creates an encrypted connection using public key cryptography, typically indicated by “https” and a padlock appearing in the URL window of a browser.
Why is it important?
Data exchanged using only http can be intercepted by hackers.

Data can be collected or tampered with, creating privacy and security risks for users. Nearly all reputable banks and e-commerce sites use SSL/TLS these days, but many smaller websites still do not.
Is it hard to set up?
SSL/TLS is known to be finicky and difficult to implement, especially for very large websites. Organizations known as Certification Authorities (CAs) sell different types of digital certificates used for authenticating websites.

Depending on the type of certificate, CAs will verify that the entity requesting one is legitimate, to guard against fraudulent sites.

But the certificates can be expensive, and critics say the cost and complexity are off-putting.

Certificates also expire, and it’s important that IT admins know when they have to be renewed.
Are there any weaknesses?
In short, many.

Cyber security experts have devised numerous attacks over the years that compromised SSL/TLS connections.

Also, software vulnerabilities such as Heartbleed have been found in OpenSSL, a widely used SSL application. CAs have occasionally been hacked, with attackers creating certificates for websites that are used for phishing.
In a 2011, cryptographer Moxie Marlinspike outlined the many weaknesses in the CA system and the complexities of finding a replacement. “It’s amazing that SSL has endured for as long as it has in contrast to a number of other protocols from the same vintage,” Marlinspike wrote. More than 600 CAs issue or sell SSL/TLS certificates; some of the larger players include Verisign and Comodo. 
What’s being done about the problems?
A project called Let’s Encrypt, launched last year, issues free, domain-validated digital certificates as part of a movement to spur wider use of encryption on the web.

Bugs in SSL/TLS are patched when new attacks are discovered, but there’s not really a viable replacement for the whole system at this point.

Changing it would require agreement from the whole industry, and that’s unlikely anytime soon.

For now, protecting private SSL/TLS keys is probably the most important task, and a variety of hardware security modules on the market can securely manage those digital keys.