What Is TLS, How Does It Work? HTTPS, TLS and SSL

TLS (Transport Layer Security) is a protocol used to secure communication over a computer network. It basically provides secure communication by establishing an encrypted connection between two parties, a client (like a web browser) and a server (like a website).

TLS is used to protect sensitive information such as login credentials and financial transactions, as it prevents third parties from intercepting and accessing the transmitted data. It is also widely used to secure websites, e-mails, and other forms of online communication on the Internet.

TLS works using a combination of public-key encryption and symmetric-key encryption. When a client establishes a connection with a server, the server sends the client its public key, which the client uses to authenticate the server. The client then generates a unique session key that is encrypted using the server's public key and sent back to the server. The server uses its private key to decrypt the session key and establish an encrypted connection.

TLS is an evolution of the now-deprecated Secure Sockets Layer (SSL) protocol. However, the term "SSL" is still commonly used to refer to TLS. 
Here are some detailed statistics on what's good, what's bad, and what's irritating in the TLS world:

Currently just over two years old, TLS 1.3 has become the protocol of choice for 63 percent of the top one million web hosts on the Internet. However, support can vary greatly. In some countries like the United States and Canada, 80 percent of web servers choose it, while in other countries like China and Israel, only 15 percent of servers support it. 

Now 25 percent of certificates are signed with the Elliptic Curve Digital Signature Algorithm (ECDSA), and over 99 percent of servers choose non-RSA handshakes whenever possible. 

Despite the widespread adoption of TLS 1.3, legacy and vulnerable protocols are left active. RSA handshakes are allowed by 52 percent of web servers, SSL v3 is enabled on 2 percent of sites, and 2.5 percent of certificates have expired. 

TLS 1.0 and TLS 1.1 are now officially deprecated due to known security flaws. They've largely disappeared from use on the top one million sites, but few web servers, 0.4 percent, still choose one of them during an HTTPS connection. 

Encryption continues to be abused. The proportion of phishing sites using HTTPS and valid certificates rose to 83 percent, with roughly 80 percent of malicious sites coming from just 3.8 percent of hosting providers. 

Recent research has found that active SSLStrip attacks successfully steal user login credentials, indicating an increased need to use HTTP Strict Transport Security (HSTS) headers or disable HTTP services entirely. 

The near complete obsolescence of certificate revocation methods increases the desire to move towards extremely short-term certificates in the certificate authority (CA) and browser industries. 

The TLS fingerprint shows that 531 servers in the top one million potentially matched the identity of Trickbot malware servers, and 1,164 servers matched the Dridex server.

How TLS Works

Here are the steps on how TLS works:

• The client (like a web browser) establishes a connection with the server (like a website).

• The server sends the client a copy of the TLS certificate containing its public key, domain name, and information about the identity of the server, such as the certificate authority (CA) that issued the certificate.

• The client authenticates the server using the information in the TLS certificate and the server's public key.

• The client generates a unique session key, which is a randomly generated string of data that will be used to encrypt communication between the client and server.

• The client encrypts the session key using the server's public key and sends it back to the server.

• The server decrypts the session key using its private key and establishes an encrypted connection with the client.

• The client and server can now communicate securely over the encrypted connection, all data is encrypted and decrypted using the session key.

• TLS uses a combination of public-key cryptography and symmetric-key cryptography to provide secure communication. Public key encryption is used to authenticate the server and establish an encrypted connection, while symmetric key encryption is used to encrypt and decrypt the transmitted data.

Why Should You Care About TLS?

TLS is important for several reasons. Some of these reasons are as follows:

1. Protects sensitive information

TLS helps protect sensitive information such as login credentials and financial transactions by establishing an encrypted connection between a client (such as a web browser) and a server (such as a website). This prevents third parties from interfering with and accessing the transmitted data.

2. Increases security and privacy

TLS helps improve the security and privacy of online communication by establishing an encrypted connection. This is especially important for websites that handle sensitive information, such as online banking and e-commerce sites.

3. Increases trust and credibility

Websites that use TLS are more reliable because they are committed to security and privacy. This can be quite important for businesses looking to build trust with their customers.

4. Meets regulatory requirements

In some industries, the use of TLS is required by law or regulatory standards. For example, Payment Card Industry Data Security Standard (PCI DSS) requires websites that process credit card transactions to use TLS.
In summary, TLS is essential to protect sensitive information, increase security and privacy, and meet regulatory requirements. It is a crucial component of online security and is essential for anyone using the internet.

HTTPS vs. TLS vs. SSL

HTTPS, TLS and SSL are related technologies used to secure communication over the internet. 
HTTPS (Hypertext Transfer Protocol Secure) is a protocol for secure communication over the internet. It is based on the standard HTTP protocol, but adds an extra layer of security by encrypting data transmitted between a web server and a client (like a web browser). This helps protect against hackers who may try to intercept the transmitted data.

TLS (Transport Layer Security) is a protocol that provides secure communication over the internet. It is the successor to SSL (Secure Sockets Layer) and is designed to be more secure and efficient than SSL. Like SSL, TLS uses encryption to secure data transmitted between a server and a client.

SSL (Secure Sockets Layer) is a protocol widely used in the past to provide secure communication over the internet. But it has now been replaced by TLS, which is considered more secure. However, the term "SSL" is still commonly used to denote TLS and other technologies that provide secure communication over the Internet.

In general, HTTPS, TLS and SSL are important tools to ensure the security and privacy of communication over the Internet. They are used to prevent third parties from intercepting data transmitted by websites, e-mail servers and other internet-based services.

Top Q&A About TLS

1. What is the difference between TLS and SSL?

TLS is the successor to SSL. TLS is a newer and more secure version of SSL and is designed to be more efficient and effective at protecting against a variety of security threats. SSL is no longer considered a secure protocol and its use is not recommended.

2. Is TLS the same as HTTPS?

HTTPS (Secure Hypertext Transfer Protocol) is a protocol for secure communication over the internet. It is based on the standard HTTP protocol, but adds an extra layer of security by encrypting data transmitted between a web server and a client (like a web browser). HTTPS uses TLS (or SSL) to provide basic security for the connection.

3. Is it mandatory to use TLS?

TLS is not mandatory but recommended for any application or service that transmits sensitive data over the internet. TLS provides an important layer of security that helps protect against hackers who might try to intercept or tamper with the transmitted data.

4. What is a TLS certificate?

A TLS certificate is a digital certificate used to establish a secure connection using TLS. TLS certificates contain information about the identity of the certificate holder and are issued by a certificate authority (CA). When a client connects to a server using TLS, the server presents the TLS certificate to the client to establish a secure connection.

5. What is TLS handshake?

TLS handshake is the process of establishing a secure connection between a client and a server using TLS. During TLS handshake, the client and server exchange keys and certificates to establish a secure connection. 

6. How do I enable TLS on my server?

To enable TLS on a server, you must install a TLS certificate and configure your server software to use TLS. This process will vary depending on the specific server software you are using. 

7. What is the latest version of TLS?

Various versions of TLS have been released over the years, and each release brings new features and improvements. The latest version of TLS is TLS 1.3, which was released in 2018.

8. Is TLS 1.3 faster than previous TLS versions?

Yes, TLS 1.3 is generally faster than previous TLS versions. TLS 1.3 includes several performance improvements that make it faster and more efficient than previous versions. These improvements include reduced overhead, faster handshakes, and the ability to use 0-RTT (zero round-trip time) data to speed up the connection establishment process.