If you use a screen reader, you might have heard it say “secure connection” or read out “HTTPS” when visiting a website. But what does that really mean? It means the website is using something called Transport Layer Security (TLS) to keep your information safe. TLS protects your passwords, personal messages, and payment details from hackers while you browse, shop, or send emails online. In this blog, we’ll explain TLS in the easiest way, so you can understand how it helps keep your online activity private and secure.
What is TLS?
Transport Layer Security (TLS) is a cryptographic protocol designed to provide secure communication over the internet. It ensures that data transmitted between a user’s device and a website, email server, or messaging app remains private and protected from eavesdropping, tampering, and impersonation. TLS is the successor to Secure Sockets Layer (SSL) and is widely used to secure web browsing, emails, online payments, and other digital communications.
Difference Between TLS and SSL
SSL (Secure Sockets Layer) and TLS (Transport Layer Security) are both methods used to keep information safe when it’s sent over the internet. SSL is the older version and is not considered secure anymore, while TLS is the newer, stronger, and safer version that is used on most websites today. TLS offers better protection, faster performance, and regular updates, unlike SSL which is outdated and no longer supported. Even though people still use the term “SSL,” what they usually mean is TLS. In simple terms, TLS is just an improved and more secure version of SSL that helps keep your online data safe from hackers.
How Does TLS Work?
TLS secures communication through three main steps:
1. Handshake Process
When you visit a secure website (e.g., https://example.com), your browser and the website’s server perform a TLS handshake to establish a secure connection. During this process, the server presents a TLS certificate to prove its identity, helping the browser verify that it is connecting to the correct and trusted website. Both the browser and the server then agree on the encryption method they will use for secure communication. Finally, they generate and exchange encryption keys, which will be used to protect the data transferred during the session.
2. Encryption
Once the handshake is complete, TLS encrypts all data exchanged between your device and the website. This means that even if a hacker intercepts the communication, they will only see scrambled, unreadable data. TLS uses advanced cryptographic algorithms to ensure that sensitive information, such as login credentials, credit card details, and personal messages, remains confidential and secure.
3. Data Integrity
TLS also ensures that the data sent and received has not been altered during transmission. If an attacker tries to modify the data, TLS detects the tampering and immediately terminates the connection to prevent the use of corrupted or manipulated information. This guarantees that the data reaching your device is exactly what the server intended to send, preserving the integrity and reliability of online communications.
TLS Certificates & HTTPS
Websites that use TLS have TLS certificates, which are issued by trusted organizations known as Certificate Authorities (CAs). These certificates serve as digital proof that a website is authentic and not a fraudulent or phishing site. When you visit a website with a valid TLS certificate, your browser verifies the certificate’s authenticity before establishing a secure connection. This process helps prevent cybercriminals from impersonating legitimate websites to steal user information, such as login credentials and financial details.
TLS Certificates and Their Role
TLS certificates contain essential information, including the website’s domain name, the organization’s details, the issuing Certificate Authority, and the certificate’s expiration date. When a user connects to a TLS-enabled website, the browser checks the certificate against a trusted list of CAs. If the certificate is valid and issued by a recognized authority, the browser proceeds with establishing a secure connection. If the certificate is expired, self-signed, or issued by an untrusted CA, the browser displays a security warning to the user.
What is HTTPS?
Websites that use TLS display “HTTPS” (instead of just “HTTP”) in their web address. The “S” in HTTPS stands for “Secure,” indicating that the website is protected by TLS encryption. HTTPS ensures that all data exchanged between the user’s browser and the website is encrypted, preventing hackers from intercepting sensitive information. Websites that handle login details, online payments, or personal data must use HTTPS to maintain security and user trust.
Types of TLS Certificates
1. DV (Domain Validation)
Domain Validation (DV) certificates provide basic security and are the easiest to obtain. They only verify that the applicant owns the domain name by responding to an email or adding a DNS record. These certificates are ideal for personal websites, blogs, or small projects where encryption is needed, but identity verification is not a priority.
2. OV (Organization Validation)
Organization Validation (OV) certificates offer a higher level of security by verifying both the domain ownership and the legitimacy of the organization behind the website. The issuing Certificate Authority (CA) conducts a background check on the business before issuing the certificate. OV certificates are commonly used by businesses and organizations to build trust with users by proving their authenticity.
3. EV (Extended Validation)
Extended Validation (EV) certificates provide the highest level of security and credibility. They require a rigorous verification process, including legal and operational checks of the business. Websites with EV certificates display the company’s name in the browser’s address bar, providing a clear indicator of trust and legitimacy. These certificates are commonly used by financial institutions, e-commerce sites, and government websites where security and user confidence are critical.
Common TLS Attacks & How to Stay Safe
Even though TLS is designed to be secure, hackers have discovered ways to exploit vulnerabilities in older versions. Here are some common TLS attacks and how to protect against them:
1. Downgrade Attacks (POODLE, BEAST)
In a downgrade attack, hackers trick a server or browser into using an older, weaker version of TLS or SSL instead of the latest secure version. This makes it easier for attackers to break encryption and steal sensitive data. For example, the POODLE attack exploits SSL 3.0, while BEAST targets weaknesses in older TLS versions.
🔹 Solution: Always use the latest TLS version (TLS 1.3) and configure servers to reject outdated protocols like SSL 3.0 and TLS 1.0.
2. Man-in-the-Middle (MITM) Attacks
In a MITM attack, a hacker intercepts your communication with a website, acting as a middleman between you and the real website. This allows them to steal login credentials, payment details, or manipulate the data you send and receive. MITM attacks are especially dangerous on public Wi-Fi networks where encryption may be weak.
🔹 Solution: Always check for “HTTPS” in the browser’s address bar before entering sensitive information. Avoid using public Wi-Fi for online banking or shopping unless connected through a VPN.
3. Weak Cipher Suites
TLS uses encryption methods known as cipher suites to protect data. However, some older cipher suites have security flaws that hackers can exploit to decrypt sensitive information. If a website supports weak cipher suites, it may be vulnerable to attacks such as Logjam or FREAK, which allow attackers to downgrade encryption strength.
🔹 Solution: Website administrators should disable outdated cipher suites and configure servers to use only strong encryption algorithms, such as AES-GCM and ChaCha20.
Common Application of TLS
Transport Layer Security (TLS) is widely used to secure communication over the internet. It’s most commonly seen in HTTPS, which encrypts the connection between websites and users to protect sensitive data like passwords and payments. TLS also secures email transmission through protocols like SMTP, IMAP, and POP3 using STARTTLS. Messaging apps such as WhatsApp and Signal use TLS to encrypt chats, while VPNs like OpenVPN rely on it to protect online activity, especially on public networks. File transfers via FTPS, cloud services like Google Drive and AWS, and mobile apps handling logins or transactions also use TLS to ensure data privacy. Overall, TLS plays a key role in keeping digital communication safe and secure.
Versions of TLS
TLS, or Transport Layer Security, has different versions that have improved over time to make internet communication more secure. The first version, TLS 1.0, came out in 1999 but is now outdated and not considered safe. TLS 1.1 followed in 2006 with small improvements, but it too is no longer secure. TLS 1.2, released in 2008, became widely used and is still considered safe today for most uses. The latest version, TLS 1.3, came out in 2018 and is faster, more secure, and removes older, weaker features. Most modern websites and apps now use TLS 1.2 or TLS 1.3 to protect your data during online communication.
How to Understand Websites are TLS Authenticated?
When you visit a website, the easiest way to check if it is TLS authenticated is by looking at the address bar in your web browser. A secure website will begin with “https” instead of just “http.” You will also notice a small padlock icon before the website address. This means the site is using TLS encryption to protect your data while it’s being transmitted. If the website only shows “http” and does not have a padlock, it may not be secure.
You can click on the padlock icon to get more details about the website’s security. When you click it, a small window will open, showing that the connection is secure. It also shows information about the security certificate, such as who issued it and whether it is valid. Some browsers even show which version of TLS is being used, like TLS 1.2 or TLS 1.3. This helps confirm that the website is properly protected and trusted.
If you want a deeper check, you can use free online tools to test the website’s security. For example, by visiting websites like SSL Labs or Why No Padlock, you can enter the website link, and the tool will tell you if the TLS certificate is valid. These tools also show which encryption methods are being used and whether there are any weaknesses. This method is helpful for users who want extra confidence before entering sensitive information on a website.
Conclusion
In simple words, TLS helps keep your online information safe and private when you visit websites, send emails, or use apps. It works in the background to protect your passwords, payments, and messages from hackers. Always look for “https” at the beginning of the website link and make sure the connection is secure. If you use a screen reader, it will read out “https” or “secure connection” in the address bar, which means the website is protected. By using updated browsers and being careful on the internet, you can enjoy safe and secure browsing every day.