TLS (Transport Layer Security)
Transport Layer Security (TLS) Overview
TLS is a widely used security protocol designed for ensuring privacy and data security in online communications.
Primarily encrypts communication between web applications and servers (e.g., web browsers and websites).
Other uses: Encrypting emails, messaging, and VoIP.
First introduced in 1999 by the Internet Engineering Task Force (IETF); latest version is TLS 1.3 (published in 2018).
TLS vs SSL
TLS evolved from the earlier SSL protocol (Secure Sockets Layer), developed by Netscape.
TLS 1.0 started as SSL 3.1, but was renamed before release to disassociate from Netscape.
TLS and SSL are often used interchangeably due to their close relationship.
TLS vs HTTPS
HTTPS is HTTP combined with TLS encryption.
Any website using HTTPS is utilizing TLS to encrypt communication.
Why Should Businesses Use TLS?
TLS encryption protects against data breaches and cyberattacks.
Major browsers (e.g., Google Chrome) warn users about non-HTTPS sites.
HTTPS padlock icon is a sign of a secure, TLS-protected connection.
TLS Components
Encryption: Hides transferred data from third parties.
Authentication: Verifies the identity of communicating parties.
Integrity: Ensures data has not been altered during transmission.
TLS Certificates
To use TLS, a website must have a TLS certificate (commonly referred to as an SSL certificate).
Issued by certificate authorities (CAs) to the domain owner.
Contains the domain’s ownership details and public key (used for encryption).
How TLS Works
TLS Handshake
The handshake process establishes a secure connection between the user's device (client) and the web server.
Specify TLS version: (e.g., TLS 1.0, 1.2, 1.3).
Choose cipher suites: Set of algorithms for encryption.
Server authentication: Verifies server’s identity using the TLS certificate.
Generate session keys: For encrypting messages after the handshake.
Public key cryptography: Uses a public key to decrypt data, while only the server’s private key can encrypt it.
After encryption and authentication, the data is signed with a Message Authentication Code (MAC) for integrity.
Performance Impact of TLS
Modern TLS versions (e.g., TLS 1.3) have minimal impact on web performance.
TLS False Start and Session Resumption mitigate potential latency by speeding up the handshake.
TLS 1.3 improves speed with a 1-round-trip handshake and zero round trips for previously connected users.
Implementing TLS
Cloudflare offers free TLS/SSL certificates.
Alternatively, businesses can acquire and install an SSL certificate from a certificate authority on their servers.
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