TLS (Transport Layer Security) incorporates several protocols that work together to establish secure communication channels over the internet. The primary TLS protocols include:
- Handshake Protocol: This protocol is used to negotiate cryptographic algorithms, authenticate the server (and sometimes the client), and establish session keys for secure communication.
- Record Protocol: The record protocol is responsible for encapsulating higher-level protocol data (such as HTTP, FTP, etc.) into TLS records, encrypting these records using negotiated encryption algorithms, and ensuring their integrity through message authentication codes (MACs).
- Change Cipher Spec Protocol: This simple protocol signals transitions in encryption state during a TLS session. It communicates the readiness of both client and server to begin using the negotiated encryption parameters for secure data transmission.
- Alert Protocol: The alert protocol handles error messages and alerts generated by either the client or server during a TLS session. It notifies the peer about abnormal conditions or potential security threats, allowing both parties to take appropriate actions.
TLS operates primarily at the transport layer (Layer 4) of the OSI model. It secures data transmitted over TCP/IP networks by providing encryption, integrity, and authentication mechanisms. While TLS does not replace or modify the transport layer itself, it functions as a secure layer above it, ensuring that data exchanged between endpoints remains confidential and protected from unauthorized access.
TLS does not have distinct “sub protocols” in the traditional sense. Instead, it comprises the handshake, record, change cipher spec, and alert protocols, each serving specific functions within the TLS framework to establish and maintain secure connections.
TLS 1.2 (Transport Layer Security version 1.2) is a widely adopted version of the TLS protocol. It enhances security features compared to earlier versions by supporting stronger cryptographic algorithms, improving encryption mechanisms, and addressing vulnerabilities found in previous iterations. TLS 1.2 remains prevalent in secure web communication and is supported by most modern web browsers and servers. It ensures robust protection for sensitive data transmitted over the internet, maintaining the confidentiality, integrity, and authenticity of communications between clients and servers.