SSH vs. SSL/TLS: What’s The Difference?

SSH and SSL/TLS are both widely used cryptographic protocols for establishing secure connections and ensuring secure communication between two parties over an unsecured network. While they offer similar benefits such as authentication, encryption, and data integrity, they are designed for different use cases and have distinct features. Here is a detailed look into how they operate, their purposes, and their differences.

SSL stands for Secure Sockets Layer, while TLS stands for Transport Layer Security. SSL, the older version of the protocol, was deprecated in 2015, with most modern browsers no longer supporting it. TLS is the current, updated version of SSL, but the two terms are often used interchangeably out of habit. SSL/TLS is a PKI-based security protocol used to secure web traffic between a client and a server, primarily associated with HTTPS for securing browser-server communications.

SSL/TLS enables the web browser to authenticate the web server, encrypting data in transit to ensure confidentiality and integrity. Websites are expected to have a valid SSL/TLS certificate signed by a trusted Certificate Authority (CA) to prove legitimacy to users. Browsers warn users against accessing websites without a valid certificate. SSL/TLS is also used for securing other web communications like emails and VoIP calls.

On the other hand, SSH, which stands for Secure Shell, is a cryptographic network protocol used for secure remote access to systems and servers over untrusted networks. It provides mutual authentication between a client and a server and establishes an encrypted communication channel between them for a variety of use cases, including remote system access, command execution, software updates, file transfers, and managing network infrastructure.

The SSL/TLS handshake process involves the browser and server exchanging messages to authenticate the server, establish a session key, and verify the client’s identity. In comparison, the SSH handshake process includes server verification, session key generation, and client authentication using encrypted passwords or SSH keys.

In terms of application and security level, SSH is best suited for highly secure remote access to servers and devices, while SSL/TLS is effective in securing browser-server communications and other web traffic. Both protocols play crucial roles in ensuring secure communication over unsecured networks, each with its specific use cases and features.



Source link