Secure Communication Protocols in System Design
Learn how protocols like TLS and HTTPS establish secure communication channels to protect data in System Design.
Every time our system sends or receives information, whether through an API call, a database query, or a message between services, it’s crossing potentially unsafe networks.
It’s a common concern for developers building any system that handles information over a network. Without the right protections, that data is exposed to anyone who might be listening. Secure communication protocols are a non-negotiable part of modern System Design, as they establish trust between systems.
This lesson will walk us through the essentials of securing data in transit. This will help us understand the what, how, and why behind building secure communication channels.
Importance of secure communication in System Design
Modern System Design should build security from the start and treat it as a core part of the architecture.
When data travels across a network, it moves through various routers and servers. None of these may be under our control. This journey makes it vulnerable. Secure communication is the practice of protecting this
Protocols like Transport Layer Security (TLS) and its most common use case, HTTPS, form the foundation of secure online communication. TLS upholds three critical properties: confidentiality, integrity, and authenticity, ensuring that data remains private, unaltered, and exchanged between verified parties.
Note: The fourth pillar of security, availability, is maintained through separate resilience and reliability mechanisms, as discussed in the previous lesson.
Without these guarantees, systems are exposed to significant risks, including eavesdropping (the unauthorized interception of data), data tampering (the modification of data in transit), and identity spoofing (the impersonation of another system).
These threats can lead to compromised user accounts, data breaches, and a complete loss of trust in our service.
Integrating robust security measures is a fundamental requirement for building resilient and trustworthy systems. The visual below illustrates the difference between an unprotected and a protected communication channel. It also highlights where attackers can strike.
Understanding this difference is the first step. The next section explains the mechanisms that enable secure communication.
How TLS and HTTPS establish secure channels
Transport Layer Security (TLS) is a cryptographic protocol that provides secure communication over computer networks.
It is often used with the Hypertext Transfer Protocol (HTTP) to create HTTPS. HTTPS is the secure version of HTTP. While HTTPS operates at the application layer, TLS works just below it, securing the connection before any application data is sent.
The process of establishing a secure TLS channel is known as the TLS handshake.
This is a carefully choreographed ...