Stage 2 · Lesson 5 of 8
TLS and certificates
encrypts traffic and proves the server is who it claims to be. It is what puts the S in . This is encryption in transit: data is scrambled while it travels, so nobody in between can read it.
The server shows a certificate for its domain. A certificate authority, an organisation the browser already trusts, has signed it. The two sides then agree on keys during a short handshake.
Let's Encrypt issues free certificates that last 90 days. The certbot tool requests and renews them automatically, usually by proving you control the domain over HTTP or DNS. You will handle TLS at now, and at a or later.
Inspect a certificate with openssl s_client or curl -v to see its names, issuer and expiry date.
Common traprenewal: an expired certificate takes a whole site down, so automate renewal and alert well before expiry.
A question to check yourself, an AI practice session and 2 cheat sheet entries come with the full roadmap. Unlock
Resources for this stage
Start with
- VideoFreeComputer Networking: A Top-Down Approach (Video Lectures)
Jim Kurose and Keith Ross · Intermediate
Free lectures from the textbook authors; chapters 1 to 4 cover what DevOps needs
Practise
Keep handy
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- Load Balancer vs. Reverse Proxy vs. API Gateway: Demystifying Web Architectures (opens in a new tab)Read
Separates three components people often mix up, and what each one is for