Engineering / advanced
Protect connections and protocol boundaries
Understand connection authentication and encrypted transport while keeping cryptographic primitives distinct from application authorization.
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Inside this module
Module 01 advanced
Protect connections and protocol boundaries
Understand connection authentication and encrypted transport while keeping cryptographic primitives distinct from application authorization.
- 01
TLS binds key establishment to a verified peer
Separate key agreement, transcript authentication, record protection, and application authorization in a certificate-authenticated TLS 1.3 connection.
25 min - 02
A signed certificate is only one part of validation
Evaluate trust anchors, certificate paths, validity intervals, constraints, usage, and the expected service name as distinct verification requirements.
26 min - 03
Forward secrecy limits what a later key theft reveals
Distinguish signing keys, ephemeral agreement secrets, traffic secrets, and resumption material when evaluating recorded traffic after a compromise.
26 min - 04
Resuming a session does not make early data fresh
Connect resumption PSKs, ticket lifetimes, 0-RTT replay risk, and application deduplication while keeping encryption distinct from exactly-once effects.
27 min - 05
Mutual TLS authenticates peers within an identity scope
Bind verified client certificates to workload principals and enforce action- and resource-specific authorization across service and proxy boundaries.
25 min - 06
Rotate credentials before the usable trust window closes
Plan issuance, trust overlap, rollout, verification, and revocation without assuming that replacing one certificate immediately changes every connection.
25 min - 07
Segmentation controls permitted connections at a boundary
Evaluate directional network policy, additive allow rules, enforcement prerequisites, and the separation between transport reachability and application authorization.
25 min - 08
Availability depends on the work accepted before rejection
Budget CPU, retained state, and downstream work under untrusted load while distinguishing bounded admission from unlimited queueing.
26 min - 09
Encrypted DNS changes who can observe a query
Separate resolver-channel confidentiality, resolver trust, DNSSEC validation, forwarding-cache behavior, and the limited separation offered by oblivious DNS.
25 min - 10
Test the rejection path as carefully as the happy path
Build an explicit TLS test matrix for names, trust, versions, fallback, and termination layers without mistaking diagnostic continuation or a clean sample for proof.
28 min