CCNA Exam Preparation / Security fundamentals
CCNA technique 170: Standard ACL placement — practice and verify
An original CCNA exercise on standard acl placement with predictions, evidence, and a changed-condition check.
Environment and inputs: CCNA 200-301 v1.1 study; isolated Cisco IOS / IOS XE lab or paper exercise where applicable.
Practice task
Draw one source accessing two destinations and show how an early source-only deny could block both.
Expected reasoning
A standard IPv4 ACL matches source addresses; placement must account for destinations it cannot distinguish.
Produce evidence
Use an isolated simulator, approved lab or paper trace. Record the topology, prediction and observed result. Before device changes, capture the relevant interface, route, neighbor or service state. Ping alone may not prove the behavior under study.
Introduce a counterexample
Change one condition in the standard acl placement exercise and predict the result before checking it. Explain which observation would disprove your hypothesis. Restore the baseline, repeat from blank notes and keep both results.
Exam scope
Independent CCNA 200-301 v1.1 exercise, checked against Cisco resources on 2 November 2026. It is not a recalled exam question. The collection’s 200 techniques do not represent exam question counts or weights. Check Cisco’s current exam rules and your simulator’s supported syntax.