Ethernet and Switching

Access and Trunk Ports

Learn how access ports and 802.1Q trunk ports classify, carry, tag, and restrict VLAN traffic.

Intermediate15 min read
Ethernet and Switching lessonNetworkingPractice

UNTIMED COACHING

Practice before the pressure

Use feedback to correct the model, not merely memorize an option position.

GUIDED PRACTICE

Practice the lesson questions

Answer normal lesson questions without a timer. Every answer includes an explanation, and incorrect answers can be tried again before continuing.

CONCEPT MODELS

See the lesson as a system

Use these visual guides to connect the key ideas before answering the questions.

How an 802.1Q Trunk Identifies TrafficA trunk uses one native VLAN for untagged traffic and tags traffic for other VLANs.
How an 802.1Q Trunk Identifies TrafficTraffic enters a trunk framing decision and leaves either untagged for the native VLAN or tagged for another VLAN.
VLAN trafficBelongs to one VLAN
Compare with native VLANChecks against the native VLAN
Untagged frameCarries native VLAN traffic
Tagged frameCarries other VLAN traffic
Validating Untagged Trunk TrafficBoth ends need the same native VLAN, and the intended VLAN must also be available.
Validating Untagged Trunk TrafficA trunk review compares native VLAN settings, checks allowed membership, and verifies VLAN availability.
Trunk end AHas a native VLAN setting
Trunk end BMust interpret untagged traffic
Matching native VLANAligns untagged traffic handling
VLAN availabilityRequires the VLAN on the trunk