Question

you manage a network that uses a single switch. all ports within your building connect through that switch.

in the lobby, there are also three rj45 ports connected to the switch. you want to allow visitors to plug in to these ports to gain internet access, but they should not have access to any other devices on your private network. employees connected throughout the rest of your building should have both private and internet access.

which feature should you implement?

a spanning tree
b vlans
c poe
d port authentication

Explanation:

Analyze the network requirements

The goal is to isolate visitor traffic on specific lobby ports from the internal private network while still allowing both groups to access the internet. This requires logical segmentation of a single physical switch.

Evaluate the options

Using the VLAN Segmentation and Network Isolation knowledge points

• Spanning Tree Protocol (STP) prevents loops in redundant network topologies but does not segment traffic.
• VLANs (Virtual Local Area Networks) segment a single physical switch into multiple logical networks, isolating visitor traffic from the private network.
• PoE (Power over Ethernet) delivers electrical power over network cabling and does not handle traffic isolation.
• Port authentication (802.1X) controls network access based on credentials but does not inherently segment the traffic paths for authorized guests versus employees on a single switch without VLAN assignment.

Therefore, implementing VLANs is the correct feature to achieve this isolation.

Answer:

• A Spanning Tree
• B VLANs (Correct answer)
• C PoE
• D Port authentication