220-1102 Question 321
Single answerFencesA technician is securing a small office network after discovering that several employee PCs can still communicate with a decommissioned test VLAN that should be isolated. The office uses a virtualized environment to separate production and test systems. The technician recommends implementing a control that prevents devices in one network segment from accessing resources in another segment unless explicitly allowed. Which of the following BEST describes this control?
- A
A fence that creates a boundary between network segments to restrict communication
- B
A patch management policy that keeps test systems updated with the latest security fixes
- C
A backup rotation schedule that preserves copies of systems from both VLANs
- D
A file-level permission change that removes user access to shared folders
Show answer and explanation
Correct answer: A
Explanation
The best answer is the fence because the scenario is specifically about isolating one environment from another and allowing communication only when explicitly permitted. In A+ Core 2 objectives, fences are associated with boundary-based isolation and segmentation concepts used to limit exposure between systems, departments, or environments such as production and test networks. This aligns with security best practices that recommend network segmentation, least privilege, and limiting unnecessary lateral movement. Patching, backups, and file permissions are all valid security or operational controls, but they do not solve the specific problem of separating network segments and restricting inter-network access.
- A. Correct.
Correct. In A+ Core 2 security discussions, a fence refers to a logical or virtual boundary used to isolate systems or network segments from one another. In this scenario, the goal is segmentation and controlled communication between production and test environments, which is exactly what a fence is intended to provide.
- B. Incorrect.
Incorrect. Patch management improves system security by reducing vulnerabilities, but it does not create segmentation or prevent traffic between VLANs by itself. Someone might choose this because patching is a common security control, but it does not address isolation between environments.
- C. Incorrect.
Incorrect. Backups are important for recovery and business continuity, but they do not control live network communication between segments. This distractor is plausible because technicians often think broadly about infrastructure controls, but backup scheduling is unrelated to network isolation.
- D. Incorrect.
Incorrect. File permissions control access to specific data and shared resources, not communication paths between VLANs or isolated environments. A candidate might pick this if they confuse access control with network segmentation, but the issue described is at the network/environment boundary level.