A networking technician is working on the wireless network at a medical clinic. The technician accidentally sets up the wireless network so that patients can see the medical records data of other patients. Which of the four network characteristics has been violated in this situation?

• A. Fault tolerance
• B. Scalability
• C. Security
• D. Quality of Service

Answer: (C)

This situation highlights protecting data privacy and controlling who can access information. When patients can see other patients’ medical records, the network isn’t enforcing proper access controls or data isolation, which is a security failure. Security in networking covers authentication, authorization, encryption, and segmentation to prevent unauthorized disclosure of sensitive data. In a wireless environment, you’d want strong encryption, enterprise authentication, and clear separation of restricted data from guest access (for example, via VLANs and access control lists). If those controls are misconfigured or missing, confidential information is exposed, which violates security requirements and often regulatory rules like HIPAA. The other options address different concerns: fault tolerance is about remaining available during failures, scalability about handling growth, and Quality of Service about performance guarantees.