The most likely way a rogue device was able to connect to the network is through a MAC cloning attack. In this attack, a personal device copies the MAC address of an authorized device, bypassing the 802.1X access control that relies on known hardware addresses for network access. The matching MAC addresses in the audit report suggest that this technique was used to gain unauthorized network access.
References =
* CompTIA Security+ SY0-701 Course Content: Domain 03 Security Architecture.
* CompTIA Security+ SY0-601 Study Guide: Chapter on Network Security and MAC Address Spoofing.

To increase the resilience of an application by splitting the traffic between two identical sites, a systems administrator should set up load balancing. Load balancing distributes network or application traffic across multiple servers or sites, ensuring no single server becomes overwhelmed and enhancing the availability and reliability of applications.
Load balancing: Distributes traffic across multiple servers to ensure high availability and reliability.
It helps in managing the load efficiently and can prevent server overloads.
Geographic disruption: Not a standard term related to resilience. This might imply the use of geographically distributed sites but isn't the precise solution described.
Failover: Refers to switching to a standby server or system when the primary one fails. It doesn't inherently split traffic but rather takes over when a failure occurs.
Parallel processing: Refers to the simultaneous processing of tasks, not specifically related to load balancing web traffic.

Port security is the best solution to prevent unauthorized devices, like a visitor's laptop, from connecting to the company's network. Port security can limit the number of devices that can connect to a network switch port and block unauthorized MAC addresses, effectively stopping unauthorized access attempts.
* Web application firewall (WAF) protects against web-based attacks, not unauthorized network access.
* Transport Layer Security (TLS) ensures encrypted communication but does not manage physical network access.
* Virtual Private Network (VPN) secures remote connections but does not control access through physical network ports.