Jennifer most likely seeing ARP Poisoning .
Explanation:
ARP or Address Resolution Protocol poisoning refers to when an attacker uses his devices to send falsified ARP messages over a LAN in order to link the attacker’s MAC Address with the IP addresses of one or more legitimate computers on the server.
Through this, the attacker is able to receive any message the legitimate computer received as well, allowing the attacker to block, modify or even intercept the communications of the legitimate computer on the server. The symptoms shown in the case here, showing intermittent connection losses even though no large downloads are taking place.