With the increasing adoption of cloud computing and the growing reliance on networked infrastructure, improving cloud network security has become an increasingly vital concern. One critical aspect of network security is monitoring, which involves keeping track of the connected devices to the network and detecting potential security threats such as IP and MAC address duplications. To address these challenges, this thesis focuses on providing a customized monitoring system based on the data of ARP tables of the routers in a network. The system receives the exported data of the routers in regular intervals and analyzes the IP and MAC of each line of the files.