Source: https://www.researchgate.net/profile/Johanes_Andry/publication/324311605_Design_and_Simulation_VLAN_Using_Cisco_Packet_Tracer_A_Case_Study/links/5b8887ab299bf1d5a733316d/Design-and-Simulation-VLAN-Using-Cisco-Packet-Tracer-A-Case-Study.pdf