Subinterfaces: Subinterfaces are virtual interfaces created on a physical router interface, each associated with a specific VLAN or subnet. By configuring subinterfaces, the router can effectively handle traffic from multiple subnets, allowing traffic separation while still enabling communication between the finance and marketing teams. Each subinterface is associated with a different VLAN or subnet and can have its own IP address, allowing traffic to be routed between subnets while keeping them logically separated.