If network hosts are not configured with a VLAN ID, how should the ports on the switch be configured?

When network hosts are not configured with a VLAN ID, the best approach is to set up the switch ports in a way that allows proper communication without requiring the hosts themselves to be aware of VLAN tagging. Configuring a port as an untagged connection for a specific VLAN means that any device connected to that port will communicate on that VLAN without needing to understand or manage the VLAN ID.

This method is particularly effective for end devices, such as computers or printers that do not support VLAN tagging. By making the port untagged for VLAN 20, any device connected will automatically be part of that VLAN, facilitating their communication on the network without additional configuration on the hosts.

Other configurations, such as tagging ports or leaving them without a specified VLAN, may not be suitable for devices that are unaware of VLANs. Tagged connections require the device to understand VLAN IDs, and non-VLAN configurations could lead to a lack of network connectivity.