In this mode, VirtualBox uses a device driver called net filter on the host system that filters data from the host's physical network adapter. Net filter helps VirtualBox to translate data from a physical network and inject data into it. Actually, it creates a software network interface.

By using this software adapter, the host sends data to the guest and receives data from it. This means it acts as a bridge between the host and the guest VM. This interface can be used for routing between the guest VM and the network.

A bridge network can be configured from the VirtualBox GUI. To do this, open the Settings dialog of a virtual machine, click on the Network tab, and select Bridged Adapter. In this mode, just like the host, each guest VM can access the physical network. It can access any external services, such as NTP, DNS, and so on.

This network is shown in the following figure:

The disadvantage of this mode is that, if your host has multiple physical NICs, then you have to reconfigure the bridge when you move across networks.