Oracle VM VirtualBox - Oracle Solaris 10 System Virtualization Essentials - page 142

The guest can be accessed by using ssh -p 2222 user@host .
Bridged is a more advanced network mode. When working in this mode,
VirtualBox installs a software network that allows the guest to share a specific
host interface. A randomly generated MAC address is assigned to the guest
adapter and its full network stack is visible to external systems. All of the net-
work operations are available to the guest, including ping and jumbo frames. The
bridged mode is the recommended setting for guests running server applications
and desktops requiring a VPN connection into another network.
Internal mode is used to communicate between virtual machines on the same
host. It is similar to bridged mode except that all communications stay internal
to the host platform. Traffic over the internal mode software network is also in-
visible to the host. Internal mode is the fastest and most secure method of com-
munication between guests. The most common use for this mode is to establish a
private secure channel for guests to share that cannot be observed by any external
system or other applications on the host system. Examples include an internal
NFS server or a content provider for an externally facing web service.
Host only mode is similar to internal mode except that the host is able to
communicate with the guests. All communications are internal to the host, but
applications and users on the host can observe and use network services on the
guests.
Basic network settings for the first four adapters, as shown in Figure 5.6, can
be specified on the Network settings screen in the VirtualBox graphical interface.
Figure 5.6 Oracle VM VirtualBox Guest Network Configuration Settings