The physical network consists of both an external physical LAN and the extension of the LAN within the host to a guest's network. Paravirtualized domains use the xnb backend driver in dom0 to communicate with a physical network interface.
The virtual network operates through the underlying physical network infrastructure.
You can create one physical network, also referred to as a switch, for each NIC on the system. If you have more than one physical NIC configured, you might want to configure the default-nic property of the xvm/xend SMF service, as described in the xend(1M).
To view the IP address assigned through DHCP, use the ifconfig command.
See the document New Network Options, Including Limiting Bandwidth and Setting a VLAN ID, for Virtual Network Interfaces Attached to a Guest to learn about conventions for network options used in the virt-install utility.