physical device address

基本解释

The never-changing MAC provides a specific, reliable address for a physical device.
而永不變化的MAC地址給物理設備提供了一個獨特可靠的地址。
Each guest operating system is mapped through the /dev/kvm device, having its own virtual address space that is mapped into the host kernel's physical address space.
每個來賓操作系統都是通過 /dev/kvm 設備映射的，它們擁有自己的虛擬地址空間，該空間映射到主機內核的物理地址空間。
A MAC address is a unique character string, and since it identifies a specific physical device -- one individual NIC -- the MAC address, by convention, never changes for the life of the NIC.
一個MAC地址是一個獨一無二的字符串。由於它標識一個獨特的物理設備——一個唯一的網卡——MAC地址，按照約定，在網卡中將永不會改變。

Security solutions based on physical infrastructure, and policy expressed in terms of a particular device, the corporate PC, an IP address, network port, or application protocol are becoming useless in a mobile, borderless world.
FORBES: Going Mobile: Security in the Age of Ubiquity