A hardware address identifies an interface within a link-layer context, while an IP address supports communication at the network layer. The two serve different purposes and can change under different rules.
How the pieces connect
An operating system can use address-resolution mechanisms to connect a network-layer destination with the next relevant local-link participant. Routers then move traffic between networks. Wireless privacy features and virtual interfaces can also affect the hardware address presented in a particular context. Neither address should be treated as a universal permanent identity for a person.
An everyday example
A laptop may receive a different IP address when it joins another network while using the same physical radio. A privacy setting can also present a different link-layer address for a wireless network. These changes do not necessarily indicate replacement hardware; they can be normal consequences of network configuration and privacy behavior.
Reading the information in context
Addresses are not passwords, but they can still reveal information about a network or device and should not be shared indiscriminately. A hardware identifier used to match a software package is yet another concept, separate from both address types. Keep the context attached to any recorded value, and avoid posting complete network-property exports when a single non-sensitive field would answer the question.
Network & Wi-Fi
Note these before you change anything
Useful facts to have to hand while reading about hardware addresses and ip addresses.
- Adapter name and driver version
- Whether other devices on the same network work
- IP configuration shown in the system's network details
- Power-saving settings on the adapter
Network & Wi-Fi: Sending data (simplified; replies return the same way)
- Applicationopens a connection
- Network stackTCP/IP and name lookup
- Adapter driverWi-Fi or Ethernet
- Network adapterradio or port
- Routerand the wider network
