What is the physical address of the NIC

The MAC address is the address used by the Ethernet protocol, which works in the local area network, and is 48 bits long, which is generally represented by a hexadecimal number between 6 bits 00 and 0ffh separated by " ", such as "52 54 ab 22 40 87". The first digits are the manufacturer**, and each Ethernet NIC manufacturer must apply for a set of dedicated MAC addresses, and the last digits are the product serial numbers, and the MAC addresses are programmed in the EEPROM on the NIC card during the production of the NIC. Since the NIC sends and receives packets based on the MAC address, in principle, the MAC address of any two NICs should not be the same regardless of which manufacturer manufactures them.

However, due to various reasons, individual products will also have the same number, but generally sell in different regions.

The book says that the IEEE specifies the first three bytes of the NIC address for each hardware manufacturer, and the last three bytes are encoded by the manufacturer itself. That should be six digits for the network card address?

6 bytes is appropriate, or 6 digits in hexadecimal numbers).

But isn't the NIC address 00-0b-6a-e4-71-fc like that? How can there be only six here?

6-digit hexadecimal number, or 6 hexadecimal numbers).

Question added: How is 00-0b-6a three bytes, such as 6a, isn't it 00000110 00001010, it's sixteen here.

6a 0110 1010 This is a byte 8-bit binary number )

00-0b-6a, these three bytes are the vendor.

The physical address of the NIC is the actual address corresponding to the storage unit in the memory, also known as the physical address, which corresponds to the logical address.

A MAC (MediaAccessControl) address is an identifier that identifies a LAN (Local Area Network) node. The physical address of a network card is usually the EPROM (a flash memory chip, usually written by a program) burned into the network card by the network card manufacturer, which stores the addresses of the computer that really identifies the computer that sent the data and the host that received the data when transmitting data.

Main applications: That is to say, in the physical transmission process at the bottom of the network, the host is identified by the physical address, which is generally unique in the world. For example, the physical address size of a well-known Ethernet card is 48 bits (bits), the first 24 bits are the manufacturer number, and the last 24 bits are the NIC number, such as:

44-45-53-54-00-00, machine-readable to the host interface. The Ethernet Address Management Authority (IEEE) divides Ethernet addresses, that is, different combinations of 48 bits, into several independent contiguous address groups, and manufacturers who produce Ethernet network cards purchase one of them, and give unique addresses to Ethernet cards one by one during specific production.

1.The NIC address is the MAC (Media Access Control or Medium Access Control) address, which is used to define the location of network devices.

2.In the OSI model, the third layer network layer is responsible for IP addresses, and the second layer is responsible for MAC addresses. So a host will have a MAC address, and each network location will have an IP address that is unique to it.

The address is determined by the network card, which is fixed and unique. Figuratively speaking, the MAC address is like the ID number on the ID card, which is globally unique.

It's the physical address The actual address is the mac You right-click on the network neighbor dot properties Double-click the local connection Tag dot support and then click on the details The first real address in it is your NIC address.