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Does Ethernet use MAC addresses?
The MAC (Media Access Control) address is a devices hardware address. Each device on a local area network must have a unique MAC address assigned. The MAC address is often referred to as the Ethernet Address on an Ethernet network. They are in fact the same thing.
Does every device have a MAC address?
All devices on the same network subnet have different MAC addresses. MAC addresses are very useful in diagnosing network issues, such as problems with IP addresses. MAC addresses are useful for network diagnosis because they never change, as opposed to a dynamic IP address, which can change from time to time.
How are Ethernet MAC addresses assigned?
MAC addresses are primarily assigned by device manufacturers, and are therefore often referred to as the burned-in address, or as an Ethernet hardware address, hardware address, or physical address. Each address can be stored in hardware, such as the card’s read-only memory, or by a firmware mechanism.
What does the MAC address FF FF FF FF FF FF indicate?
The MAC address used for broadcast (broadcast MAC address) is ff:ff:ff:ff:ff:ff. Broadcast MAC address is a MAC address consisting of all binary 1s. Broadcast is “one to all” type of communication. In other words; “send once receive all”.
Why are Ethernet MACs called ” MAC ” addresses?
These are relevant in the MAC layer, which is of course why they are called “MAC” addresses in the first place. Every ethernet MAC is supposed to have a globally unique 48 bit address. I suppose it would be possible for a manufacturer to create MACs with built-in addresses and then serialize them in production.
Do you need an Ethernet controller for PHY?
The DP83TC811R-Q1 is a PHY implementation, and it connects to a MAC implementation driven by an Ethernet controller. To support this chip on an ESP32 would require that you select a MAC chip and connect that to the PHY…..but beyond that you need an Ethernet controller to build the protocol packets to be serialized.
Are there any Phys that do not have a MAC address?
Many PHYs do not have MAC addresses, in particular the cheapest ones as you need to pay for a block of MAC addresses and they leave that up to consumer. Example: the popular (at least among hobbyists) ENC28J60 does not have a pre-programmed MAC.
How does a MAC chip work with a PHY?
The MAC chip or layer receives bits from the PHY, detects packet boundaries, assembles bits into packets, and validates them. It also takes packets of data that are loaded into it and converts them to streams of bits which are fed to the PHY. Typically, a MAC will include some logic to delay transmissions until the line is clear,…