A MAC Address or Media Access Control Address is a unique number given to every Network Interface Card (NIC) which forms the interface between the network and the hardware. It is usually a 48bit number which is hard coded into the hardware during manufacturing. MAC address is written in hexadecimal format and is divided into 6 octets. Typically a MAC address looks like 00:0A:FF:C3:5B:88 or 00-0A-FF-C3-5B-88. It is a globally unique number, that is no two devices will have the same MAC address.
To ensure uniqueness, a central regulatory body controls the numbering system. Every network equipment manufacturers are assigned a unique 24bit number that forms the first three octets of the MAC. This is called OUI or organizationally Unique Identifier. Large manufacturers like CISCO, Belkin etc may have multiple OUIs. The rest 24bits are assigned by the manufacturer.
When a device is connected to the network, the MAC address will be associated with a unique IP address. IP address unlike MAC is assigned by the software. IP may change the next time you connect the same device to the network but MAC will never change. The ARP (Address Resolution Protocol) Table stores a list of all the IP and its corresponding MAC during a particular session.
A single device such as switches, routers etc can have multiple Network Interface Cards each having a unique MAC. To find the MAC address of your PC use commands like ipconfig in windows or ifconfig in Linux. A list of all network adapters with their MAC and other details will be listed.
To ensure uniqueness, a central regulatory body controls the numbering system. Every network equipment manufacturers are assigned a unique 24bit number that forms the first three octets of the MAC. This is called OUI or organizationally Unique Identifier. Large manufacturers like CISCO, Belkin etc may have multiple OUIs. The rest 24bits are assigned by the manufacturer.
When a device is connected to the network, the MAC address will be associated with a unique IP address. IP address unlike MAC is assigned by the software. IP may change the next time you connect the same device to the network but MAC will never change. The ARP (Address Resolution Protocol) Table stores a list of all the IP and its corresponding MAC during a particular session.
A single device such as switches, routers etc can have multiple Network Interface Cards each having a unique MAC. To find the MAC address of your PC use commands like ipconfig in windows or ifconfig in Linux. A list of all network adapters with their MAC and other details will be listed.
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