What are the first 24 bits in a MAC address called?

Historically, MAC addresses were 48 bits long. They have two halves: the first 24 bits form the Organizationally Unique Identifier (OUI) and the last 24 bits form a serial number (formally called an extension identifier).

What is the first half of a MAC address?

24 BITS
The first half (24 BITS) of a MAC address contains the ID number of the adapter manufacturer. These IDs are regulated by an Internet standards body (see sidebar). The second half (24 MORE BITS) of a MAC address represents the serial number assigned to the adapter by the manufacturer.

How many bits are in a MAC address?

Every MAC address includes 48 bits, or 6 bytes, and is arranged in the following pattern: 00:81:41:fe:ad:7e. The first 24 bits are the manufacturer code assigned by the Institute of Electrical and Electronics Engineers (IEEE), and the following 24 bits are the device number defined by the manufacturer.

How are MAC addresses used in MAC spoofing?

This masking is what’s referred to as MAC spoofing. MAC addresses: distinct hardware addresses identify network interface controllers (NIC) such as LAN cards or WLAN adapters, and are used to identify devices in local networks. Every MAC address includes 48 bits, or 6 bytes, and is arranged in the following pattern: 00:81:41:fe:ad:7e.

What is the second bit of a multicast address?

Multicast addresses are identified by I/G = 1 and are addressed to several receivers. Bit 2 (registry): The second bit of the MAC address indicates whether it is an address with global validity (universal) or whether the address has been assigned locally (local). The bit is called U/L.

How is the MAC address of a computer written?

MAC address syntax MAC addresses in LAN or WLAN networks consist of 6 bytes (48 bits) and are written in hexadecimal notation. The use of separators such as hyphens or colons between two bytes increases readability. The following example shows the MAC address of a desktop computer in binary and hexadecimal format: