A MAC (Medium Access Control)
addresses refers to hardware addresses or physical addresses, which is a unique
value assigned to network adapters on LAN at the time of manufacture. Hence,
these addresses are sometimes known as 'Burned In Addresses' (BIA). Since these
addresses are created in the Ethernet specification they are also known as
'Ethernet addresses'. If a MAC address is assigned by the manufacturer it helps
in encoding the manufacturers registered identification number. MAC addresses
are also used to identify each node distinctly in a network. They are available
on the data link layer of the OSI mode. The data link layer comprises two
sublayers i.e., MAC and LLC (Logical Link Control). The MAC layer communicates
directly with the network medium. As a result a distinct MAC sublayer exists
for every distinct type of network medium.
A remote access to the internet
from a local computer results in the creation of a table on LAN that relates IP
address and MAC address of local computer. The MAC sub layer has the capability
of controlling the way with which a network node accesses and transmits the
data. A MAC address is used by the following technologies like Ethernet,
802.11, Bluetooth, Token ring, FDDI, SCSI, ATM and Fiber channel.
MAC addresses are 48 bits long
and are represented as 12 digit hexadecimal number separated by colons (:) or
hyphens (-). The format of MAC address is follows,
AA:AA:AA:BB:BB:BB (or)
AA-AA-AA-BB-BB-BB
The first half i.e.,
AA:AA:AA/AA-AA-AX specifies the ID of the adapter's manufacturer and the second
half i.e., BB:BB:BB/BB-BB-BB specifies the serial number associated with the
adapter. This serial number is assigned by the manufacturer to the adapter.
To formulate a MAC address,
three numbering systems such as MAC-48, EUI-48 and EUI-64 are commonly used.
These numbering systems are managed by the IEEE (Institute of Electrical and
Electronics Engineer) standard. Although, MAC address refers to a permanent and
unique identification number, its value can be changed. This action of changing
the MAC address is usually known as MAC spoofing. There is a difference between
MAC spoofing and IP spoofing. In IP address spoofing, when a sender spoofs its
address in a request the response is received by an unintended entity, whereas,
in MAC address spoofing, the response is received by the spoofing party. Using
MAC address, the location of a host cannot be determined.
The communication between
subnet MAC address and IP address in TCP/IP suite can be made possible using IPv4
or IPv6 internet protocol versions. IPv4 uses Neighbour Discovery Protocol
(NDP), whereas IPv6 uses Address Resolution Protocol (ARP) for enabling such
communication. In broadcast networks like Ethernet, MAC address is used to
identify each node in the network and to assign frames for some particular
hosts. Thus, most of the link layer protocols, upon which upper layer protocols
rely, use this address so as to produce complex functioning networks.
To check MAC adress:
- Open Start menu and open cmd
- Then type ipconfig/all and press enter
- There you can find your MAC address.
Very beautifully described about the addresses. Joomla development
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