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1.9 IDENTIFICATION OF COMPUTERS AND USERS OVER A NETWORK
                 After a network has been established, the nodes can communicate with one another. However, the nodes must be
                 uniquely recognised to communicate properly. If node X sends information to node Y on a network, both nodes X and
                 Y must be uniquely identified on the network. Let’s have a look at how this is accomplished.

                 MAC Address

                 The manufacturer assigns a universally unique address to each NIC. The MAC (Media Access Control) address of the
                 card is this address. It means that the MAC address of a machine’s NIC can be used to uniquely identify it. A NIC’s MAC
                 address is static and does not change.
                 MAC addresses are hexadecimal (48-bit) integers with 12 digits. MAC addresses are commonly written in one of two
                 formats, according to convention:

                                            MM:MM:MM:SS:SS:SS               MM-MM-MM-SS-SS-SS

                 A MAC address’s first half (MM:MM: MM) contains the adapter manufacturer’s ID number. The serial number assigned
                 to the adapter (NIC) by its manufacturer is represented by the second half (SS:SS: SS) of a MAC address.
                 For instance, consider the MAC address 00:A0:C9: 14:C8:35. The manufacturer is Intel Corporation, as indicated by the
                 prefix 00:A0:C9. The last three numbers 14:C9:34 are assigned to NIC by the manufacturer (Intel in this case).

                 IP Address

                 Every machine on a network has its own unique identifier, known as an IP Address. An IP address consists of four bytes
                 (32 bits), each of which can be any integer between 0 and 255. The following is an example of a typical IP address:
                 192.077.134.72
                 IP addresses are usually written in decimal format as a “dotted decimal number” like the one above to make them
                 easier to remember. On a network, a machine’s IP address, not its NIC’s MAC address, is used to identify it. The user
                 can update a node’s IP address settings.

                 You might be wondering what the difference is between an IP address and a MAC address. Let’s have a look:

                                     Mac Address                                          IP Address
                  It is a hexadecimal address of six bytes.          This address can be either eight or six bytes long.

                  A device's MAC address is provided by the manufacturer of the  The  IP  address  of  a  device  is  provided  by  an  ISO  (Internet
                  NIC card.                                          Service Provider).
                  A  MAC  address  is  mostly  used  to  verify  a  device's/physical  The logical address of a computer is defined by the IP address.
                  computer's address.
                  When a machine is moved from one network to another, its  When a machine is moved from one network to another, its IP
                  MAC address remains the same.                      address gets changed.
                  Wing R to Wing P                                   450 m
                            Notes



                           There are two versions of IP addresses that are currently existing on the global Internet—IP version 4 (IPv4) and
                           IP version 6 (IPv6). IPv4 is 32 bits long whereas IPv6 is 128 bits long. Both versions can coexist on a network.



                 Domain Name

                 As a result, we may communicate with a computer over the internet by utilising its IP address. However, remembering
                 the IP addresses of all the machines with whom one might need to communicate is almost difficult. As a result, a system
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