...
Computers communicate with each other using predefined protocols. A protocol is the set of rules that define the way how two entities can communicate across the network. It would speicify specify patterns of communcation communication and data structures. Each layer of the OSI 7 layer models is goverend governed by 1 or more protocols, such as TCP, IP, UDP, ARP, DHCP, FTP, and so on.
In order for computers to be able to identify each other on a network, they need an identifier. There are several types of identifiers used in the network.
Hostname
A unique device name (names can clash) on the network
Open a command prompt and type hostname
IP Address (Logical Address)
The IP Address is the network address of the system across the network. Notice we say the system here and not the device. More on this later. It is assigned to the system when it is bootstrapped, and it can be changed at any time whilst the system is actively running.
To identify each device in the world-wide-web, the Internet Assigned Numbers Authority (IANA) assigns an IPV4 (Version 4) address as a unique identifier to each device on the Internet. There are more devices in the world than there are IP addresses, so addresses are distributed based on organizational requirements.
The length of the address is 32-bits for IPv4, giving us an available 232 IP addresses. Or 128-bits for IPv6 giving us an available 2128 IP addresses.
MAC Address (Media Access Control) - Physical Address
The MAC Address is the unique identifier of each node and is associated with its NIC (Network Interface Card). A MAC address is assigned to the NIC at the time of manufacturing. It can not be changed.
The length of the MAC address is : 12-nibbles == 6 bytes == 48 bits
| Info |
|---|
A nibble is 4-bits |