IPv4 is the address that you want to know as it becomes your device ID. Although IPv6 is existed and used everywhere IPv4 is still the most popular because IPv4 is easier to remember than the long IPv6 address.
IP version 4 is an address of your computer or smartphone in the network or internet. The format is like xxx.xxx.xxx.xxx if you ever read or heard IP address 220.127.116.11 that is the IPv4 address.
If you want to know what is your current IPv4 address is by typing IP address on Google and it will show you the public IP address.
IP public is the address that recognizes by the other devices on the Internet, while IP private addresses only recognize by your internal network. To show your current IPv4 private address, on the command prompt type ipconfig
Version 4 IP address (often referred to as IPv4 address) is a type of network addressing used in TCP / IP network protocols that use the version 4 IP protocol.
The total length is 32-bit, and theoretically, it can address up to 4 billion computer hosts or more precisely 4,294,967,296 hosts worldwide. The number of hosts obtained from 256 (obtained from 8 bits) is ranked 4 (because there are 4 octets) so that the maximum value of the version 4 IP address is 255.255.255.255 where the value is calculated from zero so Host values that can be accommodated are 256 × 256 × 256 = 256 = 4,294,967,296 hosts, if the hosts that exist worldwide exceed the quota then IP version 6 or IPv6 is made. An example of a version 4 IP address is 192.168.1.128.
What is IPv6 Address?
Its total length is 128-bit, and theoretically, it can address up to 2128=3,4 x 1038 host computers worldwide. Examples of IPv6 addresses are 21da: 00d3: 0000: 2f3b: 02aa: 00ff: fe28: 9c5a.
What are IPv1, IPv2, IPv3, and IPv5?
All of those IP versions above are experimental and never used publicly.
Version 4 IP addresses are generally expressed in dotted-decimal notations, which are divided into four 8-bit octets. In some reference books, the format is w.x.y.z. Because each octet is 8-bit in size, its value ranges from 0 to 255 (however, there are some exceptional values).
The IP address that is owned by a host can be divided by using the network subnet mask into two parts, namely:
Network Identifier / NetID or Network Address used specifically to identify the network address where the host is located. In many cases, a network identifier address is the same as a physical network segment with restrictions set and defined by IP routers. However, there are cases where several logical networks exist within the same physical network segment using a practice called multinetting.
All systems on the same physical network must have the same network identifier address. Network identifiers must also be unique in an internetwork. If all nodes in the same logical network are not configured using the same network identifier, then there is a problem called a routing error.
The network identifier address must not be 0 or 255. HostID or Host address (host address) that is used specifically to identify the host address (can be a workstation, server or other system based on TCP / IP technology) on the network. The host identifier value cannot be 0 or 255 and must be unique in the network identifier / network segment where it is located.
Types of addresses
IPv4 addresses are divided into several types, as follows:
an IPv4 address that is determined for a network interface that is connected to an IP Internetwork. Unicast addresses are used in point-to-point or one-to-one communication.
an IPv4 address that is designed to be processed by every IP node in the same network segment. A broadcast address is used in one-to-everyone communication.
is an IPv4 address that is designed to be processed by one or several nodes in the same or different network segments. Multicast addresses are used in one-to-many communication.
In RFC 791, the IP address version 4 is divided into several classes, seen from the first octet, as shown in the table. Actually what differentiates the IP class version 4 is the binary pattern contained in the first octet (mainly the initial bits / high-order bits), but for easier recall, it will be remembered more quickly by using decimal representations.
IP address classes
First Octet (Decimal)
First Octet ( Binary)
Unicast address for large scale networks
Unicast address for medium to large scale networks
Unicast address for small scale networks
Multicast address (not a unicast address)
Recommended: generally used as an experimental (experimental) address; (not a unicast address)
Class A addresses are given for large scale networks. The highest bit serial number in the class A IP address is always set to the value 0 (zero). The next seven bits – to complete the first octet – will create a network identifier. The remaining 24 bits (or the last three octets) represent the host identifier. This allows class A to have up to 126 networks, and 16,777,214 hosts per network. Addresses with the initial octet 127 are not permitted, because they are used for the Interprocess Communication (IPC) mechanism in the machine in question.
Class B addresses are reserved for medium to large scale networks. The first two bits in the first octet of the class B IP address are always set to a binary number 10. The next 14 bits (to complete the first two octets), will create a network identifier. The remaining 16 bits (the last two octets) represent the host identifier. Class B can have 16,384 networks, and 65,534 hosts for each network.
Class C IP addresses are used for small scale networks. The first three bits in the first octet class C address are always set to a binary value of 110. The next 21 bits (to complete the first three octets) will form a network identifier. The remaining 8 bits (as the last octet) will represent the host identifier. This allows the creation of a total of 2,097,152 networks, and 254 hosts for each network.
Class D IP addresses are provided only for multicast IP addresses, but they are different from the three classes above. The first four bits in class D IP are always set to binary number 1110. The remaining 28 bits are used as addresses that can be used to identify hosts. To more clearly recognize this address, look in the IPv4 Multicast Address section.
Class E IP addresses are provided as “experimental” or experimental addresses and are intended for future use. The first four bits are always set to the binary number 1111. The remaining 28 bits are used as addresses that can be used to identify the host.
Network Identifier part
Host Identifier part
Maximum Network Number
Maximum Host Number
Note: The use of IP address classes now is no longer relevant, considering that now IP addresses no longer use address classes. Internet authority developers have clearly seen that addresses divided into classes like the one above are not enough to meet the needs that exist today, when the use of the Internet is increasingly widespread. The new IPv6 address now does not use classes such as IPv4 address. Addresses that are created regardless of class are also called classless addresses.
Each network interface that uses the TCP / IP protocol must be identified using a unique logical address, called a unicast address. Unicast addresses are called logical addresses because they are addresses that are applied at the network layer in the DARPA Reference Model and do not have a direct relationship to the addresses used at the network interface layer in the DARPA Reference Model. For example, a unicast address can be assigned to a host with a network interface with Ethernet technology, which has a 48-bit MAC address.
This unicast address must be used by all TCP / IP hosts to connect to each other. Components of this address are divided into two types, namely the host address (host identifier) and network address (network identifier).
Unicast addresses use classes A, B, and C from the IP classes mentioned earlier, so the address space is from 1.x.y.z to 223.x.y.z. A unicast address is distinguished from other addresses by using a subnet mask scheme.
Types of unicast addresses
If there is an intranet that is not connected to the Internet, all IP addresses in the classroom unicast address can be used. If the connection is made directly (using routing techniques) or indirectly (using a proxy server), then there are two types of addresses that can be used on the Internet, namely public address (private address) and private address (private address).
public addresses are addresses that have been assigned by InterNIC and contain several network identifiers that have been guaranteed to be unique (that is, no two hosts use the same address) if the intranet is connected to the Internet.
When several public addresses have been established, several routes can be programmed into a router so that data traffic to the public address can reach its location. On the Internet, traffic to a destination public address can be achieved, as long as it is still connected to the Internet.
Personal intranets that do not have the will to connect to the Internet can choose whatever address they want, even if they use a public address set by InterNIC. If an organization further decides to connect its intranet to the Internet, the address scheme it uses may contain addresses that may have been assigned by InterNIC or other organizations. These addresses can become conflicts between one another, so they are also called illegal addresses, which cannot be contacted by other hosts.
Each IP node requires an IP address that is globally unique to IP Internetwork. In the case of the Internet, each node on a network connected to the Internet will need a global address that is unique to the Internet. Because of the very rapid development of the Internet, organizations that connect their intranets to the Internet need a public address for each node in their intranet. Of course, this will require a public address that is globally unique.
When analyzing the addressing needs needed by an organization, Internet designers have the idea that for most organizations, most hosts on the organization’s intranet do not have to be connected directly to the Internet. Hosts that require a set of Internet services, such as access to the web or e-mail, usually access these Internet services through a gateway that runs above the application layer such as a proxy server or e-mail server. As a result, most organizations only need a small number of public addresses that will be used by these nodes (only for proxy, router, firewall, or network address translators) that are connected directly to the Internet.
For hosts within an organization that do not need direct access to the Internet, IP addresses that are not duplicates of predetermined public addresses are absolutely necessary. To overcome this problem of addressing, Internet designers have reserved a portion of the IP address space and refer to this section as the private address space. An IP address that is in a private address space will not be used as a public address. IP addresses in the private address space are also known as private addresses. Because between the public address room and the private address room do not overlap, the private address will not duplicate the public address, and vice versa. A network that uses a private IP address is also called a private network.
The private address space specified in RFC 1918 is defined in the following three address blocks:
10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 Meanwhile, there is also an address space that is used for private IP addresses in several operating systems:
169,254.0.0/16 10.0.0.0/8 The private network 10.0.0.0/8 is a class A network identifier that allows valid IP addresses from 10.0.0.1 to 10,255,255.254. The private network 10.0.0.0/8 has 24 host bits which can be used for subnetting schemes within a private organization.
172.16.0.0/12 The private network 172.16.0.0/12 can be interpreted as a block of 16 class B network identifiers or as an address space that has 20 bits that can be set as host identifiers, which can be used by using a subnetting scheme in a private organization. The private network address 172.16.0.0/12 allows valid IP addresses from 172.16.0.1 to 172.31.255.254.
192.168.0.0/16 The private network 192.168.0.0/16 can be interpreted as a block of 256 class C network identifiers or as an address space that has 16 bits that can be set as host identifiers which can be used using any subnetting scheme in a private organization. The private network address 192.168.0.0/16 can support valid IP addresses from 192.168.0.1 to 192.168.255.254.
169,254.0.0/16 This network address can be used as a private address because IANA allocates not to use it. The possible IP addresses in this address space are 169.254.0.1 through 169.254.255.254, with the subnet mask address 255.255.0.0. This address is used as an automatic private IP address (in Windows, called Automatic Private Internet Protocol Addressing (APIPA)).
The result of the use of these private addresses by many organizations is to avoid running out of public addresses, given the rapid growth of the Internet.