What is IPv6 Address?

First of all, a general question will come to our mind that; what is IP?

IP means Internet Protocol so easily we can say, it is an address or an identifier or ID for a device in the network, when people communicate to each other they call and communicate generally by the name so in daily communication the name between human is an identifier for communication, so in computer networking each device must have a unique name in a network, so that unique name is IP Address, for example: PC Left will send a file to PC right so left PC must know the IP Address of right PC to send the file to that PC. We will assign an address for left and also an address for right pc

PC1 Address; 2001:10BA:11BA:12BA::1
PC2 Address; 2001:10BA:11BA:12BA::2

Take care! When you want to assign addresses to the devices, you must remember that all numbers cannot be valid address for the device, there is some rules (Protocol) when you assign an address to a device.

Before mentioning the rules: I want to say that there is two versions of IP:

1. IPv4

2. IPv6

In this topic I will give you full information about IPv6.


We all know that IPv4 have a length of 32 bit with 4 portion/ octet, ipv6 have a length of 128 bit with 8 portions, each portion is 16 bit, each portion in maximum, can hold 4 value (Hexa-Decimal) Numbers.

zoom of one portion

Numbers can be:

  • Binary (base 2)
    • 0, 1
  • Octal (base 8)
    • 0, 1, 2, 3, 4, 5, 6, 7
  • Decimal (base 10)
  • Hexa-Decimal (base 16)  
    • 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F (A=10, B=11, C=12, D=13, E=14, F=15)

Now as we know ipv6 length is 128bit with 8 portion each portion is 16 bit, hexa-decimal numbers. It has a very large address space 2128 and we delimit each portion with “:” it only support /value or CIDR Notation when defining Network and Host Parts.

For example:


At upper example we cannot differentiate Network and Host section, so we only use CIDR Notation (/value) to determine network and host section.

So to correct the example.


Now we know that 4 portion (64bit) belongs to network and 4 portion (64bit) belongs to host.

In next topic we will talk on: IPv6 and IPv4 similarities, IPv6 and IPv4 differences, Making IPv6 shorter, IPv6 Address Types, Assigning IPv6 Addresses, IPv6 features, EUI-64…

5 thoughts on “What is IPv6 Address?”

Leave a Comment