Difference Between IPv4 and IPv6

Difference between IPv4 and IPv6

In this comparison table you will have in depth knowledge of difference between IPv4 and IPv6.



Developed in 1974 by IETF Developed by IETF in 1998
Ipv4 address is 32 bit IPv6 address is 128 bit
Has issue with IP address depletion, due to Address shortage Has sufficient address to cater the needs of future as well
IPv4 header is 20 bytes IPv6 header is 40 bytes
IPv4 header has 13 fields and is more complicated IPv6 header has 8 fields and is less complicated to IPv4
IPv4 uses concepts of Classes, namely Class A through F IPv6 is Classless
Subnet Mask is used in IPv4 Prefix Length is used in Ipv6
No Built-in Security mechanism. IP sec is optional Has Built-in Security : Encryption and Authentication
Less suitable for Mobile networks Better Suited for Mobile networks
The IPv4 address is represented in dotted decimal The IPv6 address is represented in Hexadecimal and uses colon separate d notation
IPv4 is still widely used IPv6 is picking up but still behind IPv4
Addresses are of types : Private, Public and Multicast Address are of Global, Unicast and Anycast
For DNS the A record is used For DNS the AAAA record is used
Checksum available in IPv4 header No Checksum in IPv6 header
Uses ARP to map a IP address to a MAC address Uses Neighbor Discovery Protocol (NDP) in place of ARP.
Manual configuration is required or need to use DHCP Address can be configured automatically
Packet flow is not identified Uses the Flow Label to identify the Packet Flow
Uses Broadcast addresses Uses link local Scope all node multicast address
Number of addresses : 2^32 Number of addresses : 2^128
Example of an IPv4 : Example of IPv6 : FE80:0002:0000:0000:0102:A3EF:FE1F:8259
The sending host and the router do the fragmentation Here only hosts do the fragmentation and not the routers

IPv4 header



Type of Service




Fragment Offset

Time to Live ( TTL)


Header Checksum

Source IP address

Destination IP Address




IPv6 Header

Version Traffic Class

Flow Label

Payload Length

Next Header Hop Limit

Source IP Address

Destination IP Address

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