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As the number of Internet of Things (IoT) continues to expand exponentially, with more than 30 billion devices already connected to the internet, there is a fear that we would run out of IPs at one point. And, you would be surprised to know that we have completely run out of IPv4 addresses!

An IP (Internet Protocol) address is a label assigned to each device that is connected to a network. An IP address acts as an identifier for devices. In this blog, we will explain the difference between IPv4 and IPv6. Before getting into details, here are the key differences between IPv4 and IPv6.


  • IPv6 is a 128-bit address, whereas IPv4 is a 32-bit address.
  • IPv6 uses an alphanumeric addressing method, whereas IPv4 uses numeric addressing.
  • IPv6 binary bits are separated by (:) colon, whereas in IPv4 they are separated by a (.) dot.
  • IPv6 offers 8 header fields, whereas IPv6 offers 12 headers.
  • IPv6 doesn’t support broadcast, whereas IPv4 supports broadcast.
  • IPv6 doesn’t support VLSM (Variable Length Subnet Mask), whereas IPv4 supports VLSM.
  • IPv6 uses NDP (Neighbor Discovery Protocol) to map MAC addresses, whereas IPv4 uses ARP (Address Resolution Protocol).

What is IPv4?

IPv4 is a version of an IP address that is used to identify devices on a specific network using the address system. It has been used since the early 1983’s. IPv4 uses a 32-bit address scheme to store 2*32 addresses – that is, around 4 billion addresses. IPv4 is the primary Internet Protocol that is responsible for 94% of internet traffic.

What is IPv6?

IPv6 is the newer version of Internet Protocol, as compared to IPv4. It was launched in 1994 to cater to the need for more IP addresses and resolve issues related to IPv4. In contrast to IPv4, IPv6 uses a 128-bit address scheme that has over 340 undecillion address space. IPv6 is also called Internet Protocol next generation (IPng). IP fragmentation in IPv6 works a bit differently than IPv4. In IPv6, data can only be fragmented on the source host.

Features of IPv4

Here are some notable features of IPv4:

  • Connectionless protocol
  • It requires less memory and easily remembers addresses
  • It is supported by millions of devices

Features of IPv6

Here are some features of IPv6:

  • Stateful configuration
  • Supports quality of service (QoS)
  • The best protocol for neighboring node interaction
  • Hierarchical addressing

Difference Between IPv4 and IPv6 Addresses

Both IPv4 and IPv6 are used to identify devices connected to the network. In general, both are the same, but they work differently. Here are some main differences between IPv4 and IPv6.

IPv4 IPv6
Size of IP address 32-bit IP addresses 128-bit IP addresses.
Addressing Method Numeric address, with binary bits separated by a dot (.) Alphanumeric address with binary bits separated by a colon (:)
Number of header fields 12 8
Length of header fields 20 40
Types of Addresses Unicast, broadcast, and multicast Unicast, multicast, and anycast.
Number of classes 5 classes of IP address from Class A to E Allows storing an unlimited number of IP address
VLSM support Supports VLSM Does not support VLSM
Security IPv4 does not have a dedicated security protocol and is dependent on applications. IPSec is built into IPv6 and is usable with proper infrastructure.
Packet size 576 bytes required, fragmentation is optional 1208 bytes required without fragmentation
Packet fragmentation From the route to sending host Sending host only
DNS record Address (A) record, also maps a hostname Allows (AAAA) record, also maps a hostname
Address configuration Manual or DHCP Stateless address configuration with Control Message Protocol version 6 (ICMPv6) or DHCPv6.
Mapping Uses ARP (Address Resolution Protocol) to map MAC addresses Uses Neighbor Discovery Protocol (NDB) to map MAC addresses
IPSec (Internet Security Protocol) IPSec is optional IPSec is mandatory
Compatibility with mobile devices IPv4 is not suitable for mobile networks because it uses dot (.) notation. IPv6 is better suited for mobile devices because it uses a colon (:) notation.
Example 12.345.678.910 1234:0b8cd:0000:gg000:84g9
Network configuration Needs to be configured either manually, or with DHCP. Has several overlays to handle internet growth, so requires more maintenance. Supports autoconfiguration capability.
Best feature Use of NAT (Network Address Translation) devices that allows one NAT address to mask thousands of non-routable addresses. IPv6 allows direct addressing because of the vast IP address space available.

How to disable IPv6 in Windows, Linux, and Mac?

Since very few networking devices support IPv6, it may leak your information online, including MAC address, online activity, and more. You can disable IPv6 on your device, and use a VPN to secure your connection. IP Multicast Routing efficiently delivers large amounts of data from one source to multiple destinations simultaneously. Follow these steps below to disable IPv6 on your Windows, Mac, and Linux:

For Windows

  1. Go to Start > search for Control Panel > Click
  2. Go to Network and Sharing
  3. Head to Change Adaptor Settings
  4. Right-click on your Internet connection > Properties
  5. Scroll down and uncheck ‘Internet Protocol Version 6 (TCP/IPv6)
  6. Click OK and restart your device.

For macOS

  1. Go to System Preferences
  2. Click Network
  3. Select your internet connection > Advanced > <br/>
  4. Go to TCP/IP tab > Configure IPv6 > Off
  5. Click OK

For Linux

  1. Go to Setting > Network
  2. Click Settings tab for your network
  3. Switch to IPv6 > IPv6 Method > Disable
  4. Click Apply, and you are good to go.

IPv4 and IPv6: How to protect your IP address?

Your IP address shows your location, so it comes with security and privacy issues. For example, your ISP and hackers can snoop and spy on your online activities. Websites also use your IP address to restrict access to content. However, with a VPN, you can mask your real IP and protect yourself.

We recommend ExpressVPN for spoofing your geo-location. It has over 3000+ servers that you can choose from to get a different IP address.

Read our dedicated ExpressVPN review for more details.

FAQs: IPv4 and IPv6

IPv4 and IPv6 are not compatible with each other, which means that you cannot use both at the same time. However, ISPs have come up with a method called Dual Stack that allows networking devices to be configured with both IPv4 and IPv6 connectivity. This way, both IPv4 and IPv6 traffic is processed simultaneously.

As discussed above, we are switching to IPv6 because we have run out of IPv4 addresses. With the exhaustion of the IPv4 pool and a growing need for IP addresses, we have no choice but to switch.

IPv4 uses Network Address Translation (NAT) that allows multiple devices to share the same IP address. But, with IPv6, you have so many IP addresses at your disposal that you don’t need NAT.

Follow these steps to enable IPv4 and IPv6 on your Windows PC:

  • Go to Settings > Network and Sharing Center
  • Go to Change Adaptor settings
  • Right-click on your device connection (Ethernet in most cases) click Properties.
  • Under ‘This connection uses the following items: check Internet Protocol Version 4 and Internet Protocol Version 6.’
  • Click OK and restart your device.


IPv4 and IPv6 are internet protocols that are associated with the devices that are connected to the internet. Think of these as an identifier for each device on the internet. Your IP address also stores your geo-location and other information like the device you are using and more.

Therefore, it poses a variety of online security and privacy issues. Fortunately, with a VPN you can hide your IP address and anonymize your online activities to help keep your data secure all the time.