What Is CGNAT and Will It Impact Your Broadband Connection?

Internet real estate has become increasingly crowded in recent times, due to skyrocketing demand for IP (Internet Protocol) addresses. Fortunately, additional lodging opportunities are opening up and are set to continue being deployed in the coming years. However, in the meantime, many broadband providers have sought a stopgap in the form of CGNAT (Carrier-grade Network Address Translation) technology.

CGNAT effectively allows providers to stretch their current supply of IP addresses amid the ongoing rollout of a more comprehensive communications protocol. Many users won’t notice any difference in how they access the internet. However, depending on the specific services being used, some users could potentially experience connectivity issues.

Below we explore:

• What is an IP address and why are they in short supply?
• IP address shortage: What role does CGNAT play?
• How CGNAT could impact your online activities
• How to tell if you are on a CGNAT connection
• How to solve potential CGNAT-related issues

What is an IP address and why are they in short supply?

The internet has for some time been dealing with a shortage of IP addresses. Essentially, the internet architecture in its original form is unable to accommodate the ongoing rapid growth in its use. It simply does not having the capacity to cater for increased traffic.

This is by no means a new problem, and work has long been underway to implement both short and long-term solutions. This includes the creation of a new communications protocol with a far greater quantity of IP addresses.

The following are some key tech terms that will help to put this into context:

• IP (Internet Protocol) address – is a series of numbers assigned to internet-connected devices, identifying the device and enabling its connection and the transfer of data. Externally, your provider assigns a public IP address to your router. Internally, every device on a network has its own unique private IP address (assigned by the router).

• IPv4 (Internet Protocol version 4) – is the fourth version of the Internet Protocol, via which connecting devices are assigned addresses. Its 32-bit address format accommodates over 4.2 billion addresses. As advised above, address depletion has been an issue for some time.

• IPv6 (Internet Protocol version 6) – the sixth version of the Internet Protocol has emerged as the successor to IPv4. IPv6’s 128-bit format accommodates over 340 trillion trillion trillion addresses. It continues to be deployed, existing alongside IPv4.

According to Google, as of September this year, the IPv6 adoption rate globally is around 40%. As it stands, there is no locked-in time scale for deployment, however, address migration is ongoing and inevitable.

IP address shortage: What role does CGNAT play?

Amid the ongoing IPv6 deployment, providers have been harnessing the capabilities of CGNAT as something of a transitory measure. In this respect, it has helped shore up the limited remaining allocations of IPv4 addresses.

CGNAT is a technology that paves the way for providers to share a single public IP address with multiple customers. It functions in a manner similar to the way in which a router allows a range of devices on the one network to share the one public IP address.

While it is not a long-term solution, CGNAT has proven very effective in navigating the issues involved with IP address depletion. All internet users will eventually be moved over to IPv6 addresses. However CGNAT allows for a staged deployment over a longer period of time.

Google data shows that IPv6 adoption in New Zealand is a touch under 18% (as of October this year). Given the scarcity of IPv4 addresses, this indicates that many providers are using CGNAT ahead of a more widespread IPv6 rollout.

How CGNAT could impact your online activities

Most internet users on a CGNAT connection won’t notice any change when it comes to their day-to-day online activities. It simply means that when you connect to the internet, your provider will assign your router a shared public IP address.

However, if you require a publicly accessible IP address, there are some services that may be impacted, including:

• Hosting online games.
• Hosting servers, such as website and email servers
• Remotely accessing a home network, such as a computer
• Remotely accessing smart home technology, such as smart security cameras
• Accessing a secure network that requires a specific IP address

If you do use the internet for any of these activities and are experiencing issues, you’ll need to initially confirm that you are on a CGNAT connection.

As we look at below, there are a number of actions you can take to get around some of the potential issues related to this.

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How to tell if you are on a CGNAT connection

As a first stop, it will be best to check out your provider’s FAQs webpage. Chances are they will have some information on their use of CGNAT and broader approach to IPv6 deployment, along with a rundown of potentially impacted services.

If this doesn’t help, it will be worthwhile getting in touch directly with your provider. They will be able to provide you an overview of their current services and potential workarounds to CGNAT issues (see the following section).

It’s important to note that there is no uniform approach to the use of CGNAT across different providers. With this in mind, if you are looking for a new provider and believe it could present an issue, it will be important to confirm whether CGNAT is used prior to signing up.

Meanwhile, it could be that any issues you are experiencing are related to something else, and your provider may be able to provide you with insight into this and options for resolution.

How to solve potential CGNAT-related issues

The best way to avoid potential issues is to confirm with a provider if they use CGNAT technology prior to signing up. As advised above, there are a number of online activities it could impact, and it will be best to establish if there will be any issues with a specific service.

However, given the evolving nature of IPv6 adoption, if you find yourself in a situation where you are experiencing issues, there are a number of potential actions you can take:

• Opt out – will your provider allow you to opt out of using a CGNAT connection? It will be worthwhile confirming your provider’s policy on this
• Static IP – many providers offer a static IP (a dedicated IP address that will resolve CGNAT-related issues) for a monthly fee
• Change providers – if it comes down to it, and your current provider does not allow you to opt out or offer a static IP address, you may need to seek out an another provider.

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About the author of this page

This report was written by Canstar author Martin Kovacs. Martin is a freelance writer with experience covering the business, consumer technology and utilities sectors. Martin has written about a wide range of topics across both print and digital publications, including the manner in which industry continues to adapt and evolve amid the rollout of new technologies.