Telstra Broadband CGNAT in Australia: Key Use Cases and How Does it Work

Telstra, one of Australia’s leading telecommunications providers, often uses Carrier-Grade Network Address Translation (CGNAT) as part of its broadband service infrastructure. If you’re considering Telstra broadband or already using it, understanding CGNAT is crucial. CGNAT impacts aspects of internet connectivity and online activities for many residential users, so knowing how it works and the key use cases will help you maximize your online experience.

What is CGNAT?

CGNAT (Carrier-Grade NAT) is a solution used by internet providers to handle the shortage of public IP addresses. With the increasing number of devices online, there aren’t enough unique IP addresses for everyone. Instead of giving each customer their own public IP, ISPs use CGNAT to let multiple users share the same public IP address.

Here’s how it works:

When you connect to the internet at home, your router assigns private IP addresses to your devices (like your phone or laptop) and turns them into one public IP when you access the internet. CGNAT takes this a step further by grouping several customers under one public IP at the ISP level. This saves IP addresses but can create issues for certain activities, like gaming or hosting a server, where a dedicated public IP is needed.

Learn More: CGNAT Port Forwarding

What is CGNAT in Telstra Broadband?

CGNAT, or Carrier-Grade Network Address Translation, allows internet providers to allocate a single IP address to multiple devices on the network. This shared IP approach is commonly adopted by internet service providers (ISPs), such as Telstra, to address the shortage of IPv4 addresses. Rather than giving each device its own unique public IP address, CGNAT enables multiple users to share one IP, conserving resources while maintaining internet access.

How CGNAT Works in Telstra Broadband in Australia

In Telstra’s broadband infrastructure, CGNAT routes your device’s traffic through a shared IP address. This setup works well for most everyday browsing, streaming, and social media. However, if you’re doing something that requires a unique IP address, such as hosting a server or remote device access, CGNAT can be limiting. Let’s break down its primary use cases to understand where it’s beneficial—and where you may run into challenges.

If you’re experiencing issues with Telstra’s CGNAT (Carrier-Grade Network Address Translation) and need to get around it, here are some straightforward steps to consider:

1. Request a Public IP Address from Telstra

• The easiest solution is to contact Telstra customer support and request a public IP address. Some Telstra plans or business packages may include this option, or it could be offered for a small fee.
• A public IP address allows you to connect directly to the internet without CGNAT limitations, which is ideal for activities like remote device access, hosting servers, or using certain online games.

2. Use a VPN (Virtual Private Network)

• A VPN can route your connection through an external server, effectively getting around CGNAT for certain applications.
• Some VPNs allow port forwarding, which can improve connections for remote access and online gaming. Look for a VPN service that offers this feature if it’s essential for you.
• Simply install and connect to the VPN app on your device, and your internet traffic will go through the VPN server instead of Telstra’s CGNAT.

3. Consider Port-Forwarding with VPN or Cloud Service

• For users needing access to specific devices or services on their network, using a VPN or cloud-based service with port-forwarding capabilities can be effective.
• Set up port forwarding within the VPN or cloud service settings, enabling external access to devices on your network. This works well for accessing home security cameras or smart devices remotely.

4. Switch to an Alternative ISP

• If none of the options above work or seem too complex, consider switching to an ISP that doesn’t use CGNAT or offers easy access to a public IP.
• Some smaller ISPs may not use CGNAT for residential customers or can provide more flexible networking options.

Each option has pros and cons depending on your specific needs and technical skills, but these are the most practical steps to get around CGNAT restrictions.

Key Use Cases for Telstra Broadband CGNAT

1. Everyday Browsing and Streaming For most users, CGNAT won’t impact routine activities like web browsing, watching YouTube, or scrolling social media. These common activities don’t require a dedicated IP address. Telstra’s CGNAT-enabled broadband supports stable connections and fast load times, even when shared across multiple users. So, if your main focus is surfing the web, CGNAT likely won’t be an issue.
2. Online Gaming Online gaming has mixed results with CGNAT. While Telstra’s CGNAT can support multiplayer games that don’t require a unique IP address, some games and services may run into connection issues. For example, certain games that require peer-to-peer (P2P) connections or host servers may encounter difficulties under CGNAT, potentially leading to lag or disconnects. If you’re an avid gamer, this is worth considering, as some workarounds (such as using a VPN or requesting a static IP) might be needed.
3. Remote Access and Security Systems Users who rely on remote access to home devices, such as security cameras, smart home hubs, or home servers, might experience limitations with CGNAT. Since devices under CGNAT share an IP address, accessing them remotely can be challenging without an individually assigned IP. For those who frequently use these devices, Telstra’s CGNAT may not offer the flexibility you need. Solutions like a VPN with port forwarding or requesting a public IP address can help resolve this.
4. VoIP and Video Conferencing VoIP services and video conferencing platforms generally work well with Telstra’s CGNAT-enabled broadband, as these services don’t require a dedicated IP address. However, high-volume users or those needing advanced configurations may notice connectivity or quality issues due to CGNAT’s shared network structure. Professionals who rely heavily on video conferencing might want to monitor performance to ensure CGNAT’s impact is minimal.
5. Hosting Servers Hosting servers—whether for gaming, file sharing, or other purposes—presents one of the biggest challenges under CGNAT. Since Telstra’s CGNAT structure doesn’t assign individual public IPs to each user, it restricts your ability to set up and manage home servers. Users looking to run a home server may need to opt out of CGNAT if possible or choose alternative methods like using third-party hosting services.

Benefits of CGNAT in Telstra Broadband

While CGNAT presents some limitations, it also offers advantages for many Telstra broadband users:

• Improved IPv4 Resource Management: CGNAT helps Telstra conserve IPv4 addresses, ensuring more users have access to the internet without disruption.
• Streamlined Network Maintenance: By managing a smaller pool of public IPs, Telstra can improve its network’s efficiency and reliability.
• Enhanced Security: CGNAT adds an extra layer of security, as external requests won’t directly reach individual devices.

Potential Downsides of Telstra Broadband CGNAT

While CGNAT meets the needs of many, it may not be ideal for every user:

• Limited Remote Access: Those who need remote device access or self-hosted servers may face limitations without a public IP.
• Gaming and Peer-to-Peer Limitations: CGNAT can impact connection stability for gaming and some P2P services.
• Troubleshooting Complexity: Shared IP issues can make troubleshooting more complex, particularly if there are IP conflicts within the shared network.

How to Check if Telstra Broadband Uses CGNAT in Australia

To determine if your Telstra connection is under CGNAT, you can use any of the following methods:

Method 1: Check the Router’s WAN IP Address

1. Open a web browser and enter your router’s IP address into the address bar.
2. Enter your username and password to access the dashboard.
3. Navigate to the status screen on the dashboard.
4. Find the section labeled as ‘WAN IP’ or a similar term, which might vary based on the router model.
5. Examine the IP address assigned to the router’s WAN interface.
6. If this IP address falls within the range of 100.64.0.1 to 100.127.255.254, your connection is likely behind CGNAT. This IP range is designated for CGNAT usage.

Related Read: Port Forwarding on a dedicated router

Method 2: Compare WAN IP and Public IP Address

1. Follow the steps from Method 1 to find and note down the WAN IP address from your router’s dashboard.
2. Open a new tab in your web browser
3. Search for “what is my IP address” and press Enter.
4. Remember the public IP address displayed by the search results.
5. If the WAN IP and the public IP address are different, it indicates that your ISP is using CGNAT.
6. If they match, your connection likely has a direct public IP address, meaning it is not behind CGNAT.

Related Guide: How to Check if your ISPs perform CGNAT

How to Get Around CGNAT with PureVPN

CGNAT (Carrier-Grade NAT) can cause issues with certain online activities like gaming, hosting a server, or accessing your home network remotely. PureVPN offers a way to avoid CGNAT by providing you with a secure and direct connection to the internet using a public IP address.

Here’s how to get around CGNAT with PureVPN:

1. Sign Up for PureVPN

First, you need to sign up for a PureVPN account. We offer various subscription plans, so choose the one that suits your needs.

2. Download/Install PureVPN

PureVPN is available on multiple platforms including Windows, Mac, Android, iOS, and routers. Download and install the app or configure PureVPN on your Telstra or any other router.

3. Log In to PureVPN

Once installed, log in with the credentials you created during the signup process.

4. Connect to a Server

Open the PureVPN app and select a server from a location of your choice. PureVPN will route your traffic through this server, which has a public IP address. This effectively avoid CGNAT, as your connection will no longer rely on the shared IP address provided by your ISP.

5. Enable Port Forwarding (Optional)

If you need to host servers or access devices remotely, PureVPN also offers port forwarding. You can enable this feature directly in your PureVPN account settings. This helps you manage specific ports for gaming, torrenting, or running applications that require direct access.

6. Verify Your Connection

After connecting to a PureVPN server, verify that you’re no longer behind CGNAT. You can use online tools to check your IP address and confirm that it’s a public IP.

Benefits of Using PureVPN to Avoid CGNAT

• Improved online gaming: Reduce lag and connect to servers directly.
• Remote access: Easily access your home network or devices from anywhere.
• Enhanced privacy: PureVPN encrypts your connection, offering additional security.

By following these steps, you can avoid CGNAT using PureVPN and enjoy a more direct, unrestricted internet experience.

Final Thoughts

Telstra’s implementation of CGNAT enables greater accessibility to internet resources while supporting most everyday digital activities seamlessly. However, understanding its capabilities and limitations will help you make the most of your broadband connection. If CGNAT limitations interfere with your digital needs, consult Telstra for solutions such as a static IP or consider third-party options for specific requirements. By aligning your internet usage with the right network setup, you can maximize your Telstra broadband experience with confidence.