June 6th, 2012 was World IPv6 Day. On that day several major ISPs, equipment manufacturers and website operators committed to deploy IPv6 for their products and services. Yet, over ten years later there are estimates that only about 40% of websites are reachable via an IPv6 address. 

This continues to be an issue for broadband providers, and that’s even the case for those who are new to the game. A new provider might think they can launch their service with an all-IPv6 network and not have to worry about IPv4, but that’s not how it works. IPv6 is not backward compatible with IPv4. Even if a provider’s network is all IPv6 from the very start, every subscriber still must have access to a publicly routable IPv4 address so that they can reach any IPv4-only websites on the Internet. And that IPv4 content will remain there for years to come. 

Dual Stack Deployment for IPv4 Compatibility

If you are launching service for the first time on an IPv6 network you can do a dual-stack implementation where you provide your customers access to both an IPv6 address and an IPv4 address. If the content they are trying to reach is IPv4 only, their system will automatically use their IPv4 address. If the website is on an IPv6 network, it will use their IPv6 address. 

One way to deploy dual stack is to assign every subscriber their own public IPv4 address, but this can get very costly over time. IPv4 addresses are expensive, having varied from $40 to $60 per address recently. That winds up being an additional cost for every subscriber you add. 

With the distribution of millions of dollars in funding from the Broadband Equity, Access and Deployment (BEAD) program, new and existing operators will be launching broadband service in previously unserved and underserved areas. In those areas there will be a lot of pent-up demand from customers who have been living with slow Internet service, which will mean a quickly growing subscriber base right from the start. 

A better solution than buying IPv4 addresses for every subscriber is to deploy Carrier Grade NAT (CGNAT) with NAT64 and DN64 enabled. With CGNAT you don’t need an IPv4 address for every subscriber. NAT64 will do a translation between a subscriber’s IPv6 address and a public IPv4 address that is shared among multiple customers. DNS64 is used to translate the IPv4 A record of the website into an IPv6 AAAA record (quad A record). 

What can that mean to your bottom line?  With CGNAT you can oversubscribe every IPv4 address 128 times or more. As an example, if you expect to have 1,200 subscribers after your first year in business, you’ll only need ten IPv4 addresses that first year with a 128:1 oversubscription ratio. Compare that to paying for 1,200 addresses at $40 each ($48,000). Yes, there is the upfront cost of purchasing CGNAT software and equipment, but it doesn’t take long for the cost of IP addresses to exceed the cost of deploying CGNAT. In the scenario above, the payback would be well under a year. In addition, without CGNAT your IPv4 expenses will continue to climb with every subscriber who signs up for your service. 

We can help. ZCorum offers an affordable, software-based CGNAT solution that is easily scalable for providers of all sizes. Unlike some CGNAT solutions that are deployed on expensive, proprietary hardware, you can deploy our virtual CGNAT solution on standard, off-the-shelf servers sized for your current needs. And, we offer flexible licensing that will grow with you. You can learn more about our virtual CGNAT solution here, or feel free to contact us for more information and pricing.