What Happens When IPv6 Becomes Mandatory for All Users

What Happens When IPv6 Becomes Mandatory?

For years, IPv6 has been “the future of the internet,” while IPv4 has stubbornly remained the present. But at some point, IPv6 will stop being optional and become effectively mandatory for full connectivity. That doesn’t mean IPv4 disappears overnight, but it does mean that services and networks that don’t support IPv6 will be at a serious disadvantage.

So, what actually happens when IPv6 becomes mandatory, and what should ISPs, hosting providers, and businesses expect?

What “IPv6 Becomes Mandatory” Really Means

In practice, IPv6 will become mandatory in stages, not via a single global switch:

• Major content platforms and CDNs may require IPv6 for optimal routing.
• Large ISPs and mobile carriers may offer IPv6-only access with translation for legacy IPv4.
• Some regions, regulators, or industry standards may mandate IPv6 support for public services.

At that point, if your infrastructure is still IPv4-only, you’ll need workarounds (NAT64, proxies, relays) just to reach parts of the modern internet. IPv6 support will be a baseline capability, not an advanced feature.

Impact on ISPs and Network Operators

For ISPs and backbone providers, mandatory IPv6 changes the default design assumptions:

• IPv6 routing and peering moves from “nice to have” to core infrastructure.
• New customer connections are likely provisioned IPv6-first, with IPv4 provided via CGNAT or translation.
• Network monitoring, DDoS protection, and security tools must all be fully IPv6-aware.

Operators who delay IPv6 deployment risk:

• Higher costs from expanding CGNAT for dwindling IPv4 space.
• Performance issues occur as more traffic squeezes through legacy IPv4 layers.
• Customer churn occurs when users experience better performance on IPv6-ready competitors.

Impact on Businesses, Apps, and Websites

When IPv6 is effectively mandatory, businesses that have not prepared will feel it quickly:

• Websites that are IPv4-only may load more slowly or be unreachable from some IPv6-only networks.
• APIs and SaaS platforms without IPv6 support may fail for customers on mobile or modern ISPs.
• VPNs, remote access, and IoT deployments may struggle to operate across IPv6-only environments.

On the upside, organizations that embrace dual-stack early will:

• Reach more users reliably, wherever they connect from.
• Face fewer surprises as carriers shift traffic toward IPv6.
• It is viewed as more modern and technically aligned with the future internet.

What Happens to IPv4 and Address Leasing?

Even when IPv6 is mandatory for reachability, IPv4 will still exist for a long time:

• Legacy applications and devices will continue to depend on IPv4.
• Many enterprise networks will run dual-stack (IPv4 + IPv6) for years or decades.
• IPv4 address space will still be needed for compatibility, regional policies, and specific use cases.

However, as IPv6 usage rises, IPv4 roles shift:

• The primary growth layer becomes IPv6; IPv4 focuses on compatibility.
• Businesses may decide it’s smarter to lease IPv4 blocks rather than buy at high market prices.
• Clean, reputation-safe IPv4 space stays valuable for email, certain B2B integrations, and legacy endpoints.

About IPv4Hub.net

This is exactly where IPv4Hub.net fits into the transition. As IPv6 adoption grows, IPv4Hub.net helps companies maintain a stable, clean IPv4 presence as they modernize. The platform specializes in leasing reputation-checked IPv4 blocks such as /24, /23, and /21 ranges so bu, so businesses don’t have to fight with polluted or blacklisted space. Each subnet is reviewed for blacklist status, routing history, and registry accuracy before being offered. IPv4Hub.net then matches organizations with the right block size and region for hosting, VPN, SaaS, or ISP workloads, and provides transparent, human-guided leasing instead of risky automated allocation. That lets you maintain reliable IPv4 connectivity while you roll out IPv6 across your network.

Technical Changes You Can Expect

When IPv6 becomes mandatory, several technical patterns will become mainstream:

• Dual-stack everywhere: Servers, load balancers, APIs, and DNS all run IPv4 and IPv6.
• AAAA records by default: Every important hostname has both A (IPv4) and AAAA (IPv6) records.
• IPv6-only segments: Some networks, especially mobile and IoT, become IPv6-only with NAT64/DNS64 to reach IPv4.
• IPv6-first monitoring and security: Logging, SIEM, WAF, and IDS/IPS tools must handle IPv6 traffic as a first-class citizen.

Teams will need skills in IPv6 addressing plans, Neighbor Discovery, SLAAC vs DHCPv6, and IPv6 security best practices.

How to Prepare Before IPv6 Is Mandatory

If you wait until IPv6 is mandatory, you’re already late. Start now:

1. Enable dual-stack on public-facing services (web, APIs, mail).
2. Work with your ISP to obtain and route IPv6 prefixes.
3. Update DNS with AAAA records and test from IPv6-only networks.
4. Audit applications and devices for IPv6 readiness and upgrade where needed.
5. Train your network and ops teams on IPv6 design, troubleshooting, and security.

At the same time, stabilize your IPv4 position with clean, well-managed address space leased or acquired through trusted partners like IPv4Hub.net.

When IPv6 becomes mandatory, the internet won’t suddenly break, but the gap between IPv6-ready and IPv4-only organizations will widen quickly. IPv6 will become the default path for users, while IPv4 shifts into a compatibility role that still needs to be handled carefully.

By planning for dual-stack, investing in IPv6 skills, and managing IPv4 intelligently through services like IPv4Hub.net, you can turn this shift from a risky disruption into a strategic advantage for your network and your business.