Case study


CBS out in front with IPv6 example


An independent body, Statistics Netherlands (CBS) is responsible for collecting and processing statistical data for use by policymakers, scientific research and the public at large. In years to come, web access to this data may be hampered as the stock of IPv4 addresses runs out, prompting the transition to IPv6 addressing. To ensure long-term reliable online access to public data and services, the Dutch government ordered all public government organisations to be IPv6-proof by the end of 2013. CBS was first to take up the challenge.


To assess the impact of the government’s decree on its infrastructure, CBS had an inventory study carried out, resulting in clear advice: ensure IPv6 compliance at the edge of the CBS network by placing a router and DNS server supporting both IPv4 and IPv6 address stacks. Meanwhile, gradually migrate internal infrastructure, operating systems and applications to IPv6, while phasing out the old IPv4 environment.

This hybrid approach protects investments while ensuring that IPv6-only clients and services will experience no problems when accessing the website. CBS decided to follow this advice and teamed up with BT and an external specialist to devise a project plan. “IPv6 migration affects the entire IT environment and is a massive task, but we decided to keep it simple and split it up in manageable bits, starting where we need it most―at the edge of the network.” says John van Rooijen, Technical Manager ICT Infrastructure at CBS.

Using the BT Internet Connect Global service, BT implemented a new managed internet router, made IPv6 ready by configuring a dual-stack protocol on it. CBS obtained its own IPv6 address block, allowing it to work out a future proof number plan on its DNS server. The CBS firewall translates IPv6 addresses into the internal IPv4 addresses of existing systems and applications.


CBS is now the first Dutch public body supporting IPv6 web access and is gradually rolling out IPv6 throughout its IT internal environment. “Achieving IPv6 compliance seemed somewhat intimidating when we embarked upon this journey, but thanks to the support of BT and external experts it proved all very doable.” says John van Rooijen.

After setting up external IPv6 access, CBS is now adding IPv6 connectivity to specific systems and applications on a project-by-project basis. This way it can keep control and maintain an overview, while protecting historic investment and replacing systems and applications at its own pace.

“As our internet access provider, BT offered great help by smoothly configuring the dual-stack BT managed router,” concludes John van Rooijen, “and it also published our new IPv6 address block on the internet so that ISPs around the world know where to find us. Our IPv6 journey has been a very interesting and rewarding experience.”

Core Services

  • BT Internet Connect global


Case study

CBS case study

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