In March 2020, the U.S. Government Office of Management and Budget (OMB) released a draft memo outlining a required migration to IPv6 only. Memorandum M-21-07 was made official on November 19, 2020. Among other things, this memo mandates that 80% of IP-enabled assets on Federal networks are operating in IPv6-only environments by the end of FY 2025.

ESnet is in the process of planning this transition now, to ensure that we provide our users with the support and resources they need to continue their work uninterrupted and unimpeded by the transition. Practically speaking, this means for ESnet that by 2025, all of our nodes will be transitioned to IPv6 address space, and we will not support dual-stacking with IPv4 and IPv6 addresses. 

Transitioning to an IPv6-only network has been over a quarter-century in the making for ESnet.  Here’s a look back at our history with IPv6

IPv6: Past and Present

ESnet’s history of helping to develop, support, and operationalize new protocols begins well before the advent of IPv6.  

In the early 1990s, Cathy Aronson, an employee of Lawrence Livermore National Laboratory working on ESnet, helped establish a production implementation and support plan for the Open Systems Interconnect (OSI) Connectionless-mode Network Service (CLNS) suite of network protocols. Crucially, Aronson developed a scalable network addressing plan that provided a model for the utilization of the kinds of massive address spaces that OSI CLNS and, later, IPv6 would come to use. CLNS itself was a logical progression from DECnet which had been embraced and supported by ESnet’s precursors (MFEnet and HEPnet).  

As the IPv6 draft standard (RFC2460) developed in the 1990s, ESnet staff created an operational support model for the new protocol. The stakes were high; if IPv6 were to succeed in supplanting IPv4, and prevent the ill effects of IPv4 address exhaustion, it would need a smooth roll-out. Bob Fink, Tony Hain, and Becca Nitzan spearheaded early IPv6 adoption processes, and their efforts reached far beyond ESnet and the Department of Energy (DOE).  The trio were instrumental in establishing a set of operational practices and testbeds under the auspices of the Internet Engineering Task Force–the body where IPv6 was standardized–and this led to the development of a worldwide collaboration known as the 6bone.  6bone was a set of tunnels that allowed IPv6 “islands” to be connected, forming a global overlay network.  More importantly, it was a collaboration that brought together commercial and research networks, vendors, and scientists, all with the goal of creating a robust internet protocol for the future.

Not only were Fink, Hain, and Nitzan critical in this development of what would become a production IPv6 network (their names appear on a number of IETF RFCs), they would also spearhead the adoption of the protocol within ESnet and DOE. In the summer of 1996, ESnet was officially connected to the 6bone; by 1999, the Regional Internet Registries had received their production allocations of IPv6 address space. Just one month later, the first US allocation of that space was made–to ESnet.  ESnet has the distinction of being the first IPv6 allocation from ARIN – assigned on August 3, 1999, with the prefix 2001:0400::/32. 

Nitzan continued her pioneering work, establishing native IPv6 support on ESnet, and placing what we believe was the first workstation on a production IPv6 network. This was part of becoming the first production network in North America to adopt IPv6 in tandem with IPv4 via the use of an IPv6 “dual-stack.” As US Government requirements and mandates developed in 2005, 2012, and 2014, the ESnet team met these requirements for increased IPv6 adoption, while also providing support and consultation for the DOE community. 

Although Aronson, Fink, Hain, and Nitzan have all moved on from ESnet, a new generation of staff continued the spirit of innovation and early adoption. In the early 2010s, ESnet’s internal routing protocols were consolidated around the use of multi-topology Intermediate System to Intermediate System or IS-IS. This allowed for the deployment of flexible and disparate IPv4 and IPv6 topologies, paving the way for the creation of IPv6-only portions of ESnet, allowing the use of optimized routing protocols for the entire network.  ESnet’s acquisition strategy has long emphasized IPv6 support and feature parity between IPv4 and IPv6.  

All IPv6: Switching over, and the future

As ESnet moves into ESnet6, it is well-positioned to build and expand an IPv6-only network, while retaining legacy support for IPv4 where needed. ESnet will soon finish a two-year project to switch our management plane entirely over to IPv6. 

For our customers and those connected to us, here’s what this means:

• ESnet will be ready, willing, and able to support connectors, constituents, and partners in their journey to deploying IPv6-only across our international network. 
• ESnet planning and architecture team members have been included in the Department of Energy Integration and Product Team (DOE IPT) for migration to IPv6-only, and are supporting planning and documentation efforts for the DOE Complex.
• We look forward to supporting our customers and users, as we all make this change to IPv6 together.