I am pleased to announce the publication of BITAG’s report on Large Scale Network Address Translation, or, as it is called among us engineers, Large Scale NAT or LSN. I believe this technical report represents a valuable contribution that enables technical and non-technical individuals alike to better understand a particular management technique that is being used to ease the transition from IPv4 to IPv6. It also further demonstrates the constructive role that BITAG can play in the Internet ecosystem. IPv4 and IPv6 refer to addressing schemes that allow machines (computers) to find each other when a user types in something like “www.bitag.org.” The shift from IPv4 to IPv6 is motivated by the rapid growth in the Internet and the associated increasing scarcity of traditional IPv4 addresses. These two addressing techniques must coexist for some time as it is impractical to do a flash-cut change from the older format to the new IPv6 format.
Large Scale NAT (LSN) is just one technique being used to facilitate the transition from IPv4 to IPv6 and to reduce any frictions caused by the necessary coexistence of the two addressing systems. This report is the second report produced by BITAG’s Technical Working Group (TWG). Our first report dealt with DNS Whitelisting, which is another technique used to address the IPv6 transition.
Simply stated, LSN allows a large number of IPv4 devices to share a single IPv4 address. This technique has existed for some time in local or private networks to, for example, allow a company’s IT department to rely upon and manage its own private address space but it is now being adopted on a widespread basis by network operators as a means of postponing the ultimate exhaustion of their IPv4 address space.
What makes this topic especially interesting from my perspective as Executive Director of BITAG is that it is likely to affect many different categories of players in the Internet ecosystems: ISPs, end users, application providers, equipment vendors, content delivery networks, and third parties such as law enforcement agencies. BITAG was established on a multi-stakeholder basis to address changes in network management and other techniques that could have wide-ranging (and potentially negative) impacts on end users and the applications that they rely upon. By providing an overview of how network operators plan to use LSN and how the technique could impact these and other interest groups, I believe that this Report will both (a) help stakeholders prepare for the wider implementation of LSN and to take actions that minimize the impact on end users and applications and (b) help inform policymakers and regulators of the motivations and trade-offs for the deployment of this technology. More fundamentally, I hope this Report will help smooth the transition to IPv6 and more generally help to reduce or preclude friction and/or conflict surrounding use of this technique among stakeholders. This is important in terms of BITAG’s overall mission because some observers have expressed the concern that Large Scale NAT could be abused by parties for anti-competitive, discriminatory, or other non-technical purposes.
The LSN report, including its recommendations, can be found at: http://www.bitag.org/documents/BITAG_TWG_Report-Large_Scale_NAT.pdf.