BITAG’s Large Scale NAT Report Published

(Mar. 7, 2012)
The Internet is running out of IPv4 addresses. A successor address format, IPv6, has been developed to support as many devices as can conceivably be connected to the Internet for the foreseeable future but the IPv6 transition will take several years to be completed. IPv4 and IPv6 will thus need to co-exist until the demand for IPv4 services diminishes.  Network operators are employing a variety of techniques to extend the life of IPv4 addressing given the specter of a long term IPv6 transition. Large Scale Network Address Translation (also known as “Large Scale NAT” or “LSN”) is one such technique.  LSN equipment allows a large number of IPv4-enabled end devices to share a single public IPv4 address. Network Address Translation (“NAT”) functionality has long existed in local/private networks to help network operators manage their network addresses using private address space but network operators now contemplate using it on a widespread basis.

BITAG undertook review of LSN because IP address sharing is a key tool for extending the life of IPv4 during the transition to IPv6.  LSN is likely to affect many players in the Internet ecosystem: ISPs, end users, application providers, equipment vendors, content delivery networks, and third parties such as law enforcement agencies. BITAG’s review analyzes the LSN and provides an overview of how network operators plan to use it and how LSN could impact these other interest groups.  BITAG believes that a broad understanding of LSN and its implications will: (1) help stakeholders to prepare for actions that minimize the impact on end users and applications; (2) inform policymakers and regulators of the motivations and trade-offs for the deployment of this technology; (3) accelerate the transition to IPv6; and (4) more generally help to reduce or preclude friction and/or conflict surrounding use of this technique among stakeholders, as some have argued that Large Scale NAT could be abused by parties for anti-competitive, discriminatory, or other non-technical purposes. [PDF]
 
Large Scale NAT in More Depth.
The Internet is running out of IPv4 addresses. A successor address format, IPv6, has been developed to support as many devices as can conceivably be connected to the Internet for the foreseeable future but the IPv6 transition will take several years to be completed. IPv4 and IPv6 will thus need to co-exist until the demand for IPv4 services diminishes.  Network operators are employing a variety of techniques to extend the life of IPv4 addressinggiven the specter of a long term IPv6 transition. Large Scale Network Address Translation (also known as “Large Scale NAT” or “LSN”) is one such technique.  LSN equipment allows a large number of IPv4-enabled end devices to share a single public IPv4 address. Network Address Translation (“NAT”) functionality has long existed in local/private networks to help network operators manage their network addresses using private addressspace but network operators now contemplate using it on a widespread basis.
BITAG undertook review of LSN because IP address sharing is a key tool for extending the life of IPv4 during the transition to IPv6.  LSN is likely to affect many players in the Internet ecosystem: ISPs, end users, applicationproviders, equipment vendors, content delivery networks, and third parties such as law enforcement agencies. BITAG’s review analyzes the LSN and provides an overview of how network operators plan to use it and how LSN could impact these other interest groups.  BITAG believes that a broad understanding of LSN and its implications will: (1) help stakeholders to prepare for actions that minimize the impact on end users and applications; (2) inform policymakers and regulators of the motivations andtrade-offs for the deployment of this technology; (3) accelerate the transition to IPv6; and (4) more generally help to reduce or preclude friction and/or conflict surrounding use of this technique among stakeholders, as some haveargued that Large Scale NAT could be abused by parties for anti-competitive, discriminatory, or other non-technical purposes.
Additional Information about BITAG and its Technical Review Process.
About BITAG. BITAG is a non-profit, multi-stakeholder organization focused on bringing together engineers and technologists in a Technical Working Group (TWG) to develop consensus on broadband network management practices and other related technical issues that can affect users’ Internet experience, including the impact to and from applications, content and devices that utilize the Internet.
BITAG’s mission includes: (a) educating policymakers on such technical issues; (b) addressing specific technical matters in an effort to minimize related policy disputes; and (c) serving as a sounding board for new ideas and network management practices. Specific TWG functions also may include: (i) identifying “best practices” by broadband providers and other entities; (ii) interpreting and applying “safe harbor” practices; (iii) otherwise providing technical guidance to industry and to the public; and/or (iv) issuing advisory opinions on the technical issues germane to the TWG’s mission that may underlie disputes concerning broadband network management practices.
BITAG TWG reports focus primarily on technical issues.  While the reports may touch on a broad range of questions associated with a particular network management practice, the reports are not intended to address or analyze in a comprehensive fashion the economic, legal, regulatory or public policy issues that the practice may raise.
About BITAG’s Technical Review Process. BITAG’s core substantive work is performed through its TWG, which was formed with the core principles of being: technically driven, balanced, open, efficient, independent, and flexible. The TWG reviews technical issues brought to it through Review Requests submitted by both Members and non-Members, or through a majority weighted vote of the TWG engineers themselves. Each individual Review is taken up by a Committee of the TWG that is composed of engineers and other technical experts representing a broad cross section of the Internet ecosystem. TWG Committees generally operate on a consensus basis, with backs….