Much-maligned feature being added to IPv6

Standards body weighs network address translators for next-gen Internet

IPv6 NAT proposals

For the past year, the IETF's IPv6 Operations working group has been discussing how best to develop NATs for IPv6.

The IETF first considered network address translation with IPv6 in 2000, when it created a document entitled RFC 2766, Network Address Translation - Protocol Translation (NAT-PT). NAT-PT provided a mechanism for the dynamic allocation of public IPv4 addresses for IPv6-only nodes to allow IPv6-only nodes to communicate with IPv4-only nodes.

Last year, the IETF announced that NAT-PT causes too many deployment problems and security vulnerabilities. The rationale for avoiding NAT-PT, including the fact that it leaves networks open to denial-of-service attacks, is described in RFC 4966, Reasons to Move the Network Address Translation-Protocol Translation (NAT-PT) to Historic Status.

After much debate, the IPv6 Operations Working Group in May issued a document that outlines the requirements for NATs for IPv6. This document will be sent to the IETF leadership for approval this summer, Baker said.

Also working on NATs for IPv6 are the IETF's Behavior Engineering for Hindrance Annoyance (BEHAVE) working group, which specializes in issues related to the use of NATs over the Internet, as well as the Softwires working group, which is developing tunneling and other mechanisms to ease the transition between IPv4 and IPv6.

"The work is important," says Dan Wing, chair of BEHAVE. Wing, a Cisco engineer, says BEHAVE will spend a significant amount of time at its face-to-face meeting in Dublin discussing NATs for IPv6.

The issue of NATs for IPv6 also is on the agenda for the Internet Area's open meeting in Dublin.

"We are going to evaluate NAT designs that avoid the problems described in RFC 4966," Wing says. "After the Dublin meeting, the [IETF leadership] will decide how to split the effort between the SOFTWIRE, INTERAREA, V6Ops and BEHAVE working groups."

The IETF is looking at five approaches for NATs for IPv6.

Choosing the best and simplest NAT approach for IPv6 is a priority for the IETF.

"A big concern of mine is that we'll make a NAT solution so good that no one moves to IPv6," Baker quips.

Geoff Huston, chief scientist at APNIC and an expert on IPv4 address depletion, says it's important for the IETF to develop high-quality NATs for IPv6 instead of ignoring the requirement as it did with NATs for IPv4.

"Frankly, it's a NAT-dense Internet these days, and I for one would rather see the world as it is than steadfastly maintain a position of high principle in the face of reality," Huston says. "The challenge to the IETF is whether it is prepared to shed its biases here and figure out what would makes NATs in IPv6 slightly less odious than what we did in IPv4."

Huston says NATs are useful for addressing, packet filtering and other functions. He says the real problem with NATs is that they lack standards, and that is an area where the IETF can make improvements in NATs for IPv6.

"The IETF's position of ignoring NATs some years back forced NAT software builders to exercise their own creativity when designing their version of NATs," Huston says. "This variation of NAT behavior is a far, far worse problem than NATs themselves."

Huston says NATs for IPv6 are "absolutely vital" for the transition from IPv4 to IPv6.

"Without NATs we might as well all go home, as we cannot drive through this transition process with a completely depleted IPv4 pool of addresses without a whole lot of additional NAT capability, both as traditional NATs and as protocol translating NATs," Huston says.

Join the newsletter!

Error: Please check your email address.
Rocket to Success - Your 10 Tips for Smarter ERP System Selection
Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Carolyn Duffy Marsan

Network World
Show Comments

Cool Tech

SanDisk MicroSDXC™ for Nintendo® Switch™

Learn more >

Breitling Superocean Heritage Chronographe 44

Learn more >

Toys for Boys

Family Friendly

Panasonic 4K UHD Blu-Ray Player and Full HD Recorder with Netflix - UBT1GL-K

Learn more >

Stocking Stuffer

Razer DeathAdder Expert Ergonomic Gaming Mouse

Learn more >

Christmas Gift Guide

Click for more ›

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Walid Mikhael

Brother QL-820NWB Professional Label Printer

It’s easy to set up, it’s compact and quiet when printing and to top if off, the print quality is excellent. This is hands down the best printer I’ve used for printing labels.

Ben Ramsden

Sharp PN-40TC1 Huddle Board

Brainstorming, innovation, problem solving, and negotiation have all become much more productive and valuable if people can easily collaborate in real time with minimal friction.

Sarah Ieroianni

Brother QL-820NWB Professional Label Printer

The print quality also does not disappoint, it’s clear, bold, doesn’t smudge and the text is perfectly sized.

Ratchada Dunn

Sharp PN-40TC1 Huddle Board

The Huddle Board’s built in program; Sharp Touch Viewing software allows us to easily manipulate and edit our documents (jpegs and PDFs) all at the same time on the dashboard.

George Khoury

Sharp PN-40TC1 Huddle Board

The biggest perks for me would be that it comes with easy to use and comprehensive programs that make the collaboration process a whole lot more intuitive and organic

David Coyle

Brother PocketJet PJ-773 A4 Portable Thermal Printer

I rate the printer as a 5 out of 5 stars as it has been able to fit seamlessly into my busy and mobile lifestyle.

Featured Content

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?