Outline

•  Background

•  IETF activities

•  Solutions & problems

• Next steps

Time

IPv4 Free Pool

Size of the Internet

IPv6 Deployment

The Plan

Time

IPv4 Free Pool

Size of the Internet

IPv6 Deployment

The Reality Today

?

Background

•  Does this cause us to reconsider whether our IPv6 deployment and transition toolbox is adequate?

•  Or the need for new tools to deal with the pain of IPv4 address shortage?

•  The situation with NAT-PT

•  Input from the service providers and corporate network managers

•  IETF discussions from 2007

This Is Important!

•  The way we deploy IPv4 NATs changes as there is less address space

•  We cannot deploy IPv6 in all situations where we would like to

•  I see many potential future outcomes, some of them bleak

•  Is there something that we can do to help provide better solutions and to help IPv4-IPv6 co-existence and IPv6 adoption?

State of the Art •  This is not a claim that the existing tools should no

longer be used – for instance, Dual Stack with an IPv4 NAT is still what most networks would likely want to use

•  Similarly, existing tunneling mechanisms for IPv6 transition continue to be valid

•  Focus is on new situations, such as when a NAT does not even have one address, or when RFC 1918 space runs out

•  Avoid the search for a silver bullet

Recent IETF Activities

•  Several discussions in Dublin

•  An interim meeting in Montreal

•  New charter for SOFTWIRE WG

•  Proposed new charter for BEHAVE WG

Montreal Outcome •  A well attended interim meeting in Montreal on

October 1st-2nd

•  Focused on improved IPv4 NATs, tunneling to solve RFC 1918 shortage, and IPv4 – IPv6 translation

•  Strong consensus that we need we need both tunneling and translation based solutions to address different scenarios

•  A better understanding of how different solutions

Solutions and Problems

•  Home gateway and service provider router tunnel IPv4 over IPv6

•  Often combined with a NAT on the provider router to share one address

•  IPv6 to home gateways as a side effect

Dual-Stack Light – Running Out of RFC 1918 Space�

•  Each subscriber gets only a fraction of a public address; a port range

•  Can be implemented in various ways: an extension of the tunneling approach, mapping port ranges to IPv6 (A+P), ...

•  Again, as a side-effect gateways get IPv6

Shared public address, separate port ranges

NAT stays here Port-based forwarding here

Port Borrowing – Public IPv4 Address Shortage

Translation – IPv6 Hosts Reaching IPv4 Hosts

•  An example application is IPv6 hosts connecting to IPv4-only servers

•  E.g., Windows 7 Direct Access

•  Enables unilateral IPv6 deployment

•  Currently uses NAT-PT,

IPv6 host

IPv4 servers

More on Translation

•  Work will address four cases: connecting a specific IPvX-only network to the IPvY Internet, with initiation on either side

•  IPv6 access to a set of IPv4 servers

•  IPv6-only branch office connecting to IPv4 Internet

•  IPv4 access to a set of IPv6 servers

•  The last IPv4 holdout accessing the IPv6 Internet

More on Translation 2

•  Documents under development include framework, packet translation, state maintenance, and DNS parts

•  Challenges include DNSSEC and preventing dual stack hosts accidentally selecting a path through a translator

•  The two ways to improve over NAT-PT: simply a better specification and focusing on constrained scenarios

•  As an example, no DNS tricks needed when

Next Steps •  Please provide feedback

•  Here, on the list, or in the IETF meetings

•  Upcoming meeting in Minneapolis

•  Interim meetings in Malta (Jan 20-22)‏

•  Progress the specifications from BEHAVE and SOFTWIRE

•C

Further Reading http://trac.tools.ietf.org/area/int/trac/wiki/v4v6interim http://tools.ietf.org/html/draft-arkko-townsley-coexistence http://tools.ietf.org/wg/softwire http://www.ietf.org/html.charters/softwire-charter.html http://tools.ietf.org/wg/behave http://www.ietf.org/mail-archive/web/behave/current/msg04569.html http://www.ietf.org/mail-archive/web/behave/current/msg04554.html http://tools.ietf.org/id/draft-durand-softwire-dual-stack-lite http://tools.ietf.org/id/draft-bagnulo-behave-nat64 http://tools.ietf.org/id/draft-bagnulo-behave-dns64-00.txt http://tools.ietf.org/id/draft-baker-behave-v4v6-framework-00.txt http://tools.ietf.org/id/draft-baker-behave-v4v6-translation-00.txt RFC 4213 RFC 2766 RFC 4966