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Getting started with IPv6

Top Ten Ways to Get Started with IPv6

  1. Demand native IPv6 from your Internet service provider!
  2. Use the 6rd protocol with a provider like Comcast (see:
  3. Use a Tunnelbroker (
  4. Use a Windows based application from someone like
  5. Use the 6to4 protocol on a supported router (
  6. Make a VPN connection to machine or VM on a dual-stacked network
  7. Use Cisco Anyconnect to someone who has an ASA on an IPv6 network
  8. User Teredo (Shipworm) or Miredo (or don't, it's really a bad idea)
  9. Move into your friend's house where she already has it running
  10. Rely on RFC1149

In February 2011, the last of the large unused IPv4 addresses blocks have been allocated but the Internet continues to grow despite the imminent exhaustion of address space.  In order for growth to continue  uninterrupted, the Internet and all of its users will have to make a transition to IPv6, a protocol which provides a practically unlimited number of endpoint addresses.  IPv6 has already been deployed in many  large Cisco networks, but the depletion of IPv4 addresses has served to inspire greater IPv6 adoption; a number of organizations are outlining  ambitious transition plans.

Although not all service providers offer IPv6, there are a number  of options to run IPv6 in a small network so that you can start to get  experience with this new protocol.  A number of “tunnel brokers” will  offer early adopters a block of 264 addresses (a “/64 prefix”) or even 280 addresses (a “/48 prefix”), just for the asking.  To put that into  perspective, the smaller of those two blocks would accommodate a  complete copy of the entire internet, even if every single node on that  copy had another copy of the entire internet behind it.  There are 18.4 quintillion usable static addresses in a “/64” block.  Compare this to  the 1 or 5 IPv4 addresses that you get from your current service  provider, if you even get a globally routeable IPv4 address in the first  place.

So how do you start using IPv6?  Most modern endpoints support  IPv6, from desktops to smartphones; you just need IPv6 connectivity  activated on your LAN for them to srtart communicating.  Typically, any  properly activated IPv6 router will announce the configured IPv6 global  prefix(“subnet”) and router address information once it has its own  connectivity, and the IPV6 nodes will immediately start communicating  once they detect the availability of IPv6.

The best course of action is to use your Internet Service  Provider (ISP), if they can provide IPv6.  For example, users of and get IPv6 natively, as do users of NTT in Japan.   In the United States, Comcast has a beta program (detailed at  whereby any users with a router supporting the “6rd” protocol can get a  “/64” address pool.  Cisco IOS software version IOS 15.1(3)T has 6rd  support, as do modern versions of alternative firmware which run on many  home routers including many popular Linksys models.  Comcast provides  the information needed to configure these services at the aforementioned  site.

Most people will have to use a "tunnel broker" while waiting for  their ISP to offer IPv6.  There are three major providers that offer  free IPv6 tunnel endpoints and address blocks:  Hurricane Electric  (, GogoNet Freenet ( and (  All of these providers use a range of  tunneling technologies and approaches, but they will all offer free  tunnel connectivity and address blocks. Each site has copious details  about how to connect.  Hurricane Electric uses the 6in4 protocol and   provides customized sample configurations IOS.  GogoNet provides a  Windows application that can be downloaded to a PC and can provide  robust connectivity to a single PC or a local subnet, even across NAT  devices.  SiXXS provides a system based on the AICCU and AYIYA protocols  which can do robust auto-configuration and easy NAT traversal.  All  three providers are surrounded by robust communities of enthusiastic  users who are willing to help newcomers!

You may read also about the 6to4 as a possible transition  protocol. While it is simple to setup and supported by a number of  popular home routers, real-world experience has shown that by its nature  it is very fragile, and the use of it as a transition mechanism can be a  source of difficult to troubleshoot issues and lower performance. We  recommend you do not use it and instead get a tunnel with the broker or  and ask your ISP what are their plans to support IPv6.

For more information about what Cisco is doing with IPv6, please visit or ask your questions at

Cisco Employee

"Use the 6to4 protocol on a supported router (" might be probably moved to resite alongside the RFC1149 - due to similar reliability issues (reliance on the unknown third party to feed the carrier of the packets ;-)

Cisco Employee

I agree: 6to4 is a risky proposition.  There are those who are satisfied with the result, but there are much better ways to get IPv6.  I still contend that 6to4 is fundamentally superior to RFC1149.

A good treatise on the case against unmanaged tunnels can be read here:

Cisco Employee
Community Member

I have implemented NAT64 and DNS64 and buld Wireless IPv6 using WLC 4402:

Implementation details and desgin: