Carlos M. Martinez-Cagnazzo

Chris Grundemann's blog (it's a post from 2009 but I just found it) has interesting take on how to manage IPv6 space and how current allocation strategies could lead to another run-out scenario just like the one we all saw happening yesterday with IANA's IPv4 pool running out.

One of my first projects at LACNIC is to define a set of IPv6 adoption metrics. There are at least three different possible points of view here. One could look at this from the point of view of criticial infrastructure (routers, DNS servers), services (web sites, mail servers) or the end users.

Together with my friend Roque Gagliano from LACNIC, we presented a short talk on using IPv6 via 6to4 at home. Two different approaches were shown: Roque flashed his home router with an open source firmware called DD-WRT while I used a local Linux box as a local IPv6 router effectively creating two distinct network topologies for v4 and v6 at home.

Here are the slides for this talk.

Yesterday I was in need of detecting when a web site or page is accessed via either IPv6 or IPv4. I wrote two rather simplistic PHP functions that so far seem to be up to the job. They just look for an ocurrence of the symbol ":" in the "REMOTE_ADDR" server variable. Here they are:

6to4 is one of the many transition mechanisms proposed by the IETF to ease the move towards an IPv6 internet. It is a tunneling protocol which encapsulates IPv6 packets in the payload of an IPv4 packet, with the added feature that the remote endpoint (the 6to4 Relay) of the tunnel configures itself automatically and uses a well-known anycast IPv4 address.

6to4 es uno de los varios mecanismos de transicion de IPv4 a IPv6 que han sido propuestos por el IETF. Es un mecanismo de tunelizacion de IPv6 en un payload IPv4 con la caracteristica adicional de que el extremo remoto del tunel puede congurarse automaticamente ya que usa una direccion well-known como extremo remoto. Es facil de congurar y tiene buena performance. Sin embargo, presenta algunos desafíos a la hora de poderlo utilizar de manera estable detras de un NAT con IP publica variable, como es el caso de la inmensa mayoria de servicios ADSL hogarenos.