Wednesday is World IPv6 Launch Day, a time when ISPs, major websites and network engineers will permanently flip the switch over a different form of addressing system. For the most part, the IPv6 transition will go unnoticed and few will care about what is an arcane and important element of Internet architecture. But here’s where things may go wrong as IPv4 lingers.
At its heart the IPv6 addressing issue is exactly that… a big change to a new type of address. Every device that is hooked up to a network, be it your iPad or a Facebook server, has an IP address so routers know where to send the packets that make up your Facebook (s fb) profile or your Netflix (s nflx) stream. Sadly, back in 1980s when the lords of the net were thinking up an address scheme, they used IPv4, which only allows for a 32-bit address and about 4.2 billion total IP addresses.
But darned if the growth of the web (all those servers!) and the growth of consumer devices (all those smartphones!) hasn’t caused the 32-bit addresses to run out. So since about 2007 people started pushing ISPs and websites to switch over to IPv6, which allows for 128-bit numbering system (or a total of 340,282,366,920,938,463,463,374,607,431,768,211,456 possible addresses). But because of a variety of workarounds put in place by ISPs and the general lack of hellfire and damnation to ensure ISPs and web companies make the change or risk getting cut off from the Internet, the transition to IPv6 is happening slowly.
And for the most part that isn’t a problem. But, as we consume more apps that take advantage of several ports (think of a port as a door that allows certain types of traffic through), and more people in our homes use those apps, consumers may feel a bit inconvenienced. This is a result of the workarounds that ISPs have in place to forestall their transition to IPv6 and ensure that customers can still access sites that haven’t already transitioned. But here’s how the delay in shifting to IPv6 and the reliance on a workaround could affect you, as a consumer according to a report from the Broadband Internet Technical Advisory Group. Bitag is a group of communications engineers and researchers created to help promote good Internet policy.
Trouble with iTunes or Google Maps: Certain apps such as Google Maps (s goog) or iTunes (s aapl) use more than one port to communicate back to the service and because users would be sharing one or just a few IP addresses, those ports may not be available. From the report issued in March by Bitag:
For example, some applications, such as Apple iTunes and Google Maps make use of multiple ports for a single transaction. A single user running a single instance of an application on one personal computer may encounter no issues, while a family of four using multiple Internet connected devices concurrently could experience a situation where an open port is unavailable. Applications with no ports available for communication would not function as expected.
Security: When users share one IP address, the ISP generally creates an abstraction layer to determine where the packets need to go to in the home. But this abstraction layer becomes a security risk. By attacking one IP address, a hacker could take down or infect all Internet-connected devices in a home. It becomes a single point of failure.
Court orders and DMCA takedowns: Shared IP addresses can make it hard for an ISP to determine who is actually downloading copyright materials. This actually may not upset end users or the ISPs as long as no one gets dragged into court as part of a hunt for settlement dollars.
Pixellated YouTube videos: The workarounds associated with either sharing a single IP address among a block of users or even a block of homes is just one option. Another is running both networks simultaneously and translating traffic between them. This adds some computational overhead and latency that in CableLab tests caused there to be delays in streaming and receiving HTTP video packets.
Stories about IPv6: As long as networks linger in the land of IPv4 every June, it’s possible you will have to see headlines talking about the need to get everyone to transition to IPv6. Hopefully, ISPs and major web sites are getting on the ball.
Tomorrow’s IPv6 Day involves more than a dozen companies who have committed to permanently enable IPv6 (last year many of the providers turned it on but then turned it back off in an effort to understand what would happen when they switched). I’m personally encouraged that Time Warner Cable, my ISP, is finally announcing its plans to transition. Other major networks that have transitioned or are in the midst of doing so are Verizon, Comcast and KDDI.