IPv6 is the extended version of IPv4 connectivity and some of the Internet’s most popular web sites such as, Facebook, Google and Yahoo have agreed to participate in the first global-scale trial of IPv6. IPv6 is the long awaited upgrade to the Internet’s main communication protocol known as IPv4. On the World IPv6 Day, participant websites will support native IPv6 traffic on their main web sites on June 8, 2011. Also some of the leading content delivery networks like Akamai and Limelight Networks committed to the IPv6 trial. This trial is being sponsored by Internet society.

Leslie Diagle, the Internet Society’s Chief Internet Technology Officer says ” “It’s an exciting opportunity to take IPv6 for a test flight and try it on for a full 24 hours,” he also mentioned that “Hopefully, we will see positive results from this trial so we will see more IPv6 sooner rather than later.”
It is very necessary to upgrade because Internet is running out of IP addresses using the 30-year-old IPv4 standard. So, they think to motivate using IPv6 now onwards.
As per the statistics, less than 5% of IPv4 addresses are left unallocated to the regional registries. These in turn dole them out to network operators and moreover experts also mention that the free pool of IPv4 addresses will be depleted in a matter of weeks.
The main differences between IPv4 and Ipv6 are as follows. IPv4 uses 32-bit addresses and it can also support 4.3 billion devices connected directly to the internet. IPv6 is better, comparing with IPv4, because it can support a virtually unlimited number of devices directly connected to the internet and uses 128-bit addresses.
World Ipv6 will be very important as it is likely to be a surge of IPv6 traffic across the internet. It is important because only 0.2% of Internet user use IPv6 network according to Arbor Networks. But there are some issues with IPv6 also such as. It is doubtful whether IPv6 will be up to the task of providing efficient performance on such heavy trafficked sites. There may be some sort of slowdowns and a minority of Internet users- 0.05%- will experience slowdowns or may be they have trouble connecting to participating web sites during the trial. It may be because of mis-configured or misbehaving network equipments.
Daigle also mentioned that there may be some individual hiccups for some small access providers or users, but IPv6 is not an experimental technology and also he told he do believe it will work.
Yahoo is also taking this event as a big deal because initially Yahoo was not supporting IPv6. Yahoo said that Participating in World IPv6 Day will allow us to obtain real-life data that we can use to ensure a seamless user experience as we transition to IPv6.