The arrival of World IPv6 Day has prompted concerns about how the switchover will affect internet security, accessibility and performance.
The event, organised by The Internet Society, marks the official start of IPv6 support by ISPs, router manufacturers and websites across the globe, including Yahoo, Facebook, Google and YouTube.
The change from IPv4 to IPv6 presents many challenges that organisations need to be aware of and solve.
According to findings proffered by the Society, there are no IPv4 addresses left in the Asia Pacific region and Europe is expected to run out later this year, which is why the move to IPv6 is so important.
"The support of IPv6 from these thousands of organisations delivers a critical message to the world: IPv6 is not just a nice to have'. It is ready for businesses today and will soon be a must have'," said Leslie Daigle, chief internet technology officer at the Internet Society.
"We believe the commitment of these companies to deploy IPv6 will ensure that they remain industry leaders [and] any company wishing to be effective in the new internet should do the same."
However, IT industry watchers have warned that the switch from IPv4 to IPv6 could create security headaches and user experience problems for many firms.
Michael Allen, application performance management director at network monitoring software vendor Compuware, said the switchover will affect the way internet browsers and devices connect to the internet, which could cause accessibility issues for some users.
"The change from IPv4 to IPv6 certainly brings more addresses, scalability and flexibility to the internet, but at the same time it presents many challenges that organisations need to be aware of and solve," said Allen.
"This not only puts end user experience at risk, but also impacts business revenue and brand reputation, as poor application performances will not be well received."
This situation will be exacerbated by the fact that very few networks are IPv6-ready, warned Allen.
"Most carriers do not provide full end-to-end IPv6 connectivity. This means that some IPv6 traffic will have to be tunneled' through IPv4, [which will also lead to] poor performance and availability issues," he added.
