Today, the internet celebrates another impressive milestone in its growth with the official large-scale debut of the internet protocol standard known as IPv6.

Back in February, the well dried up for the previous standard, IPv4. With this standard, there was a theoretical maximum of 4,294,967,296 IP addresses, which equates to 4.2 billion. All 4.2 billion addresses were allocated and tt was then, the Internet Corporation for Assigned Names and Numbers (ICANN) announced the future of the internet expansion would rely on IPv6.

 No one was caught off guard by this. The Internet technical community has been planning for IPv4 depletion for some time. But it means the adoption of IPv6 is now of paramount importance, since it will allow the Internet to continue its amazing growth and foster the global innovation we've all come to expect, Rod Beckstrom, ICANN's president and chief executive, said at the press conference.

Today is the day IPv6 was put into effect across the world and tested out for the first time. Companies across the world, including tech giants Facebook , Google and Verizon, have prepared for this day for a while. Google says the day, which is really just a 24-hour test period, is imperative for the evolution of the internet.

This is a crucial phase in the transition, because while IPv6 is widely deployed in many networks, it's never been used at such a large scale before. We hope that by working together with a common focus, we can help the industry prepare for the new protocol, find and resolve any unexpected issues, and pave the way for global deployment, Lorenzo Colitti, Google's network engineer, said in a blog.

Verizon is another major tech company participating in IPv6 day. All told, there are approximately 400 companies participating.

World IPv6 Day marks an important industry milestone with the first global-scale trial of IPv6, Jean McManus, executive director of Verizon's Corporate Technology organization, said in a statement. Verizon was an early promoter and adopter of IPv6 back in the mid-1990s. It is very positive to see interest in IPv6 continuing to grow, and World IPv6 Day has just added to the IPv6 momentum.

Verizon said during the 24-hour test period, users with IPv6 connectivity to the Internet will be able to connect to two IPv6-enabled Verizon websites: and Verizon has enabled technical support for this endeavour. Level 3 has helped out with the transition to IPv6 in differing ways such as its dual-stack IPv4/IPv6 architecture.

Level 3's dual-stack approach is meant to be a bridge that will simplify the protocol migration process for our customers and the industry as a whole, Andrew Crouch, president of sales for Level 3, said in a statement. Backed by a wealth of experience in defining and developing the protocol, Level 3 is committed to offering its customers a secure, reliable and efficient means of transitioning to IPv6 to ensure they receive the same high-quality service they have come to expect from Level 3.

It's important to note, most consumers are still using IPv4. However, for those using IPv6 enabled browsers, various reports from the media indicate connectivity has not had any issues. Also, traffic on IPv6 enabled browsers is reportedly up 30-60 percent.

The major difference between the two is IPv4 relies on 32 bit addresses, which is expressed in four octets. An example of IPv4 is 192.168.10. IPv6 uses 128 bit addresses expressed in hexadecimal numbers, for example 2001:0db8:85a3:0000:0000:8a2e:0370:7334. ICANN estimates its one hundred trillion times bigger than IPv4, which makes it virtually inexhaustible for the foreseeable future.

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