After helping to hatch the plan for World IPv6 Day set for Wednesday, a senior network engineer at Facebook is raring to test the site's reworked network

Facebook's Donn Lee has been getting the social network ready for this first worldwide test flight of IPv6 since last fall when plans for the June 8 event were put in place. Wednesday is the day that the giants of the Internet - Google, Yahoo, Microsoft, Verizon and Facebook - will give IPv6 a whirl and see how it works.

Lee, who came up with the idea for World IPv6 Day with Google network engineer Lorenzo Colitti, said he's confident all will go well and he's not expecting any surprises.

"I'm completely excited," Lee told Computerworld. "It's grown into a life of its own from our initial idea that we had in the hallways of a conference last summer. Seeing all the excitement and energy around this day is immensely rewarding. This is when the Internet enters into the next stage of its expansion."

IPv4 is the Internet's main communications protocol, but it is quickly running out of unique IP addresses for all the computers, smartphones and other devices that need to be hooked up to the Internet. Hence, the development of an upgrade -- IPv6, which is said to provide more than 4 billion times more addresses than IPv4.

Some people worry that migrating to IPv6 will be time consuming and expensive. World IPv6 Day is designed to test IPv6 and see how well it works. Internet users on Wednesday can think of themselves as test pilots.

Participating companies will flip the switch at 8 p.m. EDT Tuesday.

"This is going to be like opening night," Lee said. "It's a 24-hour test. We'll turn it off after 24 hours. Most participants will... We think we've covered all our bases."

He added that the participants have been going through "dress rehearsals" and he's confident that most Facebook users won't see any difference in the site's performance Wednesday.

"We've already done some very comprehensive tests and simulations here and we have not had any effects to Facebook users," Lee said. "We've tested users to see what their IPv6 and IPV4 connectivity is. We've been collecting data for many months. We pretty sure that our data is sound."

Lee, who previously worked at Google and Cisco Systems, said a handful of Facebook engineers have been working on updating the company's network so they can run a dual stack, which means running both IPv4 and IPv6 at the same time.

The site will check a user's system and if it supports IPv6, it will use IPv6 for the first time. Most people don't have IPv6 and will fall back to IPV4.