Today the well of addresses on the Internet officially runs dry, but there's no need to panic. New addresses, which are designed not to run out for a long time, are already in operation.

Today the well of addresses on the Internet officially runs dry, but there's no need to panic. The exhaustion for years, and new addresses—which are designed not to run out for a long, long time—are already in operation.

The Number Resource Organization (NRO), an industry group made up of five regional Internet provider registries, held an event in Montevideo, Uruguay, today where members announced that it had today handed out the last of the available addresses on the old system.

"This is truly a major turning point in the on-going development of the Internet," said Rod Beckstrom, President and CEO of ICANN (Internet Corporation for Assigned Names and Numbers), the organization responsible for assigning IP addresses. "Nobody was caught off guard by this, the Internet technical community has been planning for... depletion for quite some time."

Two years ago the organization proposed that when the pool of unused addresses had been depleted to five "blocks," as , each registry would get one of the blocks. The agreement was ratified by ICANN, and those blocks were assigned today. Each block comprises 16.8 million addresses, according to NRO.

The old system, called IPv4, uses a system of numbers, typically separated by decimals, that even casual users of the Internet would probably recognize (if your unsure, check your computer or phone's network settings for numbers like "192.162.2.235"). IPv4 had about 4.3 billion addresses, which ran out more rapidly once mobile devices with Internet connections became commonplace.

Now all new Internet addresses will use IPv6, a system that has more numbers and characters, and is said to have enough spots for 340 trillion, trillion, trillion unique IP addresses. Equipment that uses IPv6 has been in use since 1999.

The two systems aren't automatically compatible with each other, however, so service providers and network operators need to upgrade systems to ensure the transition is smooth, which is why there has been so much recent attention focused on the subject.

"This is an historic day in the history of the Internet, and one we have been anticipating for quite some time," NRO Chairman Raúl Echeberría said. "The future of the Internet is in IPv6. All Internet stakeholders must now take definitive action to deploy IPv6."

Despite the magnitude of the issue, most users should not even notice the change from IPv4 to IPv6, the experts said. If you own a business with an online presence or host your own Internet services, you should check out .

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