When the internet protocol  IPv4 was developed, mobile phones were not in heavy use and personal computers were not yet commonplace. Now computers, phones, automobiles and even appliances are connected to the web -- and the number of IP addresses that are readily available is dwindling fast.   

IP addresses are unique numbers assigned to all devices that connect to the internet.  The IPv4 provides for an estimated four billion IP addresses. 

There are currently less than five percent left -- about 230 million IP addresses -- and according to the Sydney Morning Herald, experts predict the world will run out within the year.   A video posted on the SMH site features Geoff Huston, Chief Scientist of the Asia Pacific Network Information Center (APNIC) talking about the shrinking supply.  

A countdown depletion site has even been set up to track the fading number of IP addresses, but industry professionals indicate that a crisis can be averted with IPv6. 

"Over the years unless we embark on IPv6 then the internet will get slowly more and more strangled and applications will work in stranger ways," Huston said.

IPv6 would require an upgrade or reconfiguration to certain devices -- and some users might even have to buy new hardware.

Multiple customers may be forced to share IP addresses in the interim -- which may cause IP dependent applications like Gmail, Google Maps and iTunes to stop working.  Black market IP addresses may also begin popping up, Huston warns. 

Richard MacManus of ReadWriteWeb indicates that an explosion of data that is about to take place on the Web -- and is expected to contribute to the rapidly depleting supply of IP addresses -- is due largely to sensor data, smart grids, RFID and other similarly related systems.