In less than 18 months there will be no more big blocks of net addresses to give out, estimates suggest.
Predictions name 9 September 2011 as the date on which the last of those tranches is released for net firms and others to use.
Everything connected to the net needs an "IP address" to ensure data reaches the right person or device.
Experts say that the net's entire existing address space will be exhausted about a year after that date.
A newer scheme is being rolled out but many firms and countries are being slow to switch, experts warn.
So, if CH ready for IPv6?!