Many of these problems, and others besides, have been troubling Internet gurus for some time. Their solutions have been fed into a new specification for the basic protocols of Internet data transfer, known as IPv6 (version 6) or IPng (next generation). The most significant change in this new standard is the way computers are addressed. Internet addresses are specified using what's called a `dotted quad', four 8-bit numbers (0-255) that uniquely specify each IP-connected computer or device. As the Internet grows, the limited range of these numbers (there's a theoretical maximum of around 4,000 million addresses, though a high proportion unavailable due to the subdivisions into domains) will cause problems when allocating new addresses. As more computers, PDAs and even household devices (yes, you can already buy an Internet-connected refrigerator!) are linked to the net, we'll need many more addresses. So the proposal is to use four sixteen-bit numbers, which will give around 18 million million million addresses (2 to the power 64), which should last a little while at least!