Addressing on the Internet
IPv4 allows a theoretical maximum of 4.3 billion addresses
- In practise, due to overhead & addresses needed for infrastructure, one can only use about 1/4 to 1/8: 0.5 - 1.1 billion addressable nodes [other research suggests that it will be hard to use more than 240 million addresses: rfc3194, hd ratio > 0.87]