Mapping the growth of the Internet

The Internet is growing rapidly, causing concerns that the address space for IPv4 may soon be used up. Taking a snapshot of the Internet size can help in planning the future evolution and capabilities of the Internet as well as planning the implementation of the next generation IPv6. We extended our previous work on measuring the number of publicly accessible web servers to make more accurate measurements of the size of the Internet. An improved importance sampling approach is introduced which achieves a significant gain over Monte Carlo methods. The growth of the Internet is mapped by periodic measurements of the number of active web servers.