Figures are regularly quoted as to how many people there are on the internet, ranging from 30 million to around 100 million and we hate to play the doomsayer, but they are all pretty meaningless, because it is impossible to know. The nearest set of figures, in our opinion, relates to the minimum number of hosts there are on the net, and by hosts we mean every computer that has an IP address associated with it. However, it should be noted that these days a host may not mean a single machine on the net. Due to virtual hosting, a single machine can act like multiple machines, and have multiple domain names and IP addresses. The most accurate and generally trusted survey comes from Menlo Park internet software and service provider Network Wizards Inc, whose owner/operator Mark Lottor has been compiling a bi-annual survey since 1987. This survey too has its self-confessed flaws, but it will have to do for now. His latest survey, just released shows 29.67 million hosts on the internet as of January, compares to an adjusted figure of 26.05 million six months earlier, representing a 13.9% rise in that period. The reason for the adjustment is that this time Lottor has changed the survey method. Up to and including the last survey, in July 1997, he calculated the number of domain names that have an IP address associated with them – the reverse of the new method. The new system queries the domain name system for a name associated with every possible IP address. Rather than searching the 4.3 billion possible IP address, it restricts itself to those that have been allocated by the Internet Assigned Numbers Authority (IANA) to ISPs and corporations – for instance ComputerWire has been allocated 256 IP addresses each for its US and UK operations respectively. However, Lottor notes that the new survey has problems in common with the old method, in particular that just because a hostname is assigned an IP address, or the other way round, it does not necessarily mean that the host actually exists. In an attempt to ascertain how many of them actually existed, Lottor did a ping operation on one percent of the sample of all the hosts found and extrapolated from that how many of the hosts were real and turned on. This resulted in just 5.33 million replies to the ping, out of the 29.67 million. But of course, if a corporation was pinged outside office hours many of its PCs, for instance, would be turned off and there for would not reply to pings. And bearing in mind world time zones that could be quite a problem. Plus the fact that many, such as ComputerWire have not used up all their allotted IP addresses yet. Lottor’s notes conclude with it is not possible to determine the exact size of the internet, where hosts are located, or how many users there are. Quite.
