Concentric Sky, Inc.

Not surprisingly, there are several ways to answer this question. One way to think of the size of the Internet is to count its users. China recently announced that they have reached 298 million users - a number just shy of the entire population of the United States. Using this same methodology to count all Internet users, we can estimate that there are about 1.6 billion Internet users - or put another way, about 24% of the world’s population.

Another way to look at the question is to count the number of unique pages on the Internet. Microsoft’s new Bing search engine, for example, counts over one trillion web pages - that’s 1,000,000,000,000 unique URL’s - which would require the average person six hundred thousand decades to read. Not a small endeavor.

Google, on the other hand, reached the 1 trillion benchmark about 12 months ago. Compare this to 1998, when Google had indexed a mere 26 million pages. So, relative to today’s total world population, there are about 150 web pages per person. Of course, many web pages contain the same or similar content making this measurement technique less than ideal.

Yet another way to scope the Internet is to count the number of accessible domains. Domain Tools counts domain registrations and shows a total of about 110 million active domains, including all .com, .net and .org TLDs. The Internet Systems Consortium uses a slightly more accurate measurement - the total number of allocated IP addresses which serve up domain names. The most recent ISC Domain Survey shows a total of about 700 million domains, as illustrated in the chart below.

But even this method has its flaws. While the total number of IP addresses is technically limited to about 4.29 billion, several techniques ( such as NAT ) are used to expand this number in ways that are hard to track. Though useful, it can be hard to put the ISC’s numbers into perspective.

Other measurements exist, but are equally hard to pin down - for instance, the total amount of data accessible via the Internet, or the total amount of Internet traffic.

So, the short answer to our opening question is - it depends on how you look at it.

One thing we do know for sure is that the Internet is getting bigger. Mobile traffic alone is expected to soon reach levels that test the current Internet infrastructure, while simple web traffic is projected to expand 50-fold by 2015. Initiatives such as IPv6 and Cisco’s Smart Grid seek to keep up with - and even accelerate - this growth.

The rise of cloud computing is another major contributor to the Internet’s rapid growth, with thousands of new virtual machines coming online daily. Growth projections are quite positive for cloud computing in 2009. Even the US Government has jumped on the bandwagon, recently announcing plans to offer cloud computing services of its own.

While we can’t give a single measure for the size of the Internet, its growth is easier to model. Several models have been proposed for this over the years, including neural networks and genetic algorithms. Interestingly, a group of researchers recently predicted that the growth of the Internet conforms to Moore’s Law and will double every 5.32 years. We’ll know if this model is accurate in just a few short years.

No matter which measurements or models are used, the growth of the Internet will present numerous opportunities for business. A 2008 survey by the Pew Internet Project offers some exciting predictions, some of which are already materializing.

One prediction in particular that we have our eye on is the growth of the mobile space. We see a number of fascinating intersections between the growing mobile space and Social Media - not to mention emerging technologies such as Google Wave.

As we watch all of this unfold, we’ll be working closely with our clients to take maximum advantage of these intersections - and to get the most leverage possible from the new directions in which the Internet will take us all.