In [28] we show maps of the information flow on subsystems of the
global Internet with a strong concentration within the US. The main increase in the
information flow rate has been observed in the past few years. In Fig. 6
we plot the NSFNET backbone traffic (see Fig. 4 in [28]) normalized by the
number of Internet hosts for each of the information services WWW, Gopher, and WAIS
.
Fig.6:
NSFNET Backbone Traffic normalized by the Number of Internet hosts for each Service:
WWW, Gopher, WAIS
The data are plotted on a logarithmic scale for the time since end of 1992.
We can observe that the hyper-media based WWW is growing at a rate of about 37% per
month up to the first quarter of 1993. At that time an advanced user interface to
WWW was introduced, NCSA's Mosaic [44].
Since it is available for most of the common
computer operating systems, it misses some of the advanced drag-and-drop features
that we had available 1991 for the NeXTstep based Diagram interface. At the same time
it created a very common, easy to use environment which appears to have triggered
a sharp transition to a higher information flow rate which still continues to grow
at 25% per month (status: May 1994) . During the transition period the temporary growth
rates exceeded 600% per month [38].
In the context of non-equilibrium phase transitions we would identify the number of Internet hosts as control parameter and the traffic per Internet host as order parameter (see [12]). The analog of the free energy or generalized potential would be an information deficit that induces the generation of different unstable modes (in the sense of positive growth rates) of information flow or transport services (WWW,Gopher, WAIS).
The interpretation of fig. 6 could then be that there is a phase transition between two levels of information flow both of which have about the same stable growth rates with respect to the growth of the number of Internet hosts. The rapid transitions between those levels is induced by the release of X-Mosaic. The over-shooting during the summer could either indicate a novelty/exploratory effect or it could be a seasonal effect, which could be tested during the following summers.
Due to the highly connected nature of the Internet, information can propagate very
rapidly through avalanche effects: Once a hyper-media-document has been released and
made known to an active group of users, a link to it will be included in the local
hyper-media-document of that user and consequently the news about the original document
can spread rapidly like a global rumor. There are also key archive sites that are
frequented by many users and thus has a dramatic effect on the visibility of specific
documents. For example the document in [37] had an increase in access-frequency
by more than 100% after it was announced in the NCSA ``What's New?'' page