Traceroute Statistics
Summary Description
What is Measured
For the TTM project, we determine the path between two Test Boxes with
the Traceroute program. The output of this program shows how data
travelled between 2 specific boxes at the time the program was run.
The collection of all traceroutes done around a particular moment in
time can be used to describe the connectivity of the Internet as a whole.
The Internet can be seen as a sparsely connected collection of nodes, where
each node is one IP address (and thus, one interface on a router).
Sparsely means that it is possible to travel from each node to each other
node, but that one may have to travel through intermediate nodes. The
properties of this graph are described by the average and variance of the
number of nodes that one has to pass to travel from any one node to
another: the lower the average, the better the Internet is connected. A
lower variance suggest that connectivity to all sites passes the
same number of hops, and thus that delays will be more predictable.
By assigning the IP addresses of the traceroute to an AS number, one
can see how many AS's were traversed between 2 boxes. As was the case at
the AS level, the graph again shows how well the Internet is connected.
By comparing graphs for an individual site, one can get an impression
whether one's side has a better (or worse) connectivity to the global
Internet. One has to be a bit careful here. The distribution also depends
on the global distribution of the Test Boxes, and sites in areas with only
a few boxes (Asia, South America) will always appear to be worsely connected
than sites in areas with a high number of boxes (Europe, North America).
Why it is Measured
These graphs a by-product of the TTM measurements that have
global interest.
What You Can Do with It
Data is by Test Box and for the entire sample.
By comparing the shape of graph for an individual Test Box against the
global distribution, one can get an impression of how well one's site is
connected to the Internet. In general, a lower average and a lower spread
are better.
Data over time
One can also look at the data over time, sharp jumps indicate
that upstreams were added (or lost) and better (worse) routing was
possible.
Plans
This is a first step towards an analysis of the development of
the routing graph over time. We are currently working our way backwards
through older data, when that is done, we will revisit this analysis.
Watch this page for further results.
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