Steiner's Problem concerns finding a shortest interconnecting network
for a finite set of points in a metric space. A solution must be a tree,
which is called a Steiner Minimal Tree (SMT), and may contain vertices
different from the points which are to be connected. Steiner's Problem
is one of the most famous combinatorial-geometrical problems, but
unfortunately it is very difficult in terms of combinatorial structure
as well as computational complexity. However, if only a Minimum Spanning
Tree (MST) without additional vertices in the interconnecting network is
sought, then it is simple to solve. So it is of interest to know what
the error is if an MST is constructed instead of an SMT. The worst case
for this ratio running over all finite sets is called the Steiner ratio
of the space.
The book concentrates on investigating the Steiner ratio. The goal is to
determine, or at least estimate, the Steiner ratio for many different
metric spaces. The author shows that the description of the Steiner
ratio contains many questions from geometry, optimization, and graph
theory.
Audience: Researchers in network design, applied optimization, and
design of algorithms