Demand-Aware Network Design With Minimal Congestion and Route Lengths

Emerging communication technologies allow to reconfigure the physical network topology at runtime, enabling
demand-aware networks (DANs)
: networks whose topology is optimized toward the workload they serve. However, today, only little is known about the fundamental algorithmic problems underlying the design of such demand-aware networks. This paper presents the first bounded-degree, demand-aware network,
$\textit {cl-DAN} $
, which minimizes
both
congestion and route lengths. The degree bound
$\Delta $
is given as part of the input. The designed network is provably (asymptotically) optimal in each dimension individually: we show that there do not exist any bounded-degree networks providing shorter routes (independently of the load), nor do there exist networks providing lower loads (independently of the route lengths). The main building block of the designed
$\textit {cl-DAN} $
networks are
$\textit {ego-trees}$
: communication sources arrange their communication partners in an optimal tree,
individually
. While the union of these ego-trees forms the basic structure of
$\textit {cl-DANs}$
, further techniques are presented to ensure bounded degrees (for scalability).