  In this paper, an energy efficient passive optical network (PON) architecture
is proposed for backhaul connectivity in indoor visible light communication
(VLC) systems. The proposed network is used to support a fog computing
architecture allowing users with processing demands to access dedicated fog
nodes and idle processing resources in other user devices within a building.
The fog resources within a building complement fog nodes at higher layers of
the access and metro networks and the central cloud data center. A mixed
integer linear programming (MILP) model is developed to minimize the total
power consumption associated with serving demands over the proposed
architecture. The results show that the PON backhaul network improves the
energy efficiency of fog computing by 66% for networking and 12% for processing
compared to an architecture based on state-of-the-art Spine-and-Leaf
connectivity.

Networking and Internet Architecture