  Mobile ad-hoc networks demand routing algorithms able to adapt to network
topologies subject to constant change. Moreover, with the advent of the
Internet-of-Things (IoT), network nodes tend not only to show increased
mobility, but also impose further restrictions to these mobile network systems.
These restrictions include non-functional requirements of low-power
consumption, small-size, and low-cost. ADHOP (Ant-based Dynamic Hop
Optimization Protocol) is a routing algorithm based on ant-colony optimizations
that target such small-size and low-cost platforms, consuming little amounts of
memory and processing power. This paper elaborates on ADHOP to investigate the
use of energy-related heuristics to guide routing decisions. The goal is to
minimize network usage without jeopardizing network operation. We replace the
original ADHOP heuristic of network latency by two energy-related heuristics
based on the battery charge and the estimated node lifetime. Simulations
compare the energy-aware versions of ADHOP to its original version, to AODV and
to AOER. Results show that the proposed approaches are able to balance network
load among nodes, resulting in a lower number of failures due to battery
depletion. The energy-aware versions of ADHOP also deliver more packets than
their counter-parts in the simulated scenario, delivering 2x more packets than
the original ADHOP, and, respectively, 5x and 9x more packets than AOER and
AODV.
