  The process of Vertical handoff has become one of the major components of
today's wireless environment due to the availability of the vast variety of
signals. The decision for a handoff should be performed catering to the needs
of the current transmission that is being carried out. Our paper describes a
modified Ant Colony Optimization based handoff mechanism, that considers
multiple criteria in its decision making process rather than a single parameter
(pheromone intensity). In general, ACO considers the pheromone intensity and
the evaporation rates as the parameters for selecting a route. In this paper,
we describe a mechanism that determines the evaporation rates of each path
connected to the source using various criteria, which in turn reflects on the
pheromone levels present in the path and hence the probability of selecting
that route. Experiments show that our process exhibits better convergence
rates, hence better usability.
