Mobile computers use wireless channels to communicate with other computers. Efficient
channel allocation is at the heart of an efficient mobile computing system. The
finite number of channels should be efficiently allocated to maximize throughput and
to avoid co-channel interference. Temporal variations in channel demand (load) require
channel allocation to adapt dynamically to the changing demand. The presence
of load imbalance does not automatically imply the usefulness of channel transfer. In
this paper we present a probabilistic analysis of the temporal imbalance in channel
demand. The effectiveness of channel transfer depends on the duration for which the
imbalance persists. This duration is influenced in part by the velocity of mobile units.
The wide variance in velocities of the mobile units can be handled by using a hierarchical
cellular layout. Bulk channel transfers can be employed to reduce the overheads
of channel transfer and to enable the system to quickly adjust to spatial variations
in channel demand. The results of our analysis provide guidelines for the design of
dynamic distributed channel allocation strategies.