A multimedia connection in a wireless network typically utilizes three
important network resources: wireless link resources, wired link
resources and network server resources. When the users participating
in the connection are mobile, these resources must be reallocated as
the users move in a manner so that the connection is not disrupted.
This dissertation contributes a set of algorithms for supporting
connection mobility through efficient and, in certain cases, optimal
use of these network resources.
In the first part of this thesis, we examine various techniques for
allocating wireless channel resources to connections. We define three
important practical problems in channel allocation faced by network
engineers. We then derive new and optimal admission control
policies for each of these problems. We further show that the optimal
policies provide significant performance gains over other previously
proposed policies. We also develop computationally-efficient
algorithms for deploying these optimal policies in real-time at the
In the second part of this thesis, we examine ways of rerouting the
connections of mobile users so that the wired link resources are
utilized efficiently. We propose, implement, and experimentally and
analytically evaluate the performance of several connection rerouting
schemes. Our study shows that one of our schemes is particularly well
suited for performing connection rerouting. This scheme operates in
two phases: a real-time phase where a reroute operation is
executed without causing any disruption to user traffic, and a
non-real-time phase where more efficient reroutes are effected.
In the third and final part of this thesis, we examine ways of
efficiently utilizing the computational resources in the network. We
study policies for migrating user agents, which act as proxies for
mobile users, as users move. We show that two simple threshold
policies that we propose, a Count policy which limits the number of
agents in each server and a Distance policy which gives preference to
migration of agents that are farther away from their users, deliver
excellent performance across a wide range of system parameters and
configurations.
Opens in a new tab
