Computing system designs of today take on either the interactive or the proactive
form. Motivated by the user’s desire to make his/her computing experience more
intelligent and personalised, the progression from interactive (human-centred) to
proactive (human-supervised) is evident. It can be observed that current research
mainly emphasises the user as the dominant focus of a user-system interaction.
Consider a model that we called the opponent-process model. It contains two
processes, one representing the user and the other the system, where both processes
are capable of dominating each other, though working collaboratively towards a
predefined task. We argue the necessity to design computing systems which are
balanced in this model, such that the system process, at times, becomes the dominant
process. We refer to this as the pro-collaborative design form.
We dissect mobility into the notion of a nomadic user and the notion of a
nomadic system. The examination into the nomadic user problem space reveals the
potential for applying the pro-collaborative approach in optimising handoff
management. Significant performance advantages can be obtained with our proposed
S-MIP framework, based on the pro-collaborative design, when compared with
established handoff latency optimisation schemes. The key differentiator lies in its
indicative approach in addressing handoff ambiguity. Instead of passively
anticipating through prediction as to when a mobile user might cross network
boundaries (user-dominant), the system actively indicates to the user when, where
and how to handoff (system-dominant). This eliminates the handoff ambiguity.
Regarding the notion of a nomadic system, that is, the ability to move services
offered by computing systems to arbitrary points in the Internet, we explore the idea
of the dynamic extension of network services to a mobile user on-demand. Based on
the pro-collaborative form, we develop the METAMORPHOSE architecture which
facilitates such a dynamic service extension. By assuming the proliferation of
programmable network switches and computational resources within the Internet, we
re-examine how ‘loose’ service agreements between network services providers can
be, to achieve such borderless moving-service offerings.
The viability of the pro-collaborative form is reflected through our design and
implementation of protocols and architectures which address the notion of nomadic
user and nomadic system