I. INTRODUCTION
Currently, the internet is widely used and much networked
equipment such as set top boxes and PCs utilize 24/7
networking services. For example, remote management such as
automatic firmware update and content download can be
performed without the user’s attention. However, this
equipment constantly consumes electric power, with most of
the energy consumption occurring when no one is present and
the equipment is in an idle state, continuously receiving
network service [1]. The technique of adding a subsystem to
provide proxying for a host system to continue network service
has been studied (Figure 1). By introducing proxying, for
example, maintaining its presence on a network, it is possible
to reduce power consumption, even though the system is in a
sleep state. The goal of proxying is to enable full network
connectivity even while the host system is asleep, while hiding
this from the rest of the network [2]. The power state transition
of the host system also causes a state transition between the
host system and the subsystem. Just before the host system is
about enter a sleep state, the network configuration of the host
system is copied to the subsystem; then, the network control
switches to the subsystem. After that, the subsystem behaves as
the host system and provides network services. When the host
reverts to an active state, it resumes control of the network and
services once again [5]