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Priority Based Energy Efficient Access
Networks
A thesis submitted in fulfilment of
the requirements for the degree of
Master of Engineering
Rakesh Kumar Pradhan
B.Tech.
ELECTRICAL AND COMPUTER ENGINEERING
COLLEGE OF SCIENCE, ENGINEERING AND HEALTH
RMIT UNIVERSITY
JANUARY 2013
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Abstract
Information and Communication Technologies (ICT) enjoys a reputation as a
green technology by reducing the cost of information and service delivery and
promoting such activities as teleworking, online conferences and training which
reduce the need for workers to utilise air and road transport. The massive growth of
the internet and the ubiquitous nature of internet enabled devices have raised the level
of concern about the ICT sector energy consumption.
Utilisation of the transmission links between network devices is a focus for
energy conservation. Improving link utilisation and reducing energy use during idle
periods are topics for current research. Reducing the energy required to operate
network devices such as switches, routers and concentrators is a key goal in the quest
to make the network more energy efficient. Power management mechanisms that
control and manage traffic flows and link operating states can lead to energy efficient
network device and link operations and thereby improve the overall energy efficiency
of the worldwide digital network. The trade-off between power management and
performance is an important aspect of this research and an investigation has been
carried out to identify energy savings that have a minimal effect on performance. A
focus on identifying Quality of Service requirements for traffic streams in a
differentiated service environment provides an approach that has led to a traffic
priority transmission process that conserves energy.
The power management mechanisms introduced in this thesis propose traffic
management based on traffic class, the link states being managed based on buffer
utilisation and links being put into low power modes. By utilizing link interfaces
(intermediary buffers) to facilitate device component burst operation (including the
device link processor, storage and other links component) it was found that
performance was improved whilst reducing power utilization.
This thesis addresses energy consumption in Ethernet Access Networks,
investigates and validates existing models and proposes a novel method to improve the
energy efficient operation of Ethernet links that incorporates prioritized traffic
management.
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Declaration
I certify that except where due acknowledgement has been made, the work is that of
the author alone; the work has not been submitted previously, in whole or in part, to
qualify for any other academic award; the content of the thesis is the result of work
which has been carried out since the official commencement date of the approved
research program; and, any editorial work, paid or unpaid, carried out by a third party
is acknowledged.
Signature: _________________________
Rakesh Kumar Pradhan
Date: 31/01/2013
