Address:
Chestnut street 3600, MB 752
Philadelphia, PA, 19104
USA
=========================================================================== E-mail:
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Current Ph.D. Study:
lComputer and Information Science,
University of Pennsylvania August
2007 - Now
Advisor: Boon Thau Loo Previous B.E. Study:
lComputer Science and Technology,
Tsinghua University
August 2003 - July 2007
=========================================================================== Research
Interest:
lNetworked system;
lMobile Ad-hoc Network;
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Paper Abstracts:
lTitle:A Declarative
Perspective on Adaptive MANET Routing Author: Changbin Liu,
Yun Mao, Mihai Oprea,
Prithwish Basu,
Boon Thau Loo
Abstract: In this paper, we present a declarative perspective on adaptable
extensible MANET protocols. Our work builds upon declarative networking, a
recent innovation for building extensible network architectures using
declarative languages. We make the following contributions. First, we
demonstrate that traditional MANET protocols, ranging from proactive, reactive,
to epidemic can be expressed in a compact fashion as declarative networks, and
we validate experimentally the use of declarative techniques to implement
traditional MANETs emulated on a testbed cluster. Second, we show that the
declarative framework enables policy-driven adaptation,
in which a generic set of declarative rule-based policies are used to make
runtime decisions on the choice of MANET protocols. Third, we present some
initial ideas on fine-grained protocol composition and adaptation, where a
typicalMANET protocol can be composed and adapted from simpler components.
lTitle:Network Utility Maximization for Triple-play Services Author: Lei Shi,
Changbin Liu, Bin Liu,
Tsinghua University
Abstract: It is
well-known that Next-Generation Network (NGN) will inevitably carry triple-play
services (i.e. voice, video and data) simultaneously. However, the traditional
strict-priority based scheduling algorithm intensively used in current Internet
can not maximize the overall network utility for NGN, instead brings significant
global welfare loss. In this paper, we study how to achieve Network Utility
Maximization (NUM) in NGN running triple-play services. By investigating the
characteristics of most of its traffic classes, we explicitly present their
utilities as the function of allocated bandwidth. We further formulate the NUM
objective as a nonlinear programming problem with both inequality and equality
constraints. A solution using Lagrange Multiplier is given on the simplified
problem with only equality constraints, which indicates the major distinction
from strict-priority based scheduling, the existence of a turning point for IPTV
users. Simulations are also carried out using LINGO on the original complicated
problem. Several useful results are presented on the new features of the
NUM-based scheduling. We also discuss the methods to alleviate the impact of
turning point and the consequent unstable bandwidth allocation.
lTitle:Max-min
Utility Fairness in Link Aggregated Systems Author: Satya R. Mohanty,
Changbin Liu, Bin Liu and
Laxmi N. Bhuyan
Abstract: We consider utility max-min fairness of application traffic of a Next
Generation Internet (NGI) service model contending for network bandwidth. The
physical infrastructure that offers the bandwidth is a link-aggregated system
where the links can be homogeneous or heterogeneous. Traffic can broadly be
categorized into a few distinct classes and the containing flows in each class
utilize the available bandwidth in the same way. The basis of this
categorization is the realization that different applications derive different
utility even when alloted the same bandwidth. The goal is to allocate bandwidth
so as to equalize the utilities to each class is in a maximal and fair way. Once
the required rates are computed these are utilized by the scheduler for
scheduling packets over the links.
lTitle:Utility-based Bandwidth Allocation for Triple-play Services Author: Changbin Liu,
Lei Shi,
Bin Liu,
Tsinghua University
Abstract: It is expected that, in the near future, the Public Switched Telephone
network (PSTN), the cable Television network and the IP network will converge
into the Next-Generation Network (NGN). A pragmatic challenge in facilitating
the NGN is how to schedule traffic and allocate bandwidth among the triple-play
services. Different from the traditional strict-priority based scheduling
intensively used in NGN industry, in this paper, we investigate this issue in
the objective of Network Utility Maximization (NUM). By excavating the
characteristics of the most traffic classes running in NGN, we explicitly
present their utilities as the function of occupied bandwidth. Furthermore, a
novel scheduling scheme based on NUM is derived using Lagrange method with KKT
conditions. Numerical results under two network scenarios are also calculated.
These results reveal that compared with strict-priority scheduling, still
highest priority is provided for VoIP traffic, however, no strict priority
should be given for IPTV traffic since it will conflict with NUM objective. It
is expected that our results will shed lights on the evolvement towards the
converged network.
