Delay Performance of CSMA
policies in Multihop Wireless Networks: A New Perspective
Mahdi Lotfinezhad
Department of Computer Science
University of Toronto
Thursday, May 11,
3pm
Location:
BAB025 (Bahen Centre
Basement)
Abstract:
This talk focuses on the
delay performance of CSMA policies in wireless networks, where the delay is
defined as the average time that a silent wireless link needs to wait until it
accesses the channel for packet transmission. It is well-known that CSMA
policies can incur an access delay that may be correlated over time and may
grow exponentially with the network size. This discourages practical
implementation of CSMA policies in even mid-sized networks. This talk provides
a new perspective on the delay performance of CSMA policies. It presents
recently developed results for two important interference models and show how
CSMA policies can be used to ensure an access delay that is memoryless over
time or that does not grow with the network size. The two interference models
that we consider are primary interference and the ``lattice interference
graph''. The results presented suggest that CSMA policies can achieve a delay
performance, as well as a delay-throughput trade-off, that makes them viable
to be used in practice. These results find further applications in the
analysis of percolative systems.
Bio:
Mahdi
Lotfinezhad received the B.Sc. degree in electrical engineering from the Sharif
University of Technology in 2003, and the M.A.Sc. and Ph.D. degrees from the
University of Toronto in 2004 and 2009, both in electrical and computer
engineering. He is currently a post doctoral fellow in the department of
Computer Science at University of Toronto. His doctoral research has focused on
the complexity and stability properties of scheduling policies in wireless
networks with time-varying channels and populations. His current focus is on the
convergence and delay properties of CSMA random access policies.
Host of Talk:
Peter Marbach (marbach@cs.toronto.edu)