Title:   GeoQuorums: Implementing Atomic Memory in Ad Hoc Networks 

Speaker: Seth Gilbert

Place:   NE43-308
Time:    1-2:30pm
Date:    May 2, 2003

Abstract:

In this talk, I will present a new approach for implementing atomic
read/write shared memory in adhoc networks.  These networks are, by
nature, highly dynamic, and it is therefore difficult to employ
classical distributed algorithms.  As a result, we divide the problem
into two components.  First, we define a geographic abstraction,
associating virtual processes with physical regions, known as "focal
points", and we show how mobile hosts can implement this abstraction.
Second, we present an atomic memory algorithm that depends on quorums
of focal points to replicate the data, ensuring fault tolerance and
consistency.  The final algorithm, while tolerating much dynamic
behavior, is comparable to - and in some cases an improvement on -
other read/write shared memory: it supports single-phase write
operations, read operations often only require a single phase, and
limited reconfiguration is allowed, primarily for performance
optimization.