Erasure Coding for Distributed Storage Systems
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This seminar is part of the "EBSIS - Event Based Systems in Iasi" Twinning project. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 692178.
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ABSTRACT
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A huge quantity of data is generated and stored every day. Preeminent 
examples are the 300 million photos that get daily uploaded to Facebook 
or the 156 million emails sent every minute, just think that almost 90% 
of the data in the world was generated in the last 2 years.
Such data do not settle in the user's machine: they are hosted in data 
centers which must be able to serve them upon request. Hence, a 
paramount property for distributed storage systems is reliability, which 
can be insured carefully introducing redundancy in the system to be able 
to tolerate adverse situations. To this aim, erasure coding techniques 
optimizing the storage overhead - fault tolerance tradeoff have been 
used in production systems for many years.
Only recently, the winds of change have begun to blow, e.g. a local 
reconstruction code has been introduced in Microsoft Azure in 2012, 
creating wide space to a number of erasure coding techniques studied 
during the last 10/20 years. Indeed, more metrics other than fault 
tolerance and storage overhead are now considered, e.g., repair 
bandwidth, disk I/O, repair locality, together with encoding and 
decoding performance. As it is not possible to optimize all of them at 
the same time, the optimal code depends on the particular application.
In this talk, we focus on the understanding of the different metrics to 
evaluate erasure codes and how they affect the use-case of storage 
systems. Then, we study how to introduce data entanglement on top of the 
coding technique to enhance desirable properties of the resulting system.
          
SPEAKER(S)
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BARBI Roberta
University of Neuchatel
Elvetia
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Roberta Barbi got a Bachelor Degree in Applied Mathematics 
from the University of Verona (Italy) in 2013 and a 
Master Degree in Mathematics with a minor in coding theory 
and cryptography from the University of Trento (Italy) in 
December 2015. She started the PhD at the University of 
Neuchatel in January 2016 and she expects to defend by 
February 2019.
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