This talk explains the SoSA method and how it can scope the complexity of the problem of designing for software solutions to realize sustainability goals.

1. Designing Software with a Sustainability Intent!
The Software Sustainability Assessment!
SoSA© method!
!
!
!
Patricia Lago!
Vrije Universiteit Amsterdam

2. WHAT DO THESE PROJECTS HAVE IN COMMON?

3. #1: THIS IS WHAT MAKES SOCIETY A BETTER PLACE
#2: SOFTWARE IS THERE TO MAKE THE DREAM COME TRUE

4. ‹#› Het begint met een idee
Are we looking at the right problems?
Do we have the right instruments?
Source: Dorian Gray (2009), the mo?on picture
PATRICIA LAGO ©2016

5. A (simple) example:
Smart Healthcare and Medication Reminder Apps
“Smart Healthcare is defined by the
Technology that leads to be7er
diagnos8c tools, be7er treatment
for pa8ents, and devices that
improve the quality of life for
anyone and everyone.”
Source: bluestream.sg/smart-healthcare

6. Education: Computer Science Master Track
Software Engineering and Green IT
P. Lago, A Master Program on Engineering Energy-Aware SoIware. In Interna8onal Conference on
Informa8cs for Environmental Protec8on, BIS Verlag, 2014.

7. The Green Lab
A master course for serious experimentation in software energy
efficiency
research education
practice
“encourage critical and
interdisciplinary thinking”
“experiment with new
methods”
“pose
sustainability
challenges and
needs”
© Patricia Lago 2014

8. RESEARCH PHILOSOPHY

9. OPTIMIZED DATA MANAGEMENT
+70% performance
WEBSITE CONTENT DELIVERY
-45% energy consumption
SMART USE OF WEB RESOURCES
-8,5% energy consumption
SOFTWARE DEPLOYMENT
STRATEGY
-10% power consumption
RESULTS FROM CASE STUDIES
FLEXIBLE COMPUTATION
OFFLOAD
-40% power consumption
SOFTWARE REFACTORING
-50% energy consumption
-20% power consumption
EFFICIENT DATABASE QUERIES
-25% energy consumption
PATRICIA LAGO ©2016, 2017

10. KNOWLEDGE BANK REUSABLE METRICS / KPIs
RESEARCH: Plan for software sustainability
PATRICIA LAGO ©2016, 2017

11. SoSA method:
DECISION MAP
RQ: How to Plan for Software to be “Sustainable by Design”?
PATRICIA LAGO ©2016, 2017
SW ARCHITECTURE DESIGN

12. Software intent:
“the fundamental laws that capture a software system’s intended
behavior”
[Huisman et al, Software that meets its intent, 2016]
PATRICIA LAGO ©2016

13. Technical Economic
SocialEnvironmental
Source: P. Lago et al. “Framing Sustainability as a SoIware Quality Property”, ACM
Communica8ons, 2015.
Software with a sustainability intent: intended
sustainability behavior”

14. Four relevant sustainability concerns
Technical
Economic
Social
Environmental
PATRICIA LAGO ©2016

15. Sustainability Defined
u Technical Sustainability addresses
the long-term use of software-
intensive systems and their
appropriate evolution in an
execution environment that
continuously changes.
u Economic Sustainability focuses
o n p r e s e r v i n g c a p i t a l a n d
(economic) value.
u Social Sustainability focuses on
supporting current and future
generations to have the same or
greater access to social resources
by pursuing generational equity. For
software-intensive systems, this
dimension encompasses the direct
support of social communities in
any domain, as well as the support
of activities or processes that
indirectly create benefits for social
communities.
u Environmental Sustainability aims
at improving human welfare while
protecting natural resources. For
software-intensive systems, this
dimension aims at addressing
ecologic requirements, including
energy efficiency and ecologic
awareness creation.
Source: P. Lago et al., Framing Sustainability as a Software Quality Property, ACM Communications, 2015.

16. Impacts Defined
◆ Immediate impacts refer to changes which are immediately observable.
◆ Enabling impacts arise from use over time. This includes the opportunity to
consume more (or less) resources, but also shorten their useful life by
obsolescence (when we buy a new smart phone just because incompatible
with newer applications) or substitution (when e-book readers replace printed
books).
◆ Systemic impacts refer to persistent changes observable at the macro level.
This includes behavioral change and economic structural change. This may
translate into (negative) rebound effects by converting efficiency
improvements into additional consumption, or new risks - like our
dependence on ICT networks that makes a digital society also vulnerable.
Source: L. Hilty et al. The relevance of information and communication technologies for environmental
sustainability. Environm. Modelling & Software, 21(11):1618-1629, 2006.

17. TECHNICAL
ECONOMIC
SOCIAL
ENVIRONMENTAL
software
IMMEDIATE IMPACT
ENABLING IMPACT
SYSTEMIC IMPACT
PATRICIA LAGO ©2016

18. SOFTWARE SUSTAINABILITY ASSESSMENT METHOD © PATRICIA LAGO
PATRICIA LAGO ©2016
IMMEDIATE
IMPACT
Software
Product
Software with a sustainability intent:
A multi-dimensional problem over time

19. SYSTEMIC
IMPACT
ENABLING
IMPACT
SOFTWARE SUSTAINABILITY ASSESSMENT METHOD © PATRICIA LAGO
PATRICIA LAGO ©2016
IMMEDIATE
IMPACT
Software
Product
Software with a sustainability intent:
A multi-dimensional problem over time

20. TECHNICAL
ECONOMIC
SOCIAL
ENVIRONMENTAL
IMMEDIATE
IMPACT
ENABLING
IMPACT
SYSTEMIC
IMPACT
ENERGY
SAVINGS
SCALABILITY
CONFIGURABILITY
SOFTWARE SYSTAINABILITY ASSESSMENT METHOD © PATRICIA LAGO
WELL BEING
HEATHCARE
SAVINGS
ENERGY
COSTS
Smart
Lighting
PATRICIA LAGO ©2016
PHILIPS SOFTWARE for SMART LIGHTING CONTROL
+
+
-
+
+/- +/-
An example

21. Identify scope
of
sustainability
impact …
Assign
indicators
Software
solution
… in the pertinent
sustainability dimension
Drivers, goals,
quality properties
Going from a software solution to its sustainability
impact
PATRICIA LAGO ©2016

22. Identify scope
of
sustainability
impact …
Assign
indicators
Software
solution
… in the pertinent
sustainability dimension
Going from a software solution to its sustainability
impact
Architecture/Concernsà Dimensions à Indicators à Metrics/KPIs
à Measures à Decision Map
Drivers, goals,
quality properties
PATRICIA LAGO ©2016

23. TECHNICAL
ECONOMIC
SOCIAL
ENVIRONMENTAL
IMMEDIATE
IMPACT
ENABLING
IMPACT
SYSTEMIC
IMPACT
KPMG
(Qubus)
POWER
CONSUMPTION
EXECUTION
TIME
(data load)ENERGY
CONSUMPTION
(deployment
strategy) 10%
+/- +/-
Architecture/Concerns à Dimensions à Indicators à Metrics/
KPIs à Measures à Decision Map
Another example
Source: R. Verdecchia et al., Estimating Energy Impact of Software Releases and Deployment Strategies: the
KPMG Case Study, in ESEM 2017, to appear.

24. Another example: Mobility as a
Service
PATRICIA LAGO ©2016

25. SoSA Model MaaS Framework: the mobility end-user perspective
Source: T. Niggebrugge, S. Vos, P. Lago. The Sustainability of Mobility as a Service Solutions -
Evaluated through the SoSA Method, work in progress, July 2017.
PATRICIA LAGO ©2016

26. SoSA Model MaaS Framework: the mobility provider perspective
Source: T. Niggebrugge, S. Vos, P. Lago. The Sustainability of Mobility as a Service Solutions -
Evaluated through the SoSA Method, work in progress, July 2017.
PATRICIA LAGO ©2016

27. Thank you
28@patricia_lago
Credits: slides, ideas and results are a collec8ve effort
with my bright and energe8c colleagues in the S2
Group @Vrije Universiteit Amsterdam
www.s2group.cs.vu.nl