S

CS 5380 Software Engineering

Chapter 10 Sociotechnical

Systems

Section 2 of book

Section 2: Dependability and Security

Introductory statement Dependability and Security can be more important

than functionality Insulin pump Ancestry.com Voter targeting MS Word Flight controller

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Systems

Author: A system is a purposeful collection of interrelated components of different kinds which work together to achieve some objective

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SocioTechnical Systems

Term since 1950s

System of more than hardware and software

Factors People Processes Laws, Regulations Organizaitons Physical Environment

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SocioTechnical SystemStack

Sociotechnical System Stack Equipment Operating System Communications and data management Application layer Business Process layer Organizational layer Social Layer

Issues in one area affect others

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Factors

Factors that affect the entire system (at creation or change) Process changes

Do you require a process change for a new s/w system? Desired change in process drives change

Job changes new roles obsolete roles

Organizational / political Important/unimportant roles

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Characteristicsof SocioTechnical Systems

Emergent properties Appear after system starts

Nondeterministic Hardware generally deterministic Software may change Other factors are hard to control

Acceptability of system will change due to various factors

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Emergent System Property

Emergent system properties Appear after systems implemented

CAD systems Multiple vendors No universal interchange format Attempts – plotting, consortium Autodesk file format

Initially, just another format After market share achieved, defacto standard

Level of sociotechnical system stack?

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Emergent System Properties

Email

Until a sufficient population has the same technology, it is not accepted.

Collective understanding of email affects its use Etiquette (forwarding, tone) Attachments Standards of organizations

Security Storage allowances

Level of Sociotechnical Systems Stack?Chapter 10 – Socio Technical Systems9

Non Determinism

Voter tracking database

Created by incorporation of data from States Counties Data providers

Standardization of formats limited USPS, yes. Few follow the rules

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Multilevel Issues

Integration of data from diverse sources Different formats (csv, fixed cell, spreadsheet) Different intents (employee list, parent list, band

booster) Different standards of quality (employee list, band

booster, voter file) Different standards of content (fields – name,

address, phone, zip)

Human errors

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Wicked Problems

No clear solution Contradictory requirements Changing requirements Too many stakeholders

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Gradebook System

Goal: coordinate gradebook information.

Master Database of Teachers, Classes, Students, Grades

Individual database at teacher computer

Periodic grade reporting electronically Pre- internet Data card

Issues Acceptance, training, integration

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GIS System

Geograpic Information System

Datanbase of geographic features Streets Properties, Ownership, Easements Gas, Electric, Phone lines Political Boundaries (precincts, zip codes, …)

Uses Right of way procurements Maintenance – digging Public announcements

Issues: Usability of system before data set up

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Group Exercise

Distributed in class

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Stages

Procurement

Development

Operation

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