More Related Content Similar to Quality Re Pres Ebert Rudorfer Med Conf2011 V5 (20) More from Arnold Rudorfer (10) Quality Re Pres Ebert Rudorfer Med Conf2011 V51. Quality Requirements
Engineering for
Medical Systems
MedConf 2011
Munich, 05. October 2011
© 2011 Siemens Healthcare Diagnostics Inc. All rights reserved.
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 1
2. Contents
Goals
Brief Look on Siemens and Vector
Business and Environment
Quality Requirements Engineering
Results and Summary
Further Information
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 2
3. Goals
Provide an overview on quality
requirements engineering challenges
in a medical device project
Apply quality requirements
engineering for a critical system
Share experiences how quality
requirements can be successfully
addressed
Show lessons learned and achieved
benefits
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 3
4. Contents
Goals
Brief Look on Siemens and Vector
Business and Environment
Quality Requirements Engineering
Results and Summary
Further Information
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 4
5. Siemens Healthcare
In vivo diagnostics (imaging)
X-Ray Computed Magnetic Molecular Ultrasound Oncology
Tomography Resonance Imaging
IT Solutions
In vitro diagnostics (laboratory systems)
Immunoassay Molecular Clinical Chemistry Hematology Urinalysis Lab Automation Point of Care
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 5
6. Vector Consulting Services
Your Partner in Achieving Engineering Excellence
… offers a comprehensive consulting and
training portfolio as well as process tools for Automotive
optimizing product development
… serves industries such as automotive, Aviation
aviation, IT and telecom, machinery and & Defense
plants, medical, and railway
IT & Telecom
… is supporting clients on efficiency
improvement, PLM/ALM, functional safety,
CMMI/SPICE, requirements engineering and Machinery
product management & Plants
… as a group serves companies across the Medical
world, with over 1000 employees and sales of
well over 150 Mio € pa
Railway
www.vector.com/consulting
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 6
7. Contents
Goals
Brief Look on Siemens and Vector
Business and Environment
Quality Requirements Engineering
Results and Summary
Further Information
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 7
8. Business Challenges
Environment:
Shorten time-to-market
Cuts in healthcare budgets
Continuous product innovation
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 8
9. Business Challenges
Product:
Safety-critical: Critical for health and
sustainability
(e.g. bodily injuries, wrong treatment)
Security-critical: Critical for
preserving information integrity
(e.g. access to sensitive data)
Mission-critical: Critical for mission
continuity
(e.g. unavailability)
Business-critical: Critical for
business success
(e.g. damage to image)
Critical need for quality
requirements engineering
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 9
10. Contents
Goals
Brief Look on Siemens and Vector
Business and Environment
Quality Requirements Engineering
Results and Summary
Further Information
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 10
11. Quality Requirements Engineering (QRE):
Overview
Quality Requirements (QR)
A quality requirement describes a qualitative property that a system
or individual component of the system must exhibit. Sometimes
called: non-functional requirements.
They extend the functional requirements.
Examples: Availability, maintainability, security, reliability.
Quality Requirements Engineering (QRE)
The disciplined and systematic approach to elicit, specify, analyze,
prioritize, commit, verify, validate, assure and manage quality
requirements throughout the life-cycle.
Focus areas: Systems engineering, processes and product life-
cycle
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 11
12. QRE: Focus on Systems engineering,
processes and product life-cycle
Systems
Engineering
Product
Processes
Life-Cycle
Quality Requirements Engineering (QRE) needs to balance
systems perspective and business needs.
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 12
13. Quality Requirements Engineering (QRE):
Example: Security
Life-Cycle Perspective Life-Cycle
Security requirements
Environmental analysis Incident / risk alerts
Operational threats Failure analysis
Misuse Cases Risk assessment Patch management
System analysis Architectures,
System design components Security assessments
Verification Test scenarios Design for security System test
Security archi- Guidelines, standards Validation
Subsystem analysis tecture design Common criteria System integration
Subsystem design
Verification Security review
Penetration tests
SW Analysis Subsystem test
SW design Test driven Subsystem integration
Verification development
Checklists
Software- / Hardware SW- / HW- test
Implementation and SW- / HW- integration
Verification Code analysis
Security reviews
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 13
14. Quality Requirements Engineering (QRE):
Example: Security
Systems
Security architecture and design Engineering
Develop security architecture on system level
Keep architecture as simple as possible
Adaptation of existing building blocks is difficult
Implementation
Create and use proven software components
Use coding standards, guidelines
Employ tools for static analysis, fix compiler warning causes
Consider quality requirements as a system property.
Use different means to prevent critical defects.
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 14
15. Quality Requirements Engineering (QRE):
Example: Security
Systems
Engineering
Security verification:
Security reviews on all security-relevant artifacts
Tests and simulations
Security validation:
Validation tests (completeness, correctness) – can be
handled in context of “normal” validation
Penetration tests (vulnerabilities) – high manual effort,
requires specific expertise
Strive for detection of potential weaknesses and insufficient
implementation at the earliest possible point of time.
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 15
16. Quality Requirements Engineering (QRE):
Example: Security
Example: Simulation / test of a security protocol
Systems
Engineering
Test Cases
Security
Protocol
Test Results
Design
Specification
Simulation / Test
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 16
17. Quality Requirements Engineering (QRE):
Example: Security
Activity Benefit Processes
Adapt mature development Security engineering activities are known,
processes to factor in scheduled, and executed within “normal” development.
security engineering. Security is not treated as add-on.
Synergies can be exploited.
Elicit security requirements Assets to be protected are clearly identified.
in the beginning of the Basis for realization of security.
project. Test cases for security validation can be deduced.
Review or test every security Identification of issues at the earliest possible time.
relevant artifact, use analysis Automated tools increase confidence and reduce effort.
and test tools.
Manage embedded security Specific embedded security expertise available when necessary.
competencies.
Quality requirements engineering is deeply engrained
in systematic requirements engineering
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 17
18. Large-Scale Medical Device Projects
Project Overview
Several thousand single
product requirements
Several million lines of code
Several hundred developers
in 5+ locations worldwide
Multi-fold clinical applications
Source: H IM
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 18
19. Case Study: Embed Quality Requirements
Engineering into an Existing RE process
Selected Issues Solutions
Feature model
Difficult mapping of
requirements to existing Value-based ranking of
platform QR
• Identification of customer Architecture Model
value Mapping
• Controlling architectural Quality Tree
complexity
• NFRs difficult to define
Source: H IM
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 19
20. Issue 1: Mapping of requirements to
Platform – Solution “Feature Model”
Highest Level
Benefits:
Higher level abstraction of grouping of
requirements into sellable units: From 5,000
product requirements to 800+ features
(*) Source: Estimates from product managers
(factor ~ 6)
Visual domain model for healthcare
workflows (tree & graphical)
Graphical View Reduction of (de-) scoping effort by ~ 30% (*)
Reduction in time to understand aspects of
the system
Hierarchical relationships enable mapping of
stakeholder requests and visualize
dependencies
Basis for introducing variability management
Hierarchical View Feeds the product backlog
Source: H IM
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 20
21. Issue 2: Identification of customer value –
Solution “Forced Ranking”
Characteristics:
Ranking is used to determine the release
backlog
Main criteria for ranking are business value,
technical risk and effort
Benefits:
Only features with the highest business
value (and feasibility) are implemented
Feature independence assures
parallelization of development
Simulation of optimal release plan (what-
if analysis)
Source: H IM
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 21
22. Issue 3: Controlling – Solution
“Architecture Model Mapping”
F Feature Model Characteristics:
Identifies links between features and their
F F F
implementation
SWF SWF SWF SWF SWF SWF SWF Explicit modeling of variability in the architecture
S Architecture Model
Benefits:
SS SS SS
Architectural decisions motivated by features
C C C C C C and product-line variability
Enable reduction of architectural complexity
Support impact analysis for (de-) scoping
sessions
Early identification of architectural risks
Improved accuracy of early effort estimates
Reduction of number of scoping sessions
Source: H IM
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 22
23. Issue 4: NFRs difficult to define for
platform – Solution “Quality Tree”
Characteristics:
Example Quality Tree - Extract
Quality requirements most challenging to
define (subjective, domain-specific)
Quality Tree provides an effective means
for collecting and prioritizing qualities
Analysis technique based on business
drivers, key usage scenarios and
international standards
Benefits:
Identification of key architectural risks to
consider
Example: Learnability
Transparency of qualities‘ definition to all
Learning time of an educated physician stakeholders
shall be less than x minutes ...
Explicit link of business drivers and
platform architecture
Source: H IM
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 23
24. Contents
Goals
Brief Look on Siemens and Vector
Business and Environment
Quality Requirements Engineering
Results and Summary
Further Information
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 24
25. Quality Requirements Engineering
Impacts on Requirements
Engineering
Value orientation 1. Understand valuation of quality
Global competition requirements
Cost pressure 2. Consistently prioritize
Shorter Life-Cycles 3. Address system context
Reliability
4. Stay agile and lean
Safety
Resilience 5. Model quality requirements end-
Serviceability to-end
Complexity 6. Systematically build quality
Auditability 7. Manage knowledge
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 25
26. Results
Quality Requirements Engineering Pays Off
Improved system availability and
reliability
Ca. 30% Reduction of review
effort due to early feature reviews
vis-a-vis quality requirements
Ca. 25% reduction of upfront
requirement engineering work
due to incremental requirements
engineering
Use of quality tree assures a clear
focus on future customer needs
and elimination of unnecessary
redesigns
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 26
27. Key Take-Aways
Successful development of critical systems requires a business-driven
requirements engineering approach with specific consideration of quality
requirements
A value-feature perspective for functional and quality requirements allows
tracing business needs to implementation details
Introducing a platform concept means to restructure quality requirements
and link them to architecture components
Continuous assessment and verification of business needs is necessary to
judge priorities of quality requirements
Consequent quality requirements engineering needs profound organizational
change management to facilitate cross-cutting perspectives, innovative
methodologies and collaboration
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 27
28. Thank you for your attention!
Copyright © Siemens AG 2011. All rights reserved.
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 28
29. Contents
Goals
Brief Look on Siemens and Vector
Business and Environment
Quality Requirements Engineering
Results and Summary
Further Information
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 29
30. Documented Experiences and Best Practices
from various Industry Projects
English language:
Software & Systems
Requirements
Engineering: In Practice
2009
McGrawHill
German language:
Systematisches
Requirements
Engineering
Third edition, 2010
Dpunkt.verlag
Link to web site McGrawHill Link to web site Dpunkt
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 30
31. Arnold Rudorfer
Program Manager Platform
Development
Siemens Healthcare Diagnostics
62 Flanders Bartley Road
Flanders, NJ, 07836
Phone: +1 973 927 28 28
Mobile: +1 609 954 23 84
Email:
arnold.rudorfer@siemens.com
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 31
32. Dr. Christof Ebert
Managing Director
Vector Consulting Services GmbH
Ingersheimerstrasse 24
D-70499 Stuttgart
Phone: +49 711 – 80670-175
Fax: +49 711 – 86070-444
Email:
christof.ebert@vector.com
© 2011 Siemens Healthcare Diagnostics Inc. Arnold Rudorfer, Siemens Healthcare Diagnostics, Christof Ebert, Vector Consulting Page 32