Quality Attributes
by Christopher Grant
christopher_grant@homedepot.com
https://www.linkedin.com/in/christophergrant
Agenda
• Intro	&	Overview
• IASA	Quality	Attributes
• Balancing	&	Tradeoffs
Core Reading
Materials	Covered	in	this	session	
support	Chapter	5	from	your	
IASA	ITABOK— IT	Architecture	
Body	of	Knowledge	book
IASA Skills Taxonomy
Foundation	Body	of	Knowledge
Software	
Architecture
Infrastructure
Architecture
Information	
Architecture
Business
Architecture
Enterprise	Architecture
Business	Technology	Strategy
IT	Environment
Quality	Attributes
Human	Dynamics
Design
5	foundation	
Pillars
Specialization
What is quality
The standard of something as measured
against other things of a similar kind; the
degree of excellence of something.
- Google
Quality attributes across industries
• All	industries	measure	the	quality	of	their	products
• Whole	organizations	are	devoted	to	measuring	quality
• Attributes	are	defined,	measured	and	monitored
• Consider	potential	quality	attributes
for	the	following	four	industries
– Clothing	Manufacturing
– Food	Manufacturing
– Shipping	&	Delivery
– Furniture	&	Bedding
Quality in Clothing Manufacturing
• Color
• Durability
• Stitching
Quality in Food Manufacturing
• Color	/	Appearance
• Flavor
• Firmness
Quality in Shipping & Delivery
• Processing	Time
• Time	in	transit
• Delivery	condition
Quality in Furniture & Bedding
• Comfort
• Durability
• Safety
What might some key IT attributes be for:
• Space	Satellite
• Financial	Trading	
• Game	
• Mobile	
• Open	Source	
• CMS	/	Website	Builder
Architecture Quality Attributes
Quality Attributes in IT Architecture
A	quality	attribute	is	a	non-functional	
characteristic	of	a	component	or	a	system.	It	
represents	a	cross-cutting	architectural	concern	
for	a	system	or	system	of	systems.	
- IASA
Quality Attributes
Number	of	9’s Yearly	
Downtime
3	Nines	(99.9%) ~9	hours
4	Nines	
(99.99%)
~1	hour
5	Nines	
(99.999%)
~	5	minutes
6	Nines	
(999.999%)
~31	seconds
24/7 0
Must	be	measurable,	monitored…
Availability		Measures
Also known as the *ilities
IASA Groupings
Usage:
• Usability
• Localization
• Accessibility
• Personalization
• Customizability
Development:
• Manageability
• Maintainability
• Supportability
• Extensibility
• Flexibility
Operation:
• Performance
• Reliability
• Availability
• Scalability
Security
Usage
How	your	user	interacts	
with	your	system.
Concepts
- Usability
- Localization
- Accessibility
Development (or support)
How	the	system	is	constructed	to	
enable	future	needs	and	support
Concepts
• Flexibility
• Customizability
• Supportability	
• Maintainability	
• Extensibility
Operation Discussion
How	the	system	will	react	in	it's	running	state
Concepts
• Performance	
• Scalability	
• Reliability	
• Availability
Security Discussion
Protecting	your	user's	data	and	ensuring	
continuity	in	the	state	of	your	system
Concepts
• Physical
• Network	
• Platform
• Monitoring
• Standards
Packaging & Deployment Discussion
The	expectations,	process,	and	management	of	IT	
products	following	the	completion	of	development	and	
prior	to	“normal”	day-to-day	operating	conditions
• Ensures	project	requirements	are
successfully	delivered	to	prod
• Ensures	delivery	of	Quality
Attributes	to	prod
• Not	just	the	features	but	also	
how	well	they	are	delivered
Monitoring & Management Discussion
Monitoring	&	Managing	quality	attributes	in	a	
standard	and	objective	way	
• Problem	analysis
• Capacity	planning
• Service	level	agreement	(SLA)	
• Issue	response	techniques
• Integrate	metrics	with	processes
Attribute Balancing & Project Tradeoffs
Balancing Quality Attributes
• Achieving	high	levels	of	quality	attributes	may	be	
costly	or	prohibitive
• Improving	one	attribute	may	impact	another
• It’s	important	to	understand	requirements	upfront
Attribute Trade-offs
• Architectural	decisions	that	may	impact	more	than	
one	attribute	are	called	trade-off	points.	
Flexibility FlexibilityFlexibility
Personalization Localization Maintainability
Complementary Neutral Negative
Trade off Matrix
Trade-off decision: Not encrypting data streaming
Drone:	$4.5M
Hack:	$26.00
Project trade-offs
• Time,	cost,	requirement,	&	resources	constraints	can	
become	a	trade	off	in	applying	quality	attributes
Identifying and prioritizing requirements
• Arrange	attributes	by	group
• Prioritize	by	importance	and	
complexity
• Review	trade-off	points
• Balance	requirements	against	
trade-offs,	cost	and	time
Review
• Quality	Attributes	are	critical	for	the	success	of	your	
architecture
• Iasa groups	attributes	into	4	groupings
– Usage
– Development	
– Operation
– Security
• Consideration	of	packaging/deployment	and	
monitoring/management	helps	ensure	attributes	are	effective	
while	they	system	is	in	use
• Requiring	excellence	from	all	attributes	may	be	costly	or	
prohibitive.	Review	attribute	impacts	and	trade	offs	to	
balance	needs	of	the	project

IASA Architecture Pillars - Quality Attributes