EM.413 Bruce Cameron System Architecture meeting
Industry platforms
Differentiating between suppliers and partners in a two sided market
Partners
earn proportionally to your revenue
has access to your customers
no contractual obligation
has network effects
Suppliers
earn directly from you
detached from your customers
contractually bound
no network effects
Network effects
actions by others create value for you
eg
my mom joining a network means I can call her for free
how much does an additional user increase the value of other users
how much does an additional user increase the demand for the other market side
Feel the marble
opening up your environment, others need to believe
rules will be evenly enforced
you won’t compete against them
Industry platforms are high risk
Only 17% succeed (sample of 250 firms)
average lifetime 5 years
reasons
mispricing on one side
failure to develop trust
prematurely dismissing competition
entering too late
https://hbr.org/2019/05/a-study-of-more-than-250-platforms-reveals-why-most-fail
Open architecture
Distributed contributions
Stated open not always open in practice
Are DSMs just categories?
every connection is an arrow
category theory
MIT/SDM/Thesis Ideas
Dan Sturtevant
SDM Thesis Ideas
EM.413 program management meeting
Bryan Moser
Project design for flexibility
don’t ask for one plan, ask for a thousand plans
enabled by model based approach
what is the form of the plan?
can it be close to the
James Lyneis
Adaptive resource control
EM.413 System Architecture
Dan Sturtevant on software architecture
focused on software
Only 7% of projects are successful
on schedule, budget, good functionality, not abandoned
code has structure, but it’s not three dimensional
this makes it harder to understand the structural problems in code
Three dimensions are natural, two dimensions are efficient.
code is like taking knowledge and encapsulating it into functionality
emergent properties
usually bad
usually result in emergencies
define and enforce design rules
there’s often a difference between how the engineers think the code is structured and how it actually is
engineers disagree and code scanning shows a different result
Modular Design
Entropy happens to codebases to make them undesigned, less modular
Design Rules: The Power of Modularity by Carliss Baldwin and Kim Clark
if you have a technical system that’s highly modular is like creating an evolutionary system
similar to organs
DSM and network view can be isomorphic
DSM allows you to compress a lot of information a network view would be too complicated to view
can see API, shared code, hierarchy, complexity
dependencies across modules both above and below the diagonal shows bad hierarchy
see Joel Moses for work on network representations MIT
Question
Do you find that codebases that lean harder on Functional Programming concepts (like immutability, reduced side effects) produce more modular?
Systems want to be more tightly integrated if there are parts performing multiple functions
Hardware systems it’s more common to tightly integrate for operational efficiency
I suspect interfaces have more energy loss in hardware systems than in software systems
It’s not enough to say the baby is ugly, eventually you need to tell them how to get the baby a nose job.
modules could be mapped to files / functions
like type safety for architecture
->
Make your architecture type safe
restrict use of modules to the API
Apparently distributed organizations build more modular systems…
his company does this analysis on code
Silverthread
https://www.silverthreadinc.com/white-papers
can consider this for thesis, Dan Sturtevant would consider advising
Takeaways
architecture is meant to promote understandability and evolvability
architecture health is holistic, code health is reductive
both valuable
Dan Sturtevant wrote an article on Modular Design is required for Agile development
EM.413 program management meeting Bryan Moser
multi project program management
some semantics
program
set of projects related by objective
portfolio
set of projects considered for collective performance, but not necessarily coupled by objective
optimizing resource allocation is np-hard
requires heuristics
some priority rules
FIFO
shortest operation first
maximum operation first
minimum slack
maximum slack
shortest activity from shortest project
longest activity from longest project
minimum total work content
maximum total work content
random
lol
max total work content and earliest late start time
EM.413 meeting Bruce Cameron System Architecture
Tradespaces
Tradespaces are really just a list of feasible concepts
Sensitivity vs connectivity
tests for architectural decisions
architectural decision vs design decision
architectural decisions are more sensitive and more connected
not a categorical difference between architectural and design decisions
architectural decisions are a subset of design decisions
Talk by Morgan Dwyer
EM.413 Eric Rebentisch System Engineering meeting
Thinking about how changes propagate throughout the system
Change Propagation Index
Rule of thumb
Every milestone multiplies the cost of change by 10
EM.413 meeting program management Bryan Moser
Project design for alignment
If all events are independent, no alignment needed
Dependencies are satisfied through coordination
but simplified dependencies can reduce the need for coordination
Using DSM to “unplanned iterations”
less clustered DSMs might be better candidates for Agile development
EM.413 program management Bryan Moser meeting
Questions in the design of complex projects
Is the project designed to be stable and predictable?
Project Control
Cost of reporting needs to have some return in the form of a change in process
otherwise reporting will stop
Earned Value
Made up of
Budgeted Cost
Actual Cost
Work Performed
Work Scheduled
brief discussion about Entropy again as it relates to code
Does software need separate architecture?
other engineering disciplines need to build architectures separately, but this doesn’t happen in code
I think that’s partially because code, in principle, contains the architecture. It’s the essence of designing the system
this doesn’t mean it’s actually easy to extract that, and that’s what Dan Sturtevant is working on
ways to organize an org
functional
business units
or both
Benefits of commonality
similar vs identical
80% sharing is much less useful than identical
even 99% sharing still requires two items in inventory
benefits of similarity is often over estimated, but benefits of commonality generally is under estimated (especially for identical)
Principles of System Architecture
Language is the interface of the mind
EM.413 System Engineering meeting Eric Rebentisch
Systems in the service industry
Attributes of a system
Intagible
non physical
Heterogenous
sociotechnical factors mean delivery and experience will vary
Inseparable
value provided at time of interaction
Perishable
value does not exist unless produced
Key system concepts
co creation of value between offeror and beneficiary
time and place dependent
to what degree is MIX a service?
Product-service systems as a gradient
many systems are part product, part service
from peer who worked at Planet labs
planet labs reframed the problem of building a satellite into serving the data from a satellite
when you think in the solution neutral space, you can see opportunities to reframe products as services
Design of services
what response are you aiming for
Disneyland is a service
digital twin
types
data travels between digital and physical automatically
digital shadow
data flows automatically from physical to digital, manual in inverse direction
digital model
manual data flow in both directions
examples
google maps
digital twin?
uses traffic data
value seems to be determined by how the flow of data is organized from physical to digital
EM.413 System Engineering Eric Rebentisch meeting
John Thomas presenting on system safety and security
Single loop vs double loop learning
Single Loop
What happened?
What did we do?
Two mistakes can appear different though the same methodology led to both
Double Loop
Why did we do this?
Reliability Block Diagram
shows redundancies
used in Fault Tree Analysis
Systems Theoretic Process Analysis
Define purpose of analysis
Model of control structure
Identify unsafe control actions
Identify loss scenarios
EM.413 meeting program management James Lyneis
project design for quality
Makes me think of zen and the art of motorcycle maintenance
Grade vs quality
Grade is determined by scope
What you’re building
Quality is determined by defects
How well you built
Quality dynamics
Rework as a function of quality
Change
Emergent change
A problem with meeting existing requirements
Not sure that “emergent” is the best descriptor here
Initiated change
Based off a change in requirements
Am important takeaway
Adding resources can increase delay
Brook’s Law
Asking a question is like drawing a vector
The answer extrapolates from the direction of the vector
This explains why asking a question often involves additional clauses to help fine tune the vector direction so it doesn’t set the respondent off in an unintended direction
Put a model diagram on your wall
Inspired by example from F-18 project
Truly novel projects are hard to predict what requirements are actually valuable
Excess work in models?
EM.413 meeting Bryan Moser program management
Denver airport and rail case study
Ted Halsey
Worked on courthouses
Airport
Planned to have new, efficient baggage handling system
September 2005 they finally gave up on this
BAE went out of business after this
Construction started November 1989
Planned to end October 29 1993
expert opinion
based on funding cycles and bond paybacks
Fastracks train line from Union Station to the Airport
thinking about Induced Demand
increasing capacity may not always prove to increase utilization, if the corridor is in a complex system that has other moving parts
this may be the best argument against assuming Induced Demand is ubiquitous and inevitable
maybe Durham should provide gantt charts for all projects
Initial screening involved a lot of reality checking to reduce ~100 possible routes over the first 4-6 months in Dec 2003
Issues with signaling and satellite system at at-grade crossings
thinking about the RTD vs DIA projects
DIA is more isolated, was more ambitious
RTD has public engagement and more checks and balances, so more restricted
two problems
no agreed upon optimization function
maybe not needing to agree on the optimization, but understand the tradespace of tradeoffs
no agreed upon time horizon for calculating value
sociotechnical systems
Integration practices
How to change an organization
Talking about executives
CEO, CTO
Is the CTO role transferrable?
Sample of CTOs from LinkedIn
Average age: 48
48% MS or PhD
56% medium to small firms
Is CTO a glorified individual contributor or an owner of the engineering pipeline?
Models of CTO types
The Anchor
head of product development
The Coordinator
The Evangelist
a public persona
The Visionary
anticipates future change
more like a technical CEO?
The Strategist
Michael Cusumano on industry platforms
Basic Types
Transaction Platforms
App Store
Innovation Platforms
Intel CPU
AWS
Hybrid
lots are moving towards hybrid of the two
How much kindling does your platform need to get the fire started?
Trust Center for MIT Entrepreneurship calls this the Beachhead Market
Platforms
Spans multiple products
industry platform
sharing across firms
two sided market
product platform
sharing within the firm
often done for cost savings
though there does seem to benefits to scale: more worthy of investment the more internal scale
sounds like this includes internal frameworks in software
modularity, standardization, component reuse are possible synonyms, so sounds like Bruce agrees with this
BMW example
increased shared parts to save money to spend on building more models
presenting to the customer as a family of products doesn’t necessarily mean shared platform
passive vs active sharing
passive
someone reuses some existing work
this seems like kind of have network effects
active
looking around the firm to figure out who needs the shared component and what are everyone’s requirements
a thought
seems like lots of successful enterprise software comes from initially serving internal needs like this then beginning to sell them externally
classmate mentions that Google Cloud was like this
badge engineering
putting a logo on a product is enough to differentiate it, and change pricing
1983 GM cars in fortune magazine
commonality premium
extra cost to design a common component
this is the classic problem in code share
Lifecycle Costs
Tom Toner
Semiconductor machine
Mean Time Between Failures set as constraint
Cymer OnPulse
Sell a device but charge based on uptime
Data safety is sometimes a problem
Good margins for Cymer, customers liked the predictable pricing
Lifecycle Assessment
Started in the environmental movement to check environmental impact
Different time spans reflect different ROIs
SESAME model
Lifecycle Cost Analysis
Discussion on electric vehicles
https://www.theguardian.com/commentisfree/2023/jun/03/electric-vehicles-early-adopter-petrol-car-ev-environment-rowan-atkinson
Holistic approach requires thinking about transportation
public transportation more efficient in terms of space and energy
cost of maintaining roads
heavier
Afreen Siddiqi
On Optimization
in industry
Amazon, airlines, communication systems use critically use optimization models
“large scale” is between thousands and millions of variables
dodging local extrema to find the global extrema
linear vs non-linear problems
most interesting engineering problems are non-linear
simplex method
if you have a linear problem, the intersections of all your linear constraints is where the optimal solutions will exist
LP = linear programming, single objective
NLP = non linear programming, single objective
MOLP = multiple objective, linear programming
MONLP = multiple objective, non linear programming
Mean variance optimization
EM.413 meeting
Michael Trice
Communication and rhetoric for complex systems projects
The curse of knowledge
Elizabeth Newton study on tapping songs
Significant overestimate by information sharers
Rhetoric vs philosophy
Rhetoric is sharing of knowledge
Philosophy is seeking truth
Outcome optimizing is different than truth seeking
Aristotle
Kairos
The opportune moment to place a convincing argument
Bridging the knowledge gap
Cicero
Introduces Romans to Greek philosophy
Five canons of rhetoric
Invention
Arrangement
Style
Memory
Delivery
Where does one find the arguments?
My answers
Stakeholder needs analysis
Find the problem
Deduction
Non rhetoric
Data
Testimony
Laws
Maxims
Rhetoric
Reasoning
Appeals
Stasis
Attributed to Aristotle
Grows from the opposition of agitation and denial
Framework
Fact
Definition
Causation
Value
Policy
Heilmeier catechism
Modern form of stasis
A useful interrogation of any proposal
Nora Jackson
Presentation coaching
Questions for presentation for WRAP coach meeting testing the logic of your argument
What did the partner ask
Background research and company values
Motivated by urgent problem, opportunity, etc?
Narrative abstract with set of basic claims
Slide design
Edward Tufte
Written in data display
Highlight takeaway
Symbolic communication rather than verbal
Michael Alley
Pairing verbal with visual streams of information improves recall
Dual coding theory
Build your talk on messages, not topics
Memorize the messages but not the underlying talk
7-10 sentences for each slide
Focus on results not on what you did
Complexity
Complexity correlates with cost
Typical measures
parts count
source lines of code or function calls
information content
should actually be Technical Simplicity
Mentions the difference between Technical Simplicity vs Interfacial Simplicity
Dimensions of complexity in system development
Technical Simplicity
McCabe graph theoretic structure
Shannon Entropy
Gutman Graph Energy
structural
organizational
homomorphic forces between structural and organizational?
complex vs complicated
funny to hear both these brought up
I guess I would say complicated sounds like “someone added complexity, hence they complicated it”.
is there a difference between functional complexity and structural complexity?
We haven’t gotten this to a science yet
Complexity vs modularity as a tradespace
Topology
understand the role of System Architecture on overall complexity
Model based project design
Systems have
Elements
Relationships
Dynamics
Model types
Network
CPM
DSM
System dynamics
Agent based
Parametric
Models can handle different complexities better or worse
Detail complexity
Dynamic complexity
Different functors from reality to model chooses different granularities
If there was a good way to store category theory database we could use that as a backend with different front ends
Good projects should improve organizational capability
Do compounding work
How does individual and team effectiveness evolve?
Nonaka on knowledge cycle
SECI
Socialization
Externalization
Combination
Internalization
Moving between
Tacit knowledge
Explicit knowledge
Knowledge graph
Learning dynamics
Not much published data on this
Bruce Henderson
Boston consulting group
As experience doubles, efficiency improves around 20-30%
From 1936
Learning curve
Are there zero cost ways to transition tacit knowledge to explicit knowledge ?
Nonaka
Project Design for Diversity and Distribution
Why go global?
my thought
cost
access to larger talent pool
asynchronicity
some of the benefits are often false promises
Coordination
Coordination is the management of dependencies
Coordination has a distance
communciation efficiency
distribution and time zones
exception handling behavior
different priorities
misreading indicators
Coordination can be designed
Tacit abilities are an asset
If you can predict it, you can design it
Knowledge is testable prediction
Culture
Geert Hofstede dimensions of value in culture
Individualism
Masculinity
Uncertainty avoidance
Power distance
Long-term orientation
EM.413 System Architecture Bruce Cameron meeting
Summary of Bill Simmons presentation
Three rules of scalability
Use partition-able, parallelize-able methods
Reduce intra-process communication to an absolute minimum
kind of like Mythical man month
Amdahl’s Law
Look for opportunities for “sloppiness”
keep things slow where they can be slow
Use abstractions to increase achievable product complexity
Architecture as borrowed term from architecture
Ballerina vs gymnast
aesthetics can be part of the the function
Guidance for spring project
the narrative for our project
is automation useful, or the real problem?
if it is, where can we actually contribute?
implies things about potential over cost and over design
don’t take it as granted that modular is always better
Imagine the world as it could be
can imagine a big world
sell the product
Principles
Essential Complexity vs Apparent Complexity
like Technical Simplicity vs Interfacial Simplicity?
