The document discusses similarities between the urban planning of Paris by Georges-Eugène Haussmann in the 1850s and REST (Representational State Transfer) architectural style for distributed hypermedia systems defined by Roy Fielding in 2000. It notes how Haussmann redeveloped Paris to address issues like disease, congestion and security through principles like layered modular design and that his approach shares similarities with REST concepts like client-server architectures, statelessness, and uniform interfaces. It also discusses how aspects of developing cities and web services can be compared, such as continuous delivery of new infrastructure, use of microservices, and handling of everyday issues.

1. Eric Horesnyi | streamdata.io
Network-based Architectures
Fowler, Fielding, and Haussmann

2. The « Digital » gap
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3. Haussmann & Fielding
1853, Paris 2000, Irvine
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4. CHALLENGES
IN PARIS,1853
Haussmann Fielding and Fowler
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5. High Dropout
Cholera, 1832 – 19,000 dropout
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6. Congestion
1hab/sq mt density
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7. Slow & Unsecure
Security threats: No
inspection possible
obscure streets
No patches to remove
viruses and threats
lack of air circulation
Poor latency: slow
access lines
narrow streets
Street in Ile de La Cité
Early XIXth

8. Unstable system
Full reboot 1789, 1815,
1830, 1848…
No backward
compatibility
No service desk
Restricted vote
DDOS in small access
lines
Barricades
Liberty Leading the People, July 28th, 1830'
by Delacroix

9. INHERITED FEATURES
HTTP//PARIS 1789-1853
Haussmann Fielding Fowler
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10. Inherited Properties
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11. DNS
.gov, .com and .fr
follow same scheme
Seine is .root
Streets start there
Right/even
Left/Uneven
Paris street numbering, 1805

12. Famous heritage
Napoleon, France 1804 Tim Berners-Lee, CERN ‘90
Comment: // limited to ability to establish basic rules. I do not admire Napoleon for anything else.

13. Separation of concernsClient Server
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14. Stateless
All clients
are treated
equal, no
special
treatment,
no
segregation
Palais de Justice, Ile de la Cité

15. Stateless
Client access server via a network call

16. SELECTION OF PROPERTIES
FIELDING // HAUSSMANN
REST // PARIS
Haussmann Fielding Fowler
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17. Mission
Network performance
throughput, small
overhead, bandwidth
User-perceived
performance latency,
and completion
Network-efficiency
avoid using the street
too much.
Homeworking
Napoleon III describing his mission to
Haussmann, 1853

18. KPIs Haussmann // Fielding
Scalable make it possible for Paris to grow
Simple no need for a city-user manual,
Modifiable ability to evolve in the future through change
Extensible add new neighborhood
Customizable specialize a building without impacting others
Configurable easily modify a building post-deployment
Reusable building can host a bakery then a cremerie
Visible to provide best security and auditability
Portable style should work well in other regions
Reliable susceptible to failure (no single event could stop
water, gas or circulation for citizens)
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19. P1: Low-Entry Barrier
A popular neighborhood in Paris
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20. P2: Extensibility
Streaming = Paris Metro/Subway, 1900
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21. P3: Distributed Hypermedia
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22. P4: Anarchic Scalability
Paris Metropole today, 10m+ people
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23. P6: Independant Deployment
Ile de La Cité restructured, embedding legacy/sacred Notre
Dame
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24. WHY HAUSSMANN DECIDED
TO MAKE PARIS RESTFUL
Haussmann Fielding Fowler
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25. REST=LCODC$SS&UI
CSS=Client-Server-Stateless
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26. Layer 1: sewage & gas
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27. Layer 2: street & boulevards
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28. Layer 3: roofs
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29. Layered Networks
Within a layer, a
component connects to
its neighboor
Between two layers,
gateways allow for
interaction
Each layer is
autonomous
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30. Cache
700 concurrent clients
80,000 in cache
2m records
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St Geneviève Library, 1850

31. Cache
Opera, a server with cache
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32. Code On Demand
Les Halles, setting the tone for all restaurants in the City
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33. Uniform Interface = Genious
Codified UI, by floor (header), with token/key, proxy, cache
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34. Uniformity = beauty inside
Uniformity in APIs brings harmony in UX
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35. Uniformity = pattern beauty
Uniformity brings fractal harmony: still there from a distance
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36. HAUSSMANN // FOWLER AS
URBANISTS
Continuous Delivery & Microservices
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37. Continuous Delivery
Resilient Water Induction, requiring aqueducts and
reservoirs
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38. Continuous Delivery
Aqueduct, Arcueil Reservoir, Arcueil
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39. Microservices
Not too big
Autonomous
components
Own API
Standard protocol
Scalable
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40. Zoning
Quartier Panthéon, a zone dedicated to “The Big Men”

41. Lead by example
Opera, an Hypermedia API > great UX
>>> traction for API owners

42. Cut Corners
Haussmann corners: Most difficult piece & beautiful

43. PolyglotXVIII architecture encapsulated, if API
complies
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44. PARIS 160 YEARS LATER
HTTP REST 16 YEARS LATER
Sustainable systems?
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45. UX performance
City of Lights: 20m unique visitors a year

46. Reproductible
Chicago after the Burnham Plan, designed in 1909

47. Durable
Courneuve, 1986, 20y lifespan Monolith

48. Evolvable
Tour Eiffel under construction, evolution built years after
Haussmann had left office

49. DAYTODAY LIFE IN A
RESTFUL CITY
Haussmann Fielding Fowler
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50. Incomplete Protocol: Velib
Leverage reusable
assets
Share same layer as
existing traffic
But incomplete
protocol: collisions,
missing RFC for cars
Rate-limited API,
realtime difficult
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51. Error Handling in your code
Gare Montparnasse, 1895 –HTTP or REST does not
prevent from good error handling, contrib @rit

52. HTTP//PARIS
DICTIONARY, MAPS & RESSOURCES
Haussmann Fielding Fowler
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53. Glossary
Code Civil HTTP
Paris Web
Boulevards Internet Backbone
Streets Access Lines
Street Numbers URI
Light in the streets Authentication
Concierge Proxy
Library Cache
Carriage Request/Response
Subway/Metro Streaming
Homeworking Diff update// JSON Patch
Pierre de Carrière JSON
Compagnon du Devoir API Developer
Haussmann Architect
Beaux Arts JS Developers
Façade API
Haussmann Façade RESTful API
Utilities Cloud/PaaS
Annonces Parisiennes Criteo
Grands Magasins Amazon
Opera Deezer
Theaters Netflix
Prefecture NSA
Bibliotheque Nat. Wiki
Senat W3C
Assemblee Nationale IETF
Louvre Pinterest
Bois de Boulogne MineCraft
Bois de Vincennes Facebook
Bon Marché Ebay
Eiffel Tower Twitter
Latin Quarter Udacity, Coursera
Left bank spirit Android
Right bank spirit Apple iPhone
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54. Resources
Paris Architecture & Urbanism: Musée Carnavalet, Cité Chaillot
Haussmann:
Haussmann à Paris : Architecture et urbanisme Seconde moitié du
XIXe siècle, Book, 2012
HTTP: Tim Berners-Lee & Team, Cern, 1990
REST: Network-Based Architecture Style, Thesis, Fielding 2000
Continuous Delivery : Farley & Humbl, 2010
Microservices :
Microservices in a Nutshell, Fowler & Lewis, Thoughtworks, 2014
Web Corp Organization: How Google Works, Eric Schmidt, 2014
Design & UX : Jonathan Ive, Apple by The New Yorker, 2015
Microservices Building Microservices, Sam Newman, O’Reilly Book,
2015