Thesis Presentation: Web-Integrated Smart City Infrastructure
Upcoming SlideShare
Loading in...5
×

Like this? Share it with your network

Share

Thesis Presentation: Web-Integrated Smart City Infrastructure

  • 1,805 views
Uploaded on

Thesis Presentation - Politecnico di Torino ...

Thesis Presentation - Politecnico di Torino
26/11/2012

A caching proxy for hybrid CoAP-HTTP networks.

More in: Technology
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
No Downloads

Views

Total Views
1,805
On Slideshare
1,794
From Embeds
11
Number of Embeds
4

Actions

Shares
Downloads
79
Comments
0
Likes
1

Embeds 11

http://www.linkedin.com 8
http://www.docseek.net 1
http://www.slashdocs.com 1
http://www.docshut.com 1

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide

Transcript

  • 1. Web-IntegratedSmart City InfrastructureA caching proxy for hybrid CoAP-HTTP networks.Supervisor: Candidate:Prof. Dr. Giovanni Malnati Francesco CorazzaCo-supervisors:Prof. Dr. Stefano Ceri (Politecnico di Milano)Prof. Dr. Friedemann Mattern (ETH Zürich)Tutor:Dipl.-Ing. Matthias Kovatch (ETH Zürich) 26 November 2012
  • 2. Web-Integrated Smart City Infrastructure Francesco CorazzaSmart Cities? Ningbo City, China Taipei , Taiwan 2
  • 3. Web-Integrated Smart City Infrastructure Francesco Corazza •1. Smart Cities and Internet: • • interconnected worlds • •• Wireless Sensor Network (WSN) The Internet of Things vision • Spatially distributed autonomous sensors Internet of Things • Low bandwidth, lossy, unstable medium (Trillions of nodes) • Low energy, power, processing, faults • IEEEE 802.15.4 – Low Rate WPAN Fringe Internet• Internet of Things (Billions of nodes) • Proprietary solutions Core Internet • IPv6 over Low-power WPAN (6LoWPAN) (Millions of nodes)• IP as common language • “Things” can access standard web services • “Things“ can be addressed from Internet • Application-layer interconnection (Web) 5
  • 4. Web-Integrated Smart City Infrastructure Francesco Corazza •1. Smart Cities and Internet: • • RESTfy real world • •• Web of Things • Web tools in real world (browser, search) Intersection originating the WoT • Physical/virtual mashups• REST • Everything is a resource • Architectural constraints • Scalability, usability, and accessibility • HTTP• Constrained Application Protocol • Designed from a subset of HTTP • Low overhead (UDP fragmentation) • Machine to Machine (M2M) applications 7
  • 5. Web-Integrated Smart City Infrastructure Francesco Corazza •1. Smart Cities and Internet: • • CoAP (Constrained Application Protocol) • •• Features • Async communication (request/response) HTTP vs. CoAP protocol stack • Stateless reliability (confirmable/ack) 7 HTTP CoAP • Security (CoAPS) • Observation (native publish/subscribe) 4 TCP UDP • Blockwise transfers (stateless large transfers) IPv6• Options 3 IP 6LoWPAN • Minimum parsing complexity • Finite number of identifiers 2 Ethernet MAC 802.15.4.5 MAC• Caching 1 Ethernet PHY 802.15.4.5 PHY • Freshness model • Validation model• Proxying 9
  • 6. Web-Integrated Smart City Infrastructure Francesco Corazza •2. Web-Integration: • • proxy deployment • • Forward proxy• Positioning • Server-side • Client-side • External Reverse proxy• Server-side proxy ✓ Effective TCP/UDP mapping ✓ Caching ✓ Multicast ✓ Traffic queuing and limiting ✗ Scalability ✗ Availability Intercepting proxy• Uri-mapping • Homogeneous (intercepting proxy) • Embedded (reverse proxy) 11
  • 7. Web-Integrated Smart City Infrastructure Francesco Corazza •2. Web-Integration: • • cross-protocol mappings (HTTP to CoAP)• Reverse proxy HTTP Request GET http://proxy.mywsn.com/coap/cnb.mywsn.com/b/temp Accept: application/json• Embedded uri-mapping Constrained Network Proxy coap://proxy.mywsn.com Building CNB HTTP Client http://proxy.mywsn.com http://httpnode.example.com 2001:620:8:35db::1f Room A 170.1.52.200 2001:620:8:35C1::xxx 5683 Room B 80 Border Router CoAP Server Internet 2001:620:8:101f::1 coap://cnb.mywsn.com/b/temp 2001:620:8:101f::64 13
  • 8. Web-Integrated Smart City Infrastructure Francesco Corazza •2. Web-Integration: • • cross-protocol mappings (HTTP to CoAP) CoAP Request• HTTP-CoAP mapping Type: CONFIRMABLE - Uri-host: cnb.myswn.com • Split HTTP request uri Code: GET - Uri-port: 5683 Options: - Uri-path: b • Map Accept header - Accept: 50 - Uri-path: temp Constrained Network Proxy coap://proxy.mywsn.com Building CNB HTTP Client http://proxy.mywsn.com http://httpnode.example.com 2001:620:8:35db::1f Room A 170.1.52.200 2001:620:8:35C1::xxx 5683 Room B 80 Border Router CoAP Server Internet 2001:620:8:101f::1 coap://cnb.mywsn.com/b/temp 2001:620:8:101f::64 14
  • 9. Web-Integrated Smart City Infrastructure Francesco Corazza •2. Web-Integration: • • cross-protocol mappings (HTTP to CoAP) CoAP Response• Piggybacked response Type: ACKNOWLEDGE Options: Code: 2.05 - Content-Type: 50• Mag-Age Payload: {temp: 21.5} - Mag-Age: 60 Constrained Network Proxy coap://proxy.mywsn.com Building CNB HTTP Client http://proxy.mywsn.com http://httpnode.example.com 2001:620:8:35db::1f Room A 170.1.52.200 2001:620:8:35C1::xxx 5683 Room B 80 Border Router CoAP Server Internet 2001:620:8:101f::1 coap://cnb.mywsn.com/b/temp 2001:620:8:101f::64 15
  • 10. Web-Integrated Smart City Infrastructure Francesco Corazza •2. Web-Integration: • • cross-protocol mappings (HTTP to CoAP) Http Response• CoAP-HTTP mapping Status-Code: 200 OK • Cache-Control Cache-Control: max-age=60 Content-Type: application/json; charset=utf-8 • Content-Type Body: {temp: 21.5} Constrained Network Proxy coap://proxy.mywsn.com Building CNB HTTP Client http://proxy.mywsn.com http://httpnode.example.com 2001:620:8:35db::1f Room A 170.1.52.200 2001:620:8:35C1::xxx 5683 Room B 80 Border Router CoAP Server Internet 2001:620:8:101f::1 coap://cnb.mywsn.com/b/temp 2001:620:8:101f::64 16
  • 11. Web-Integrated Smart City Infrastructure Francesco Corazza •2. Web-Integration: • • caching • •• Response code (≠ HTTP) • 2.05, cache • 2.03, update • 2.0x, invalidate• Update max-age • Time passed in cache • max_age = original_max_age - cache_age 19
  • 12. Web-Integrated Smart City Infrastructure Francesco Corazza •3. Design the proxy: • • components • •• Californium • Rapid prototyping in backend • Layered architecture• Apache HttpCore • Minimal memory footprint • Non-blocking I/O• Apache HttpClient • Uses HttpCore internally • 1xx & 3xx codes managed • Built-in security• Google Guava Cache • Used in production by Google • 286.000 tests 22
  • 13. Web-Integrated Smart City Infrastructure Francesco Corazza •3. Design the proxy: • • integration (Californium architecture) • •• Layered architecture Resources • Chain of Responsibility Resource • Single thread model • Limited to clients and servers Endpoint• Pitfalls • Synchronized responses Abstractions • Blocking UDP thread Communicator • Missing client abstraction • Missing server abstraction TransferLayer Variable Layers Layers ⟳ UDPLayer 23
  • 14. Web-Integrated Smart City Infrastructure Francesco Corazza •3. Design the proxy: • • integration (proxying) • •• Encapsulations Resources • Forwarding resources (client) Resource • Stacks (servers)• Multi-thread model CoAP Resource HTTP Resource • Concurrent responses • Resource thread-safeness ⟳⟳⟳ Proxy Endpoint • Non-blocking UDP thread• Communicator Abstractions • Two message flows • Thread-safeness Proxy Communicator• Endpoint • Avoid HTTP in CoAP servers ⟳⟳⟳ HTTP Stack CoAP Stack ⟳ • Encapsulate cache Servers 25
  • 15. Web-Integrated Smart City Infrastructure Francesco Corazza • 3. Design the proxy: • • final architectureResources HTTP Client HTTP Translator CoAP Client Resource CacheAbstractions Proxy Endpoint Proxy Communicator HTTP Translator CoAP Stack HTTP StackServers 26
  • 16. Web-Integrated Smart City Infrastructure Francesco Corazza •4. Evaluation: • • performance assessment • • 400 100 requests/s Average Round Trip Time (ms)• Emulation 350 200 requests/s • Proxy JVM limitation 400 requests/s • CoAP Server Virtualization 300 600 requests/s• Test client 250 • Pre-compiled requests • Random distribution of requests 200 • Normal distribution of resources 150 • Average of several “runs”• Produced data 100 • Raw RTT distributions 50 • RTT/throughput trends • CDF for RTT 0 0 200 400 600 800 1000 Request number 27
  • 17. Web-Integrated Smart City Infrastructure Francesco Corazza • 4. Evaluation: • • performance assessment (CoAP-to-HTTP proxying) 350 Tests w/o cachingAverage RTT (ms) 300 250 Tests w/ caching 200 150 100 50 0 0 50 100 150 200 250 300 350 400 450 Produced throughput (Kbit/s) 1Cumulative Density F. 0.8 0.6 0.4 100 Kbit/s w/ cache 400 Kbit/s w/ cache 0.2 100 Kbit/s w/o cache 400 Kbit/s w/o cache 0 0 100 200 300 400 500 600 Average Round Trip Time (ms) 28
  • 18. Web-Integrated Smart City Infrastructure Francesco Corazza •4. Evaluation: • • hybrid mashup • • Paraimpu control Panel HTTP to CoAP Twits containing temperatures 33
  • 19. Web-Integrated Smart City Infrastructure Francesco Corazza • •Conclusions • • • CoAP draft evolution• Smart city 7 • Mashup as leading paradigm in the WoT K Lines added • Scalability through physical locality 6 K Unchanged Lines • Chains of proxies• Lesson learnt 5 • Design for extensibility • Interoperability through standards 4 • Cheat sheet for overlapping specifications 3• Future work • Standardization process 2 • Intercepting proxy • Secure proxy (HTTPS-CoAPS mapping) 1 0 35
  • 20. Web-Integrated Smart City Infrastructure Francesco CorazzaThank you for the attention 36