This document discusses websockets and web workers for building low latency interactive web applications. It covers the problems with traditional techniques like polling and describes how websockets enable full-duplex communication in a scalable way without overhead. Web workers allow running JavaScript in a non-blocking way by using multiple threads to improve performance of computationally intensive tasks.

2. WEBSOCKETS AND WEBWORKERS
FOR LOW LATENCY INTERACTIVE WEB APPLICATIONS

3. WEBSOCKETS

4. AGENDA
lInteractive Web Applications
lProblems
lEarlier Techniques
lPolling
lLong Polling
lStreaming
lHTML5 Web Sockets
lHow Web Sockets work
lComparison of Polling vs Web Socket
lSupport Chart
lEvent Looping in JavaScript
lNon Blocking Threads
lWeb Workers

5. INTERACTIVE WEB APPLICATIONS

6. PROBLEMS
lLow latency
lTime
lCost
lContinuos data traffic
l1 way communication

7. EARLIER TECHNIQUES
lPolling
lLong Polling
lStreaming

8. POLLING

9. LONG POLLING

10. STREAMING

11. HTML5 WEBSOCKETS
lFull Duplex Bidirectional Communication
lScalable
lReal Time
lNo Overhead
lReduced Complexity
lUpgrades to the WebSocket Protocol

12. HOW IT WORKS

13. WEBSOCKETS SYNTAX
lvar Socket = new WebSocket(url, [protocal] );
lATTRIBUTES
lSocket.readyState
lSocket.bufferedAmount
EVENTS
lOpen
lMessage
lError
lClose
METHODS
lSocket.send()
lSocket.close()

14. POLLING vs WEBSOCKETS
Use case A: 1,000 clients polling every second:
Network throughput is (871 x 1,000) = 871,000 bytes = 6,968,000 bits per second (6.6 Mbps)
Use case B: 10,000 clients polling every second:
Network throughput is (871 x 10,000) = 8,710,000 bytes = 69,680,000 bits per second (66 Mbps)
Use case C: 100,000 clients polling every 1 second:
Network throughput is (871 x 100,000) = 87,100,000 bytes = 696,800,000 bits per second (665
Mbps)
Use case A: 1,000 clients receive 1 message per second:
Network throughput is (2 x 1,000) = 2,000 bytes = 16,000 bits per second (0.015 Mbps)
Use case B: 10,000 clients receive 1 message per second:
Network throughput is (2 x 10,000) = 20,000 bytes = 160,000 bits per second (0.153 Mbps)
Use case C: 100,000 clients receive 1 message per second:
Network throughput is (2 x 100,000) = 200,000 bytes = 1,600,000 bits per second (1.526 Mbps)

15. POLLING vs WEBSOCKETS

16. SUPPORT CHART

17. DEMO

18. WEBWORKERS

19. EVENT LOOPING IN JAVASCRIPT

20. NON BLOCKING THREADS

21. WEB WORKERS

22. DEMO

23. QUESTIONS

24. THANK YOU