HTTP/2: Ease the Transition, Remove Implementation Barriers. Robert Haynes Ronnie Dockery

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2 HTTP/2: Ease the Transition, Remove Implementation Barriers Robert Haynes Ronnie Dockery

3 No One Likes Slow 3

4 No One Likes Slow 74% of users will leave a slow website after just 5 seconds or less 3

5 No One Likes Slow 74% of users will leave a slow website after just 5 seconds or less Slow application: Reduced productivity 3

6 No One Likes Slow 74% of users will leave a slow website after just 5 seconds or less Slow application: Reduced productivity Every 100 millisecond delay costs Amazon1% in sales 3

7 Things Are Not Getting Easier 4

8 Things Are Not Getting Easier Mobile devices now account for 35% of global Internet traffic

9 Things Are Not Getting Easier Mobile devices now account for % of global Internet traffic The average web page has grown since MB Growing exponentially 4

10 Things Are Not Getting Easier Mobile devices now account for % of global Internet traffic The average web page has grown since MB Growing exponentially Radio = Latency Fiber Cable LTE 34% mostly use mobile Internet 4

11 Addressing Performance Challenges F5 survey shows growth in plans to deploy performance-related services COMPRESSION 12% 21% ACCELERATION 12% 25% SSL OFFLOAD 9% 21% CACHING 9% 19% 5

12 HTTP Timeline 1996 HTTP/1.0 Static content Small objects Low number of objects 6

13 What Were the Issues with HTTP/1? 1 request = 1 connection Connection setup is expensive Inefficient when large numbers of objects on page Mitigated in part with keep-alive 7

14 What Were the Issues with HTTP/1? No virtual host support Each site needs one IP address Inefficient use of addresses Multi-homing server limits (255 per server on Linux < 2.2 kernel) 8

15 What Were the Issues with HTTP/1? Primitive caching Cache invalidation used absolute times Clock skew caused problems Not explicit enough 9

16 HTTP Timeline HTTP/1.0 HTTP/1.1 Dynamic content Bigger objects More objects 10

17 1996: HTTP/1.1 CACHING PERSISTENT CONNECTIONS VIRTUAL HOSTS Cache-control header Max-age directive Etag header Default = all connections No keepalive messages Servers still have timeouts Host header now required Multiple sites one IP address 11

18 What Are the Issues with HTTP/1.1? Requests are blocking One connection can only process one request at a time Slow object blocks others downloading Solution multiple connections 12

19 What Are the Issues with HTTP/1.1? Workarounds can be counter productive Multi-origin websites cause clients to open up to 30 TCP connections.css /images/ HTML 13

20 What Are the Issues with HTTP/1.1? Not that efficient Headers not compressed Header numbers and size increasing meowmewomeowmeowmeowm eowmeowmeowmeomeowmew omeowmeowmeowmeowmeow meowmeomeowmewomeowme owmeowmeowmeowmeowmeo Meowmewomeowmeowmeowm eowmeowmeowmeomeowmew omeowmeowmeowmeowmeow meowmeomeowmewmeowmew omeowmeowmeowmeowmeow meowmeomeowmewomeowme owmeowmeowmeowmeowmeo meowmewomeowmeowmeowm eowmeowmeowmeomeowmew omeowmeowmeowmeowmeow meowmeomeowmewomeowme owmeowmeowmeowmeowmeo Meowmewomeowmeowmeowm eowmeowmeowmewoofmeow Header Data 14

21 HTTP Timeline HTTP/1.0 HTTP/1.1 YouTube Hey Nice Cat! His name is Mittens. Video content User-generated content 15

22 HTTP Timeline HTTP/1.0 HTTP/1.1 YouTube SPDY More objects Bigger objects Mobile devices 16

23 2009: SPDY Multiplexed Requests Compressed Headers Requires TLS Concurrent requests Single connection (More on this later) Reduced header overhead Smaller page size Enforced SSL security (Whether you want it or not) 17

24 What Are the Issues with SPDY? Not a standard Forced secure connections (TLS) Maybe not as SPDY? (depending on who you listen to) Insecure compression 18

25 HTTP/2 Timeline HTTP/1.0 HTTP/1.1 YouTube SPDY HTTP/2 RFC 7540 May

26 2015: HTTP/2 Is Here! Multi-plexed requests "Safe" compression TLS optional* Stronger cryptography * Not in practice 20

27 2015: HTTP/2 Is Here! Multi-plexed requests "Safe" compression TLS optional* Stronger cryptography * Not in practice 20

28 HTTP/2 Adoption Data from 21

29 HTTP/2 Adoption 7.8% of sites Most webmonsters Data from 22

30 HTTP/2 Quick Overview

31 3 Shocking Facts About HTTP/2 Everyone Should Know It s binary It uses multi-plexed requests on a single connection It uses compressed headers 24

32 3 Shocking Facts About HTTP/2 Everyone Should Know b It uses multi-plexed requests on a single connection It uses compressed headers 24

33 3 Shocking Facts About HTTP/2 Everyone Should Know b It uses compressed headers 24

34 3 Shocking Facts About HTTP/2 Everyone Should Know b Itusescompressedheaders 24

35 Multi-plexed Requests A major contributor to improved HTTP/2 performance 25

36 Multi-plexed Requests A major contributor to improved HTTP/2 performance Multiple outstanding requests per connection Uses a construct known as "streams" Max number of streams is configurable BIG-IP default is typically 10 probably too low 25

37 HTTP/1.1 26

38 HTTP/1.1 Hello Hello May I have a picture of a cat please? Here is a cat May I also have a picture of a dog? Here is a dog May I also have a picture of a turtle? Thanks, bye Here is a turtle Bye 26

39 HTTP/1.1 HTTP/2 Hello Hello May I have a picture of a cat please? Here is a cat May I also have a picture of a dog? Here is a dog May I also have a picture of a turtle? Thanks, bye Here is a turtle Bye Hello Hello May I have a picture of a cat please? And another cat? And a dog? Here is a cat And a dog May I also have a picture of a turtle? Thanks, bye Here is another cat And a turtle Bye 26

40 Compression for Headers Request 1 Request 2 Method scheme GET HTTPS Most headers are the same between requests Method scheme GET HTTPS host path Accept user-agent F5.com /resource image/jpeg Mozilla/5.0 Why send them every time? Just keep a header table on each side of the connection host path accept user-agent F5.com /images image/jpeg Mozilla/5.0 Stream 1 headers method: Get scheme: HTTPS host: f5.com path: /resource accept: image/jpg user-agent: Mozilla/. Update only what has changed in each stream Stream 2 headers Method: Get Scheme: HTTPS Host: f5.com path: /images Accept: image/jpg User-agent: Mozilla/. 27

41 HTTP/ images 100 milliseconds (added) latency Served from Microsoft Azure One hundred requests: HTTP/1: Browser limited to six simultaneous requests Page load 18 seconds 28

42 HTTP/2 100 images 100 milliseconds (added) latency Served from Microsoft Azure One hundred requests: HTTP/2: Browser can request more than six simultaneous requests Page load 5 seconds 29

43 Stronger Cryptography Ephemeral keys only (forward secrecy) 30

44 Stronger Cryptography Ephemeral keys only (forward secrecy) TLS 1.2 or newer required for HTTP/2 Minimal key sizes 128 bit EC, 2048 bit RSA 30

45 TLS Is Not Mandatory. But It Is Really. 31

46 So, Why Isn t the Web All HTTP/2 Yet?

47 Potential Barriers that Slow Adoption of HTTP/2 Low availability of HTTP/2 services 41% Lack of familiarity with the technology Lack of backward compatibility with HTTP/1.x Lack of back-end support Incompatibility with current security infrastructure 31% 31% 29% 28% The requirement that all application traffic be secured via TLS/SSL 19% 33

48 Potential Barriers that Slow Adoption of HTTP/2 Low availability of HTTP/2 services 41% Lack of familiarity with the technology Lack of backward compatibility with HTTP/1.x Lack of back-end support Incompatibility with current security infrastructure 31% 31% 29% 28% The requirement that all application traffic be secured via TLS/SSL 19% Source: IDG Enterprise Research 33

49 HTTP/2 Impacts the Infrastructure Optimization HTTP/2 HTTP/ Client Server Security Reporting 34

50 So? Inspection Optimization Protocol Understanding Reporting 35

51 So? Inspection Optimization Reporting 35

52 So? Inspection Optimization Reporting 35

53 HTTP/2 Made Easy

54 HTTP/2 Gateway Reporting Optimization Security HTTP/2 HTTP/1.x Protocol Gateway GET /images/cat.jpg Client Server ADC HTTP/2 Performance Full ADC Services HTTP/ 1Simplicity 37

55 Multi-Protocol Gateway HTTP/1.x HTTP/1.1 SPDY HTTP/2 GET /images/cat.jpg Protocol Gateway GET /images/cat.jpg Client HTTP/1.1 GET /images/cat.jpg Server ADC 38

56 Two Steps to Implement HTTP/2 Gateway Copy HTTP/2 Profile Add Profile to Virtual Server 39

57 Two Steps to Implement HTTP/2 Gateway Copy HTTP/2 Profile Add Profile to Virtual Server That s it... really! 39

58 HTTP/2 Profile Settings Things you might want to play with (then TEST): Concurrent streams per connection: Increase to 30 or more Inserting a header if HTTP/2 is used track on your webserver 40

59 From Slow HTTP/1.1 41

60 To Fast(er) HTTP/2 HTTP/1.1 bottleneck removed! 42

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63 As with all performance optimization processes, the moment you remove one performance bottleneck, you unlock the next one. In the case of HTTP/2, TCP may be it. Which is why, once again, a well-tuned TCP stack on the server is such a critical optimization criteria for HTTP/2. High Performance Browser Networking, Ilya Grigorik, O Reilly Media 44

64 We re Only Moving the Bottleneck TCP

65 TCP Inefficiencies: the Next Bottleneck Things to consider: Congestion control algorithms Window sizing Multi-path TCP High RTT and packet loss links (radio) 46

66 Perhaps You Need a TCP Optimizer? RTT = 100 ms TCP algorithm = Woodside TCP window scale = 65,535 KB RTT = 1 ms TCP algorithm = High speed TCP window scale = 1 MB Know any good ones? 47

67 Summary Impact Performance Opportunities Binary protocol TCP optimizations required SSL offload essential Significant performance improvements Reduced header overhead Smaller page size Fully multi-plexed connections Server push possibilities Leverage existing ADC 48

68 Give Feedback Get Points! Add class to your personal schedule. Survey will pop up in Mobile App. Answer the multiple choice. Submit your question to complete. Receive 5 points!

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