Learning HTTP/2

More documents

Recommendations

Info

[ 0.346] recv DATA frame [ 0.346] recv DATA frame [ 0.346] recv DATA frame [ 0.348] recv DATA frame [ 0.348] recv DATA frame [ 0.348] send WINDOW_UPDATE frame Here we get the data for the stream. You see five DATA frame come down followed by a WINDOW_UPDATE frame. The client is indicating to the server that it has consumed 10915 bytes of the data frames and is ready for more data. Note that this stream is not done yet. But the client has work to do and thanks to multiplexing it can get to it. [ 0.348] send HEADERS frame :path: /styles/screen.1462424759000.css [ 0.348] send HEADERS frame :path: /styles/fonts--full.css [ 0.348] send HEADERS frame :path: /images/favicons/favicon.ico?v=XBBK2PxW74 Now that the client has some of the base HTML, is can start asking for objects on the page. Here you see three new streams created, ids 15, 17, and 19 for stylesheet files and a favicon. (Frames were skipped and abbreviated for clarity). [ 0.378] recv DATA frame [ 0.378] recv DATA frame [ 0.378] recv DATA frame [ 0.378] send WINDOW_UPDATE frame (window_size_increment=12216) [ 0.379] recv HEADERS frame [ 0.379] recv DATA frame [ 0.379] recv DATA frame ; END_STREAM [ 0.380] recv DATA frame [ 0.380] recv DATA frame [ 0.385] recv HEADERS frame [ 0.387] recv DATA frame [ 0.387] recv DATA frame ; END_STREAM [ 0.389] recv HEADERS frame [ 0.390] recv DATA frame [ 0.390] recv DATA frame [ 0.390] send WINDOW_UPDATE frame (window_size_increment=36114) [ 0.390] send WINDOW_UPDATE frame (window_size_increment=11098) [ 0.410] recv DATA frame [ 0.410] recv DATA frame [ 0.410] recv DATA frame [ 0.410] recv DATA frame [ 0.410] recv DATA frame 44 | Chapter 3: The Protocol
Here we see the overlapping streams coming down. You can see the HEADERS frames for streams 15, 17, and 19. You see the rest of the data for stream 1. You see the various window updates including a connection level update for stream 0. [ 0.457] send GOAWAY frame (last_stream_id=0, error_code=NO_ERROR(0x00), opaque_data(0)=[]) Finally we get the GOAWAY frame. Ironically this is the polite way to tear down the connection. The flow may seem cryptic at first, but walk through it a few times. Everything logically follows the spec and has a specific purpose. In this straightforward example you can see many of the elements that make up <strong>HTTP</strong>/2 including flow control, multiplexing and connection settings. Try the nghttp tool yourself against a few h2 enabled sites and see if you can follow those flows as well. Once it starts to make sense you will be well on your way to understanding the protocol. On the Wire | 45
Page 3 and 4: Learning HTTP/2 An Introduction to
Page 5 and 6: Table of Contents 1. Evolution of H
Page 7: Nginx 80 Squid 81 Varnish 81 Apache
Page 10 and 11: Nelson wanted to create a “docuve
Page 12 and 13: RFC 2068, then later replaced by RF
Page 15 and 16: CHAPTER 2 Existing workarounds to i
Page 17 and 18: It is then critical to ensure that
Page 19 and 20: Cache at the Edge (= on a CDN) Cach
Page 21 and 22: 1. Revisit their usage periodically
Page 23 and 24: Figure 4.6 - Average RWD bytes serv
Page 25: the HTTP/1.1 standard. They will ha
Page 28 and 29: • Header Compression: As if a bin
Page 30 and 31: Frames As mentioned before, HTTP/2
Page 32 and 33: Length = the first three bytes Read
Page 34 and 35: Figure 3-2. GET Request Message and
Page 36 and 37: Flow Control A new feature in h2 is
Page 38 and 39: In this tree, the client is communi
Page 40 and 41: Choosing What to Push Depending on
Page 42 and 43: accept: text/html,application/xhtml
Page 44 and 45: Example 3-2. HTTP/2 GET Response (
Page 49 and 50: CHAPTER 4 HTTP/2 Implementations Ja
Page 51 and 52: • Performance optimizations (DNS
Page 53 and 54: 1. Type chrome://net-internals on C
Page 55 and 56: — HTTP2_SESSION_GOAWAY (used to i
Page 57 and 58: --> priority = 0 --> stream_id = 1
Page 59 and 60: ... --> fin = true --> has_priority
Page 61 and 62: ... --> parent_stream_id = 0 --> st
Page 63 and 64: We are going to highlight a few por
Page 65 and 66: content-type: text/css --> stream_i
Page 67 and 68: We should see something like this:
Page 69 and 70: Figure 6.1.1j - Server-Push Timelin
Page 71 and 72: HTTP/2 support (and how to disable
Page 73 and 74: — 1: important; intended to alway
Page 75 and 76: Firefox Dependencies and Priorities
Page 77 and 78: According to the Netcraft’s Web S
Page 79 and 80: The example below shows the HTTP He
Page 81 and 82: • http2_recv_buffer_size: Sets th
Page 83 and 84: Squid Squid (also known as squid-ca
Page 85 and 86: Akamai customers are able to self-c
Page 87: Figure 6.4e - Fastly logo Fastly an

Learning HTTP/2

Create successful ePaper yourself

Delete template?

Save as template?