HTTP 2.0 and QUIC - Protocols of the (near) future

HTTP 1.1 forced both developers and browser vendors to invent different tricks in order to make sites to load and run faster. HTTP 2.0 and QUIC will provide many significant improvements overt HTTP 1.1.

In this talk I will give an introduction to both protocols and emphasize why are they so important for the Web development workflow and performance.

Transcript

1. HTTP 2.0 and QUIC
   protocols of the (near)
   future
   @ipeychev
   

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2. Why a new version of
   HTTP protocol?
   2.0
   

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3. HTTP is used by the World-Wide Web since 1990
   Browser sends request to the server
   Server responds
   GET /index.html HTTP/1.1
   HTTP/1.1 200 OK
   

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4. The number of requests per page increases
   HTTP Archive
   Top 100 sites
   data for
   15.11.2010 - 1.10.2014
   

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5. HTTP 1.1 has issues
   

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6. Optional parts, like
   HTTP Pipelining
   It is very latency
   sensitive
   The specification
   is huge
   HTTP 1.1 issues
   and more...
   

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7. Latency kills and bandwidth is
   not everything
   

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8. Latency vs bandwidth
   Ilya Grigorik
   Developer Advocate, Google
   

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9. What could be the solution?
   

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10. HTTP pipelining?
    WikipediA
    The free Encyclopedia
    

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11. HTTP pipelining
    

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12. Why not HTTP Pipelining?
    The server must send its responses in the same order that
    requests were received
    So the entire connection remains first-in-first-out (FIFO)
    and Head-of-line (HOL) blocking can occur
    and more, like buggy proxy servers
    

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13. In most browsers HTTP pipelining is disabled
    Or not implemented at all
    Browsers achieve multiplexing by opening multiple connections
    to servers
    As a result...
    

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14. Developer workarounds
    

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15. Image sprites
    1
    Sharding
    2
    Resource inlining
    3
    Developers invented workarounds
    

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16. Concatenating files
    4
    Combo services
    5
    Preloading resources
    6
    Developers invented workarounds
    

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17. Reducing cookie size
    7
    Using cookie-free domains
    8
    Using instead of @import
    9
    Developers invented workarounds
    

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18. Pack components into a multipart document

    (like email with attachments)
    10
    Developers invented workarounds
    

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19. browser diet
    

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21. Got tired?
    

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22. Welcome to
    HTTP 2.0 and QUIC
    

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23. HTTP 2.0 (draft 14)
    

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24. HTTP 2.0 fixes issues in HTTP 1.1
    without breaking the web
    

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25. Using
    HTTP Upgrade
    mechanism
    HTTP
    How browser switches to HTTP 2.0
    GET / HTTP/1.1
    Host: server.example.com
    Connection: Upgrade, HTTP2-Settings
    Upgrade: h2c
    HTTP2-Settings:
    

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26. HTTPS
    How browser switches to HTTP 2.0
    ALPN
    Using
    Application Layer
    Protocol Negotiation
    extension
    

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27. HTTP 2.0 features
    

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28. HTTP 2.0 Features
    It is a binary protocol, not text one
    Browser and server exchange frames
    Each frame belongs to stream
    Streams are multiplexed, with priorities
    Server push
    

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29. ONE connection to the server should be enough
    (not six connections per domain as most browsers do now)
    HTTP 2.0 Features
    

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30. Frames
    

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31. Frame format
    0 1 2 3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    | Length (24) |
    +---------------+---------------+---------------+
    | Type (8) | Flags (8) |
    +-+-+-----------+---------------+-------------------------------+
    |R| Stream Identifier (31) |
    +=+=============================================================+
    | Frame Payload (0...) ...
    +---------------------------------------------------------------+
    

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32. Frame types
    DATA Convey arbitrary data associated with a stream
    HEADERS Used to open a stream and carries name-value pairs
    PRIORITY Specifies the sender-advised priority of a stream
    RST_STREAM Allows abnormal termination of a stream
    SETTINGS
    Conveys configuration parameters that affect how endpoints
    communicate
    

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33. Frame types
    PUSH_PROMISE
    Used to notify the peer endpoint in advance of streams the sender
    intends to initiate
    PING
    Measuring a minimal round-trip time from the sender; checks if a
    connection is still alive
    GOAWAY Informs the remote peer to stop creating streams on this connection
    WINDOW_UPDATE
    Used to implement flow control on each individual stream or on the
    entire connection.
    CONTNUATION Used to continue a sequence of header block fragments
    

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34. Streams
    

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35. Stream
    Logical, bi-directional sequence of frames.
    

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36. Streams
    One single connection - multiple open streams.
    

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37. Priorities and dependencies
    

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38. Stream priority
    Each stream has priority
    Specified by the client (browser)
    Priority can be changed runtime
    

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39. Stream dependencies
    A stream can depend on another one.
    A
    B C
    D
    

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40. Stream dependencies
    A
    B C
    D
    A stream can depend on another one.
    

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41. Headers
    

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42. Header compression
    HTTP 2.0 is stateless protocol too
    The client still has to send data to the server
    The headers in HTTP 2.0 are compressed
    

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43. Header compression
    Stateful
    Using a single compression context for the
    entire connection
    The algorithm is called HPACK (Header
    Compression for HTTP/2)
    

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44. Header compression
    HPACK has been invented because
    of attacks like CRIME and BREACH
    

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45. Server push
    (we did that for years)
    

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46. Server push
    Server pre-emptively sends resources to a client,
    in association with a previous client-initiated
    request
    

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47. Server push
    The client explicitly must allow it
    A client cannot push
    

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48. HTTP/2 rulez!
    

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49. QUIC protocol
    

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50. QUIC Features
    Natural extension of SPDY/HTTP 2.0 research
    Multiplexing transport protocol
    Runs on top of UDP
    

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51. Why not SCTP over DTLS?
    After all, SCTP provides (among other things) stream
    multiplexing
    And DTLS provides SSL quality encryption and
    authentication over a UDP stream
    

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52. Why not SCTP over DTLS?
    Mainly because roughly 4 round trips are needed to
    establish an SCTP over DTLS connection
    In contrast, the goal of QUIC is to perform a connection
    establishment with zero RTT overhead
    

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53. Goal: 0-RTT (round-trip time) connectivity
    overhead
    Has all the benefits of SPDY/HTTP 2.0
    QUIC Features
    but...
    

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54. QUIC Features
    No head-of-line blocking in QUIC!
    

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55. QUIC Features
    Delay of only one packet causes the entire set of
    SPDY (aka HTTP/2) streams to pause.
    (Since TCP only provides a single serialized stream interface)
    In QUIC, when a single packet is lost,
    only one stream is being delayed
    

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56. QUIC Features
    No head-of-line blocking in QUIC!
    

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57. QUIC Features
    100 ms
    0 ms RTT
    Repeat connection
    New connection
    QUIC TCP + TLS
    300 ms
    200 ms RTT
    Repeat connection
    New connection
    

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58. QUIC Encryption
    Comparable to TLS, with more efficient handshake
    Replay attack and IP Spoofing protection
    

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59. QUIC Forward error correction
    

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60. QUIC Internet connections persistence
    Communication channels are not defined by IP
    +Port but by an ID
    You leave a WiFi zone and entering a mobile one
    but the connection continues
    

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61. Demo time
    

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63. https://http2rulez.com
    Open Source platform for testing different
    optimization strategies for HTTP 2.0
    Same content, served via HTTP, HTTPS, SPDY and
    HTTP/2
    (No QUIC endpoint yet)
    View Page Load Time for each page
    

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64. HTTPS Waterfall
    HTTPS waterfall
    

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65. HTTPS connection view
    

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66. HTTP/2 waterfall without server push
    

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67. HTTP/2 connection view without server push
    

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68. HTTP/2 waterfall with server push
    

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69. HTTP/2 connection view with server push
    

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70. Wrap up
    

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71. Wrap up
    Remember the workarounds we do to speed up our
    sites?
    

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72. Wrap up
    Ask yourself
    

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73. Wrap up
    How HTTP 2.0 will affect the way
    YOU
    develop and optimize Web applications?
    

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74. Thank you!
    ipeychev
    

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