HTTP/2 right now
Daniel Stenberg, February 1st
2015

Agenda
HTTP Today
HTTP/2 basics
Status
Future
Q&A

Daniel Stenberg
Email: daniel@haxx.se
Twitter: @bagder
Web: daniel.haxx.se
Blog: daniel.haxx.se/blog
network hacker at

Please ask!
… but wait for the Q&A and if not enough, just catch
me afterward.

Today
HTTP for everything
The web has changed significantly since 1996

Request and payload growth
in 4 years...
7777
100100
725K725K
1900K1900K
httparchive.org

connections per page
38
httparchive.org

Latency adds up
4,000 ms
750 ms
Page
load
time
Round
trip
time0 ms 240 ms
MikeBelshe

Head of line blocking

HTTP 1.1 work-arounds

Spriting

Inlining
.icon1 {
background: url(data:image/png;base64,<data>) no-repeat;
}
.icon2 {
background: url(data:image/png;base64,<data>) no-repeat;
}

Concatenation
$ cat *.js > a-single-monster.js

Sharding

Quirky work-arounds
Annoying for developers
Adds layers of tools
Hampers caching
Downloads too much

HTTP/2

“Just a new framing layer”
maintains HTTP paradigms
http:// and https:// URLs cannot be changed
HTTP/1.1 servers and clients will be around for
decades
Proxies must be able to convert 1:1
Less optional parts
No more minor version!

HTTP/2 framing
Binary
Multiplexed streams; with individual
priorities, dependencies and flow-control
Header compression
Server push

HTTP/2 is not
Mandatory TLS
Changing HTTP headers

How will HTTP/2 affect web users?
Faster page loads
More responsive loading

How will HTTP/2 affect web development?
HTTP/1 work-arounds hurt HTTP/2 perf
Need to do separate tweaks
Maximum HTTP/2 usage will need some time

Implementations
Nghttp2
Http2-katana
Node-http2
Firefox
Http2-perl
Iij-http2
Akamai
Chrome
Twitter
Wireshark
Ericsson
MSP
Http2 (Go)
Http2-go
OkHttp
Trusterd
Google GFE
Deuterium
Hyper
Undertow
F5
Sasazka
Lucid
H2O
curl
Cl-http2
Netty
Jetty
Microsoft
Http-2
Apache
nginx
https://github.com/http2/http2-spec/wiki/Implementations

Will HTTP/2 get widely deployed?
“Look at IPv6”
SPDY proved fast growth can happen
Major browsers are on the train
Many sites already did SPDY - likely to go HTTP/2

How will HTTP/2 affect web development?
HTTP/1 work-arounds hurt http2 perf
Need to do separate tweaks
Maximum HTTP/2 usage will need some time

HTTP/2 – Status of February 1st
2015
Firefox: HTTP/2 in 9%of all HTTP responses1
HTTP/2 is used 9 times more than HTTP/1.0
Google: HTTP/2 used in 5% of global traffic2
IPv6: 5% today, almost 20 years after first RFC
1. Rough and not statistically sound numbers from Mozilla Telemetry data for Firefox 35.
2. Rough and rapidly changing numbers in an evolving climate. Graciously provided by Google.

Schedule
IETF Last Call ended on January 14th
Firefox 35 – enabled by default January 13th
Chrome 40 – enabled by default January 21st
HTTP/2 final RFC in Q1 2015 ?

HTTP/3 ?
HTTP/2 lays the foundation for the future
Time to drop legacy HTTP “mistakes”?
HTTP/3 can happen sooner than the 1.1 to 2 took

Thank you!
See also http2 explained:
http://daniel.haxx.se/http2

Doing good is part of our code

Credits
✗
HTTP and TCP trend numbers from
http://httparchive.org
✗
RTT / page load data from Mike Belshe
✗
HTTP/2 usage numbers by Google and Firefox
Telemetry
✗
Lego pieces borrowed from my kids

License
This presentation and its contents are licensed under
the Creative Commons Attribution 4.0 license:
http://creativecommons.org/licenses/by/4.0/