So that was

HTTP/2, what's next?

February 4 2017

Questions?

I’ll hang around I’ll hang around outside the outside the

room afterwardroom afterward

Daniel Stenberg@bagder

Request and payload growth

in the last 5 years ...

8080

100100

800K800K

2.5M2.5M

the average website loads 50+ resources on a single domain

Head of line blockingHead of line blocking

Multiplexed (1/2)

Multiple streams over a single physical connection

Max number of parallel streams set by peer

Multiplexed (2/2)

Better utilization of bandwidth

So that was HTTP/2 February 4, 2017

Adoption, usage, support

servers

browsers

Browser stats – Feb 2017

HTTP/2:

Share of HTTPS:

30%30%

60%60%

Internetz – February 2017

12% of top 10 million

23% of top 10,000

26% of top 1000

>50% for your site

Winners and losers

So that was HTTP/2 February 4, 2017

Did HTTP/2 meet its promises

The remote corners of Internet

Percentile Desktop Mobile

5 1 11

25 20 44

50 79 94

75 194 184

95 800 913

Milliseconds RTT

Queuing time h1 vs h2(Time waiting internally to send off a HTTP request)

Percentile HTTP 1 HTTP 2

80 100 ms 2 ms

95 2000 ms 16 ms

>100ms: H1 20%, H2 3%

0% packet loss

Image and data by Hooman Beheshti, Fastly

2% packet loss

Image and data by Hooman Beheshti, Fastly

Packet loss, hey?

Single connection vs 6

Head of line blocking

A single dropped packet blocks everything

Packet loss, hey?

TLS TLS TLS

HTTP/2 frame

HTTP/2 frame

HTTP/2 frame

HTTP/2 frame

HTTP/2 frame

IP IP IP IP IP IPTCP TCP TCP TCP

Packet loss, hey?

IP

HTTP/2 frame

HTTP/2 frame

HTTP/2 frame

HTTP/2 frame

HTTP/2 frame

TCP TCP TCP TCPTLS TLS TLS

IP IP IP IP IP IP

Fixing TCP head of blocking

A non-blocking TCP + TLS + HTTP/2

Needs independent packets

… that still are stream aware

Needs new retransmissions/ACKs

New protocol?

Fixing TCP takes decades –if even doable

QUIC

“TCP”, TLS and HTTP/2 over UDP

no TCP head of line blocking

other congestion control

move across interfaces

“TCP improvements” - much faster

Google has this widely deployed already

UDP not as problematic as we thought

Packet loss, hey?

IPUDP UDP UDP UDP UDP UDPquic quic quic quic quic quicTLS TLS TLS TLS TLS TLSh2 h2 h2 h2 h2 h2

IP IP IP IP IP IP

The IETF QUIC wg

Just started

Massive interest

s/custom crypto/TLS 1.3

Will transfer more than HTTP/2 frames

First interim meeting in Tokyo in Jan ‘17

IETF-QUIC vs Google-QUIC

Maybe early live test around mid-2017

That means That means maybemaybe and and earlyearly tests tests

Neither 3 nor 2

Perhaps “HTTP/3”, but not in name

Perhaps “TCP/2”, but not in name

Just QUIC

Round-up

HTTP/1 is not optimal

HTTP/2 is binary and multipled

HTTP/2 is widely used

HTTP/2 makes sites faster

(IETF-)QUIC is coming

QUIC is HTTP/2 frames over UDP

Thank you!

Questions outside!