<s>
HTTP/2	B-Protocol
(	O
originally	O
named	O
HTTP/2.0	B-Protocol
)	O
is	O
a	O
major	O
revision	O
of	O
the	O
HTTP	B-Protocol
network	O
protocol	O
used	O
by	O
the	O
World	O
Wide	O
Web	O
.	O
</s>
<s>
It	O
was	O
derived	O
from	O
the	O
earlier	O
experimental	O
SPDY	B-Protocol
protocol	O
,	O
originally	O
developed	O
by	O
Google	B-Application
.	I-Application
</s>
<s>
HTTP/2	B-Protocol
was	O
developed	O
by	O
the	O
HTTP	B-Protocol
Working	O
Group	O
(	O
also	O
called	O
httpbis	B-Protocol
,	O
where	O
""	O
means	O
"	O
twice	O
"	O
)	O
of	O
the	O
Internet	O
Engineering	O
Task	O
Force	O
(	O
IETF	O
)	O
.	O
</s>
<s>
HTTP/2	B-Protocol
is	O
the	O
first	O
new	O
version	O
of	O
HTTP	B-Protocol
since	O
HTTP/1.1	B-Protocol
,	O
which	O
was	O
standardized	O
in	O
in	O
1997	O
.	O
</s>
<s>
The	O
Working	O
Group	O
presented	O
HTTP/2	B-Protocol
to	O
the	O
Internet	O
Engineering	O
Steering	O
Group	O
(	O
IESG	O
)	O
for	O
consideration	O
as	O
a	O
Proposed	O
Standard	O
in	O
December	O
2014	O
,	O
and	O
IESG	O
approved	O
it	O
to	O
publish	O
as	O
Proposed	O
Standard	O
on	O
February	O
17	O
,	O
2015	O
(	O
and	O
was	O
updated	O
in	O
February	O
2020	O
in	O
regard	O
to	O
TLS	O
1.3	O
)	O
.	O
</s>
<s>
The	O
HTTP/2	B-Protocol
specification	O
was	O
published	O
as	O
on	O
May	O
14	O
,	O
2015	O
.	O
</s>
<s>
The	O
standardization	O
effort	O
was	O
supported	O
by	O
Chrome	B-Application
,	O
Opera	B-Application
,	O
Firefox	B-Application
,	O
Internet	B-Application
Explorer	I-Application
11	I-Application
,	O
Safari	B-Application
,	O
Amazon	B-Protocol
Silk	I-Protocol
,	O
and	O
Edge	B-Application
browsers	I-Application
.	O
</s>
<s>
Most	O
major	O
browsers	B-Application
had	O
added	O
HTTP/2	B-Protocol
support	O
by	O
the	O
end	O
of	O
2015	O
.	O
</s>
<s>
About	O
97%	O
of	O
web	B-Application
browsers	I-Application
used	O
have	O
the	O
capability	O
.	O
</s>
<s>
,	O
39%	O
(	O
after	O
topping	O
out	O
at	O
just	O
over	O
50%	O
)	O
of	O
the	O
top	O
10	O
million	O
websites	O
supported	O
HTTP/2	B-Protocol
.	O
</s>
<s>
Its	O
successor	O
is	O
HTTP/3	B-Protocol
,	O
a	O
major	O
revision	O
that	O
builds	O
on	O
the	O
concepts	O
established	O
by	O
HTTP/2	B-Protocol
.	O
</s>
<s>
Create	O
a	O
negotiation	O
mechanism	O
that	O
allows	O
clients	O
and	O
servers	O
to	O
elect	O
to	O
use	O
HTTP/1.1	B-Protocol
,	O
2.0	O
,	O
or	O
potentially	O
other	O
non-HTTP	O
protocols	O
.	O
</s>
<s>
Maintain	O
high-level	O
compatibility	O
with	O
HTTP/1.1	B-Protocol
(	O
for	O
example	O
with	O
methods	O
,	O
status	B-Protocol
codes	I-Protocol
,	O
URIs	B-Protocol
,	O
and	O
most	O
header	B-Protocol
fields	I-Protocol
)	O
.	O
</s>
<s>
Decrease	O
latency	O
to	O
improve	O
page	O
load	O
speed	O
in	O
web	B-Application
browsers	I-Application
by	O
considering	O
:	O
</s>
<s>
Support	O
common	O
existing	O
use	O
cases	O
of	O
HTTP	B-Protocol
,	O
such	O
as	O
desktop	O
web	B-Application
browsers	I-Application
,	O
mobile	O
web	B-Application
browsers	I-Application
,	O
web	O
APIs	O
,	O
web	B-Application
servers	I-Application
at	O
various	O
scales	O
,	O
proxy	B-Application
servers	I-Application
,	O
reverse	B-General_Concept
proxy	I-General_Concept
servers	I-Application
,	O
firewalls	B-Application
,	O
and	O
content	B-Operating_System
delivery	I-Operating_System
networks	I-Operating_System
.	O
</s>
<s>
HTTP/2	B-Protocol
leaves	O
all	O
of	O
HTTP/1.1	B-Protocol
'	O
s	O
high-level	O
semantics	O
,	O
such	O
as	O
methods	O
,	O
status	B-Protocol
codes	I-Protocol
,	O
header	B-Protocol
fields	I-Protocol
,	O
and	O
URIs	B-Protocol
,	O
the	O
same	O
.	O
</s>
<s>
However	O
,	O
minification	B-Language
is	O
not	O
necessarily	O
convenient	O
nor	O
efficient	O
and	O
may	O
still	O
require	O
separate	O
HTTP	B-Protocol
connections	O
to	O
get	O
the	O
page	O
and	O
the	O
minified	B-Language
resources	O
.	O
</s>
<s>
HTTP/2	B-Protocol
allows	O
the	O
server	O
to	O
"	O
push	O
"	O
content	O
,	O
that	O
is	O
,	O
to	O
respond	O
with	O
data	O
for	O
more	O
queries	O
than	O
the	O
client	O
requested	O
.	O
</s>
<s>
This	O
allows	O
the	O
server	O
to	O
supply	O
data	O
it	O
knows	O
a	O
web	B-Application
browser	I-Application
will	O
need	O
to	O
render	O
a	O
web	O
page	O
,	O
without	O
waiting	O
for	O
the	O
browser	B-Application
to	O
examine	O
the	O
first	O
response	O
,	O
and	O
without	O
the	O
overhead	O
of	O
an	O
additional	O
request	O
cycle	O
.	O
</s>
<s>
Additional	O
performance	O
improvements	O
in	O
the	O
first	O
draft	O
of	O
HTTP/2	B-Protocol
(	O
which	O
was	O
a	O
copy	O
of	O
SPDY	B-Protocol
)	O
come	O
from	O
multiplexing	B-Architecture
of	O
requests	O
and	O
responses	O
to	O
avoid	O
some	O
of	O
the	O
head-of-line	B-Protocol
blocking	I-Protocol
problem	O
in	O
HTTP1	O
(	O
even	O
when	O
HTTP	B-Protocol
pipelining	I-Protocol
is	O
used	O
)	O
,	O
header	O
compression	B-General_Concept
,	O
and	O
prioritization	O
of	O
requests	O
.	O
</s>
<s>
However	O
,	O
as	O
HTTP/2	B-Protocol
runs	O
on	O
top	O
of	O
a	O
single	O
TCP	B-Protocol
connection	O
there	O
is	O
still	O
potential	O
for	O
head-of-line	B-Protocol
blocking	I-Protocol
to	O
occur	O
if	O
TCP	B-Protocol
packets	O
are	O
lost	O
or	O
delayed	O
in	O
transmission	O
.	O
</s>
<s>
HTTP/2	B-Protocol
no	O
longer	O
supports	O
HTTP/1.1	B-Protocol
'	O
s	O
chunked	B-Protocol
transfer	I-Protocol
encoding	I-Protocol
mechanism	O
,	O
as	O
it	O
provides	O
its	O
own	O
,	O
more	O
efficient	O
,	O
mechanisms	O
for	O
data	O
streaming	O
.	O
</s>
<s>
SPDY	B-Protocol
(	O
pronounced	O
like	O
"	O
speedy	O
"	O
)	O
was	O
a	O
previous	O
HTTP-replacement	O
protocol	O
developed	O
by	O
a	O
research	O
project	O
spearheaded	O
by	O
Google	B-Application
.	I-Application
</s>
<s>
Primarily	O
focused	O
on	O
reducing	O
latency	O
,	O
SPDY	B-Protocol
uses	O
the	O
same	O
TCP	B-Protocol
pipe	O
but	O
different	O
protocols	O
to	O
accomplish	O
this	O
reduction	O
.	O
</s>
<s>
The	O
basic	O
changes	O
made	O
to	O
HTTP/1.1	B-Protocol
to	O
create	O
SPDY	B-Protocol
included	O
:	O
"	O
true	O
request	O
pipelining	O
without	O
FIFO	O
restrictions	O
,	O
message	O
framing	O
mechanism	O
to	O
simplify	O
client	O
and	O
server	O
development	O
,	O
mandatory	O
compression	B-General_Concept
(	O
including	O
headers	O
)	O
,	O
priority	O
scheduling	O
,	O
and	O
even	O
bi-directional	O
communication	O
"	O
.	O
</s>
<s>
The	O
HTTP	B-Protocol
Working	O
Group	O
considered	O
Google	B-Application
's	I-Application
SPDY	B-Protocol
protocol	O
,	O
Microsoft	O
's	O
HTTP	B-Protocol
Speed+Mobility	I-Protocol
proposal	O
(	O
SPDY	B-Protocol
based	O
)	O
,	O
and	O
Network-Friendly	O
HTTP	B-Protocol
Upgrade	O
.	O
</s>
<s>
In	O
July	O
2012	O
,	O
Facebook	B-Application
provided	O
feedback	O
on	O
each	O
of	O
the	O
proposals	O
and	O
recommended	O
HTTP/2	B-Protocol
be	O
based	O
on	O
SPDY	B-Protocol
.	O
</s>
<s>
The	O
initial	O
draft	O
of	O
HTTP/2	B-Protocol
was	O
published	O
in	O
November	O
2012	O
and	O
was	O
based	O
on	O
a	O
straight	O
copy	O
of	O
SPDY	B-Protocol
.	O
</s>
<s>
The	O
biggest	O
difference	O
between	O
HTTP/1.1	B-Protocol
and	O
SPDY	B-Protocol
was	O
that	O
each	O
user	O
action	O
in	O
SPDY	B-Protocol
is	O
given	O
a	O
"	O
stream	O
ID	O
"	O
,	O
meaning	O
there	O
is	O
a	O
single	O
TCP	B-Protocol
channel	O
connecting	O
the	O
user	O
to	O
the	O
server	O
.	O
</s>
<s>
SPDY	B-Protocol
split	O
requests	O
into	O
either	O
control	O
or	O
data	O
,	O
using	O
a	O
"	O
simple	O
to	O
parse	O
binary	O
protocol	O
with	O
two	O
types	O
of	O
frames	O
"	O
.	O
</s>
<s>
SPDY	B-Protocol
showed	O
evident	O
improvement	O
over	O
HTTP	B-Protocol
,	O
with	O
a	O
new	O
page	O
load	O
speedup	O
ranging	O
from	O
11%	O
to	O
47%	O
.	O
</s>
<s>
The	O
development	O
of	O
HTTP/2	B-Protocol
used	O
SPDY	B-Protocol
as	O
a	O
jumping-off	O
point	O
.	O
</s>
<s>
Among	O
the	O
many	O
detailed	O
differences	O
between	O
the	O
protocols	O
,	O
the	O
most	O
notable	O
is	O
that	O
HTTP/2	B-Protocol
uses	O
a	O
fixed	O
Huffman	O
code-based	O
header	O
compression	B-General_Concept
algorithm	I-General_Concept
,	O
instead	O
of	O
SPDY	B-Protocol
's	O
dynamic	O
stream-based	O
compression	B-General_Concept
.	O
</s>
<s>
This	O
helps	O
to	O
reduce	O
the	O
potential	O
for	O
compression	B-General_Concept
oracle	I-General_Concept
attacks	I-General_Concept
on	O
the	O
protocol	O
,	O
such	O
as	O
the	O
CRIME	O
attack	O
.	O
</s>
<s>
On	O
February	O
9	O
,	O
2015	O
,	O
Google	B-Application
announced	O
plans	O
to	O
remove	O
support	O
for	O
SPDY	B-Protocol
in	O
Chrome	B-Application
in	O
favor	O
of	O
support	O
for	O
HTTP/2	B-Protocol
.	O
</s>
<s>
That	O
took	O
effect	O
,	O
starting	O
with	O
Chrome	B-Application
51	O
.	O
</s>
<s>
HTTP/2	B-Protocol
is	O
defined	O
both	O
for	O
HTTP	B-Protocol
URIs	B-Protocol
(	O
i.e.	O
</s>
<s>
without	O
TLS	O
encryption	O
,	O
a	O
configuration	O
which	O
is	O
abbreviated	O
in	O
)	O
and	O
for	O
HTTPS	B-Protocol
URIs	B-Protocol
(	O
over	O
TLS	O
using	O
ALPN	B-Protocol
extension	O
where	O
TLS	O
1.2	O
or	O
newer	O
is	O
required	O
,	O
a	O
configuration	O
which	O
is	O
abbreviated	O
in	O
)	O
.	O
</s>
<s>
Although	O
the	O
standard	O
itself	O
does	O
not	O
require	O
usage	O
of	O
encryption	O
,	O
all	O
major	O
client	O
implementations	O
(	O
Firefox	B-Application
,	O
Chrome	B-Application
,	O
Safari	B-Application
,	O
Opera	B-Application
,	O
IE	O
,	O
Edge	B-Application
)	O
have	O
stated	O
that	O
they	O
will	O
only	O
support	O
HTTP/2	B-Protocol
over	O
TLS	O
,	O
which	O
makes	O
encryption	O
de	O
facto	O
mandatory	O
.	O
</s>
<s>
The	O
FreeBSD	B-Operating_System
and	O
Varnish	B-Language
developer	O
Poul-Henning	O
Kamp	O
asserts	O
that	O
the	O
standard	O
was	O
prepared	O
on	O
an	O
unrealistically	O
short	O
schedule	O
,	O
ruling	O
out	O
any	O
basis	O
for	O
the	O
new	O
HTTP/2	B-Protocol
other	O
than	O
the	O
SPDY	B-Protocol
protocol	O
and	O
resulting	O
in	O
other	O
missed	O
opportunities	O
for	O
improvement	O
.	O
</s>
<s>
He	O
also	O
states	O
that	O
the	O
protocol	O
violates	O
the	O
protocol	O
layering	O
principle	O
,	O
for	O
example	O
by	O
duplicating	O
flow	O
control	O
that	O
belongs	O
in	O
the	O
transport	O
layer	O
(	O
TCP	B-Protocol
)	O
.	O
</s>
<s>
He	O
also	O
suggested	O
that	O
the	O
new	O
protocol	O
should	O
have	O
removed	O
HTTP	B-Application
Cookies	I-Application
,	O
introducing	O
a	O
breaking	O
change	O
.	O
</s>
<s>
Critics	O
stated	O
that	O
encryption	O
has	O
non-negligible	O
computing	O
costs	O
and	O
that	O
many	O
HTTP	B-Protocol
applications	O
actually	O
have	O
no	O
need	O
for	O
encryption	O
and	O
their	O
providers	O
have	O
no	O
desire	O
to	O
spend	O
additional	O
resources	O
on	O
it	O
.	O
</s>
<s>
Poul-Henning	O
Kamp	O
has	O
criticized	O
the	O
IETF	O
for	O
hastily	O
standardizing	O
Google	B-Application
's	I-Application
SPDY	B-Protocol
prototype	O
as	O
HTTP/2	B-Protocol
due	O
to	O
political	O
considerations	O
.	O
</s>
<s>
The	O
HTTP/2	B-Protocol
protocol	O
also	O
faced	O
criticism	O
for	O
not	O
supporting	O
opportunistic	B-Protocol
encryption	I-Protocol
,	O
a	O
measure	O
against	O
passive	O
monitoring	O
similar	O
to	O
the	O
STARTTLS	O
mechanism	O
that	O
has	O
long	O
been	O
available	O
in	O
other	O
Internet	O
protocols	O
like	O
SMTP	B-Protocol
.	O
</s>
<s>
Critics	O
have	O
stated	O
that	O
the	O
HTTP/2	B-Protocol
proposal	O
goes	O
in	O
violation	O
of	O
IETF	O
's	O
own	O
"	O
Pervasive	O
Monitoring	O
Is	O
an	O
Attack	O
"	O
,	O
which	O
also	O
has	O
a	O
status	O
of	O
Best	O
Current	O
Practice	O
188	O
.	O
</s>
<s>
RFC7258/BCP188	O
mandates	O
that	O
passive	O
monitoring	O
be	O
considered	O
as	O
an	O
attack	O
,	O
and	O
protocols	O
designed	O
by	O
IETF	O
should	O
take	O
steps	O
to	O
protect	O
against	O
passive	O
monitoring	O
(	O
for	O
example	O
,	O
through	O
the	O
use	O
of	O
opportunistic	B-Protocol
encryption	I-Protocol
)	O
.	O
</s>
<s>
A	O
number	O
of	O
specifications	O
for	O
opportunistic	B-Protocol
encryption	I-Protocol
of	O
HTTP/2	B-Protocol
have	O
been	O
provided	O
,	O
of	O
which	O
draft-nottingham-http2-encryption	O
was	O
adopted	O
as	O
an	O
official	O
work	O
item	O
of	O
the	O
working	O
group	O
,	O
leading	O
to	O
the	O
publication	O
of	O
in	O
May	O
2017	O
.	O
</s>
<s>
Although	O
the	O
design	O
of	O
HTTP/2	B-Protocol
effectively	O
addresses	O
the	O
HTTP-transaction-level	O
head-of-line	B-Protocol
blocking	I-Protocol
problem	O
by	O
allowing	O
multiple	O
concurrent	O
HTTP	B-Protocol
transactions	O
,	O
all	O
those	O
transactions	O
are	O
multiplexed	B-Architecture
over	O
a	O
single	O
TCP	B-Protocol
connection	O
,	O
meaning	O
that	O
any	O
packet-level	O
head-of-line	B-Protocol
blocking	I-Protocol
of	O
the	O
TCP	B-Protocol
stream	O
simultaneously	O
blocks	O
all	O
transactions	O
being	O
accessed	O
via	O
that	O
connection	O
.	O
</s>
<s>
This	O
head-of-line	B-Protocol
blocking	I-Protocol
in	O
HTTP/2	B-Protocol
is	O
now	O
widely	O
regarded	O
as	O
a	O
design	O
flaw	O
,	O
and	O
much	O
of	O
the	O
effort	O
behind	O
QUIC	B-Protocol
and	O
HTTP/3	B-Protocol
has	O
been	O
devoted	O
to	O
reduce	O
head-of-line	B-Protocol
blocking	I-Protocol
issues	O
.	O
</s>
<s>
Apache	O
2.4.12	O
supports	O
HTTP/2	B-Protocol
via	O
the	O
module	O
mod_h2	O
,	O
although	O
appropriate	O
patches	O
must	O
be	O
applied	O
to	O
the	O
source	O
code	O
of	O
the	O
server	O
in	O
order	O
for	O
it	O
to	O
support	O
that	O
module	O
.	O
</s>
<s>
As	O
of	O
Apache	B-Application
2.4.17	O
all	O
patches	O
are	O
included	O
in	O
the	O
main	O
Apache	B-Application
source	O
tree	O
,	O
although	O
the	O
module	O
itself	O
was	O
renamed	O
mod_http2	O
.	O
</s>
<s>
Old	O
versions	O
of	O
SPDY	B-Protocol
were	O
supported	O
via	O
the	O
module	O
mod_spdy	O
,	O
however	O
the	O
development	O
of	O
the	O
mod_spdy	O
module	O
has	O
stopped	O
.	O
</s>
<s>
Apache	B-Language
Tomcat	I-Language
supports	O
HTTP/2	B-Protocol
with	O
version	O
8.5	O
and	O
newer	O
with	O
a	O
configuration	O
change	O
.	O
</s>
<s>
Apache	B-Language
Traffic	I-Language
Server	I-Language
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
Caddy	B-Language
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
Charles	B-Protocol
Proxy	I-Protocol
supports	O
HTTP/2	B-Protocol
since	O
version	O
Charles	O
4	O
.	O
</s>
<s>
Citrix	O
NetScaler	O
11.x	O
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
Sucuri	O
Supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
F5	O
BIG-IP	O
Local	O
Traffic	O
Manager	O
11.6	O
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
Barracuda	O
Networks	O
WAF	O
(	O
Web	O
Application	O
Firewall	B-Application
)	O
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
h2o	O
was	O
built	O
from	O
the	O
ground	O
up	O
for	O
HTTP/2	B-Protocol
support	O
.	O
</s>
<s>
HAProxy	B-Language
1.8	O
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
Jetty	B-Language
9.3	O
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
lighttpd	B-Protocol
1.4.56	O
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
LiteSpeed	B-Protocol
Web	I-Protocol
Server	I-Protocol
5.0	O
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
Microsoft	B-Application
IIS	I-Application
supports	O
HTTP/2	B-Protocol
in	O
Windows	O
10	O
,	O
Windows	B-Device
Server	I-Device
2016	I-Device
,	O
and	O
Windows	B-Device
Server	I-Device
2019	I-Device
.	O
</s>
<s>
Netty	B-Language
4.1	O
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
nginx	B-Operating_System
1.9.5	O
supports	O
HTTP/2	B-Protocol
,	O
released	O
on	O
September	O
22	O
,	O
2015	O
,	O
using	O
module	O
ngx_http_v2_module	O
and	O
HTTP/2	B-Protocol
Server	I-Protocol
Push	I-Protocol
since	O
version	O
1.13.9	O
on	O
February	O
20	O
,	O
2018	O
.	O
</s>
<s>
Node.js	B-Language
Stable	O
support	O
since	O
8.13.0	O
.	O
</s>
<s>
(	O
5.0	O
supports	O
HTTP/2	B-Protocol
with	O
a	O
module	O
and	O
Node	O
8.4	O
introduced	O
experimental	O
built-in	O
support	O
for	O
HTTP/2	B-Protocol
.	O
)	O
</s>
<s>
for	O
ASP.NET	O
Core	O
supports	O
HTTP/2	B-Protocol
since	O
.NET	O
Core	O
2.2.0-preview	O
1	O
.	O
</s>
<s>
OpenLiteSpeed	O
1.3.11	O
and	O
1.4.8	O
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
Pulse	O
Secure	O
Virtual	O
Traffic	O
Manager	O
10.2	O
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
Radware	B-Protocol
Alteon	O
NG	O
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
ShimmerCat	B-Protocol
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
Vert.x	O
3.3	O
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
Warp	O
(	O
Haskell	B-Language
web	B-Application
server	I-Application
,	O
used	O
by	O
default	O
in	O
Yesod	B-Language
)	O
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
Wildfly	B-Language
9	I-Language
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
Akamai	B-Application
was	O
the	O
first	O
major	O
CDN	O
to	O
support	O
HTTP/2	B-Protocol
and	O
HTTP/2	B-Protocol
Server	I-Protocol
Push	I-Protocol
.	O
</s>
<s>
Microsoft	B-Application
Azure	I-Application
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
PageCDN	O
supports	O
HTTP/2	B-Protocol
out	O
of	O
the	O
box	O
and	O
provides	O
user-interface	O
to	O
setup	O
HTTP/2	B-Protocol
Server	I-Protocol
Push	I-Protocol
in	O
CDN	O
dashboard	O
.	O
</s>
<s>
CDN77	O
supports	O
HTTP/2	B-Protocol
using	O
nginx	B-Operating_System
(	O
August	O
20	O
,	O
2015	O
)	O
.	O
</s>
<s>
Cloudflare	B-Application
supports	O
HTTP/2	B-Protocol
using	O
nginx	B-Operating_System
with	O
SPDY	B-Protocol
as	O
a	O
fallback	O
for	O
browsers	B-Application
without	O
support	O
,	O
whilst	O
maintaining	O
all	O
security	O
and	O
performance	O
services	O
.	O
</s>
<s>
Cloudflare	B-Application
was	O
the	O
first	O
major	O
CDN	O
to	O
support	O
HTTP/2	B-Protocol
Server	I-Protocol
Push	I-Protocol
.	O
</s>
<s>
AWS	O
CloudFront	O
supports	O
HTTP/2	B-Protocol
since	O
September	O
7	O
,	O
2016	O
.	O
</s>
<s>
Fastly	B-General_Concept
supports	O
HTTP/2	B-Protocol
including	O
Server	O
Push	O
.	O
</s>
<s>
Imperva	O
Incapsula	O
CDN	O
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
KeyCDN	O
supports	O
HTTP/2	B-Protocol
using	O
nginx	B-Operating_System
(	O
October	O
6	O
,	O
2015	O
)	O
.	O
</s>
<s>
is	O
a	O
test	O
page	O
to	O
verify	O
if	O
your	O
server	O
supports	O
HTTP/2	B-Protocol
.	O
</s>
<s>
Voxility	O
supports	O
HTTP/2	B-Protocol
using	O
nginx	B-Operating_System
since	O
July	O
,	O
2016	O
.	O
</s>
<s>
StackPath	B-General_Concept
supports	O
HTTP/2	B-Protocol
.	O
</s>
