<s>
HTTP	B-Protocol
Speed+Mobility	I-Protocol
was	O
an	O
experimental	O
open-specification	O
communication	O
protocol	O
developed	O
primarily	O
at	O
Microsoft	O
for	O
transporting	O
web	O
content	O
.	O
</s>
<s>
HTTP	B-Protocol
Speed+Mobility	I-Protocol
was	O
similar	O
to	O
HTTP	B-Protocol
,	O
with	O
particular	O
goals	O
to	O
reduce	O
web	O
page	O
load	O
latency	O
and	O
improve	O
web	O
security	O
.	O
</s>
<s>
As	O
a	O
revision	O
of	O
Google	O
's	O
SPDY	B-Protocol
protocol	O
,	O
Microsoft	O
's	O
HTTP	B-Protocol
Speed+Mobility	I-Protocol
protocol	O
achieved	O
reduced	O
latency	O
through	O
SPDY	B-Protocol
's	O
use	O
of	O
compression	O
,	O
multiplexing	B-Architecture
,	O
and	O
prioritization	O
.	O
</s>
<s>
HTTP	B-Protocol
Speed+Mobility	I-Protocol
,	O
does	O
not	O
replace	O
HTTP	B-Protocol
.	I-Protocol
</s>
<s>
Rather	O
,	O
it	O
modifies	O
the	O
way	O
HTTP	B-Protocol
requests	I-Protocol
and	O
responses	O
are	O
sent	O
over	O
the	O
wire	O
;	O
this	O
means	O
that	O
all	O
the	O
existing	O
server-side	O
applications	O
can	O
be	O
used	O
without	O
modification	O
if	O
a	O
SPDY-compatible	O
translation	O
layer	O
is	O
put	O
in	O
place	O
.	O
</s>
<s>
When	O
sent	O
over	O
SPDY	B-Protocol
,	O
the	O
HTTP	B-Protocol
requests	I-Protocol
are	O
processed	O
,	O
tokenized	O
,	O
simplified	O
and	O
compressed	O
.	O
</s>
<s>
For	O
example	O
,	O
each	O
SPDY	B-Protocol
end-point	O
keeps	O
track	O
of	O
which	O
headers	O
have	O
been	O
sent	O
in	O
the	O
past	O
requests	O
and	O
can	O
avoid	O
resending	O
the	O
headers	O
that	O
have	O
not	O
changed	O
;	O
those	O
that	O
must	O
be	O
sent	O
are	O
sent	O
compressed	O
.	O
</s>
<s>
In	O
developing	O
HTTP	B-Protocol
Speed+Mobility	I-Protocol
,	O
Microsoft	O
built	O
upon	O
both	O
Google	O
's	O
proven	O
SPDY	B-Protocol
protocol	O
and	O
on	O
WebSocket	B-Protocol
,	O
which	O
is	O
a	O
web	O
technology	O
providing	O
for	O
bi-directional	O
,	O
full-duplex	O
communications	O
channels	O
over	O
a	O
single	O
TCP	B-Protocol
connection	O
.	O
</s>
<s>
Besides	O
support	O
of	O
the	O
framing	O
of	O
WebSockets	B-Protocol
,	O
changes	O
from	O
SPDY	B-Protocol
include	O
the	O
following	O
:	O
taking	O
mobile	O
phones	O
and	O
other	O
low-power	O
devices	O
into	O
account	O
and	O
the	O
removal	O
of	O
SPDY	B-Protocol
’s	O
obligatory	O
use	O
of	O
CPU-intensive	O
features	O
encryption	O
,	O
compression	O
,	O
and	O
server-side	O
push	O
.	O
</s>
<s>
The	O
has	O
begun	O
working	O
on	O
HTTP/2	B-Protocol
and	O
chose	O
SPDY	B-Protocol
as	O
the	O
starting	O
point	O
.	O
</s>
