<s>
Wireless	B-Protocol
Application	I-Protocol
Protocol	I-Protocol
(	O
WAP	O
)	O
is	O
a	O
technical	O
standard	O
for	O
accessing	O
information	O
over	O
a	O
mobile	O
wireless	B-General_Concept
network	I-General_Concept
.	O
</s>
<s>
A	O
WAP	B-Protocol
browser	I-Protocol
is	O
a	O
web	B-Application
browser	I-Application
for	O
mobile	B-Application
devices	I-Application
such	O
as	O
mobile	O
phones	O
that	O
use	O
the	O
protocol	O
.	O
</s>
<s>
Almost	O
all	O
modern	O
handset	O
internet	B-Application
browsers	I-Application
now	O
fully	O
support	O
HTML	B-Language
,	O
so	O
they	O
do	O
not	O
need	O
to	O
use	O
WAP	O
markup	O
for	O
web	O
page	O
compatibility	O
,	O
and	O
therefore	O
,	O
most	O
are	O
no	O
longer	O
able	O
to	O
render	O
and	O
display	O
pages	O
written	O
in	O
WML	B-General_Concept
,	O
WAP	O
's	O
markup	O
language	O
.	O
</s>
<s>
The	O
WAP	O
standard	O
described	O
a	O
protocol	B-Protocol
suite	I-Protocol
or	O
stack	O
allowing	O
the	O
interoperability	O
of	O
WAP	O
equipment	O
and	O
software	O
with	O
different	O
network	O
technologies	O
,	O
such	O
as	O
GSM	O
and	O
IS-95	O
(	O
also	O
known	O
as	O
CDMA	B-Protocol
)	O
.	O
</s>
<s>
The	O
bottom-most	O
protocol	O
in	O
the	O
suite	O
,	O
the	O
Wireless	B-Protocol
Datagram	I-Protocol
Protocol	I-Protocol
(	O
WDP	O
)	O
,	O
functions	O
as	O
an	O
adaptation	O
layer	O
that	O
makes	O
every	O
data	O
network	O
look	O
a	O
bit	O
like	O
UDP	B-Protocol
to	O
the	O
upper	O
layers	O
by	O
providing	O
unreliable	O
transport	O
of	O
data	O
with	O
two	O
16-bit	O
port	O
numbers	O
(	O
origin	O
and	O
destination	O
)	O
.	O
</s>
<s>
All	O
the	O
upper	O
layers	O
view	O
WDP	O
as	O
one	O
and	O
the	O
same	O
protocol	O
,	O
which	O
has	O
several	O
"	O
technical	O
realizations	O
"	O
on	O
top	O
of	O
other	O
"	O
data	O
bearers	O
"	O
such	O
as	O
SMS	B-Device
,	O
USSD	O
,	O
etc	O
.	O
</s>
<s>
On	O
native	O
IP	O
bearers	O
such	O
as	O
GPRS	B-General_Concept
,	O
UMTS	B-Protocol
packet-radio	O
service	O
,	O
or	O
PPP	B-Protocol
on	O
top	O
of	O
a	O
circuit-switched	O
data	O
connection	O
,	O
WDP	O
is	O
in	O
fact	O
exactly	O
UDP	B-Protocol
.	O
</s>
<s>
WTLS	B-Protocol
,	O
an	O
optional	O
layer	O
,	O
provides	O
a	O
public-key	O
cryptography-based	O
security	O
mechanism	O
similar	O
to	O
TLS	B-Protocol
.	O
</s>
<s>
WTP	B-Protocol
provides	O
transaction	O
support	O
(	O
reliable	O
request/response	O
)	O
adapted	O
to	O
the	O
wireless	O
world	O
.	O
</s>
<s>
WTP	B-Protocol
supports	O
more	O
effectively	O
than	O
TCP	B-Protocol
the	O
problem	O
of	O
packet	O
loss	O
,	O
which	O
occurs	O
commonly	O
in	O
2G	O
wireless	O
technologies	O
in	O
most	O
radio	O
conditions	O
,	O
but	O
is	O
misinterpreted	O
by	O
TCP	B-Protocol
as	O
network	O
congestion	O
.	O
</s>
<s>
This	O
protocol	B-Protocol
suite	I-Protocol
allows	O
a	O
terminal	O
to	O
transmit	O
requests	O
that	O
have	O
an	O
HTTP	B-Protocol
or	O
HTTPS	B-Protocol
equivalent	O
to	O
a	O
WAP	O
gateway	O
;	O
the	O
gateway	O
translates	O
requests	O
into	O
plain	O
HTTP	B-Protocol
.	I-Protocol
</s>
<s>
For	O
WAP	O
version	O
1.X	O
,	O
the	O
primary	O
language	O
of	O
the	O
WAE	O
is	O
Wireless	B-General_Concept
Markup	I-General_Concept
Language	I-General_Concept
(	O
WML	B-General_Concept
)	O
.	O
</s>
<s>
In	O
WAP	O
2.0	O
,	O
the	O
primary	O
markup	O
language	O
is	O
XHTML	B-Language
Mobile	O
Profile	O
.	O
</s>
<s>
WAP	O
Push	O
was	O
specified	O
on	O
top	O
of	O
Wireless	B-Protocol
Datagram	I-Protocol
Protocol	I-Protocol
(	O
WDP	O
)	O
;	O
as	O
such	O
,	O
it	O
can	O
be	O
delivered	O
over	O
any	O
WDP-supported	O
bearer	O
,	O
such	O
as	O
GPRS	B-General_Concept
or	O
SMS	B-Device
.	O
</s>
<s>
Most	O
GSM	O
networks	O
have	O
a	O
wide	O
range	O
of	O
modified	O
processors	O
,	O
but	O
GPRS	B-General_Concept
activation	O
from	O
the	O
network	O
is	O
not	O
generally	O
supported	O
,	O
so	O
WAP	O
Push	O
messages	O
have	O
to	O
be	O
delivered	O
on	O
top	O
of	O
the	O
SMS	B-Device
bearer	O
.	O
</s>
<s>
A	O
variant	O
,	O
known	O
as	O
WAP	O
Push	O
SL	O
(	O
Service	O
Loading	O
)	O
,	O
directly	O
opens	O
the	O
browser	B-Application
to	O
display	O
the	O
WAP	O
content	O
,	O
without	O
user	O
interaction	O
.	O
</s>
<s>
The	O
network	O
entity	O
that	O
processes	O
WAP	O
Pushes	O
and	O
delivers	O
them	O
over	O
an	O
IP	O
or	O
SMS	B-Device
Bearer	O
is	O
known	O
as	O
a	O
Push	B-General_Concept
Proxy	I-General_Concept
Gateway	I-General_Concept
(	O
PPG	O
)	O
.	O
</s>
<s>
It	O
uses	O
a	O
cut-down	O
version	O
of	O
XHTML	B-Language
with	O
end-to-end	O
HTTP	B-Protocol
,	O
dropping	O
the	O
gateway	O
and	O
custom	O
protocol	B-Protocol
suite	I-Protocol
used	O
to	O
communicate	O
with	O
it	O
.	O
</s>
<s>
Mobile	B-Application
devices	I-Application
process	O
XHTML	B-Language
Mobile	O
Profile	O
(	O
XHTML	B-Language
MP	O
)	O
,	O
the	O
markup	O
language	O
defined	O
in	O
WAP	O
2.0	O
.	O
</s>
<s>
It	O
is	O
a	O
subset	O
of	O
XHTML	B-Language
and	O
a	O
superset	O
of	O
XHTML	B-Language
Basic	O
.	O
</s>
<s>
A	O
version	O
of	O
Cascading	B-Language
Style	I-Language
Sheets	I-Language
(	O
CSS	B-Language
)	O
called	O
WAP	O
CSS	B-Language
is	O
supported	O
by	O
XHTML	B-Language
MP	O
.	O
</s>
<s>
Multimedia	O
Messaging	O
Service	O
(	O
MMS	O
)	O
is	O
a	O
combination	O
of	O
WAP	O
and	O
SMS	B-Device
allowing	O
for	O
sending	O
of	O
picture	O
messages	O
.	O
</s>
<s>
The	O
first	O
company	O
to	O
launch	O
a	O
WAP	B-Protocol
site	I-Protocol
was	O
Dutch	O
mobile	O
phone	O
operator	O
Telfort	O
BV	O
in	O
October	O
1999	O
.	O
</s>
<s>
BT	O
Cellnet	O
,	O
one	O
of	O
the	O
UK	O
telecoms	O
,	O
ran	O
an	O
advertising	O
campaign	O
depicting	O
a	O
cartoon	O
WAP	O
user	O
surfing	O
through	O
a	O
Neuromancer-like	O
"	O
information	O
space	O
"	O
.	O
</s>
<s>
Operator	O
revenues	O
were	O
generated	O
by	O
transfer	O
of	O
GPRS	B-General_Concept
and	O
UMTS	B-Protocol
data	O
,	O
which	O
is	O
a	O
different	O
business	O
model	O
than	O
used	O
by	O
the	O
traditional	O
Web	O
sites	O
and	O
ISPs	O
.	O
</s>
<s>
Most	O
modern	O
handset	O
internet	B-Application
browsers	I-Application
now	O
support	O
full	O
HTML	B-Language
,	O
CSS	B-Language
,	O
and	O
most	O
of	O
JavaScript	B-Language
,	O
and	O
do	O
not	O
need	O
to	O
use	O
any	O
kind	O
of	O
WAP	O
markup	O
for	O
webpage	O
compatibility	O
.	O
</s>
<s>
The	O
list	O
of	O
handsets	O
supporting	O
HTML	B-Language
is	O
extensive	O
,	O
and	O
includes	O
all	O
Android	O
handsets	O
,	O
all	O
versions	O
of	O
the	O
iPhone	O
handset	O
,	O
all	O
Blackberry	O
devices	O
,	O
all	O
devices	O
running	O
Windows	O
Phone	O
,	O
and	O
many	O
Nokia	O
handsets	O
.	O
</s>
<s>
Like	O
in	O
Europe	O
,	O
WAP	O
and	O
i-mode	O
usage	O
declined	O
in	O
the	O
2010s	O
as	O
HTML-capable	O
smartphones	O
became	O
popular	O
in	O
Japan	O
.	O
</s>
<s>
Commentators	O
criticized	O
several	O
aspects	O
of	O
Wireless	B-General_Concept
Markup	I-General_Concept
Language	I-General_Concept
(	O
WML	B-General_Concept
)	O
and	O
WAP	O
.	O
</s>
<s>
The	O
idiosyncratic	O
WML	B-General_Concept
language	O
:	O
WML	B-General_Concept
cut	O
users	O
off	O
from	O
the	O
conventional	O
HTML	B-Language
Web	O
,	O
leaving	O
only	O
native	O
WAP	O
content	O
and	O
Web-to-WAP	O
proxi-content	O
available	O
to	O
WAP	O
users	O
.	O
</s>
<s>
The	O
user	O
interface	O
of	O
devices	O
was	O
also	O
underspecified	O
:	O
as	O
an	O
example	O
,	O
accesskeys	O
(	O
e.g.	O
,	O
the	O
ability	O
to	O
press	O
'	O
4	O
 '	O
to	O
access	O
directly	O
the	O
fourth	O
link	O
in	O
a	O
list	O
)	O
were	O
variously	O
implemented	O
depending	O
on	O
phone	O
models	O
(	O
sometimes	O
with	O
the	O
accesskey	O
number	O
automatically	O
displayed	O
by	O
the	O
browser	B-Application
next	O
to	O
the	O
link	O
,	O
sometimes	O
without	O
it	O
,	O
and	O
sometimes	O
accesskeys	O
were	O
not	O
implemented	O
at	O
all	O
)	O
.	O
</s>
<s>
Lack	O
of	O
good	O
authoring	O
tools	O
:	O
The	O
problems	O
above	O
might	O
have	O
succumbed	O
in	O
the	O
face	O
of	O
a	O
WML	B-General_Concept
authoring	O
tool	O
that	O
would	O
have	O
allowed	O
content	O
providers	O
to	O
easily	O
publish	O
content	O
that	O
would	O
interoperate	O
flawlessly	O
with	O
many	O
models	O
,	O
adapting	O
the	O
pages	O
presented	O
to	O
the	O
User-Agent	B-Protocol
type	O
.	O
</s>
<s>
Developing	O
for	O
the	O
web	O
was	O
easy	O
:	O
with	O
a	O
text	O
editor	O
and	O
a	O
web	B-Application
browser	I-Application
,	O
anybody	O
could	O
get	O
started	O
,	O
thanks	O
also	O
to	O
the	O
forgiving	O
nature	O
of	O
most	O
desktop	O
browser	B-Application
rendering	O
engines	O
.	O
</s>
<s>
By	O
contrast	O
,	O
the	O
stringent	O
requirements	O
of	O
the	O
WML	B-General_Concept
specifications	O
,	O
the	O
variability	O
in	O
terminals	O
,	O
and	O
the	O
demands	O
of	O
testing	O
on	O
various	O
wireless	B-General_Concept
terminals	I-General_Concept
,	O
along	O
with	O
the	O
lack	O
of	O
widely	O
available	O
desktop	O
authoring	O
and	O
emulation	O
tools	O
,	O
considerably	O
lengthened	O
the	O
time	O
required	O
to	O
complete	O
most	O
projects	O
.	O
</s>
<s>
,	O
however	O
,	O
with	O
many	O
mobile	B-Application
devices	I-Application
supporting	O
XHTML	B-Language
,	O
and	O
programs	O
such	O
as	O
Adobe	O
Go	O
Live	O
and	O
Dreamweaver	O
offering	O
improved	O
web-authoring	O
tools	O
,	O
it	O
is	O
becoming	O
easier	O
to	O
create	O
content	O
,	O
accessible	O
by	O
many	O
new	O
devices	O
.	O
</s>
<s>
Lack	O
of	O
user	B-Protocol
agent	I-Protocol
profiling	O
tools	O
:	O
It	O
quickly	O
became	O
nearly	O
impossible	O
for	O
web	O
hosts	O
to	O
determine	O
if	O
a	O
request	O
came	O
from	O
a	O
mobile	B-Application
device	I-Application
,	O
or	O
from	O
a	O
larger	O
more	O
capable	O
device	O
.	O
</s>
<s>
Lack	O
of	O
openness	O
:	O
Many	O
wireless	O
carriers	O
sold	O
their	O
WAP	O
services	O
as	O
"	O
open	O
"	O
,	O
in	O
that	O
they	O
allowed	O
users	O
to	O
reach	O
any	O
service	O
expressed	O
in	O
WML	B-General_Concept
and	O
published	O
on	O
the	O
Internet	O
.	O
</s>
<s>
However	O
,	O
they	O
also	O
made	O
sure	O
that	O
the	O
first	O
page	O
that	O
clients	O
accessed	O
was	O
their	O
own	O
"	O
wireless	B-Application
portal	I-Application
"	O
,	O
which	O
they	O
controlled	O
very	O
closely	O
.	O
</s>
<s>
Some	O
carriers	O
also	O
turned	O
off	O
editing	O
or	O
accessing	O
the	O
address	O
bar	O
in	O
the	O
device	O
's	O
browser	B-Application
.	O
</s>
<s>
To	O
facilitate	O
users	O
wanting	O
to	O
go	O
off	O
deck	O
,	O
an	O
address	O
bar	O
on	O
a	O
form	B-General_Concept
on	O
a	O
page	O
linked	O
off	O
the	O
hard	O
coded	O
home	O
page	O
was	O
provided	O
.	O
</s>
<s>
It	O
makes	O
it	O
easier	O
for	O
carriers	O
to	O
implement	O
filtering	O
of	O
off	O
deck	O
WML	B-General_Concept
sites	O
by	O
URLs	O
or	O
to	O
disable	O
the	O
address	O
bar	O
in	O
the	O
future	O
if	O
the	O
carrier	O
decides	O
to	O
switch	O
all	O
users	O
to	O
a	O
walled	B-Application
garden	I-Application
model	O
.	O
</s>
<s>
Given	O
the	O
difficulty	O
in	O
typing	O
up	O
fully	O
qualified	O
URLs	O
on	O
a	O
phone	O
keyboard	O
,	O
most	O
users	O
would	O
give	O
up	O
going	O
"	O
off	O
portal	O
"	O
or	O
out	O
of	O
the	O
walled	B-Application
garden	I-Application
;	O
by	O
not	O
letting	O
third	O
parties	O
put	O
their	O
own	O
entries	O
on	O
the	O
operators	O
 '	O
wireless	B-Application
portal	I-Application
,	O
some	O
contend	O
that	O
operators	O
cut	O
themselves	O
off	O
from	O
a	O
valuable	O
opportunity	O
.	O
</s>
<s>
The	O
original	O
WAP	O
model	O
provided	O
a	O
simple	O
platform	O
for	O
access	O
to	O
web-like	O
WML	B-General_Concept
services	O
and	O
e-mail	O
using	O
mobile	O
phones	O
in	O
Europe	O
and	O
the	O
SE	O
Asian	O
regions	O
.	O
</s>
<s>
The	O
later	O
versions	O
of	O
WAP	O
,	O
primarily	O
targeting	O
the	O
United	O
States	O
market	O
,	O
were	O
designed	O
for	O
a	O
different	O
requirement	O
-	O
to	O
enable	O
full	O
web	O
XHTML	B-Language
access	O
using	O
mobile	B-Application
devices	I-Application
with	O
a	O
higher	O
specification	O
and	O
cost	O
,	O
and	O
with	O
a	O
higher	O
degree	O
of	O
software	O
complexity	O
.	O
</s>
<s>
The	O
initial	O
design	O
of	O
WAP	O
specifically	O
aimed	O
at	O
protocol	O
independence	O
across	O
a	O
range	O
of	O
different	O
protocols	O
(	O
SMS	B-Device
,	O
IP	O
over	O
PPP	B-Protocol
over	O
a	O
circuit	O
switched	O
bearer	O
,	O
IP	O
over	O
GPRS	B-General_Concept
,	O
etc	O
.	O
)	O
.	O
</s>
<s>
WAP	O
's	O
transmission	O
layer	O
protocol	O
,	O
WTP	B-Protocol
,	O
uses	O
its	O
own	O
retransmission	O
mechanisms	O
over	O
UDP	B-Protocol
to	O
attempt	O
to	O
solve	O
the	O
problem	O
of	O
the	O
inadequacy	O
of	O
TCP	B-Protocol
over	O
high-packet-loss	O
networks	O
.	O
</s>
