<s>
A	O
landline	B-Application
(	O
land	B-Application
line	I-Application
,	O
land-line	B-Application
,	O
main	O
line	O
,	O
home	B-Application
phone	I-Application
,	O
fixed-line	B-Application
,	O
and	O
wireline	O
)	O
is	O
a	O
telephone	O
connection	O
that	O
uses	O
metal	O
wires	O
or	O
optical	B-Architecture
fiber	I-Architecture
telephone	O
line	O
for	O
transmission	O
,	O
as	O
distinguished	O
from	O
a	O
mobile	O
cellular	O
network	O
,	O
which	O
uses	O
radio	O
waves	O
for	O
signal	O
transmission	O
.	O
</s>
<s>
Landline	B-Application
service	O
is	O
typically	O
provided	O
through	O
the	O
outside	O
plant	O
of	O
a	O
telephone	O
company	O
's	O
central	O
office	O
,	O
or	O
wire	O
center	O
.	O
</s>
<s>
The	O
outside	O
plant	O
comprises	O
tiers	O
of	O
cabling	O
between	O
distribution	O
points	O
in	O
the	O
exchange	O
area	O
,	O
so	O
that	O
a	O
single	O
pair	O
of	O
copper	O
wire	O
,	O
or	O
an	O
optical	B-Architecture
fiber	I-Architecture
,	O
reaches	O
each	O
subscriber	O
location	O
,	O
such	O
as	O
a	O
home	O
or	O
office	O
,	O
at	O
the	O
network	O
interface	O
.	O
</s>
<s>
The	O
telephone	O
connected	O
to	O
a	O
landline	B-Application
can	O
be	O
hard-wired	O
or	O
cordless	O
and	O
typically	O
refers	O
to	O
the	O
operation	O
of	O
wireless	O
devices	O
or	O
systems	O
in	O
fixed	O
locations	O
such	O
as	O
homes	O
.	O
</s>
<s>
The	O
United	O
Kingdom	O
had	O
23.7	O
million	O
residential	O
fixed	O
home	B-Application
phones	I-Application
.	O
</s>
<s>
The	O
number	O
of	O
landline	B-Application
subscribers	O
continuously	O
decreases	O
due	O
to	O
upgrades	O
in	O
digital	O
technology	O
and	O
the	O
conveniences	O
that	O
come	O
with	O
switching	O
to	O
wireless	O
(	O
cellular	O
)	O
or	O
Internet-based	O
alternatives	O
.	O
</s>
<s>
In	O
many	O
countries	O
,	O
landline	B-Application
service	O
has	O
not	O
been	O
readily	O
available	O
to	O
most	O
people	O
.	O
</s>
<s>
In	O
some	O
countries	O
in	O
Africa	O
,	O
the	O
rise	O
in	O
cell	O
phones	O
has	O
outpaced	O
growth	O
in	O
landline	B-Application
service	O
.	O
</s>
<s>
Between	O
1998	O
and	O
2008	O
,	O
Africa	O
added	O
only	O
2.4	O
million	O
landlines	B-Application
.	O
</s>
<s>
There	O
has	O
also	O
been	O
a	O
substantial	O
decline	O
of	O
landline	B-Application
phones	I-Application
in	O
the	O
Indian	O
subcontinent	O
,	O
in	O
urban	O
and	O
even	O
more	O
in	O
rural	O
areas	O
.	O
</s>
<s>
In	O
the	O
early	O
21st	O
century	O
,	O
the	O
landline	B-Application
telephone	I-Application
has	O
declined	O
due	O
to	O
the	O
advancement	O
of	O
mobile	O
network	O
technology	O
and	O
the	O
obsolescence	O
of	O
the	O
old	O
copper	O
wire	O
networking	O
.	O
</s>
<s>
It	O
is	O
more	O
difficult	O
to	O
install	O
landline	B-Application
copper	O
wires	O
to	O
every	O
user	O
than	O
it	O
is	O
to	O
install	O
mobile	O
wireless	O
towers	O
that	O
many	O
people	O
can	O
connect	O
to	O
.	O
</s>
<s>
Eventually	O
these	O
metallic	O
networks	O
will	O
be	O
deemed	O
completely	O
out	O
of	O
date	O
and	O
replaced	O
by	O
more	O
efficient	O
broadband	O
and	O
fiber	B-Architecture
optic	I-Architecture
landline	B-Application
connections	O
extending	O
to	O
rural	O
areas	O
and	O
places	O
where	O
telecommunication	O
was	O
much	O
more	O
sparse	O
.	O
</s>
<s>
At	O
that	O
time	O
,	O
most	O
had	O
to	O
rely	O
on	O
landline	B-Application
telephones	I-Application
.	O
</s>
<s>
Almost	O
60%	O
of	O
those	O
with	O
a	O
mobile	O
had	O
a	O
smartphone	B-Application
.	O
</s>
<s>
A	O
National	O
Health	O
Interview	O
Survey	O
of	O
19,956	O
households	O
by	O
the	O
Centers	O
for	O
Disease	O
Control	O
and	O
Prevention	O
released	O
May	O
4	O
,	O
2017	O
showed	O
45.9	O
percent	O
of	O
U.S.	O
households	O
still	O
had	O
landlines	B-Application
,	O
while	O
50.8	O
percent	O
had	O
only	O
cell	O
phones	O
.	O
</s>
<s>
By	O
means	O
of	O
porting	O
,	O
voice	B-Application
over	I-Application
IP	I-Application
services	O
can	O
host	O
landline	B-Application
numbers	O
previously	O
hosted	O
on	O
traditional	O
fixed	B-Application
telephone	I-Application
networks	O
.	O
</s>
<s>
VoIP	B-Application
services	O
can	O
be	O
used	O
anywhere	O
an	O
internet	O
connection	O
is	O
available	O
on	O
many	O
devices	O
including	O
Smartphones	B-Application
,	O
giving	O
great	O
flexibility	O
to	O
where	O
calls	O
may	O
be	O
answered	O
and	O
thus	O
facilitating	O
remote	O
,	O
mobile	O
and	O
home	O
working	O
,	O
for	O
example	O
.	O
</s>
<s>
VoIP	B-Application
porting	O
allows	O
landline	B-Application
numbers	O
to	O
remain	O
in	O
use	O
,	O
whilst	O
freeing	O
them	O
from	O
actual	O
landlines	B-Application
tied	O
to	O
one	O
location	O
.	O
</s>
<s>
This	O
is	O
useful	O
where	O
landline	B-Application
numbers	O
are	O
believed	O
to	O
be	O
preferred	O
by	O
callers	O
,	O
or	O
where	O
it	O
is	O
preferable	O
that	O
legacy	O
landline	B-Application
numbers	O
remain	O
connected	O
.	O
</s>
