<s>
In	O
telecommunication	O
,	O
a	O
shared	B-Protocol
medium	I-Protocol
is	O
a	O
medium	O
or	O
channel	O
of	O
information	O
transfer	O
that	O
serves	O
more	O
than	O
one	O
user	O
at	O
the	O
same	O
time	O
.	O
</s>
<s>
In	O
circuit	B-Protocol
switching	I-Protocol
,	O
each	O
user	O
typically	O
gets	O
a	O
fixed	O
share	O
of	O
the	O
channel	O
capacity	O
.	O
</s>
<s>
A	O
multiplexing	B-Architecture
scheme	O
divides	O
up	O
the	O
capacity	O
of	O
the	O
medium	O
.	O
</s>
<s>
Common	O
multiplexing	B-Architecture
schemes	O
include	O
time-division	B-Protocol
multiplexing	I-Protocol
and	O
frequency-division	B-Protocol
multiplexing	I-Protocol
.	O
</s>
<s>
Channel	O
access	O
methods	O
for	O
circuit	B-Protocol
switching	I-Protocol
include	O
time-division	B-Protocol
multiple	O
access	O
,	O
frequency-division	O
multiple	O
access	O
,	O
etc	O
.	O
</s>
<s>
In	O
packet	B-Protocol
switching	I-Protocol
,	O
the	O
sharing	O
is	O
more	O
dynamic	O
each	O
user	O
takes	O
up	O
little	O
or	O
none	O
of	O
the	O
capacity	O
when	O
idle	O
,	O
and	O
can	O
utilize	O
the	O
entire	O
capacity	O
if	O
transmitting	O
while	O
all	O
other	O
users	O
are	O
idle	O
.	O
</s>
<s>
Channel	O
access	O
methods	O
for	O
packet	B-Protocol
switching	I-Protocol
include	O
carrier-sense	O
multiple	O
access	O
,	O
token	B-Protocol
passing	I-Protocol
,	O
etc	O
.	O
</s>
