<s>
G.9972	B-Protocol
(	O
also	O
known	O
as	O
G.cx	B-Protocol
)	O
is	O
a	O
Recommendation	O
developed	O
by	O
ITU-T	O
that	O
specifies	O
a	O
coexistence	O
mechanism	O
for	O
networking	O
transceivers	O
capable	O
of	O
operating	O
over	O
electrical	O
power	O
line	O
wiring	O
.	O
</s>
<s>
It	O
allows	O
G.hn	B-General_Concept
devices	O
to	O
coexist	O
with	O
other	O
devices	O
implementing	O
G.9972	B-Protocol
and	O
operating	O
on	O
the	O
same	O
power	O
line	O
wiring	O
.	O
</s>
<s>
G.9972	B-Protocol
received	O
consent	O
during	O
the	O
meeting	O
of	O
ITU-T	O
Study	O
Group	O
15	O
,	O
on	O
October	O
9	O
,	O
2009	O
,	O
and	O
final	O
approval	O
on	O
June	O
11	O
,	O
2010	O
.	O
</s>
<s>
G.9972	B-Protocol
specifies	O
two	O
mechanisms	O
for	O
coexistence	O
between	O
G.hn	B-General_Concept
home	O
networks	O
and	O
broadband	O
over	O
power	O
lines	O
(	O
BPL	O
)	O
Internet	O
access	O
networks	O
:	O
</s>
<s>
Frequency-division	B-Protocol
multiplexing	I-Protocol
(	O
FDM	O
)	O
,	O
in	O
which	O
the	O
available	O
spectrum	O
is	O
divided	O
into	O
two	O
parts	O
:	O
frequencies	O
below	O
10	O
or	O
14MHz	O
(	O
specific	O
value	O
can	O
be	O
selected	O
by	O
the	O
access	O
network	O
)	O
are	O
reserved	O
for	O
the	O
access	O
network	O
,	O
while	O
frequencies	O
above	O
them	O
are	O
reserved	O
for	O
the	O
in-home	O
network	O
.	O
</s>
<s>
Time-division	B-Protocol
multiplexing	I-Protocol
(	O
TDM	O
)	O
,	O
in	O
which	O
the	O
available	O
channel	O
time	O
is	O
split	O
equally	O
between	O
both	O
networks	O
.	O
</s>
