<s>
Optical	B-Protocol
burst	I-Protocol
switching	I-Protocol
(	O
OBS	O
)	O
is	O
an	O
optical	O
networking	O
technique	O
that	O
allows	O
dynamic	O
sub-wavelength	O
switching	O
of	O
data	O
.	O
</s>
<s>
The	O
purpose	O
of	O
optical	B-Protocol
burst	I-Protocol
switching	I-Protocol
(	O
OBS	O
)	O
is	O
to	O
dynamically	O
provision	O
sub-wavelength	O
granularity	O
by	O
optimally	O
combining	O
electronics	O
and	O
optics	O
.	O
</s>
<s>
Various	O
assembling	O
schemes	O
based	O
on	O
time	O
and/or	O
size	O
exist	O
(	O
see	O
burst	B-General_Concept
switching	I-General_Concept
)	O
.	O
</s>
<s>
OBS	O
features	O
the	O
separation	O
between	O
the	O
control	B-Protocol
plane	I-Protocol
and	O
the	O
data	B-Protocol
plane	I-Protocol
.	O
</s>
<s>
Furthermore	O
,	O
there	O
must	O
be	O
a	O
guardband	O
in	O
the	O
data	O
channel	O
between	O
packets	O
or	O
bursts	O
,	O
so	O
that	O
core	O
optical	O
router	O
data	B-Protocol
planes	I-Protocol
have	O
adequate	O
time	O
to	O
switch	O
packets	O
or	O
bursts	O
.	O
</s>
<s>
Reduce	O
processing	O
requirements	O
and	O
core	O
network	O
energy	O
consumption	O
–	O
A	O
core	O
optical	O
router	O
in	O
an	O
OBS	O
network	O
may	O
face	O
reduced	O
control	B-Protocol
plane	I-Protocol
requirements	O
when	O
compared	O
to	O
that	O
in	O
an	O
OPS	O
network	O
,	O
as	O
:	O
A	O
core	O
optical	O
router	O
in	O
an	O
OPS	O
network	O
would	O
have	O
to	O
perform	O
processing	O
operations	O
for	O
every	O
arriving	O
packet	O
,	O
wherelse	O
in	O
an	O
OBS	O
network	O
the	O
router	O
performs	O
processing	O
operations	O
for	O
an	O
arriving	O
burst	O
which	O
contains	O
several	O
packets	O
.	O
</s>
