<s>
Segment	B-Architecture
protection	I-Architecture
is	O
a	O
type	O
of	O
backup	O
technique	O
that	O
can	O
be	O
used	O
in	O
most	O
networks	O
.	O
</s>
<s>
Segment	B-Architecture
protection	I-Architecture
path	O
-	O
is	O
the	O
working	O
path	O
where	O
the	O
broken	O
segment	O
is	O
using	O
the	O
protected	O
path	O
.	O
</s>
<s>
We	O
can	O
see	O
that	O
segment	B-Architecture
protection	I-Architecture
has	O
been	O
implemented	O
.	O
</s>
<s>
Note	O
:	O
in	O
this	O
case	O
the	O
segment	B-Architecture
protection	I-Architecture
path	O
for	O
segment	O
does	O
not	O
contain	O
any	O
intermediate	O
nodes	O
;	O
this	O
is	O
usually	O
not	O
the	O
case	O
,	O
but	O
the	O
example	O
would	O
follow	O
respectively	O
.	O
</s>
<s>
Overlapping	O
and	O
non-overlapping	O
segment	B-Architecture
protection	I-Architecture
have	O
one	O
main	O
difference	O
but	O
provide	O
different	O
protections	O
at	O
different	O
costs	O
.	O
</s>
<s>
The	O
overlapping	O
scheme	O
makes	O
sure	O
that	O
there	O
is	O
at	O
least	O
one	O
link	O
that	O
is	O
protected	O
by	O
two	O
segments	O
,	O
while	O
the	O
non-overlapping	O
scheme	O
begins	O
a	O
segment	B-Architecture
protection	I-Architecture
at	O
the	O
same	O
node	O
as	O
the	O
previous	O
ended	O
.	O
</s>
<s>
Non-overlapping	O
segment	B-Architecture
protection	I-Architecture
does	O
not	O
provide	O
node	O
protection	O
at	O
every	O
node	O
.	O
</s>
<s>
Non-overlapping	O
segment	B-Architecture
protection	I-Architecture
is	O
a	O
more	O
cost	O
efficient	O
solution	O
because	O
only	O
the	O
end	O
node	O
of	O
every	O
segment	O
requires	O
to	O
have	O
extra	O
ports	O
.	O
</s>
<s>
In	O
the	O
long	O
term	O
it	O
is	O
more	O
cost	O
efficient	O
to	O
implement	O
overlapping	O
segment	B-Architecture
protection	I-Architecture
because	O
the	O
a	O
provisioned	O
circuit	O
's	O
availability	O
would	O
be	O
much	O
higher	O
.	O
</s>
<s>
Dedicated	O
segment	B-Architecture
protection	I-Architecture
and	O
shared	O
segment	B-Architecture
protection	I-Architecture
are	O
both	O
available	O
for	O
use	O
.	O
</s>
<s>
Shared	O
segment	B-Architecture
protection	I-Architecture
allows	O
a	O
more	O
efficient	O
network	O
to	O
be	O
deployed	O
.	O
</s>
<s>
The	O
"	O
working	O
path	O
"	O
diagram	O
illustrates	O
the	O
dedicated-overlapping	O
segment	B-Architecture
protection	I-Architecture
.	O
</s>
<s>
"	O
Shared	O
segment	B-Architecture
protection	I-Architecture
"	O
,	O
on	O
the	O
right	O
,	O
illustrated	O
a	O
shared-non-overlapping	O
segment	B-Architecture
protection	I-Architecture
.	O
</s>
<s>
Working	O
paths	O
,	O
A	O
and	O
B	O
,	O
both	O
have	O
segment	B-Architecture
protection	I-Architecture
.	O
</s>
<s>
The	O
first	O
segment	B-Architecture
protection	I-Architecture
path	O
consists	O
of	O
,	O
node	O
A	O
to	O
B	O
to	O
C	O
to	O
D	O
and	O
the	O
second	O
consists	O
of	O
,	O
node	O
D	O
to	O
E	O
to	O
F	O
.	O
In	O
this	O
example	O
we	O
can	O
see	O
that	O
if	O
part	O
of	O
working	O
path	O
A	O
,	O
node	O
D	O
to	O
F	O
,	O
would	O
fail	O
that	O
node	O
D	O
would	O
use	O
its	O
shred	O
segment	B-Architecture
protection	I-Architecture
for	O
that	O
segment	O
.	O
</s>
<s>
Shared	O
segment	B-Architecture
protection	I-Architecture
provides	O
a	O
higher	O
efficiency	O
.	O
</s>
<s>
In	O
the	O
previous	O
example	O
we	O
can	O
see	O
that	O
a	O
new	O
backup	O
segment	B-Architecture
protection	I-Architecture
is	O
not	O
necessary	O
for	O
each	O
working	O
path	O
.	O
</s>
