<s>
Switched	B-Architecture
fabric	I-Architecture
or	O
switching	B-Architecture
fabric	I-Architecture
is	O
a	O
network	B-Architecture
topology	I-Architecture
in	O
which	O
network	B-Protocol
nodes	I-Protocol
interconnect	B-General_Concept
via	O
one	O
or	O
more	O
network	B-Protocol
switches	I-Protocol
(	O
particularly	O
crossbar	O
switches	O
)	O
.	O
</s>
<s>
Because	O
a	O
switched	B-Architecture
fabric	I-Architecture
network	O
spreads	O
network	O
traffic	O
across	O
multiple	O
physical	O
links	O
,	O
it	O
yields	O
higher	O
total	O
throughput	O
than	O
broadcast	B-Operating_System
networks	I-Operating_System
,	O
such	O
as	O
the	O
early	O
10BASE5	O
version	O
of	O
Ethernet	O
and	O
most	O
wireless	B-General_Concept
networks	I-General_Concept
such	O
as	O
Wi-Fi	O
.	O
</s>
<s>
The	O
generation	O
of	O
high-speed	O
serial	B-Protocol
data	I-Protocol
interconnects	I-Protocol
that	O
appeared	O
in	O
2001	O
–	O
2004	O
which	O
provided	O
point-to-point	B-Architecture
connectivity	O
between	O
processor	O
and	O
peripheral	O
devices	O
are	O
sometimes	O
referred	O
to	O
as	O
fabrics	O
;	O
however	O
,	O
they	O
lack	O
features	O
such	O
as	O
a	O
message-passing	B-Architecture
protocol	O
.	O
</s>
<s>
For	O
example	O
,	O
HyperTransport	B-Device
,	O
the	O
computer	O
processor	O
interconnect	B-General_Concept
technology	O
,	O
continues	O
to	O
maintain	O
a	O
processor	B-General_Concept
bus	I-General_Concept
focus	O
even	O
after	O
adopting	O
a	O
higher	O
speed	O
physical	O
layer	O
.	O
</s>
<s>
Similarly	O
,	O
PCI	O
Express	O
is	O
just	O
a	O
serial	O
version	O
of	O
PCI	O
;	O
it	O
adheres	O
to	O
PCI	O
's	O
host/peripheral	O
load/store	O
direct	B-General_Concept
memory	I-General_Concept
access	I-General_Concept
(	O
DMA	O
)	O
-based	O
architecture	O
on	O
top	O
of	O
a	O
serial	O
physical	O
and	O
link	O
layer	O
.	O
</s>
<s>
In	O
the	O
Fibre	B-Architecture
Channel	I-Architecture
Switched	B-Architecture
Fabric	I-Architecture
(	O
FC-SW-6	O
)	O
topology	B-Architecture
,	O
devices	O
are	O
connected	O
to	O
each	O
other	O
through	O
one	O
or	O
more	O
Fibre	B-Architecture
Channel	I-Architecture
switches	I-Architecture
.	O
</s>
<s>
While	O
this	O
topology	B-Architecture
has	O
the	O
best	O
scalability	B-Architecture
of	O
the	O
three	O
FC	O
topologies	B-Architecture
(	O
the	O
other	O
two	O
are	O
Arbitrated	B-Architecture
Loop	I-Architecture
and	O
point-to-point	B-Architecture
)	O
,	O
it	O
is	O
the	O
only	O
one	O
requiring	O
switches	O
,	O
which	O
are	O
costly	O
hardware	O
devices	O
.	O
</s>
<s>
Visibility	O
among	O
devices	O
(	O
called	O
nodes	B-Protocol
)	O
in	O
a	O
fabric	O
is	O
typically	O
controlled	O
with	O
Fibre	B-Architecture
Channel	I-Architecture
zoning	I-Architecture
.	O
</s>
<s>
Multiple	O
switches	O
in	O
a	O
fabric	O
usually	O
form	O
a	O
mesh	B-Architecture
network	I-Architecture
,	O
with	O
devices	O
being	O
on	O
the	O
"	O
edges	O
"	O
(	O
"	O
leaves	O
"	O
)	O
of	O
the	O
mesh	O
.	O
</s>
<s>
Most	O
Fibre	B-Architecture
Channel	I-Architecture
network	O
designs	O
employ	O
two	O
separate	O
fabrics	O
for	O
redundancy	O
.	O
</s>
<s>
The	O
two	O
fabrics	O
share	O
the	O
edge	O
nodes	B-Protocol
(	O
devices	O
)	O
,	O
but	O
are	O
otherwise	O
unconnected	O
.	O
</s>
<s>
One	O
of	O
the	O
advantages	O
of	O
such	O
setup	O
is	O
capability	O
of	O
failover	B-General_Concept
,	O
meaning	O
that	O
in	O
case	O
one	O
link	O
breaks	O
or	O
a	O
fabric	O
goes	O
out	O
of	O
order	O
,	O
datagrams	B-Protocol
can	O
be	O
sent	O
via	O
the	O
second	O
fabric	O
.	O
</s>
<s>
The	O
fabric	O
topology	B-Architecture
allows	O
the	O
connection	O
of	O
up	O
to	O
the	O
theoretical	O
maximum	O
of	O
about	O
16	O
million	O
devices	O
,	O
limited	O
only	O
by	O
the	O
available	O
address	O
space	O
(	O
224	O
)	O
.	O
</s>
