<s>
SerDes	B-Protocol
Framer	I-Protocol
Interface	I-Protocol
is	O
a	O
standard	O
for	O
telecommunications	O
abbreviated	O
as	O
SFI	O
.	O
</s>
<s>
SFI-4	B-Protocol
or	O
SerDes	B-Protocol
Framer	I-Protocol
Interface	I-Protocol
Level	O
4	O
,	O
a	O
standardized	O
Electrical	O
Interface	O
by	O
the	O
Optical	O
Internetworking	O
Forum	O
(	O
OIF	O
)	O
for	O
connecting	O
a	O
synchronous	B-Protocol
optical	I-Protocol
networking	I-Protocol
(	O
SONET	B-Protocol
)	O
framer	O
component	O
to	O
an	O
optical	O
serializer/deserializer	O
(	O
SerDes	O
)	O
for	O
Optical	B-Protocol
Carrier	I-Protocol
transmission	I-Protocol
rate	I-Protocol
OC-192	O
interfaces	O
at	O
about	O
10	O
Gigabits	O
per	O
second	O
.	O
</s>
<s>
SFI-5	B-Protocol
or	O
SerDes	B-Protocol
Framer	I-Protocol
Interface	I-Protocol
Level	I-Protocol
5	I-Protocol
,	O
a	O
standardized	O
Electrical	O
Interface	O
by	O
the	O
OIF	O
for	O
connecting	O
a	O
SONET	B-Protocol
Framer	O
component	O
to	O
an	O
optical	O
SerDes	O
for	O
OC-768	O
,	O
about	O
40	O
Gbit/s	O
.	O
</s>
