<s>
In	O
computing	O
,	O
Self-certifying	B-Application
File	I-Application
System	I-Application
(	O
SFS	O
)	O
is	O
a	O
global	O
and	O
decentralized	O
,	O
distributed	B-Protocol
file	I-Protocol
system	I-Protocol
for	O
Unix-like	B-Operating_System
operating	I-Operating_System
systems	I-Operating_System
,	O
while	O
also	O
providing	O
transparent	O
encryption	O
of	O
communications	O
as	O
well	O
as	O
authentication	O
.	O
</s>
<s>
It	O
aims	O
to	O
be	O
the	O
universal	O
distributed	B-Protocol
file	I-Protocol
system	I-Protocol
by	O
providing	O
uniform	O
access	O
to	O
any	O
available	O
server	O
,	O
however	O
,	O
the	O
usefulness	O
of	O
SFS	O
is	O
limited	O
by	O
the	O
low	O
deployment	O
of	O
SFS	O
clients	O
.	O
</s>
<s>
The	O
SFS	O
client	B-Protocol
daemon	B-Operating_System
implements	O
the	O
Sun	O
's	O
Network	B-Protocol
File	I-Protocol
System	I-Protocol
(	O
NFS	O
)	O
protocol	O
for	O
communicating	O
with	O
the	O
operating	B-General_Concept
system	I-General_Concept
,	O
and	O
thus	O
can	O
work	O
on	O
any	O
operating	B-General_Concept
system	I-General_Concept
that	O
supports	O
NFS	O
,	O
including	O
Windows	B-Application
.	O
</s>
<s>
The	O
client	B-Protocol
manages	O
connections	O
to	O
remote	B-Application
file	I-Application
systems	I-Application
as	O
necessary	O
,	O
acting	O
as	O
a	O
kind	O
of	O
protocol	O
translation	O
layer	O
.	O
</s>
<s>
The	O
SFS	O
server	O
works	O
similarly	O
to	O
other	O
distributed	B-Protocol
file	I-Protocol
system	I-Protocol
servers	O
,	O
by	O
exposing	O
an	O
existing	O
disk	B-Application
file	I-Application
system	I-Application
over	O
the	O
network	O
,	O
over	O
the	O
specific	O
SFS	O
protocol	O
.	O
</s>
<s>
On	O
Unix-like	B-Operating_System
systems	I-Operating_System
,	O
SFS	O
file	B-Application
systems	I-Application
can	O
usually	O
be	O
found	O
at	O
.	O
</s>
<s>
When	O
an	O
SFS	O
file	B-Application
system	I-Application
is	O
first	O
accessed	O
through	O
this	O
path	O
,	O
a	O
connection	O
to	O
the	O
server	O
is	O
made	O
and	O
the	O
directory	O
is	O
created	O
(	O
"	O
automounted	O
"	O
)	O
.	O
</s>
<s>
The	O
primary	O
motivation	O
behind	O
the	O
file	B-Application
system	I-Application
is	O
to	O
address	O
the	O
shortcomings	O
of	O
hardwired	O
,	O
administratively	O
configured	O
distributed	B-Protocol
file	I-Protocol
systems	I-Protocol
in	O
larger	O
organizations	O
,	O
and	O
various	O
remote	O
file	O
transfer	O
protocols	O
.	O
</s>
<s>
For	O
example	O
,	O
with	O
SFS	O
,	O
one	O
could	O
store	O
all	O
their	O
files	O
on	O
a	O
single	O
remote	O
server	O
,	O
and	O
access	O
the	O
same	O
files	O
securely	O
and	O
transparently	O
from	O
any	O
location	O
as	O
if	O
they	O
were	O
stored	O
locally	O
,	O
without	O
any	O
special	O
privileges	O
or	O
administrative	O
cooperation	O
(	O
other	O
than	O
running	O
the	O
SFS	O
client	B-Protocol
daemon	B-Operating_System
)	O
.	O
</s>
<s>
Available	O
file	B-Application
systems	I-Application
will	O
be	O
found	O
at	O
the	O
same	O
path	O
regardless	O
of	O
physical	O
location	O
,	O
and	O
are	O
implicitly	O
authenticated	O
by	O
their	O
path	O
names	O
as	O
they	O
include	O
the	O
public-key	B-Algorithm
fingerprint	I-Algorithm
of	O
the	O
server	O
(	O
hence	O
why	O
it	O
is	O
called	O
"	O
self-certifying	O
"	O
)	O
.	O
</s>
<s>
In	O
addition	O
to	O
the	O
new	O
perspective	O
,	O
SFS	O
also	O
addresses	O
some	O
commonly	O
raised	O
limitations	O
of	O
other	O
distributed	B-Protocol
file	I-Protocol
systems	I-Protocol
.	O
</s>
<s>
For	O
example	O
,	O
NFS	O
and	O
SMB	B-Operating_System
clients	O
have	O
to	O
rely	O
on	O
the	O
server	O
for	O
file	B-Application
system	I-Application
security	O
policies	O
,	O
and	O
NFS	O
servers	O
have	O
to	O
rely	O
on	O
the	O
client	B-Protocol
computer	I-Protocol
for	O
authentication	O
.	O
</s>
<s>
The	O
NFS	O
and	O
SMB	B-Operating_System
protocols	I-Operating_System
also	O
do	O
not	O
by	O
themselves	O
provide	O
confidentiality	O
(	O
encryption	O
)	O
or	O
tamper	O
resistance	O
from	O
other	O
computers	O
on	O
the	O
network	O
,	O
without	O
encapsulation	O
layers	O
such	O
as	O
IPsec	B-Protocol
.	O
</s>
<s>
Unlike	O
Coda	B-Application
and	O
AFS	B-Application
,	O
SFS	O
does	O
not	O
provide	O
local	O
caching	B-General_Concept
of	O
remote	O
files	O
and	O
thus	O
is	O
more	O
dependent	O
on	O
network	O
reliability	O
,	O
latency	O
and	O
bandwidth	O
.	O
</s>
