<s>
In	O
computer	B-General_Concept
science	I-General_Concept
,	O
robustness	B-Application
is	O
the	O
ability	O
of	O
a	O
computer	O
system	O
to	O
cope	O
with	O
errors	B-Error_Name
during	O
execution	B-General_Concept
and	O
cope	O
with	O
erroneous	O
input	O
.	O
</s>
<s>
Robustness	B-Application
can	O
encompass	O
many	O
areas	O
of	O
computer	B-General_Concept
science	I-General_Concept
,	O
such	O
as	O
robust	B-Application
programming	I-Application
,	O
robust	B-Error_Name
machine	I-Error_Name
learning	I-Error_Name
,	O
and	O
Robust	B-Protocol
Security	I-Protocol
Network	I-Protocol
.	O
</s>
<s>
Formal	O
techniques	O
,	O
such	O
as	O
fuzz	O
testing	O
,	O
are	O
essential	O
to	O
showing	O
robustness	B-Application
since	O
this	O
type	O
of	O
testing	O
involves	O
invalid	O
or	O
unexpected	O
inputs	O
.	O
</s>
<s>
Alternatively	O
,	O
fault	O
injection	O
can	O
be	O
used	O
to	O
test	O
robustness	B-Application
.	O
</s>
<s>
Various	O
commercial	O
products	O
perform	O
robustness	B-Application
testing	O
of	O
software	O
analysis	O
.	O
</s>
<s>
Regardless	O
,	O
complex	O
systems	O
should	O
still	O
handle	O
any	O
errors	B-Error_Name
encountered	O
gracefully	O
.	O
</s>
<s>
When	O
applying	O
the	O
principle	O
of	O
redundancy	O
to	O
computer	B-General_Concept
science	I-General_Concept
,	O
blindly	O
adding	O
code	O
is	O
not	O
suggested	O
.	O
</s>
<s>
Blindly	O
adding	O
code	O
introduces	O
more	O
errors	B-Error_Name
,	O
makes	O
the	O
system	O
more	O
complex	O
,	O
and	O
renders	O
it	O
harder	O
to	O
understand	O
.	O
</s>
<s>
The	O
new	O
code	O
must	O
instead	O
possess	O
equivalent	O
functionality	O
,	O
so	O
that	O
if	O
a	O
function	O
is	O
broken	O
,	O
another	O
providing	O
the	O
same	O
function	O
can	O
replace	O
it	O
,	O
using	O
manual	O
or	O
automated	O
software	B-General_Concept
diversity	I-General_Concept
.	O
</s>
<s>
Currently	O
,	O
computer	B-General_Concept
science	I-General_Concept
practices	O
do	O
not	O
focus	O
on	O
building	O
robust	O
systems	O
.	O
</s>
<s>
Rather	O
,	O
they	O
tend	O
to	O
focus	O
on	O
scalability	B-Architecture
and	O
efficiency	B-General_Concept
.	O
</s>
<s>
One	O
of	O
the	O
main	O
reasons	O
why	O
there	O
is	O
no	O
focus	O
on	O
robustness	B-Application
today	O
is	O
because	O
it	O
is	O
hard	O
to	O
do	O
in	O
a	O
general	O
way	O
.	O
</s>
<s>
Robust	B-Application
programming	I-Application
is	O
a	O
style	O
of	O
programming	O
that	O
focuses	O
on	O
handling	O
unexpected	O
termination	O
and	O
unexpected	O
actions	O
.	O
</s>
<s>
It	O
requires	O
code	O
to	O
handle	O
these	O
terminations	O
and	O
actions	O
gracefully	O
by	O
displaying	O
accurate	O
and	O
unambiguous	O
error	B-Error_Name
messages	I-Error_Name
.	O
</s>
<s>
These	O
error	B-Error_Name
messages	I-Error_Name
allow	O
the	O
user	O
to	O
more	O
easily	O
debug	O
the	O
program	O
.	O
</s>
<s>
As	O
a	O
consequence	O
,	O
the	O
programmer	O
returns	O
to	O
the	O
user	O
an	O
unambiguous	O
,	O
intuitive	O
error	B-Error_Name
message	I-Error_Name
that	O
does	O
not	O
require	O
looking	O
up	O
error	O
codes	O
.	O
</s>
<s>
The	O
error	B-Error_Name
message	I-Error_Name
should	O
try	O
to	O
be	O
as	O
accurate	O
as	O
possible	O
without	O
being	O
misleading	O
to	O
the	O
user	O
,	O
so	O
that	O
the	O
problem	O
can	O
be	O
fixed	O
with	O
ease	O
.	O
</s>
<s>
Dangerous	O
implements	O
Users	O
should	O
not	O
gain	O
access	O
to	O
libraries	B-Library
,	O
data	B-General_Concept
structures	I-General_Concept
,	O
or	O
pointers	O
to	O
data	B-General_Concept
structures	I-General_Concept
.	O
</s>
<s>
When	O
such	O
interfaces	B-Application
are	O
correctly	O
built	O
,	O
users	O
use	O
them	O
without	O
finding	O
loopholes	O
to	O
modify	O
the	O
interface	O
.	O
</s>
<s>
Robust	B-Error_Name
machine	I-Error_Name
learning	I-Error_Name
typically	O
refers	O
to	O
the	O
robustness	B-Application
of	O
machine	O
learning	O
algorithms	O
.	O
</s>
<s>
Recently	O
,	O
consistently	O
with	O
their	O
rise	O
in	O
popularity	O
,	O
there	O
has	O
been	O
an	O
increasing	O
interest	O
in	O
the	O
robustness	B-Application
of	O
neural	O
networks	O
.	O
</s>
<s>
In	O
a	O
sense	O
,	O
robustness	B-Application
in	O
network	O
design	O
is	O
broad	O
just	O
like	O
robustness	B-Application
in	O
software	O
design	O
because	O
of	O
the	O
vast	O
possibilities	O
of	O
changes	O
or	O
inputs	O
.	O
</s>
<s>
There	O
exists	O
algorithms	O
that	O
tolerate	O
errors	B-Error_Name
in	O
the	O
input	O
.	O
</s>
