<s>
Worldwide	B-Protocol
Industrial	I-Protocol
Telemetry	I-Protocol
Standards	I-Protocol
(	O
WITS	O
)	O
is	O
a	O
suite	O
of	O
communications	O
protocols	O
designed	O
for	O
use	O
within	O
the	O
public	O
utility	O
industry	O
between	O
components	O
of	O
a	O
SCADA	O
system	O
.	O
</s>
<s>
It	O
was	O
developed	O
for	O
communications	O
between	O
a	O
WITS	O
Master	O
Station	O
and	O
its	O
remotely	O
connected	O
WITS	O
Field	O
Devices	O
(	O
for	O
example	O
,	O
Remote	B-Device
Telemetry	I-Device
Units	I-Device
)	O
.	O
</s>
<s>
WITS	O
maintains	O
two	O
protocols	O
,	O
WITS-DNP3	O
and	O
WITS-IoT	O
.	O
</s>
<s>
WITS-DNP3	O
is	O
a	O
DNP3	B-Protocol
protocol	I-Protocol
based	O
protocol	O
primarily	O
used	O
for	O
larger	O
'	O
always-on	O
'	O
utility	O
assets	O
.	O
</s>
<s>
WITS-DNP3	O
is	O
very	O
well	O
suited	O
to	O
traditional	O
SCADA	O
Telemetry	O
control	O
operations	O
.	O
</s>
<s>
WITS-DNP3	O
is	O
based	O
on	O
the	O
DNP3	B-Protocol
protocol	I-Protocol
level2+	O
,	O
and	O
uses	O
DNP3	B-Protocol
’s	O
generic	O
protocol	O
extension	O
mechanism	O
to	O
define	O
and	O
provide	O
the	O
additional	O
functionality	O
required	O
by	O
water	O
industry	O
users	O
.	O
</s>
<s>
WITS-DNP3	O
provides	O
Secure	O
Authentication	O
between	O
Master	O
and	O
Field	O
Device	O
and	O
uses	O
device	O
vendor	O
supplied	O
Configuration	O
Applications	O
for	O
limited	O
plug	B-Device
and	I-Device
play	I-Device
functions	O
.	O
</s>
<s>
WITS-IoT	O
is	O
a	O
JSON	B-General_Concept
based	O
application	B-Application
layer	I-Application
protocol	O
designed	O
for	O
very	O
large	O
numbers	O
of	O
smaller	O
devices	O
which	O
may	O
be	O
online	O
only	O
for	O
brief	O
periods	O
.	O
</s>
<s>
WITS-IoT	O
provides	O
for	O
robust	O
security	O
using	O
industry	O
standard	O
protocols	O
,	O
enjoys	O
wide	O
and	O
easy	O
availability	O
of	O
its	O
protocol	O
stack	O
and	O
adds	O
full	O
plug	B-Device
and	I-Device
play	I-Device
to	O
WITS	O
for	O
the	O
first	O
time	O
.	O
</s>
<s>
The	O
characteristics	O
and	O
capabilities	O
of	O
a	O
particular	O
WITS-DNP3	O
Field	O
Device	O
are	O
defined	O
in	O
a	O
‘	O
Device	O
Profile’	O
,	O
which	O
is	O
in	O
XML	B-Protocol
format	O
.	O
</s>
<s>
This	O
'	O
device	O
profile	O
 '	O
is	O
read	O
into	O
the	O
WITS-DNP3	O
Master	O
Station	O
and	O
used	O
to	O
limit	O
what	O
a	O
user	O
can	O
do	O
to	O
that	O
particular	O
Field	O
Device	O
.	O
</s>
<s>
WITS-DNP3	O
provides	O
Master	O
Stations	O
with	O
the	O
ability	O
to	O
incrementally	O
change	O
the	O
configuration	O
of	O
Field	O
Devices	O
.	O
</s>
<s>
This	O
is	O
done	O
using	O
DNP3	B-Protocol
file	O
transfer	O
to	O
send	O
incremental	O
configuration	O
updates	O
to	O
a	O
Field	O
Device	O
.	O
</s>
<s>
WITS-DNP3	O
defines	O
seven	O
DNP3	B-Protocol
'	O
Data	O
Sets	O
 '	O
for	O
Field	O
Devices	O
to	O
report	O
data	O
to	O
a	O
Master	O
Station	O
and	O
for	O
a	O
Master	O
Station	O
to	O
control	O
a	O
Field	O
Device	O
.	O
</s>
<s>
WITS-DNP3	O
Field	O
Devices	O
can	O
record	O
local	O
data	O
log	O
files	O
.	O
</s>
<s>
The	O
logs	O
are	O
retrieved	O
by	O
means	O
of	O
DNP3	B-Protocol
file	O
transfer	O
.	O
</s>
<s>
WITS-IoT	O
provides	O
,	O
as	O
a	O
minimum	O
,	O
the	O
same	O
base	O
functionality	O
as	O
WITS-DNP3	O
.	O
</s>
<s>
WITS-IoT	O
takes	O
the	O
WITS-DNP3	O
protocol	O
definition	O
and	O
replaces	O
DNP3	B-Protocol
with	O
JSON	B-General_Concept
structures	O
and	O
a	O
new	O
communications	O
life-cycle	O
description	O
.	O
</s>
<s>
WITS-DNP3	O
devices	O
are	O
'	O
accredited	O
 '	O
in	O
one	O
of	O
two	O
forms	O
:	O
</s>
