<s>
MPLS	B-Application
VPN	I-Application
is	O
a	O
family	O
of	O
methods	O
for	O
using	O
Multiprotocol	B-Protocol
Label	I-Protocol
Switching	I-Protocol
(	O
MPLS	B-Protocol
)	O
to	O
create	O
virtual	B-Application
private	I-Application
networks	I-Application
(	O
VPNs	B-Application
)	O
.	O
</s>
<s>
MPLS	B-Application
VPN	I-Application
is	O
a	O
flexible	O
method	O
to	O
transport	O
and	O
route	O
several	O
types	O
of	O
network	O
traffic	O
using	O
an	O
MPLS	B-Protocol
backbone	O
.	O
</s>
<s>
There	O
are	O
three	O
types	O
of	O
MPLS	B-Application
VPNs	I-Application
deployed	O
in	O
networks	O
today	O
:	O
</s>
<s>
Point-to-point	O
MPLS	B-Application
VPNs	I-Application
employ	O
VLL	O
(	O
virtual	B-Protocol
leased	I-Protocol
lines	I-Protocol
)	O
for	O
providing	O
Layer	O
2	O
point-to-point	O
connectivity	O
between	O
two	O
sites	O
.	O
</s>
<s>
Ethernet	O
,	O
TDM	B-Protocol
,	O
and	O
ATM	O
frames	O
can	O
be	O
encapsulated	O
within	O
these	O
VLLs	O
.	O
</s>
<s>
Some	O
examples	O
of	O
how	O
point-to-point	O
VPNs	B-Application
might	O
be	O
used	O
by	O
utilities	O
include	O
:	O
</s>
<s>
forwarding	O
non-routed	O
DNP3	B-Protocol
traffic	O
across	O
the	O
backbone	O
network	O
to	O
the	O
SCADA	O
master	O
controller	O
.	O
</s>
<s>
Layer	B-General_Concept
2	I-General_Concept
MPLS	I-General_Concept
VPNs	I-General_Concept
,	O
or	O
VPLS	O
(	O
virtual	O
private	O
LAN	O
service	O
)	O
,	O
offers	O
a	O
“	O
switch	O
in	O
the	O
cloud	O
”	O
style	O
service	O
.	O
</s>
<s>
L2	O
VPNs	B-Application
are	O
typically	O
used	O
to	O
route	O
voice	O
,	O
video	O
,	O
and	O
AMI	O
traffic	O
between	O
substation	O
and	O
data	O
center	O
locations	O
.	O
</s>
<s>
Layer	O
3	O
,	O
or	O
VPRN	O
(	O
virtual	O
private	O
routed	O
network	O
)	O
,	O
utilizes	O
layer	O
3	O
VRF	O
(	O
VPN/virtual	O
routing	O
and	O
forwarding	O
)	O
to	O
segment	B-Protocol
routing	I-Protocol
tables	O
for	O
each	O
customer	O
utilizing	O
the	O
service	O
.	O
</s>
<s>
Multiprotocol	B-Protocol
BGP	I-Protocol
(	O
MP-BGP	B-Protocol
)	O
is	O
required	O
in	O
the	O
cloud	O
to	O
utilize	O
the	O
service	O
,	O
which	O
increases	O
complexity	O
of	O
design	O
and	O
implementation	O
.	O
</s>
<s>
L3	O
VPNs	B-Application
are	O
typically	O
not	O
deployed	O
on	O
utility	O
networks	O
due	O
to	O
their	O
complexity	O
;	O
however	O
,	O
a	O
L3	O
VPN	B-Application
could	O
be	O
used	O
to	O
route	O
traffic	O
between	O
corporate	O
or	O
datacenter	O
locations	O
.	O
</s>
