<s>
Passport	B-Protocol
Carrier	I-Protocol
Release	I-Protocol
(	O
PCR	O
)	O
is	O
a	O
version	O
of	O
the	O
Passport	B-Protocol
Switch	O
(	O
now	O
Multiservice	B-Protocol
Switch	I-Protocol
)	O
software	O
designed	O
to	O
run	O
in	O
telecommunications	O
carrier	O
environments	O
.	O
</s>
<s>
After	O
the	O
sale	O
in	O
2009	O
of	O
most	O
Nortel	O
's	O
assets	O
,	O
the	O
passport	B-Protocol
SW	O
is	O
still	O
used	O
in	O
several	O
products	O
of	O
Alcatel-Lucent	O
,	O
Ericsson	O
and	O
Kapsch	O
.	O
</s>
<s>
The	O
passport	B-Protocol
products	O
are	O
now	O
part	O
of	O
Ericsson	O
's	O
PPX	O
products	O
under	O
IP	B-Protocol
Networking	O
.	O
</s>
<s>
Internally	O
,	O
PCR	O
is	O
largely	O
built	O
up	O
of	O
custom	O
applications	O
on	O
top	O
of	O
a	O
VxWorks	B-Operating_System
kernel	O
.	O
</s>
<s>
A	O
benefit	O
of	O
the	O
software	O
is	O
that	O
it	O
is	O
completely	O
modular	B-Architecture
and	O
can	O
load	O
components	O
to	O
Passport	B-Protocol
control	O
processors	O
(	O
CPs	O
)	O
and	O
function	O
processors	O
(	O
FPs	O
)	O
on	O
an	O
as-needed	O
basis	O
.	O
</s>
<s>
PCR	O
consists	O
of	O
a	O
custom	O
OAM	B-Architecture
interface	O
that	O
is	O
highly	O
object	B-Language
oriented	I-Language
.	O
</s>
<s>
This	O
reflects	O
the	O
modular	B-Architecture
nature	O
of	O
the	O
operating	O
system	O
.	O
</s>
<s>
The	O
core	O
component	O
when	O
provisioning	O
IP	B-Protocol
networks	O
is	O
the	O
Virtual	O
Router	O
(	O
however	O
,	O
a	O
Passport	B-Protocol
switch	O
can	O
act	O
in	O
more	O
than	O
IP	B-Protocol
environments	O
)	O
.	O
</s>
<s>
It	O
is	O
best	O
to	O
consider	O
the	O
environment	O
in	O
which	O
provisioning	O
occurs	O
to	O
be	O
object	B-Language
oriented	I-Language
,	O
in	O
the	O
sense	O
that	O
the	O
behaviour	O
of	O
the	O
router	O
is	O
defined	O
based	O
on	O
which	O
objects	O
are	O
instantiated	O
and	O
how	O
they	O
are	O
related	O
.	O
</s>
<s>
Note	O
that	O
there	O
is	O
a	O
change	O
in	O
this	O
paradigm	O
noticeable	O
in	O
recent	O
releases	O
of	O
PCR	O
--	O
MPLS	B-Protocol
,	O
for	O
example	O
,	O
now	O
resides	O
on	O
an	O
object	O
called	O
simply	O
a	O
Router	O
with	O
built-in	O
IP	B-Protocol
features	O
.	O
</s>
<s>
Unfortunately	O
,	O
at	O
this	O
time	O
the	O
OAM	B-Architecture
interface	O
is	O
unable	O
to	O
select	O
which	O
components	O
are	O
to	O
be	O
loaded	O
on	O
the	O
fly	O
.	O
</s>
<s>
For	O
example	O
,	O
if	O
Multi-link	O
Point-to-Point	B-Protocol
Protocol	I-Protocol
(	O
PPP	O
)	O
is	O
a	O
required	O
feature	O
,	O
before	O
this	O
feature	O
can	O
be	O
used	O
the	O
CP	O
and	O
the	O
FP	O
hosting	O
the	O
MLPPP	O
interface	O
must	O
have	O
the	O
mlppp	O
feature	O
loaded	O
.	O
</s>
<s>
As	O
well	O
,	O
the	O
vast	O
array	O
of	O
objects	O
available	O
to	O
an	O
operator	O
can	O
be	O
daunting	O
,	O
especially	O
for	O
an	O
individual	O
starting	O
out	O
with	O
Nortel	O
Passport	B-Protocol
switches	O
for	O
the	O
first	O
time	O
.	O
</s>
