<s>
Simple	B-Protocol
Certificate	I-Protocol
Enrollment	I-Protocol
Protocol	I-Protocol
(	O
SCEP	O
)	O
is	O
described	O
by	O
the	O
informational	O
.	O
</s>
<s>
The	O
Simple	B-Protocol
Certificate	I-Protocol
Enrollment	I-Protocol
Protocol	I-Protocol
still	O
is	O
the	O
most	O
popular	O
and	O
widely	O
available	O
certificate	O
enrollment	O
protocol	O
,	O
being	O
used	O
by	O
numerous	O
manufacturers	O
of	O
network	O
equipment	O
and	O
software	O
who	O
are	O
developing	O
simplified	O
means	O
of	O
handling	O
certificates	O
for	O
large-scale	O
implementation	O
to	O
everyday	O
users	O
.	O
</s>
<s>
It	O
is	O
used	O
for	O
example	O
by	O
the	O
Cisco	B-Protocol
IOS	I-Protocol
operating	O
system	O
(	O
even	O
if	O
Cisco	O
is	O
now	O
pushing	O
the	O
slightly	O
more	O
featured	O
EST	B-Protocol
)	O
and	O
iPhones	B-Device
to	O
enroll	O
in	O
enterprises	O
PKI	B-Architecture
.	O
</s>
<s>
Most	O
PKI	B-Architecture
software	O
(	O
specifically	O
RA	O
implementations	O
)	O
supports	O
it	O
,	O
including	O
the	O
Network	O
Device	O
Enrollment	O
Service	O
(	O
NDES	O
)	O
of	O
Active	B-Protocol
Directory	I-Protocol
Certificate	O
Service	O
and	O
Intune	B-Application
.	O
</s>
<s>
A	O
limitation	O
shared	O
by	O
other	O
enrollment	O
protocols	O
based	O
on	O
PKCS	O
#10	O
CSRs	O
,	O
e.g.	O
,	O
EST	B-Protocol
and	O
ACME	B-Protocol
,	O
or	O
even	O
the	O
web-based	O
enrollment	O
workflow	O
of	O
most	O
PKI	B-Architecture
software	O
where	O
the	O
requester	O
starts	O
by	O
generating	O
a	O
key	O
pair	O
and	O
a	O
CSR	O
in	O
PKCS	O
#10	O
format	O
.	O
</s>
<s>
For	O
example	O
ACME	B-Protocol
,	O
which	O
also	O
uses	O
PKCS	O
#10	O
,	O
issues	O
TLS	O
certificates	O
which	O
by	O
definition	O
must	O
be	O
capable	O
of	O
signing	O
for	O
the	O
TLS	O
handshake	O
.	O
</s>
<s>
SCEP	O
was	O
designed	O
by	O
Verisign	O
for	O
Cisco	O
as	O
a	O
lean	O
alternative	O
to	O
Certificate	B-Protocol
Management	I-Protocol
over	I-Protocol
CMS	I-Protocol
(	O
CMC	O
)	O
and	O
the	O
very	O
powerful	O
but	O
also	O
rather	O
bulky	O
Certificate	B-Protocol
Management	I-Protocol
Protocol	I-Protocol
(	O
CMP	O
)	O
.	O
</s>
<s>
In	O
around	O
2010	O
,	O
Cisco	O
suspended	O
work	O
on	O
SCEP	O
and	O
developed	O
EST	B-Protocol
instead	O
.	O
</s>
