<s>
In	O
near	O
field	O
communications	O
the	O
NFC	O
Forum	O
Signature	B-Protocol
Record	I-Protocol
Type	I-Protocol
Definition	I-Protocol
(	O
RTD	O
)	O
is	O
a	O
security	O
protocol	O
used	O
to	O
protect	O
the	O
integrity	O
and	O
authenticity	O
of	O
NDEF	O
(	O
NFC	O
Data	O
Exchange	O
Format	O
)	O
Messages	O
.	O
</s>
<s>
Signing	O
certificates	O
are	O
obtained	O
from	O
third	O
party	O
Certificate	B-Architecture
Authorities	I-Architecture
and	O
are	O
governed	O
by	O
the	O
NFC	O
Forum	O
Signature	O
RTD	O
Certificate	O
Policy	O
.	O
</s>
<s>
An	O
author	O
obtains	O
a	O
signing	O
certificate	O
from	O
a	O
valid	O
certificate	B-Architecture
authority	I-Architecture
.	O
</s>
<s>
The	O
security	O
of	O
the	O
system	O
is	O
tied	O
to	O
a	O
certificate	B-Architecture
authority	I-Architecture
and	O
the	O
associated	O
Certificate	O
Chain	O
.	O
</s>
<s>
The	O
NFC	O
Forum	O
Signature	O
RTD	O
Certificate	O
Policy	O
defines	O
the	O
policies	O
under	O
which	O
certificate	B-Architecture
authorities	I-Architecture
can	O
operate	O
in	O
the	O
context	O
of	O
NFC	O
.	O
</s>
<s>
This	O
separation	O
is	O
important	O
for	O
the	O
security	O
of	O
the	O
system	O
just	O
as	O
web	O
browser	O
certificates	O
are	O
separated	O
from	O
web	O
server	O
certificates	O
in	O
TLS	B-Protocol
.	O
</s>
