<s>
Transport	B-Protocol
Layer	I-Protocol
Security	I-Protocol
Secure	I-Protocol
Remote	I-Protocol
Password	I-Protocol
(	O
TLS-SRP	B-Protocol
)	O
ciphersuites	O
are	O
a	O
set	O
of	O
cryptographic	B-Protocol
protocols	I-Protocol
that	O
provide	O
secure	O
communication	O
based	O
on	O
passwords	O
,	O
using	O
an	O
SRP	B-Protocol
password-authenticated	B-Protocol
key	I-Protocol
exchange	I-Protocol
.	O
</s>
<s>
There	O
are	O
two	O
classes	O
of	O
TLS-SRP	B-Protocol
ciphersuites	O
:	O
The	O
first	O
class	O
of	O
cipher	O
suites	O
uses	O
only	O
SRP	B-Protocol
authentication	O
.	O
</s>
<s>
The	O
second	O
class	O
uses	O
SRP	B-Protocol
authentication	O
and	O
public	O
key	O
certificates	O
together	O
for	O
added	O
security	O
.	O
</s>
<s>
Usually	O
,	O
TLS	B-Protocol
uses	O
only	O
public	O
key	O
certificates	O
for	O
authentication	O
.	O
</s>
<s>
TLS-SRP	B-Protocol
uses	O
a	O
value	O
derived	O
from	O
a	O
password	O
(	O
the	O
SRP	B-Protocol
verifier	O
)	O
and	O
a	O
salt	O
,	O
shared	O
in	O
advance	O
among	O
the	O
communicating	O
parties	O
,	O
to	O
establish	O
a	O
TLS	B-Protocol
connection	O
.	O
</s>
<s>
There	O
are	O
several	O
possible	O
reasons	O
one	O
may	O
choose	O
to	O
use	O
TLS-SRP	B-Protocol
:	O
</s>
<s>
Using	O
password-based	O
authentication	O
does	O
not	O
require	O
reliance	O
on	O
certificate	B-Architecture
authorities	I-Architecture
.	O
</s>
<s>
TLS-SRP	B-Protocol
provides	O
mutual	O
authentication	O
(	O
the	O
client	O
and	O
server	O
both	O
authenticate	O
each	O
other	O
)	O
,	O
while	O
TLS	B-Protocol
with	O
server	O
certificates	O
only	O
authenticates	O
the	O
server	O
to	O
the	O
client	O
.	O
</s>
<s>
TLS-SRP	B-Protocol
is	O
implemented	O
in	O
GnuTLS	B-Application
,	O
OpenSSL	O
as	O
of	O
release	O
1.0.1	O
,	O
Apache	O
mod_gnutls	O
and	O
mod_ssl	O
,	O
cURL	B-Language
,	O
TLS	B-Protocol
Lite	O
SecureBlackbox	O
and	O
wolfSSL	B-Protocol
.	O
</s>
