<s>
H.245	B-Application
is	O
a	O
control	O
channel	O
protocol	O
used	O
with[in]	O
e.g.	O
</s>
<s>
H.323	B-Protocol
and	O
H.324	O
communication	O
sessions	O
,	O
and	O
involves	O
the	O
line	O
transmission	O
of	O
non-telephone	O
signals	O
.	O
</s>
<s>
It	O
also	O
offers	O
the	O
possibility	O
to	O
be	O
tunneled	O
within	O
H.225.0	B-Protocol
call	O
signaling	O
messages	O
.	O
</s>
<s>
This	O
eases	O
firewall	B-Application
traversing	O
.	O
</s>
<s>
H.245	B-Application
is	O
capable	O
of	O
conveying	O
information	O
needed	O
for	O
multimedia	O
communication	O
,	O
such	O
as	O
encryption	O
,	O
flow	O
control	O
,	O
jitter	O
management	O
,	O
preference	O
requests	O
,	O
as	O
well	O
as	O
the	O
opening	O
and	O
closing	O
of	O
logical	O
channels	O
used	O
to	O
carry	O
media	O
streams	O
.	O
</s>
<s>
It	O
also	O
defines	O
separate	O
send	O
and	O
receive	O
capabilities	O
and	O
the	O
means	O
to	O
send	O
these	O
details	O
to	O
other	O
devices	O
that	O
support	O
H.323	B-Protocol
.	O
</s>
<s>
One	O
major	O
drawback	O
within	O
the	O
initial	O
version	O
of	O
H.323	B-Protocol
was	O
the	O
lengthy	O
,	O
four-way	O
H.245	B-Application
protocol	O
handshake	B-Protocol
required	O
during	O
the	O
opening	O
up	O
of	O
the	O
logical	O
channels	O
of	O
a	O
telephony	O
session	O
.	O
</s>
<s>
Later	O
versions	O
of	O
H.323	B-Protocol
introduced	O
the	O
Fast	O
Connect	O
procedure	O
,	O
using	O
the	O
fastStart	O
element	O
of	O
an	O
H.225.0	B-Protocol
message	O
.	O
</s>
<s>
Fast	O
Connect	O
brought	O
the	O
negotiation	O
down	O
to	O
a	O
two-way	O
handshake	B-Protocol
.	O
</s>
<s>
Another	O
recommendation	O
,	O
H.460.6	O
,	O
Extended	O
Fast	O
Connect	O
Feature	O
,	O
exists	O
that	O
defines	O
a	O
one-way	O
handshake	B-Protocol
.	O
</s>
