<s>
Class-based	O
queuing	O
(	O
CBQ	O
)	O
is	O
a	O
queuing	B-Application
discipline	I-Application
for	O
the	O
network	B-Application
scheduler	I-Application
that	O
allows	O
traffic	O
to	O
share	O
bandwidth	O
equally	O
,	O
after	O
being	O
grouped	O
by	O
classes	O
.	O
</s>
<s>
CBQ	O
divides	O
user	O
traffic	O
into	O
a	O
hierarchy	O
of	O
classes	O
based	O
on	O
any	O
combination	O
of	O
IP	B-Protocol
addresses	O
,	O
protocols	O
and	O
application	O
types	O
.	O
</s>
<s>
Because	O
it	O
operates	O
at	O
the	O
IP	B-Protocol
network	O
layer	O
,	O
CBQ	O
provides	O
the	O
same	O
benefits	O
across	O
any	O
Layer	B-Protocol
2	I-Protocol
technology	O
and	O
is	O
equally	O
effective	O
with	O
any	O
IP	B-Protocol
protocol	I-Protocol
,	O
such	O
as	O
Transmission	B-Protocol
Control	I-Protocol
Protocol	I-Protocol
(	O
TCP	O
)	O
and	O
User	B-Protocol
Datagram	I-Protocol
Protocol	I-Protocol
(	O
UDP	O
)	O
.	O
</s>
<s>
It	O
also	O
operates	O
with	O
any	O
client	O
or	O
server	O
TCP/IP	O
stack	O
variation	O
,	O
since	O
it	O
takes	O
advantage	O
of	O
standard	O
TCP/IP	O
flow	O
control	O
mechanisms	O
to	O
control	O
end-to-end	O
traffic	O
.	O
</s>
<s>
An	O
implementation	O
is	O
available	O
under	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
for	O
the	O
Linux	B-Operating_System
kernel	I-Operating_System
.	O
</s>
