<s>
ALCAP	B-Protocol
(	O
"	O
Access	O
Link	O
Control	O
Application	O
Part	O
"	O
)	O
within	O
a	O
3rd	B-Architecture
Generation	I-Architecture
Universal	B-Protocol
Mobile	I-Protocol
Telecommunications	I-Protocol
System	I-Protocol
(	O
UMTS	B-Protocol
)	O
network	O
is	O
the	O
control	O
plane	O
protocol	B-Application
for	O
the	O
transport	B-Architecture
layer	I-Architecture
.	O
</s>
<s>
ALCAP	B-Protocol
is	O
defined	O
by	O
3GPP	O
as	O
equivalent	O
of	O
ITU	O
recommendation	O
Q.2630.2	O
.	O
</s>
<s>
Basic	O
functionality	O
of	O
ALCAP	B-Protocol
is	O
multiplexing	O
of	O
different	O
users	O
onto	O
one	O
AAL2	B-Protocol
transmission	O
path	O
using	O
channel	O
IDs	O
(	O
CIDs	O
)	O
.	O
</s>
<s>
It	O
is	O
used	O
in	O
the	O
UMTS	B-Protocol
access	O
network	O
UTRAN	O
along	O
with	O
ATM	O
,	O
while	O
IPBCP	O
is	O
use	O
for	O
IP	O
links	O
in	O
the	O
core	O
of	O
the	O
network	O
.	O
</s>
<s>
ALCAP	B-Protocol
makes	O
it	O
possible	O
for	O
up	O
to	O
248	O
channels	O
to	O
be	O
multiplexed	O
onto	O
one	O
AAL2	B-Protocol
bearer	O
.	O
</s>
<s>
ALCAP	B-Protocol
is	O
the	O
protocol	B-Application
used	O
for	O
control	O
plane	O
of	O
transport	B-Architecture
layer	I-Architecture
UMTS	B-Protocol
in	O
charge	O
of	O
managing	O
and	O
multiplexing	O
users	O
into	O
ATM	O
AAL2	B-Protocol
virtual	O
connections	O
.	O
</s>
<s>
ALCAP	B-Protocol
is	O
specified	O
for	O
Iub	O
,	O
Iur	O
and	O
Iu	O
(	O
circuit	O
switched	O
domain	O
)	O
interfaces	O
.	O
</s>
<s>
This	O
protocol	B-Application
is	O
only	O
used	O
when	O
these	O
interfaces	O
are	O
ATM-based	O
.	O
</s>
<s>
The	O
ITU-T	O
Q.2630.2	O
standard	O
,	O
AAL	B-Protocol
type	I-Protocol
2	I-Protocol
signalling	O
protocol	B-Application
-	O
Capability	O
Set	O
2	O
,	O
is	O
chosen	O
for	O
ALCAP	B-Protocol
protocol	B-Application
.	O
</s>
<s>
For	O
Iub	O
and	O
Iur	O
interfaces	O
,	O
ALCAP	B-Protocol
is	O
specified	O
in	O
3GPP	O
TS	O
25.426	O
.	O
</s>
<s>
For	O
Iu	O
interface	O
,	O
ALCAP	B-Protocol
is	O
specified	O
in	O
3GPP	O
TS	O
25.414	O
.	O
</s>
<s>
SSCOP	O
:	O
the	O
SAAL	O
sublayer	O
that	O
transports	O
ALCAP	B-Protocol
signaling	O
messages	O
.	O
</s>
