<s>
A	O
T-interface	B-Protocol
or	O
T	O
reference	O
point	O
is	O
used	O
for	O
basic	B-Protocol
rate	I-Protocol
access	I-Protocol
in	O
an	O
Integrated	B-Protocol
Services	I-Protocol
Digital	I-Protocol
Network	I-Protocol
(	O
ISDN	B-Protocol
)	O
environment	O
.	O
</s>
<s>
It	O
is	O
a	O
User	O
–	O
network	O
interface	O
reference	O
point	O
that	O
is	O
characterized	O
by	O
a	O
four-wire	O
,	O
144	O
kbit/s	O
(	O
2B+D	B-Protocol
)	O
user	O
rate	O
.	O
</s>
<s>
Other	O
characteristics	O
of	O
a	O
T-interface	B-Protocol
are	O
:	O
</s>
<s>
The	O
T	B-Protocol
interface	I-Protocol
is	O
electrically	O
equivalent	O
to	O
the	O
S	B-Protocol
interface	I-Protocol
,	O
and	O
the	O
two	O
are	O
jointly	O
referred	O
to	O
as	O
the	O
S/T	O
interface	O
.	O
</s>
