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<DIV><SPAN class=659244913-07072005><FONT face="Futura Bk" size=2>I'm having a
problem getting Asterisk to talk to Cable and Wireless PRIs in the UK.
After a lot of looking at bits on the wire and looking at the carrier switch, it
seems that the carrier switch is seeing an "unintentional loopback" condition
and taking the PRA out of service.</FONT></SPAN></DIV>
<DIV><SPAN class=659244913-07072005><FONT face="Futura Bk"
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=659244913-07072005><FONT face="Futura Bk" size=2>This occurs
when bit Sa5 (in frames without the frame alignment signal) is set to 0 by the
TE. In the original ETSI PRI Layer 1 specification (ETS 300
011) there was obscurity about what bits Sa4 through Sa8 should be set to
by the TE, however in rev 2 of the specification there is a note (Note 4 to
Table 3) which specifies that Sa4 through Sa8 should be set to ONE by a
TE.</FONT></SPAN></DIV>
<DIV><SPAN class=659244913-07072005><FONT face="Futura Bk"
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=659244913-07072005><FONT face="Futura Bk" size=2>I'm not sure
if looking after framing at this level is looked after by libpri, zaptel or the
specific card driver. I'm guessing it's one of libpri or zaptel, since
these links used to work just fine with older versions of the CVS tree (like
from 2005-04-28). I've also tried this with both a Sangoma AFT104 and a
Digium TE110P with the same problems.</FONT></SPAN></DIV>
<DIV><SPAN class=659244913-07072005><FONT face="Futura Bk"
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=659244913-07072005><FONT face="Futura Bk"
size=2>Cheers</FONT></SPAN></DIV>
<DIV><SPAN class=659244913-07072005><FONT face="Futura Bk"
size=2>Mick</FONT></SPAN></DIV></BODY></HTML>