[Asterisk-Users] problems with TDM400P

[Eric Wieling]

On Wed, 2004-06-02 at 00:33, Wim Kerkhoff wrote:
> Following problems have been observed, and are preventing us from
> dumping our existing Nortel Merdian PBX:
> 
> 1. echo at beginning of call for several seconds, even with various
> combinations of echocancel and echotraining in zapata.conf

Echo is miserable to try to fix.  Newer zaptel CVS checkouts have a tool
called "zttest"  What are the results of running zttest?  Unbalanced
lines can cause echo, both IRQ sharing, IDE DMA, framebuffer, and
graphics (as well as crappy motherboards) can introduce latency on the
PCI bus and cause echo.

> 2. even though multiple incoming lines are connected, only the first ZAP 
> channel is picking up. So if
> one line is in use, nobody else can call in even though there are other
> lines free. When in debug mode (-gcvvv) nothing is showing up that 
> there's another call coming in.

This is not a general problem.  It sounds like you are not using group=
in your zapata.conf to put the TDM ports into a hunt group.

> 3. channels don't always hang up properly - HookState shows as offhook
> for quite some time.

Sounds like something isn't providing far end disconnect supervision.

> 4. Asterisk Zap channels don't see an incoming call until 2 rings after
> the existing Nortel PBX sees it. Both people calling in and people 
> answering don't like that.

You don't have Caller*ID on your lines, but Asterisk is configured to
use (and waiting for) Caller*ID.  See the usecallerid= and callerid=
options.

-- 
          Eric Wieling * BTEL Consulting * 504-899-1387 x2111
"In a related story, the IRS has recently ruled that the cost of Windows
upgrades can NOT be deducted as a gambling loss."