[Freeswitch-users] need help getting ISDN talking to Cisco 3845

John Wehle john at feith.com
Wed Apr 8 15:19:00 PDT 2009

> Okay, a few things. First off, the wanpipe2.conf file has a booboo.

Don't think so.

> This line is WRONG:
> TDMV_DCHAN      = 0

Not exactly.  My understanding is you can use either:

  wanpipeX.conf: TDMV_DCHAN = 0
  zaptel.conf: dchan = 24 (or in our case 48 since it's the second span)

which means use zaptel to handle the d-channel hdlc or

  wanpipeX.conf: TDMV_DCHAN = 24
  zaptel.conf: hardhdlc = 24 (or in our case 48 since it's the second span)

which means use wanpipe to handle the d-channel hdlc assuming the
wanpipe driver has the necessary support (wanpipe on my platform

> Also, I recommend changing this line:
> wbg1 = wanpipe2, , TDM_VOICE, Comment
> To this:
> wbg1 = wanpipe2, , TDM_VOICE_API, Comment

The sangoma voice API interface isn't available on my platform
and shouldn't be necessary when using zaptel.

> assuming that this is what you want then you will need to use
> ozmod_libpri because the default OpenZAP PRI stack does not
> currently support being the network side.

Are you sure?  Openzap appears to contain implementations for
both NT and TE.  The configuration file supports specifying
either user or network for the mode.  Is the NT support
currently nonfunctional?

I had tried configuring the Cisco as the NT with similar

> I don't see where timing is specified

It's the same T1 which was being used for RBS between
FreeSWITCH and the Cisco so that timing (etc) should
be okay.  No errors are showing up at the physical
level and the Cisco reports Layer 1 as active.

The trace on the Cisco seems to show Layer 2 coming up
(timestamps 22:53:44.264 through 22:54:21.760), then
there's a long pause during which no Receive Ready
frames are received from FreeSWITCH.  At this point
the Cisco gets unhappy and marks Layer 2 as down.

If nothing obvious comes to anyone's mind, then I'll
simply need to trace through the FreeSWITCH ISDN code
and see what's going on.

-- John
|   Feith Systems  |   Voice: 1-215-646-8000  |  Email: john at feith.com  |
|    John Wehle    |     Fax: 1-215-540-5495  |                         |

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