[asterisk-users] North American voice BRI - Informal survey

[Tzafrir Cohen]

Hi

On Thu, Jul 05, 2007 at 03:34:38PM +0200, Frank Ochmann wrote:
> List,
> 
> just my two cents here on BRI cards for Asterisk - sorry if the
> following info was posted before/is redundant.
> 
> You will find the following BRI cards for Asterisk. Depending on the
> chipset/Asterisk module they will/will not support NT mode, have
> different numbers of ports, scale well when cards are combined, offer
> PCI/PCIe interfaces, support other protocolls like Q.Sig and so on.
> 
> The most commom (here in Europe) would be:
> 
> Digium B410 - supports NA BRI
> (http://www.digium.com/en/products/hardware/b410p.php)
> 
> Sangoma A500
> (http://sangoma.com/datasheets/A500BRI)
> 
> Junghanns Duo/Quad/OctoBRI
> (http://www.junghanns.net/en/produkte.html)
> 
> BeroNet BN2S0/BN4S0/BN8S0
> (http://www.beronet.com/index.php?option=com_content&task=category&sectionid=5&id=26&Itemid=28&lang=en)
> 
> Sirrix PCI4S0
> (http://www.sirrix.com/content/pages/pci4s0en.htm)
> 
> Dialogic/Eicon DIVA boards
> (www. dialogic.com)
> 
> Other cards: Fritz!Card PCI (http://www.avm.de/en) or their C2/C4 cards,
> and basically clones of the cards mentioned above from China (OpenVox
> et. al). Basically check for the HFC-S chipset (the icon outline of the
> Cologne Cathedral is printed on these chips) on the net.
> 
> All of them work with Asterisk, but settings/combinations with server
> hardware, analogue cards etc. can be an issue, so the easiest way to use
> BRI with Asterisk (for me) is to use a Patton SmartNode.

But this review would not be complete without a short review of the ways
to connect those cards to Asterisk:

There is a deprecated 
* chan_modem_i4l: now deprecated. Interfacing the isdn4linux stack.
  Uses an established kernel interface and hence no out-of-tree kernel
  drivers are needed.

The out of tree Bristuff "patch" (maintained by Junghanns) has 
historically included two ISDN drivers:

* chan_zap: the bristuffed libpri and chan_zap support the extra
  features used in ISDN BRI (e.g: ptmp). 

  Any idea how well, if at all, this works in North America?
  chan_zap in itself supports various ISDN (PRI) signalling methods 
  in the US. So I believe that most of the support should be there.

  Supports basically Cologne HFC-based cards: the Junghanns cards and
  their clones, BRI modules of our Astribank, and many cheap single-port
  PCI card based on the HFC-S chip.

  (No driver is available for USB-based HFC devices. Driver authors are
  welcome. In addition, both the BeroNet and Digium BRI cards are based
  on the same chipset. If one is really interested, one could adjust the
  existing qozap driver for them).

  Also supported, with the help of an extra libpri-like library
  (libgsmat) i the Junghanns GSM adapter, which is presented as a sort
  of digital line with one B channel and one D channel per port.

  Zaptel is not in the mainline kernel, and hence requires an
  out-of-tree kernel stack. Though many of you have it as Asterisk
  likes to have it (the bristuff changes to Zaptel itself are minimal
  and non-disruptive. It mainly adds a bunch of extra drivers. The core
  of its changes are in userspace).

* chan_capi: interfacing with the CAPI kernel interface. While bristuff
  still has a version of it, it was forked aside at some point
  (chan_capi-cm). Surprisingly, the Junghanns page is still the top hit
  on a google search for chan_capi.

  Like chan_modem_i4l above, this on uses an established kernel
  interface and hence requires no extra drivers for standard cards.

  Thus chan_capi is an out-of-tree module (but at least a separate
  module, and not a complete separate Asterisk version). It is mainly
  maintained by Melware.

  It supports the high-end Eicon Diva cards, as well most other cards
  (though with some limitations, IIRC).

  Any idea how well that one works in North America?

* chan_misdn: Mainly maintained by BeroNet. Has become the official ISDN
  channel as of 1.2 . All others require some extra installation:
  Bristuff is an alretnative Asterisk installation at this point,
  chan_capi and chan_visdn are out-of-tree modules, and chan_modem_i4l
  is deprecated.
  
  It uses the mISDN stack the should some day replace isdn4linux. But 
  until then it still requires out-of-tree kernel modules for even the
  basic stack.

  It supports a variety of BRI hardware.

  Any idea how well, if at all, this works in North America?

* chan_visdn: Originally a spin-off of chan_zap, but this is an
  independent ISDN stack. 

  Likewise has its own separate set of kernel-space drivers.

  According to its overview page it only supports euroisdn.


As for Sangoma's card: last time I check, its drivers did not include
support for the A500 card. I'm still not sure what they mean by "support
for Asterisk": which ISDN channel?


Disclaimer: as I have mentioned above our company has some BRI hardware
that was left out of the message I posted to. I still hope you'll find
my message useful.

-- 
               Tzafrir Cohen       
icq#16849755                    jabber:tzafrir at jabber.org
+972-50-7952406           mailto:tzafrir.cohen at xorcom.com       
http://www.xorcom.com  iax:guest at local.xorcom.com/tzafrir