TDM400P -> Mitel SX2000 help needed

Hi Folks,

Just need a few pointers from those in the know.

We have a ‘fully loaded’, read can’t add Pri/Bri ISDN interfaces to it Mitel SX2000 Lite runninh lightwave

I need to interface to this an * box to provide VOIP extensions for our remote users.

Having worked with Mitel’s for a couple of years and used a Mitel Mail with analog integration I had assumed that I could use an * box with a TDM400 in the same way i.e. setup the ONS ports as ‘VoiceMail’ ports and thereby capture CID etc.

Well the TDM400 is ‘almost’ working, I can make an receive calls to / from the * box, the problem I have is that the * box doesn’t detect if the SX i.e. the remote party hangs up the call, although the * side can hangup the call without problem.

The other area that isn’t working is CID, when connected to a regular POTS line CID is captured witthout a problem.

Has anyone attempted this type of integration?

Does anyone have any pointers as to how to configure the TDM400 or the SX? At the moment I have tried KS & LS with UK callerid v23 etc, I’ve also tried US settings without luck.

Any help and assitance would be much appreciated.



Hi Simon

Ok What ons card are you using? as to cleardowns only certain of the clip cards support positive disconects.
I have intergrated ith BRI and Pri and due to the problems with alog I have avoided it. Not to say I wouldnt try if needs must

If you want more info email direct or call fwd 43143


WOW! That was quick!

Thanks Ian,

The ONS card in question is an MC320CD



Ok, No chance of a positive disconnect :frowning: or cli being passed over. There are some options but it depends on options on the switch



Whats the best I can hope for?

If I were to look for another ONS card to allow those two which one would it be?

Thanks for you help.

Hi MC320EB and making sure you have the class/clip option. (refers to UK part no). I do have one here at the moment.


SOLVED (Partially)

Just thought I’d update this thread so that anybody in the future trying to do this can benefit from my partial success.

First off many thanks to Ian, without whom’s help I wouldn’t have got this far.

Ok first off a quick summary of what I wanted to achieve.

I wanted to add ‘VOIP’ extensions to our existing Mitel SX2000 using Asterisk and a TDM400P card with 4 FXO modules as the link between the two.

The extension numbers must be in the same range as our existing ‘standard’ extensions and external DDI must also function.

I did not want to be limited to ‘4’ VOIP extensions i.e. the number of ports on the TDM400 therefore the link should operate like a ‘trunk’ and not just a bunch of extensions.

I am using Asterisk 1.2.5 and Zaptel 1.2.4

Ok on the SX side.

If you don’t already have one create a class of service of type ‘voice mail’

To do this create a new class of service and set the following option :

COV/ONS/E&M Voice Mail Port = YES

Connect the TDM400 to 1 or more ONS extension ports on the SX, for each of these ports set the COS to the number of the Voice Mail class of service as above.

Create a new hunt group of type ‘VoiceMail’ and add all the above extensions to it.

Now for each VOIP extension create a new hunt group using the required extension number e.g. I wanted a VOIP extension with a number of 223 so I created a hunt group 223.

Leave the ‘Hunt Group’ type as Voice.

You will need to add at least 1 extension number otherwise the SX won’t allow you to create the hunt group, use any existing ‘standard extension’ number.

Save the new hunt group.

Re open the newely created hunt group and remove the 1 extension added during creation, save the changes to the now blank group.

Open the ‘Call Rerouting Always Assignment’ form.

Choose an unused number and change the value of DID/TIE/CO/INTERNAL to ‘reroute’, for the directory number enter the number of the Voice Mail hunt group you created previously.

Save your changes and move to the ‘Call Rerouting Assignment’ form, scroll down the list until you find the ‘VOIP’ extension number hunt group you created earlier. Under the Always alternative section assign the reroute always number that you have just configure in the previous step to the DAY/NIGHT1/NIGHT2 options.

The configuration of the SX is now complete.

For additional ‘VOIP’ extensions simply create ‘empty’ hunt groups using the ‘extension number’. Then assign the same Call Rerouting Always value for these new ‘extensions’ in the ‘Call Rerouting assignment’ form as per the very first extension created.

On the Asterisk side.

In your dial plan modify the incoming context used by your TDM400 as follows:

exten => s,1,Answer()
exten => s,n,WaitExten(5)

exten => ,1,Dial(,)

And thats it.

Ok so how does this work?

Well when the VOIP extension is called from a traditional extension or DDI incoming call the SX reroutes the call as per the ‘Call Reroute Always’ setting. I.e. the call is sent to a free line on the TDM400.

As the ‘hunt group’ used is set as ‘VoiceMail’ after the Asterisk box answers the call the SX2000 sends the ‘called’ extension ID using DTMF tones to the Asterisk box, which the WaitExten command picks up and uses to jump in our dial plan.


So what doesn’t work, well with the ONS cards I have the TDM400 doesn’t detect if the SX hangs up the line. As such you will need to ensure you set ‘timeouts’ for every option involving calls ‘from’ the Zap channels.

If a caller from the SX hangs up before the VOIP extensions answers the Asterisk box will not notice and instead will continue to ring the VOIP extension.

Also Calling Line ID is not presented by the SX.

Hope this helps someone in the future.

Many thanks again to Ian, who is investigating an alternate ONS card that might solve the problem of undetected hangups.


Simon Slaytor