I have a Cisco SPA8000 configured to connect the voip system with 8 extensions. These 8 extensions are transformed into 8 analog lines by SPA8000. The 8 analog lines are connected to an old Mitel SX1000. From the analog phones connected to the Mitel, I can make external calls through Mitel -> SPA8000 -> SIP ... But in reverse direction, the Mitel is not able to pick up the calls of SPA8000.

I am not an expert of Mitel. My question is:

If SPA8000 has an incoming calls, does it need to dial a number (or do something to) to connect to Mitel first (for example, connect to the console and/or auto-attendent before putting the incoming call on Mitel)? Currently the SPA8000 does nothing. I tested using an analog phone connected to SPA8000, if there is a incoming call, the phone does ring, and I can pick it up. But if the SPA8000 is directly connected to Mitel. It seems obvious to me that the Mitel doesn't know there is an incoming call at all.

Your help is appreciated!

What Model of Mitel sx1000 is not a Mitel number, Sx200, 200ICP,sx2000,sx50 ,3300?

SC1000 is a console model

There IS an Mitel SX100 (One Hundred), which is nothing more than 1/2 of an ollldd SX200 Analog. It has a cabinet about the size of a VERY large Microwave cabinet. About 28 X 14 X 14 inches. One shelf with 16(?) slots. The cards are 12 X 12 inches, more or less, just like the 200 analog cards. (Big surprise, they use all the same cards!)

In any case, you've probably got some programming to do, still.

I think I provide inaccurate information in the original post. I will need someone to find out what Mitel system is. I am just remotely working on the integration.

My question still is, is there any specific settings for a cisco ATA (SPA8000) to connect to a Mitel system, and Mitel is able to respond.

A few days ago, the Mitel was connected to a same type of device (CISCO ATA) and worked fine. But once I brought in another CISCO ATA, I can only make outbound calls from Mitel, all the inbound calls are not picked up by MiTel. So I believe there must be something that Mitel doesn't accept the calls from the new ATA. But I am not sure what might cause this. I think the CISCO ATA just sends analog phone calls to Mitel, and reaches the Mitel console. Not sure why it doesn't work for the new ATA.

Brought in? Are you saying you removed the previous ATA and installed a new one? If the previous one was working, why did you replace it? Or are you trying to add more lines? You have to program the new lines into an outbound hunt group, and then direct incoming calls on them to a destination elsewhere in programming.
It would 'seem' that you got the first part done.