Connecting between Callmanager MCS 7800 ,CISCO 2821 AND ERICSSON MD110 PBX

Hello guys;
I need to configure my Cisco 2821 and my Callmanager MCS 7825  to make voice calls bothways from the IP Phones to the analog phones on an Ericsson MD110 pbx. On my Voice gateway Cisco 2821 i have a 2 x 4port FXO module installed. I managed to make the call to be routed directly from the Call manager to the analoge phone but it's just ringing and when you pickup the handset no thing is heared and a busy tone is heared after 3 rings

I need the full configuration for each of the callmanager and the Cisco 2821 and the PBX ericsson MD110
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Can you give me some more information on how these devices are connected?  What is the 2821 FXO plugged into?  The FXO expects to be plugged into a phone LINE, so if you're using this to talk to the Ericsson, you'd likely have to plug it into an analog telephone port.

So, here's what's probably happening..  Since the FXO is supposed to hook to a PHONE LINE (same type as you'd have at home), if you managed to get the Cisco configured to pick up that port, it's going to pick up that port and expect to hear dial-tone.  That's why it needs to be hooked to a telephone port on the alternate system.  

If that's done, then the Cisco will "hear" the dial-tone, and dial the digits that you typed on the phone  (I'm assuming a lot in the Cisco config here, but for the moment, I'll assume it's configured right)..  So, the Cisco dials the number into the Ericcson, which then routes the call to it's extension as if someone with an Ericcson telephone had picked up and dialed the phone.  This is COMPLETELY do-able, and basically a simple config...  However, supporting calls from the Ericsson back to Cisco in this config is not as clean..  What you're expecting is that someone is going to call an extension on the Ericson and generally when you dial a phone number, that phone will ring...  In this case, you're dialing "into" the FXO port of the Cisco.  The Cisco WILL pick up the phone, but unless the ericson is smart enough to then dial the digits for the desired extension on the Cisco, the caller is just going to hear the Cisco's dial-tone, *OR* you could configure the Cisco FXO port for "PLAR" which stands for "Private Line Automatic Ringdown" which is like the "batphone".. As soon as a PLAR port rings, it is picked up, and automatically forwarded to another number...  So, you'd have to configure the FXO to connect an inbound call to a specific extension in that case...

Give me some more detail on what you're really trying to accomplish, and also what version of CCM you're running on the 7825, and maybe we can figure something out..  Does the Ericcson support SIP trunks??

waled1985Author Commented:
well for the moment the situation is as follows:
- the Cisco 2821 router is now connected to the Erricsson PBX via an E1 interface (30 voice channels)
- the calls are running internally bothways between the IP phones and the analog phones
- It is required to use the DID feature to make calls from outside the company to the IP phones

What configuration is required on each of the PBX and the Voice gateway router and the Callmanager to accomplish this

any question about further details is welcomed
I'm not sure I understand what it's not doing for you now..  Unless when you say "It is required to use the DID feature to make calls from outside the company to the IP phones", you mean that you can't get that to work??  I am interpreting that to mean that you figured out that you had to use a DID feature to get a call from outside to route to the IP phones..

I'm going to assume that's what it is - Let me know if I'm mis-reading this..

So, GENERALLY, from the PSTN, you'll get a block of numbers..  Let's say that your phone numbers are coming in from the PSTN and they're giving you 4 digits to the PBX, and that's how the PBX routes to the right extension..  In otherwords, if your extensions are 500-599, and the phone company has assigned you 212-384-6500 through 212-384-6599, they will "send digits" 65xx to your PBX.  Your PBX would then be programmed to drop the first of those 4 digits, and then forward the call to the last 3 numbers as the extension...  That's a basic overview of a SIMPLE scenario..

In your case, the Ericsson PBX has to do this to interface with the PSTN, AND it has to pretend that it's the PSTN to send calls to the Cisco.

I've never configured the ericcson before, so take everything I say about the Ericcson as an assumption and not fact.... BUT..  let's say that in my previous example, you decide that x520 through 529 will be moving to a Cisco phone.  Somehow you need to configure in the Ericcson that calls that come in with digits 652x should be routed to the E1 that goes to the Cisco..  Apparently you've got that route setup, since you can make calls from Ericcson to Cisco manually.. The trick is going to be to have the inbound calls evaluated to decide whether to go to Cisco or not...

A second possibility, which is probably less manageable but may be easier to test..  I dont know your numbering scheme, but let's say that you had to create a new set of dialing rules to connect to the Cisco - Like maybe you made it so that you dial "8xxx" to cause the Erricson to dial the Cisco.  You might have to create extensions (on the Erricson) for all the phones you want to move and then call forward them to 8xxx to force it to go to the Cisco..

One other thing - I found this link:

It's CLOSE to what you want to do..  I assume your version of Call Manager is newer than the one shown, but I can help you with that part of it if you can't figure it out..  What I dont know is the Erricson side..

Let me know if this helps, or if I'm misunderstanding..  Tell me how you have it configured to make calls back and forth now..

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waled1985Author Commented:
first I deeply appologize for being so late as some thing happened to me and kept me off for a long time

secondly I will explain the situation in more and specific way

so forget about my early request for making calls bothways between analoge and IP phones

In my company for any one outside the company to call any one inside he calls 2625+internal no which is 4 digits for example to call my phone directly from outside just call 26253374 and that's is an interpretation for the DID feature

now we have IP phones already calling and receiving both ways from the analog system

these IP phones have the DN 5xxx and we want any one outside the company to call directly these phones just like what happens with the analoge ones

so I hope It's clear now

the PDF didn't  resolve what I mean so I'm waiting
OK - What I think you're asking for is for the DID function to work to get to the Cisco phones..

So, for example, if your Cisco phone is 5123, you want to call 26255123 and have the Cisco phone ring, right?

The telco has to assign the "real" phone numbers...  Do you own the phone number 25255xxx for all of your internal Cisco IP 5xxx phone numbers?  If not, you need to ask the phone company if those numbers are available, and pay for the DIDs.

If you do, and it's STILL not working, then it's a translation problem on the analog PBX..  Let me draw a picture

current analog call:
(outside user dials 2625-3374) - > (telco routes the call to you, and strips all but the last 4 digits) -> (Analog PBX recieves 3374 and looks up phone number) -> (Ring your phone)

This is the way it SHOULD be working now, so if you add your Cisco logic, it should work like this:

(outside user dials 2625-5123) - > (telco routes the call to you, and strips all but the last 4 digits) -> (Analog PBX recieves 5123 and looks up phone number) -> (PBX sends call over tie-line to Cisco) -> (Cisco looks up 4 digit 5123 number) -> (Ring your Cisco IP phone)

THAT should work.. HOWEVER, it also could be that the telco is only sending 3 digits to you  (sometimes called "outpulsing").  If this is the case, then whoever installed the analog PBX changed the logic to prepend the "3" to the phone number recieved, so it works like this:

(outside user dials 2625-3374) - > (telco routes the call to you, and strips all but the last 3 digits) -> (Analog PBX recieves 374 and prepends the 3 and looks up '3374' as the phone number) -> (Ring your phone)

If that's the case, then when you add the Cisco in there, it will break:

(outside user dials 2625-5123) - > (telco routes the call to you, and strips all but the last 3 digits) -> (Analog PBX recieves 123 and prepends '3' because that's what it's always done.  looks up phone number 3123 and finds no match) -> Call Fails - No number 3123.

There are several ways to fix this.  
Your first step is to look at the inbound configuration of your old PBX to see if it's prepending any digits, or stripping any digits (the telco could be sending 5 digits, and you're stripping one to get the 3374)
If you can't get into that config, or dont know how, you can call your telco, and ask them how many digits they're sending you.  If they're only sending 3, then you're going to have a problem,  because somehow your analog phone system is going to have to determine whether to send the call to the Cisco or not, and IT will have to know to prepend the 5 instead of the 3.  If that's the case, your best bet is to switch the Telco to sending 4 digits, and you stop the analog PBX from adding the 3 to the beginning.

Anyway, this is getting complicated  - I think the most likely scenario is that you dont own the DIDs from the phone company.  let me know how that goes, and we'll go from there!



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waled1985Author Commented:
I will contact our PBX support company to reveal the unknown parameters

in conclusion I have came to a result that all the config to be done shall be on the PBX

If that's no true tell me the parts of config to be done on the router and the callmanager and
If you can already make calls between the two PBXs, then the PRI between them seems fine, so unless something in the translation on the PRI router was to be changed to help the digit manipulation, then yes, everthing can be done on the PBX . callmanager..

Let me know if you find any of the answers and need more help!

waled1985Author Commented:
well for the moment i shall accept this result and I will ask for your help directly if you allow me just send me your direct email if this is permittable

thank you & best regards
waled1985Author Commented:
the answer was helping but some parameters still needs to be revealed

Let me know if I can help - You could just add more to this thread and it'll email it, and/or I think there's a PM function on here to use..

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