Yesterday, I received a message from Skype stating my voicemail option was expiring and they wanted $20 for voicemail. I believing that Microsoft incorrectly advertised UM for Exchange 20007 standard edition, I decided to look again at Asterisk. Although I am familiar with UNIX, the merging of the Telco and UNIX was going to be a large hill to climb. After I got Asterisk installed on a Red Hat virtual machine, I began setting up the interface between Asterisk with the Audiocodes MP-118. Of course, Asterisk really wanted integration with Digitium FSX/FXO cards. This meant that I would have to dispose of the MP-118 and purchase yet another piece of hardware. This is something that I didn't really want since I had purchased it especially for the UM with Exchange.

Because of this desire, I decided to browse the Microsoft site again. Of course with all Microsoft products, they provide service patches (thank you!). Service patch 1 had been released to the public. Like usual, I went ahead and download the patch and installed it. I ran into problem when installing the patch. The first one was that the NetBIOS name had to be the same as the name used for ehlo/helo. I changed it back to the hostname and the patch continued to install. That is until; it got down to the HUB interface. It failed at this point stating that Forefront was installed and it would prevent it from continuing. So, I had to disable Forefront and restarted the patch. It continued to process on through. Once complete, I re-enabled Forefront and replaced my original EHLO/HELO hostname. I was up and back in business!

Once the patching was complete, I checked my email to make sure that the exchange server was up and operating correctly. When I check my mailbox, it was online and it had voice messages in it. These were old voicemail messages, but they were now delivered. Was I incorrect with Exchange 2007 Standard edition not supporting Unified Messaging? I picked up the phone which was connected to the MP-118 and called a known extension. The attendant picked up the phone and took a message. When I hung up, moments later the message appeared in my email box. This was finally working as I wanted it. I have not disregarded the asterisk solution again and moved back to Exchange 2007 SP1 Standard edition.

Now that voicemail working and delivering messages, I don't have to pay Skype for voicemail. Now when a voicemail is left, I can get it in my inbox, cell phone, or internet. I am very happy! Thank you Microsoft!

I will be continuing this adventure. I was just temporarily postponed for a patch!

Of course, you will have to read the PDF document and follow the directions.  I will try to describe what is happening with the INI file. 

PREFIX = 2,10.15.6.1,*,0,255


The first line is describes what to do with a call when a call comes into the FXO port (or incoming POTS line).  It begins with describing the destination phone prefix.  It is stating what the first number of an extension (i.e. 2).  Next is the IP address of the server (device) that these calls will be routed.  In this case, it is routing it to the IP address of the MP-118 gateway. The asterisks (*) is a wild card which specifies all source phone prefixes.  So if you have multiple FXO ports, you should be able to route each one differently based on the source prefix (or port) it comes into the gateway.  The next number is a zero (0).  This is the profile id of the port.  This is referenced in another page where you can specify the profile of the incoming port.  So if you wanted to route fax lines or Skype Line differently than a POTS line, then you would setup different profiles for each of the incoming lines.   The last line should be the charge code.  Since the allowable numbers are from 1 to 25, this number is disregarded. 

PREFIX = *,10.15.3.207,*,0,255

This is the next line in the ini file.  It describes all other destination number from a source number and where to send this call.  It describes a destination number of anything (*).  It is followed by the IP address of the exchange server.  Next is the source number of anything (*).   Of course, we have the profile ID (0) next and the last item is the charge code (255 which is nothing).  This line states any other number that you want must go to this ip address (which is my exchange server).  This allows going to the auto attendant which is at ext 1000 or the voicemail box at 3000. 

Here are the next two lines:

FWDINFO_0 = 4,2001@10.15.3.207;transport=tcp,20
FWDINFO_1 = 4,2002@10.15.3.207;transport=tcp,20

This is setting up the FSO ports to route to a specific number after a certain amount of time.  The first item is the port name.   FWDINFO_0 is the first FSO port on your box.  FWDINFO_1 is the second port on your box and so on.  It is assigning the forwarding information to the port (=).  The next number specifies what option to assign to the port.  Here are the available options:

0 - Deactivated
1 - On Busy
2 - Unconditional

So now that the DHCP reboot problem was solved, I needed to get the phone actually working.  I poked through each of the screen before changing anything.  This was wise, but still unhelpful.  The reason for this is that there were so many terms that I didn't know and titles that don’t make any sense to me.   Well, that is not entirely true.  I do understand many of the term.  Not just how they are used or what will happen when an option was selected.
 
After about 4 hours of screwing around with the configuration completely up and not knowing which setting was really incorrect?  After this point, I decided to begin trolling the internet on hints on what do it.  I found instructions on how to setup a MP-114 to exchange.  It has the ini file to configure the MP-114, a ps1to configure exchange, and a PDF file to give instruction on what to do with everything. 

Here are the files:

PDF Instructions
ini config for the MP-114
ps1 to configure Exchange

With this, I finally was able to call an extension and have it ring another line.  After about 20 seconds, it would be forwarded to exchange.  Exchange even answered it and asked to leave a message, although I am still having problems with them being forward to my email box.  Some cool features that did work was having my email read, able to delete message, and even send voice messages to other users.  

After the long days waiting for the AudioCodes MP-118 4FXO/4FXS box from EBay, I finally received it in the mail. It came in good condition, so I got another good buy from EBay.  The MP-118 was used in a demo for some call center somewhere.  It normally retails for in the $650 to $800 range, so I was excited to find it as a buy it now for $305 + shipping.  The bid cost was $295, so it wasn't worth it to be out bid and wait another 4 days for it to arrive.   So, I bought it now. 

When I got the device here, I ripped the box open and took inventory of what was in the box.  It came with a CD, manual, power cord, and the MP-118.  First thing I did was pull out the manual and began reading.  Most of the information was very intelligible and it looked like it would be smooth sailing to get this setup.  Boy, I was wrong. 

The MP-118 booted up fine.  Following the manual, there were several ways to connect to the device.  The easiest, and most easily accessible, was through the network.  I first tried to directly connect to it, but it was by default on a different subnet.   I tried several things when a bell rung in my head.  I could do this by phone.  I dug out an old phone from the closet and connected it to one of the FSX ports.  I pick up the receiver and I got a dial tone.  I followed the instructions and typed the ***12345 into the phone and the gateway began to talk to me.  I followed the prompts to change the IP address and netmask and I was on my way, or so I thought. 

The MP-118 had rebooted when I was finished with my call.  I typed the IP into a web browser to pull up the administration website.  The site came up fine, so I logged into the site and began to poke around.  I clicked on a couple of things and the MP-118 rebooted.  I tried to log back in and I was unsuccessful.  I poked around on the network and found that it was on the next higher address.  I went to that and logged in again.  Low and behold, I found, not after too long, that it rebooted again.  This time I noticed the "Fail" light glow red.  This wasn't good, so I tried again.  I began to poke around franticly to figure out what was the problem. Reboot! After about 20 minutes of this, I finally figured out that it was requesting a DHCP address.  For some reason, it would cause an error after a period of time and force the reboot.  Finally, I found the "Enable DHCP" setting and set it to disabled.  I decided that I didn’t like the IP address it landed on, so I changed it and save the settings.  After this point, I have not had any problems with this.  

Now that I got the connectivity setup correctly, I decided to see if I can get&a ...

Now the cost of $650 was a bit much for me to plop down on a learning endeavor.  I better know exactly what I am doing before even think about spending this sort of dough on Audiocodes MP-118.  The first was what does FXS and FXO mean?

Foreign eXchange Subscriber (FXS) and Foreign eXchange Office (FXO) are the names of the two most common interfaces (ports or plugs) found in analog telephony environments.  Analog telephony, also known as Plain Old Telephone Service (POTS), is the service the local phone company typically delivers to your home. Local phone companies deliver POTS from their Central Office (CO) to the subscriber’s premises over a circuit consisting of two copper wires. To increase the distance over which the signal can be transmitted the two wires are twisted together, which also reduces electromagnetic interference. So these two-wire copper cables are commonly known as “twisted pairs.”

FXS - Foreign eXchange Subscriber interface (the plug on the wall) delivers POTS service from the local phone company’s Central Office (CO) and must be connected to subscriber equipment (telephones, modems, and fax machines). In other words an FXS interface points to the subscriber. An FXS interface provides the following primary services to a subscriber device:

* Dial Tone
* Battery Current
* Ring Voltage

You may also see the FXS acronym rendered as Foreign eXchange System.

FXO - Foreign eXchange Office interface (the plug on the phone) receives POTS service, typically from a Central Office of the Public Switched Telephone Network (PSTN). In other words an FXO interface points to the Telco office. An FXO interface provides the following primary service to the Telco network device:
* on-hook/off-hook indication (loop closure)

Because of the characteristics described above, a telecommunications line from an FXO port must connect to an FXS port in order for the connection to work. Similarly, a line from an FXS port must connect to an FXO port in order for the connection to work. When the FXO port on your analog telephone is connected to the FXS port in the wall, you receive (FXS) service from the telephone company – and you hear a dial tone when you pick up the phone.

Common Usage
Within the telephony industry, a device is often referred to by the type of interface it provides
(“your phone is an FXO device”), or even spoken of as being the interface (“your wall plug is
FXS”). Now, continuing our discussion in common usage . . .

What Doesn’t Work
If you connect an FXS device to another FXS device, the connection will not work. Likewise, if you connect an FXO device to another FXO it will not work. So, for example, you can NOT plug a standard analog telephone (FXO) ...

The idea started when I started playing with Skype and VoIP.  VoIP has been a wonderful way to reduce the telephone costs by providing competition.   Through my exploring of this work, I have always dreamed of having a unified messaging solution.  You know where you can receive you voicemail, faxes and email anywhere.  Well through Exchange 2003, I was able to get my email everywhere through my PDA phone.  It works great, but still lacking voice. 

From the start of this site, my initial dream was to provide information on how to develop to the Skype API.  One of the project ideas was to capture voicemail and send it to my email box.  But with the pressures of life, I have not had the time to pursue this endeavor.  So I thought that I hit the jackpot when Microsoft was releasing Exchange 2007 with Unified Messaging.  I had upgraded my Exchange Server to 2007, but this was not the panacea of my VoIP world.  It needed more!  So I began trolling for information. 

What I found out, was Exchange 2007 needed to talk with a VoIP server that could speak SIP (Session Intitation Protocol).    But I didn't have one setup.  I have been keeping my eye on Asterisk, but I hadn't found anybody (none commercial) that connected Asterisk to Exchange.  I has also stumbled across some devices that were Unified Messaging approved.  Now I am thinking that I am going to have to find a device that had to be approved by Microsoft.  This was not what I wanted.  So I began trolling once again. 

Finally, I stumbled across this article.  The title was "Unified Messaging
with Microsoft Exchange Server 2007" written by Farrukh Noman and Suman Kumar Singh.  I found it on the Dell Power solutions website.    On Page 92, I found that all I needed was a VoIP Gateway and in the example was using the Audiocodes MP-118 VoIP Gateway.  This spawned more trolling for information.  

I did a search for Audiocodes MP-118 and I found them for sale on various sites.  The best I could guess was that it was about $650 for the device.  Definitely much cheaper than a PBX and from the mockup in the paper, it would connect to standard FXO and FXS ports.  I didn't know what all this meant, but I have heard the term before although never knew what they meant.  So, my story begins....