I have searched through the forums here and on many other Asterisk-based forums and believe I have my deployment plan ready, but I wanted to get some feedback prior to making my purchases.
Our organization has a Legacy PBX (Teltronics Cerato SE) system connected to a T1/PRI from Windstream. The CPE provided by Windstream is an Adtran 624 which is connected to the Legacy PBX via the Adtran’s DSX-1 port to one of the the Cerato’s two PRI (T1) ports. Due to our existing contract and direction from Management, we have to stay with Windstream andI am locked into staying with the T1/PRI connection and cannot switch to a SIP or other provider right now.
My deployment plan is to install a FreePBX machine as a gateway that will run both the Legacy PBX and a new IP-based PBX side-by-side in a configuration that is similar to the following diagram:
My setup will replace the Digium G200 hardware with A Dell PowerEdge 1950 that has a Digium TE205P 2-span card with EC module.
The plan is to setup the new infrastructure and gradually migrate all the users off the Legacy PBX to the new IP/PBX system. Hopefully, the users and Management will see the increased reliability and functionality of the new IP/PBX, which will facilitate the migration process.
What I am looking for here is any advice / critiques of my deployment plan as well as feedback for inprovements / refinements and whether I am overlooking anything.
I would suggest that you use the Dell as a “PassThrough” of the T1, the Network facing side using pri_cpe signalling the legacy side, pri_net, and ensure you derive timing from the network.
If you want to use Asterisk as your gateway then:-
should give you a very solid starting point. Get the simple call passthrough working then add Atreisk/FreePBX features as you feel comfortable, a common problem to surmount is who will handle the voicemails in a unified fashion, which mean you will need to find out to turn lights on and off on the legacy box, and have those legacy extensions properly respond to pressing the button, also examples given in the link I posted. Also consider that the equipment you are replacing might or might not be more reliable than the Dell/Asterisk system, consider redundancy for everything.
I was wondering if the scenario you recommend was even an option. It seemed to be a duplication of efforts to have one machine as the gateway and then another, similar machine hosting the new IP/PBX system. If I understand you correctly, I can setup the Dell to pass the T1 through to the Legacy PBX system as well as host the new IP/PBX. I know I am repeating myself a little, but I want to make sure I am absolutely clear.
Now, as far as the hardware is concerned, am I correct in selecting a TE205P as my interface/interconnect? I have the opportunity to procure one at little to no cost, as compared to one of the newer Digium products, in order to do my proof of concept and start the project rolling. Once the system is up and running and I have complete buy-in, I will be able to budget for and procure newer hardware.
Regarding the voicemail functionality, that is not a major consideration for me. The organization consists of about 10 staff that are in the office regularly and another 15 that work in the field. Most rely on their mobile solutions for communication, as the environment of the current proprietary legacy solution is not a very good at integrating communication functions. To be honest, if the proof-of-concept goes as I expect it to, adoption/migration to the FreePBX infrastructure will go very quickly and most, if not all, users will integrate and rely on the expanded feature sets / functionality.
I still have many TE405/205 in use, no failures ever there. (they are real Digium TE205’s not clones, is yours ? ) the only problem I see is lack of redundancy but many folks can accept occasional down time if it saves them money.
I am the wrong guy to ask that I have an aversion to everything M$ it will be always expensive, rarely working for long without pouring more money in, is never standards compliant, in general that vendor is a PITA in every way, look at Kamailio instead.
Hehe, I think we are all a long way away from a “Unified Communication infrastructure”, SIP is a good start but Asterisk only touches the tip of that iceberg yet. Again look at Kamailio, it is not just a VOIP proxy and doesn’t require expensive add-ons to do lots of other SIP proxy stuff.
If you happen to be a Cisco shop and have a 2800 or other router with voice capability consider putting PRI interfaces in it and using it as the gateway.
Cisco Dial Peer functionality is very rich. The Cisco could act as the gateway to the different services.
It also is far more enterprise class than the Digium or any of the “prosumer” type gateways. I have never been impressed with the older Digium Tigerjet based hardware like the TE-105.
For other folks reading the thread the newer generation Digium cards and the Sangoma are much better. However as a Cisco guy with deep knowledge of the product and the secondary market I would never use a card when I can buy and enterprise class external gateway for less.
If you don’t know any router IOS and have not worked on a modular hardware platform it is best not to go down this route.
A dell poweredge is server not a router. You may be running router software on it. That’s a heck of a lot of power for routing/NAT/access list/content filtration etc.
Yeah, I have gone through it a bunch of times. The problem is that I can’t make heads nor tails of the information provided from Windstream about the PRI…
There are really only three choices needed If you are in NANP land you will almost certainly be framing with B8ZS/ESF using PRI-CPE timing and NATIONAL signalling, You will have B channels in slots 1-23 and a D channel on slot 24. These are conveniently the defaults for DAHDI PRI’s.
I am at a stand-still here. When I dial in to the main number, I’m getting a message that the number is out of service and I am getting the RED/LFA alarm on the span that is connected to the legacy PBX. If I disconnect/bypass the FreePBX box and hook the legacy PBX back into the Adtran CPE that is provided by Windstream, everything resolves.
