Full circle

Some of you may know that 15 years ago, when we started, we sold mobile phones and ISDN PABXs. One of the most popular products we did was a package of an ISDN2 + 8 extension phone system, wiring and sockets and cable clips so that you could wire up a small home or office. It was so popular we even got boxes made for shipping the kit to people, and we sold hundreds of them...

Later, we started selling Network Alchemy PABXs which were a larger scale, and we sold systems with ISDN30 lines and hundreds of phones in large offices. We kitted out call centres. One of the small models was even on display in the science museum, thanks to us. We did a load of support software and sold boxes to do voicemail and call logging and billing. We led the way in integrating the phone systems and management tools. We even moved on to selling Splicecom phone systems.

I always wanted to make my own ISDN PABX though - as no system quite did what I wanted in terms of features. There was always something that was a compromise.

We gradually moved over in to Internet stuff over a few years, partly because the Network Alchemy did ISDN "dial-up" Internet access as a standard feature.

Since then we have started doing VoIP services, so you can have a phone on your desk with a phone number connected via the Internet. These systems are tricky when people have NAT and they are not playing IPv6 very well yet, so this is not ideal. But it works and we have thousands of VoIP customers. But this is not quite the same as the old "phone systems" we used to sell.

As of today we have a FireBrick acting as an Internet gateway and SIP gateway. Yes, much work to do but it sort of hit me that it is finally my chance to make a PABX.

What you probably don't realise is that I first started playing with PABXs on a 1 line 5 extension analogue system which I had at home and at my parents (IIRC) over 20 years ago. There was a 2 line analogue system as well, I seem to recall.

The design is very much a "per packet" system, and the FireBrick has no hard disk, so handling calls is fine but not IVR, voicemail or call recording. However, it can easily link to services "in the cloud" for such things and stand alone software on a local PC/server as well.

Ironically, a lot of features and "state" are now in the phones. e.g. Do not disturb, call forward, divert on no reply, etc. But the call server needs to handle ring groups and call queuing systems. It can handle things like "wrap up time". With the SNOM phone we can do busy lamp fields as well. And one of my favourite features "call steal" which is so much easier than transferring calls.

Of course the FireBrick can easily provide data on calls, queue times, and so on.

So, my plan is to make the FB2500/FB2700 provide a good set of PABX features. Obviously we like the SNOM phones, but it will be nice to integrate nicely with other makes of phone too. We will start using it ourselves in our offices when we are ready, which will mean it will get new features quickly.

I am also inclined to make it a standard feature in the base model. This is not definite yet, and maybe you will need a "fully loaded" brick for all of the features. To be decided.

Of course it will integrate well with our services. We will be able to have a small office, even if using NAT, with phones on desks and real phone numbers through us. We can have iPads L2TP in to the office LAN, and have mobile phone SIMs connect as office PABX extensions. I think it will be very cool.

P.S. please don't tell me that a multi decade long ambition to make a PABX from scratch is somehow "sad".


  1. Cybergear Gold bought from A&A many years ago is still working well. Need to work hard to be as reliable. It just works year after year. Even if FB2x00 was as reliable, internet connections aren't.

  2. How will the firebrick (if at all) handle the non-pbx stuff?
    i.e. I have SNOM phones with one registration to my Quadro PBX but more independant registrations to Draytel, Iptel, as well as dedicated AAISP numbers. Will the Firebrick help those sort of connections in a way that allows the Firebrick to be piggy in the middle between phone and registrar in such a way as to allow the phones to be on private IP addresses and not have to employ NAT?

  3. Yeah, I still have my CGG as well :-)

    I called the Rev, or Adrian as he was known then, when I left the RAF to setup my own business and I ordered ISDN2.

    I saw his Advert in Demon's Newsletter.

    When I called I got a voicemail box (he was probably still st work elsewhere!) so I left my name and requested a call back.

    Adrian did call back but by then I was out (ships in the night) so I dialed again.

    Adrian was out again but this time the announcement said "Hello Simon Faulkner We are not able to take your call etc..."

    When it read my name back I just HAD to have one so I ordered.

    Sadly, many years down the line that functionality is not baked into Asterisk - I really ought to write an AGI script...

    Good luck RevK, I look forward to having a "proper" PABX again.


    PS - Please can it do caller name announcement?

  4. @alexb - Clearly you have never been to Singapore

  5. @simonf - you can do all of that in Asterisk without an AGI script.

  6. @NAB - oooh, that would be nice - can you elaborate?

  7. @SimonF - I'm 'NAB' on #a&a-asterisk (irc.z.je) - please PM me.

  8. Revk, I still have one of those Emmerich ISDN PBXs in my drawer. I scrapped my CGG a few years back when I migrated to voip and cut off my ISDN line. Sigh. Those were the days!

  9. We're still running one of those Alchemy PABXs at work - still works absolutely perfectly even after this long! The voicemail server's a bit tricky though - Red Hat 7.2 and the documentation's vanished...

    1. Yeh, we'll need a new voice-mail server. Won't be hard I am sure.


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