[Asterisk-Users] Re: time to build an open phone?

Bill Schultz bill at alaskafax.com
Fri Dec 26 12:26:36 MST 2003

	ACES - Asterisk Communications Endpoint System
{the following could be used by any IP-PBX but the name pays homage to Mark Spencer and friends who 
cannot be lauded enough for their fine work}

As you read this it will be obvious I am not a professional engineer but I do have enough knowledge 
to be fairly certain what I'm proposing is feasible from not only an engineering, but production 
cost and perhaps most importantly, marketing standpoint. 

An open phone is a great idea but as soon as you "get physical" you add a quantity issue that 
doesn't exist in software.  Multiply this for keypads, handsets, bells, etc. etc. etc. and you have 
a lot of work but more importantly NO ONE has built a phone that can simultaneously be brain-dead 
simple to operate for one person yet offer the advanced user whatever  functionality they might 
want.  You will never solve that issue as long as you have a keypad of any kind.

So you end up with what started this open-phone thread in the first place...  a plethora of IP, 
analog or digital phones with a dizzying array (or lack thereof) of bells and whistles all trying 
to achieve a balance between quality, ease of use and functionality which will sell enough units to 
make their manufacturing and distribution profitable.  In this environment you will always have at 
the low end manufacturers competing on price and inevitably that results in quality issues.  Right 
now it's Grandstream but next year it'll be someone else at a $30 price point and the same issues 
will apply all over again.

I've never seen stats, but it's probably a safe assumption that the majority of IP phones are 
sitting next to a PC and the additional expense has been incurred because "people want a phone that 
looks and works like a phone".  That's certainly been my experience far outweighing any technical 
issues with quality or reliability of a PC-softphone.  In every market I can think of with the 
possible exception of hospitality I think ACES could be successfully sold a substantial number of 
times even though it does not "look like a phone" because it affords a much better way to resolve 
the conflict between ease of use and functionality.  For the unconvinced, a more elaborate version 
could include the obligatory keypad and cosmetic plastic but I would submit that the ability to 
pick up a handset and place a call by saying "call Pat" alone would "sell" most potential customers 
on learning how to operate a two position switch on a device that doesn't have a conventional 
keypad.  At it's simplest, to use the phone you need to know that position A is used to hangup and 
dial by saying "dial 1-800-555-1212" (or whatever number you want called) and position b is used to 

ACES has three components and for simplicity of description I won't go into VERY cool extensions to 
these components for conferencing and/or duplication of the typical 2,3 or 4 line analog phone 
features.  It also assumes a LAN environment again only for simplicity of initial description.  
There's no reason that an ACES Call control server couldn't support  multiple, geographically 
dispersed Asterisk servers.

The heart of this concept is use of text-to-speech to replace keypad functions.  I cannot emphasize 
enough how acutely aware I am of the HUGE resistance users will have to buying something without a 
keypad but bear with me and I hope you'll agree that this has enough "sex appeal" to overcome this 
historically undefeated resistance.  Each "phone is two complete analog/IP circuits defined as:
Talk - a subset of what Asterisk uses now not requiring any of the control functions
TTSControl - moving control functions currently handled by DTMF over to a text-to-speech engine 
located on ACES component 3 described below.  The TTS engine would be capable of translating most 
peoples voices when they speak the word "call" and the ten digits required to place a call.  The 
"phones"(ACES component 2 described below) would simultaneously be user-specific so individual 
users could train their personal library to recognize them when they are "logged in" at that phone 
to place calls by saying "call Pat", etc. etc. etc. and of course to receive calls.

ACES Component 1
EM unit-Ear and Mouth piece, this is a headset or handset with a two position switch and a 4 
conductor jack that plugs into the IP unit(ACES component 2).  FOr prototyping two typical monaural 
PC headsets into a 2.5mm switchbox would do fine.  Switch position one connects the 1st mike and 
earpiece to the 2 "talk" pins on the Talk/TTSControl port on the IP unit and Switch position two 
connects the 2nd mike and earpiece to the 2 "ttsControl" pins on the Talk/TTSControl port on the IP 
unit.  Obviously production handsets/headsets would have only one earpiece/mike with the switch 
changing the connection from one pair of pins to the other.

ACES Component 2
IP unit - a black box containing 5 physical interfaces:
LCD for callerID/outbound calling number verification
Ethernet port 1 - the IP unit gets two IP addresses, one for "talk" and one for "ttscontrol" so 
appropriate hub/switch circuitry would be behind it  One codec connects the first IP address to the 
2 "talk" pins on the Talk/TTSControl port and the other IP address is connected by a second codec 
to the 2 "ttsControl" pins on the Talk/TTSControl port.  If one codec can be used for both, great 
but I believe to be marketable the speed of placing or receiving a phone call has to be equal to or 
faster than the standard POTS-analog equivalent.  The "talk" IP address interfaces with Asterisk 
and the "ttscontrol" IP interfaces with the Call control service described in the next section.
Ethernet port 2 - pass-through port this one works just like existing 2 port IPphones to connect 
your PC, etc.  but the physical design would permit additional modules to be snapped on to add 
functionality similar to 2,3,4 line analog phones later.
Ringer port - inbound call notification 
Talk/TTSControl port - connects to EM unit above
It is significant to note that the IP unit requires no DTMF capability whatsoever.  Smarter people 
than me can determine whether SIP/IAX/H323 or whatever works.  Additionally I see no reason an 
802.11x version could not be easily developed to achieve whatever mix of "corded" and "cordless" 
phones you wanted.

ACES Component 3
Call control service - obviously this could be part of asterisk but scalability issues probably 
make it better implemented as a separate service.  In a SOHO environment it would run as a service 
on the same box as Asterisk.  Larger environments would have a dedicated "Call control server".

So, in summary ACES is a system that offers enough advantages over existing IP phones to convince 
most users to try it without a keypad.  Could even be just what Asterisk needs to take it 
mainstream.  The only thing you'd have to "manufacture" would be the IP unit and I would think the 
elimination of earpiece, mike, DTMF and other components coupled with the fact that one SKU could 
be designed regardless of whether you wanted basic or advanced functionality make the open-source 
engineering that much more feasible.

I'm guessing that Digium would be the logical vendor for ACES Component 2 since unlike existing IP 
phones one SKU would be as universal as the FXS cards they now sell.  ACES component 2 could easily 
be homebuilt in handset or headset form from existing manufacturing and 3 would be GPL open-source 

Of course, I could always be wrong :-)


More information about the asterisk-users mailing list