[Asterisk-Dev] VoIP and Asterisk

[Antony Stone]

On Thursday 09 December 2004 12:56, Haroon.Ghaus at abacus-global.com wrote:

> Hi
>
> I want to use Asterisk as a VoIP solution.
>
> The clients will use my solution to talk to each other while being online.
> The VoIP will be routed between he client using Asterisk. One other
> functionality provided by asterisk would be to convert normal telephony
> (PSTN) voice to VoIP. This will be used to route PSTN calls to the clients.
>
> My questions are
>
> 1) Is such a solution framework possible?

To quote from the Asterisk webpage at http://www.asterisk.org:

"What Is Asterisk?

Asterisk is a complete PBX in software. It runs on Linux and provides all of 
the features you would expect from a PBX and more. Asterisk does voice over 
IP in three protocols, and can interoperate with almost all standards-based 
telephony equipment using relatively inexpensive hardware.

Asterisk needs no additional hardware for Voice over IP.  For interconnection 
with digital and analog telephony equipment, Asterisk supports a number of 
hardware devices, most notably all of the hardware manufactured by Asterisk's 
sponsors, Digium™."

So, I think it's safe to say "Yes, what you want is possible."

> 2) How much effort would be required to build the client application that
> will be used by the client to make calls to online user or receive VoIP
> calls from asterisk (converted from PSTN voice).

Do you mean a softphone?   Check out Kphone, linphone, or just Google for "SIP 
soft phone".

> 3) What technology should I employ to build the application?

Whatever you're most comfortable building applications in?

> 4) Do I need to build some API for asterisk to, or I just need to configure
> Asterisk to make all this possible?

Just configure it - see the Asterisk docs for details.   Asterisk will connect 
to your PSTN socket through an FXO or ISDN card, and the soft phones will 
connect using a standard protocol such as SIP.

Note, by the way, that the quality of calls through Soft Phones is very 
unlikely to be as good as you can get with a proper SIP telephone.

Regards,

Antony.

-- 
One tequila, two tequila, three tequila, floor.