Corporate cell phones

Completely brand new to Asterisk, before I delve in, just wanted to know if someone can tell me if this is possible.
Would like to sign up corporations and have all cell phones under their umbrella go through a Call Through or Call Back service. From what I know so far, Each corporation will be provided with their own DID. After this, I don’t know. I would like the calls to go through a “system” (Astersisk?), that will then ask for the extension of the individual cellular user, and then terminate the call to that user.
I would like to do this for many corporations, utilizing only one computer.
Is this possible?
Your responses and suggestions of hardware/software will be greatly appreciated for this newcomer into the telephony forum.
Any other special considerations, etc?
Thank-You

That’s possible for sure using just Asterisk standard features and only one box, for appropriate suggestions more details are needed or better ask specific questions.

Cheers.

Marco Bruni
www.marcobruni.net

Here are some more specifics.
One of our local cell phone carriers offers a very low price for receiving unlimited calls to and from only one number. I would like to take advantage of this service by allowing corporate customers who have a lot of cell phone users, to offer one number to the public (a DID) this number will then be answered by Asterisk, and prompted with the company name, and ask what extension you would like to be connected to. Then Asterisk (I hope) will do what it does, and terminate the call to the cell phone user. Can all of the cell phone users dial the same number as an outgoing call now, and then asked what number to dial like a call through service, and then have that call terminated as well?
If that is possible, I would like to offer to multi corporations, each with their own greeting system.

I hope this clarifies in more detail.

Thanks for your suggestions/comments

Yes.

This can be done too, just check the called number (did).

As I said before, no needs for special software, Asterisk can do all you need.
The hardware needed depends on the codecs used, if transcoding will be needed and the type of channels (sip, iax, dahdi), search with Google for “Asterisk dimensioning” to have more informations.

Cheers.

Marco Bruni
marcobruni.net