Need competent help with my voip idea , anyone?

[andreab]

I have four offices.
3 in rome and one in milan. i have a tollfree number and so all the calls arrives at this number. and we manually tell the people to call back.

This is very annoying.

I see that there are a lot of linksys products for voip over lan, my idea is to buy some of this products to do the following.

Wire my analog exchange to one voip product and configure that voip gateway to call another voip gateway in another office without using voip providers , only myadsl connection.
I would like also to have routing capabilities like
"press 1 to choose office number 1"
"press 2 to choose office number 2"
to route the calss to different voip gateways.

did i explain my needs?

I'm sorry for my english.

[rizsher]

One way i can think of achieving this is by setting up an Asterisk server. (have a look at www.nerdvittles.com). What you would need is:

a) A Decently spec'd PC, I would think a 2 Ghz Pentium 4 with 1 GB Ram should be able to cope with 6-7 simultaneous calls very easily

b) Enough DSL bandwidth to support the maximum number of simultaneous calls you expect.

c) Either an FXO card (Digium/Sangoma etc), or an ATA with a PSTN line interface (SPA3102 for eg). Keep in mind the ATA route has generally not been that great when it comes ot PSTN-VoIP interfacing and most people would opt for a hardware FXO card, specially for a business setup. These cards aren't very cheap, configuration can be tricky, but if you do go this way, make sure the PC you choose isn't based a compact half height casing cos as far as I'm aware, FXO cards only come in full height PCI card format. You could completey go away from this issue by porting you incoming number to VoIP (if that option is available in Italy), or choosng a new incoming number with a VoiP service provider

d) As many Linksys/Grandstream/etc ATA or SIP Phones as you want to create extensions at your various offices. Each of these devices will register as a "remote" extension to your main Asterisk server, therebly allowing free calls between different offices, and also the xfer of outside calls from main office to others, individual VoiceMail boxes for each extension, options ot email voicemails etc etc etc... Asterisk is almost limitless when it comes to features, and..best of all, its ALL FREE

Once you have all this, the setup is very easy to achieve. www.nerdvittles.com has detailed instrucitons on setting up a server, complete with digital auto-attendent that would intecept an incoming call and play back the "Press 1 for xxxx 2 for yyyy" message, and then based on the caller's choice, forward the call to the remote extension.

Readup on Astirisk and PiaF (PaBX in a Flash)... its easier than it would first appear, and there is plenty of support available at Voxilla, and a LOT more over at Nerdvittles.com and FreePBX.org

[andreab]

mmmm
maybe i didn't explain...
i want to keep normal numbers.
i want to redirect a call to internal phone of my office ( i can do that now with my analog switch board )
i want to take the analog voice in that internal phone-line and transform that to voip packet.

i want to route those packet automatically to another ip

i want to make the inverse trasformation to the other office.

is more clear now?