Using IAS in a dial-out situation

[micheld]

I have the following scenario to solve and Radius (IAS) will be probably the
way to go. Before proceeding, I would like to confirm the approach makes
sense. Am i missing something or something I didn't understood in my readings?

I have operators at a central that will established a PPP connexion with
Device-A in the field (dial-out). Device-A is running an application on
Windows CE. Device-A will also establish a connexion to the central at a
schedule time. The second scenario does not cause a problem. RAS is design to
support dial-in.

1. An operator at the central, through and application running on a Windows
2003, will request a connexion to Device-A. This PPP connexion will be
establish using an IP address. The company routers will forward to the
request to a Remote Access Server (RAS).

2. The RAS will request to the AAA (IAS) service the profile corresponding
to the IP address.

3. The AAA service will fetch the information from AD and then return it to
IAS.

4. The AAA service (IAS) will return the profile to the RAS (Telephone
number, route and authentification information)

5. With the profile information, the RAS will establish a PPP connexion with
Device-A.

6. Device-A will validate the authentification information againt its
internal database.

7. Device-A will complete the PPP connexion with the RAS.

Point 2, 3 and 4 is where I don't fell 100% comformtable.

Any help will be appreciated.
Thanks,
--
Michel