[asterisk-dev] Virtual Modem Pool

[Brad Silen]

We are looking to deploy thousands of hardware devices connected to the PSTN
which will upload data and download firmware updates using v.90 modems. It
will be deployed to a demographic which does not have Internet access.

We are hoping to avoid setting up an old fashion modem pool, POTs or T1-PRI,
and hope to access the PSTN through a SIP Trunk or IAX2.  This solution
would be both cost effective and scale to handle peak loads; For example,
when a firmware download is required.

Ideally we would like our application servers to send/receive using TCP/IP
sockets with the virtual modems which are being driven by the VOIP
infrastructure.

The network might look like:

Device <--> POTs <--> VOIP Gateway <--> IAX2 <--> ??? <--> Clear Text on
TCP/IP Socket

Solve for ???

Has anyone used Asterisk in this way?

Is there any reason why the VOIP Gateway (SIP Trunk or IAX2) data path would
prevent modem communication?

Is there any similar solution terminating a v.34 connection (aka Fax)?  A
Fax solution would verify the ability to send data via the VOIP pathway and
offer sample code as a starting point.

Would we extend the Asterisk concept of an "extension"?  For example,
instead of forwarding the traffic to a SIP Phone the virtual modem would be
an "extension" which converts the data stream to ASCII clear text.  Or, what
would be the suggested architecture choice in Asterisk?

Note, I am very open to better, easier, or more clever solutions.

If there are service providers offering this type of virtual modem pool
please have your shameless commerce division email me directly.  I suggest
they not respond to the list since I am concerned it would violate the rules
of this list.  I have not been able to find a solution and expect to
contribute.