[Astlinux-users] IAX protocol IE accessibility

[<ast...@el...>]

I have an odd question, related to some ideas I had about provisioning
setups.


Is there an easy way to expose the IE (information elements) in IAX
communications?

The reason I ask is that I want to be able to extract the service
identifier IE from a client contacting Asterisk.

The bad idea I have is that a client would use Bonjour/mDNS to locate an
Asterisk server. Then, it would try to register with no username and
password.  IAX.conf would allow me to restrict by context the client,
forcing it through some sort of voice prompts. The trick here is, if I can
find a way to extract the service identifier, I can combine the results
from the user supplied information to the voice prompts to generate a
service identifier entry in IAXprov.conf which, allows for something
interesting.

The next time the client tries to call, Asterisk will associate that
client with the provisioning entry and push down a provision data set to
the client. This will reset the IAX configuration data on the client to
new, user/device specific settings.

For a small setup where all clients will be on the same subnet of a LAN as
AstLinux, this somewhat solves the chicken-and-egg problem of provisioning
where DHCP is operated by another device rather than the AstLinux box. The
only trick being, the client must have mDNS query capability and default
behavior as I described.

Doing things this way, the client MAC address does not need to be known
ahead of time to generate specific config files to be downloaded. Also, a
specific end user could through voice prompts, select their own extension
during configuration. The big drawback is that the client needs mDNS
support, as well as supporting IAX optional components such as the service
identifier or provisioning data push. Also, there is a potential crowding
problem when multiple fresh clients try to go through the voice prompts at
the same time, since they all have the same username/password registration
(contested registration?)


Can the service identifier be easily retrieved from within Asterisk, or
would this require an ugly hack/patch? Would I be better off trying to do
some sort of packet sniff and try to grab the service identifier
externally, then pass that to an AGI script that the voice prompts would
be running through? Or am I better off scanning the subnet with nmap to
locate clients and do something (web GUI config and PHP direct access to
individual client webpages to auto-config the clients)?