Configuring polycom sip phones via tftp first and then ftp

I am familiar with configuring polycoms via the xml style config files.

I know polycoms can be configured to pull in firmware and config files either from a tftp server, ftp server or http server…in a large corporation, running a tftp server all of the time with sensitive info in it may not be smart nor wise…I was trying to figure out if there is a way for polycom phones (from factory) to update its firmware and pickup the username and password when first plugged into the network (from the tftp server, polycoms seem to be factory configured for tftp server) it boots up, acquires a username and password for a ftp server via the config files, and register itself with asterisk using a generic extension (basically to remotely reboot the polycom phone via sip notify packet, I am not sure if there is any other way to reboot a polycom phone without having it register with asterisk)

once the phone registers with asterisk using a generic extension, I can then create (via scripts) the final extension for this phone, issue a reboot via sip notify, on the next reboot, the phone finally reboots with its final extension number.

if someone knows of a way to remotely reboot a polycom phone without using sip notify (before a polycom phone registers with asterisk) as long as the phones ip address is known (from dhcp server) that would be quite handy…

thanks for any ideas, suggestions to achieve the above