I have an E1 connected to a 2800 series voice enabled router (from a PBX using FXS/FXO loop start signalling).
Now, I need to terminate calls on the 2800, and play an announcment (using TCL or VXML).
I also need to transfer calls out back to the PBX, after the announcment.
Are DSP resources required only when playing announcments ?
Or are they also required when doing a hair-pin transfer (no codec change involved in the transfer)?
And if required on a transfer, is 1 DSP's required per leg of the transfer ?